Japanese N/A L6 400hp, how they do it, pictures I've found, etc. Not 56k safe

[josh817]

Well I don't know if you've seen the discussion I posted before, with the 400hp N/A motors of Japan (http://forums.hybridz.org/index.php?/topic/87781-400hp-na-32l-how-is-this-happening). It went on for a while and died off however my efforts to find out their "secrets" didn't stop. I've really been wanting to type up a page or two talking about my findings. Kind of want to contribute some sort of helpful/useful material to Hybridz instead of being a boob every second of the day. I'm still searching Japanese blogs and sites for clues, but this is what I've found so far. I have way more pictures saved on my computer, I just upload a few to show what I'm talking about. Some basic things I've gathered were:

-N42 base head

-welded chambers to 36cc

-46/38 valves

-HUGE ports that don't do anything for you until you're high up the the RPM range

-intake ports must see at least 220 CFM for this sort of power

-exhaust must see at least 150 CFM

-flywheel flange on the crank will be milled by 6mm, or an entire new flange will be welded on (see picture, I find it bizarre), to prevent the crank from breaking

-heat treated blocks

-machined billet rods

-usually Kameari pistons which are forged

-12:1 compression ratio I made this bold because in the previous thread people were discussing that much higher compression ratios would help create power but when I found more information, these guys run a relatively conservative CR

-3 disk OS clutch from what I've seen

-typically 48mm Weber's or 50mm Solex's

-can't really say what headers but a lot of the 380hp guys I saw the numbers 45mm and 48mm coming up. Kameari sells both size primaries. A 48mm primary will yield best results as far as scavenging effect and exhaust tuning goes, at 8000 RPM, I think it was that I had read on ClassicZ

-all of the guys are running that big exhaust can type muffler. If you've ever seen the Kameari drag muffler, they look exactly like that. However from what I've read, the majority of them aren't running the Kameari drag muffler, but they are running a home made muffler. I'm going to take a wild guess and say that the concepts and designs between the home made and the Kameari drag mufflers are the same

-there is something about the exhaust that is special but I can't figure it all out. I don't know if its stepped headers or maybe something within the Kameari mufflers but Kameari advertises "huge torque and power increases" when using their header and muffler together on the same system. My point here is that the cams I see these dudes running, although I don't have specifics on them (wish I did), I did find some guys measurements from an Australian board. He had purchased a Skyline and was taking the motor apart for a rebuild, so everything he found out he would post. The cams these guys run are a lower lift than the big typical Schneider cams, they run about .530"-ish of valve lift[i just received an email from someone saying that the lift is "huge" so I think this .530" lift is too small. It is however the cam size that the Australian guy was running]. Their duration, at least the cam for this guy, was only 241º @ .050" for exhaust and 251º @ .050" for intake. This is the smaller cam that the dude had purchased, because his car came with a monster Japanese cam. I would think there would be a little more duration to bump that power band into 7-9000 RPM range, and they run LOTS of overlap. That's why I think the Kameari exhaust pieces are something special, because these guys are running tons of overlap, I think that tells us that they are relying on the scavenging effect.

 

Exhaust

"Exhaust pressure" was a popular phrase in all the sites I found, so I'm curious if there are some sort of nozzles being used. Oh and by the way I keep mentioning Kameari because a lot of the guys are running their products, or something similar. I did a little more research on exhaust but i couldn't find anything of great use. One clue to me was seeing a picture of the back of this guys car. The muffler was a big 3" in and out however it had a little 1" hole for the exit which was concave shaped, I'll post a picture. My initial thought was maybe they are putting some sort of nozzle in the muffler. If we look at convergent-divergent nozzles aka De Laval nozzles (http://en.wikipedia.org/wiki/De_Laval_nozzle), you can kind of get a fishy feeling that something is up. The shape looks suspiciously similar. While walking back to my car after school I passed a Honda S2000. It had a typical rice can muffler on it but when I looked closer, it too had the big 3" tip coming from the muffler, but within the tip was a tiny 1" hole. I'm thinking maybe a nozzle has some sort of weird affect. I don't fully understand it though because I always thought in order for a nozzle to really do anything you need a substantial build up of pressure behind the "throat", which would hurt performance. Likewise, if you have enough pressure to hit sonic or supersonic velocities, apparently the flow becomes maximized through the throat. Does this choke the exhaust, or does it increase flow? Its a weird process to me, hell I'm only a freshman in Aerospace Engineering so what do I know, yet. I do know however that the divergent part of the nozzle is divergent in order to decrease the gases velocity and in the case of rockets, it directs the flow of gasses so it doesn't just spray all over. The velocity of sound will increase or decrease according to temperature. I suspect that maybe the Kameari muffler does in fact have a nozzle in it because the exhaust side of the nozzle (divergent side) goes out to open air, which has a lower ambient temperature than the exhaust gas within the pipe, therefore making the the velocity it takes the gas to become sonic, lower. if you read the Wiki article, you will see the importance of achieving AT LEAST sonic velocity. The one thing that bugs me is that I don't know the velocity of typical exhaust gasses, are they even sonic? Maybe right when it comes out of the exhaust port, but if the nozzle is in the muffler at the back of the car, you must find a very efficient way to contain the heat, all the way to the rear. Higher compression ratio which needs higher octane fuel should bump the velocity up too, so perhaps higher compression engines will notice more of an increase.

Note the mufflers! Oh and by the way, the guy who owns the blue Z here, the one I said may have a nozzle, read our thread about the 400hp L6 and it appeared that he was laughing at us freaking out. I found a link to the thread in one of his recent blog posts. I was kind of embarrassed getting caught being such a noob, but I want to learn.

From RHDJapan.com:

View the blue Z's exhaust note here. It is the ONLY media I have of the nozzle looking thing:

If you notice in his videos, there is a small screw thing on the right side of the muffler tip. I suspect thats a set screw to hold the whole cone/nozzle assembly in place.

In this video you can see that when he rev's up, the exhaust smoke is shooting out at great speed, which makes me think "nozzle":

 

I also looked into cookie cutters in megaphone exhaust tips. I don't know if any of you guys have seen an old classic 911 race car. The idea came to mind last time I waved flags with our club Corinthian Vintage Auto Racing. There are at least 5 very fast 911's. They run headers, connected directly to megaphone tips. Some guys run dual megaphones, others have the exhaust that join together into one 3" pipe that dumps to open air. Anyway, the cookie cutters are these little things that sit on the tip of the megaphone. It took me forever to just find the term "cookie cutter". I didn't know what to search for or how to describe what I saw. Eventually when I found the term cookie cutter, I did a search for that. Still only had maybe 3 or 4 things pop up. Of those 2 of them told me what I needed to know "What the hell is this **** in your megaphone?" One answer was that they were put in there because the resonance of a Porsche exhaust (if you've ever heard an old 911 on the track, it hurts) is nasty and would crack the megaphones, so the cookie cutters strengthened them. The other reasoning for them was the Coanda Effect. Its hard for me to explain, so read about it here: http://en.wikipedia.org/wiki/Coanda_effect. If you're too lazy, the best attempt I can make is that the cookie cutters form a venturi within the megaphone because a moving fluid which moves across a surface will want to stick to the surface. Kind of like how an airplane wing has the air "stick" to it as it flows over and under. Once the "sticking" disappears due to too much angle of attack and what not, you have a stall. You can play around with different designs and see the effects of different angles and cambers here: http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.html. The cookie cutters were also supposedly used in hopes to reduce exhaust swirl, which I think is a flow rate killer. With these 2 ideas in mind, perhaps using cookie cutters within the megaphone, or maybe even as far into the system into the secondary collectors of a header, could help draw exhaust out. With massive valve overlap, this could potentially be quite useful! The key is not to impede flow I would think. Porsche bolt on 24" megaphone tips can be bought at like $140 a pair. The inlet size may be a bit small, its smaller than 2". you can buy blank 24" or 12" megaphones from Speedway motors for like $25 each, weld in your own cookie cutters.

 

Bottom End

The bottom end for all motors is essentially a pump, we all know that right? frequently said, the bottom end is in charge of reliability while the top end is in charge of power production. As Tony D explained in the 400hp thread, RPM's are key. A better way of explaining our Z Wiki's phrase is Formula 1. Over the decades they faced numerous displacement caps. The only way to make winning horsepower over your rivals is the achieve higher RPM's. Higher RPM's yields purpose to huge intake and exhaust ports for lots of velocity, which calls for higher duration/overlap/lift cams, higher compression will complement the bigger cam. Our problem here in the states, from what I've been reading, is that we prematurely go boom (don't you hate that). To achieve reliability (that's relative, remember that, you won't hit 200,000 miles and go "my Z has just broken in!"), from what I have gathered, you need a balanced setup. Everything! Pistons,rods, flywheel, clutch assembly, front balancer, everything. I can't do the calculations of how much **** is being flung around in your motor but just a several grams difference can ruin your day. Also, keep your flywheel and clutch assembly to a minimum! You may be sitting there going "but I don't need a triple disk clutch that's fancy and expensive, I feel the same way, but at 9000 RPM the torsional torque involved will also, ruin your day. Keep the assembly as light as possible if its a track car I would say. A lot of the light setups aren't very streetable anyway. You know, when you run like 9 pounds for clutch, pressure plate, and flywheel, kind of hard to pull away, but your saving your crank. It loves you now... Somewhere on here the shaving of the rear flywheel flange came up. The idea was to prevent the crank from snapping right behind the flywheel flange. The harmonics involved all seem to go to that one point or something. The science is unclear to me. This is one of those things I would just do, and say "yah I did blah blah blah" but have no idea whats really going on. Kind of like shot peening rods, I don't necessarily understand it to the fullest extent but hell, for $80 or whatever I paid, I did it anyway. I recently found a picture of a crank that had just a snout on the flywheel side, and a machined flange was fitted onto it and welded, I'll show a picture as I promised. Other big things to consider is cross drilling the crank for better oiling. Monzter, a member on here, probably knows all about oiling and such. The block, I have read in some instances of cement block filler being used. Don't ask me how or where, I don't know, but they do the same to the heads. One thing I did see was heat treated block. I think i even saw billet main caps being installed, over kill for me, but whatever you like. I don't see the caps being necessary, but have seen pictures of broken caps, I'll show that too I guess. More discussion about crank and block capabilities at high RPM can be found here: http://www.classiczcars.com/forums/showthread.php?t=17606 (mods if you don't like me posting links to other Z sites, can you just edit it out rather than ban me forever ). Also more reading on harmonics if you're so interested can be found here: http://www.bhjdynamics.com/downloads/pdf/tech/BHJDynamics_Damper_Info.pdf

Note the polished crank case and how it turns graphite color when heat treated:

Thanks to the user "Phred" for posting these pictures. He's probably on here too, somewhere:

Don't lighten the stock flywheel too much! Its a good way to chop your feet off if it shoots out your way:

Mods, correct me if this isn't in the right section...

I'm taking a break right now. Been at it for an hour or two. Discussing the cylinder head is going to take a little while, read this while I'm doing part 2 later tonight.

Edited March 23, 2010 by josh817

[260DET]

You are a ferret, thats a good thing, great research

[datsun723]

 

Waiting for the second part....great write up Josh.

[Daeron]

Wow, Josh, thanks a ton for all the info-mining!!!

 

Your discussion on the exhaust intrigues me, and I immediately noticed you said 38mm exhaust valves, yet 48mm exhaust primaries. Then you mention 3" in and out mufflers, so I presume esentially 2 inch primaries to 3 inch collector? Or would you say they run 3->2->1 setups, using an intermediate size piping? I can see either 6 into 1 with 2"->3" tubing, OR 3 into 2 into one going 2", then 2 1/2", then 3" main exhaust pipes. What I mean is, I can see two different flow patterns there and I am curious which way they typically go, from what you have seen.

 

Regarding these mufflers, are they essentially:

 

3" tubing going in, expanding to a tank 4-5" in diameter, then out to a 3 inch tube, which then has this venturi neckdown thing in it? Also, it seems like there are some iterations where this venturi dumps straight to atmosphere once it re-achieves full 3" diameter, where some of them have a recess, and there is a run of full 3" diameter pipe after the exit from the venturi. (At least, some pics are hard to see anything inside the tip of the pipe.)

 

Last week I was told by Sam Neve (a very reputable east coast L6 builder) that they saw a 20 horsepower loss/gain on a dyno by removing and adding a 6 inch long outlet pipe from a muffler on a particular car, and since then he never sets up an exhaust without a decent length straight run of pipe coming out of the muffler. Given that tidbit, this talk of muffler exit strategy is interesting...

 

 

 

BTW that second vid... instant classic!

[BluDestiny]

Need part 2. This is the most interesting reading ever.

[josh817]

Daeron,

I haven't found a lot of pictures of headers however the setup mentioned from the Australian dude was not a winning combination. He purposely went down to a smaller cam because he didn't want all the power way up top. Likewise, his header probably wasn't best suited for higher RPM's. He was the one that had these dimensions:

-6-3-2 the pipes didn't join together at all. They went to that classic Skyline muffler you might recognize, I'll show you

-42mm primaries

-52mm secondaries

-43mm pipes to the rear

He was also only running 40mm Webers. Basically he bought the car, went for an engine rebuild, found all this special stuff on it including some huge port job from the motherland. However his setup wasn't entirely perfect but he was ok with that. In the thread he goes on to discuss that he wanted to spend his money on other parts of the car.

 

His header was like this, there are a lot of Japanese guys posting pictures of this header too. This is from Datsun Spirit, the guy is the owner of the orange G nose Z that has the 6 slide carbs, you will be hearing about him later...:

The guy in the blue Z with the nozzle things ran something similar I believe, you can see them wrapped, on the floor. His dyno runs yielded 360PS or so, past 7000RPM.

However the top HP guys I'm seeing run the big sexy headers. Note, I'm pretty sure most of us can't run the Kameari "octopus" arm headers because they won't fit around the steering column. If you have a right hand drive car, you will be able to. This is 6-1, its a 3" collector.

Wako (you will be hearing about them when I talk about heads) made some headers like the Kameari octopus type. Here is a screen shot from their site, primaries are 850mm long, note the Engrish which the webpage translator gives me :

We can also see the tiny hole/nozzle thing being used in these pictures:

That set screw on the side must be used to remove the contraption because I once had a picture of the same dyno day, but the little cone wasn't in the muffler. Maybe they were testing it. Also, don't let the canister size fool you. Unfortunately no one wants to spend $2000 and cut the muffler in half, however I don't think it just opens from 3" pipe to like 6" inside there. Maybe it some sort of guts... I was doodling in class the other day and thought it would be cool to cut open a glasspack, take the guts out, and replace it with a nozzle. Put it at the rear of the car, so the divergent section is extended with a 24" megaphone tip. With this design, you have the extension as you mentioned, you have the nozzle, and when placed at the rear for the exhaust to exit, the ambient temperature of the outside air will help the flow become sonic or even super sonic. The doodle looked like this:

This is the Skyline muffler I was talking about. It has a specific name, can't think of it, but that one Australian dude ran 2 pipes into that:

Oh and by the way, Wako was also selling crankshafts. Kameari does too but they advertise as "modified", never say anything about whats different. Wako had mentioned "crank shortening at rear" which makes me realize that the flywheel shortening method is not just some Jo Shmo at home telling his machine shop to do something weird. The importance of crank shortening, must be high. One blog said shorten by 6mm, I can't find any other information on it. I think it would be cool to replicate however I'm curious if the shortening process opens up a can of worms such as, will the flywheel hit the block, does the rear seal do its job because I believe the ring rides along the surface of the flywheel flange? From what I see in my old pictures, that flywheel can't go back 6mm...

I have class in 10 minutes, I'll write about the head when I get home in about 2 hours.

 

EDIT:

Looked around more and found more detailed pictures of some headers. I found that they do in fact make the octopus arm headers for LHD Z's:

RHD Style:

Looking into the collector, no steps or anything:

 

I don't think there is anything unusually special about the headers other than they're a work of art. They're stainless steel, perfect welds, equal length, unique primary size, and the bends are good. Kameari is an specialty shop so of course prices will be high. This singles out the muffler, and you know, maybe the muffler is just regular old muffler. Maybe there isn't anything in it at all. The tip on the muffler is rather long, so that could be some technology, but the nozzle thing isn't blatantly at the very edge of the tip like we've been seeing on the cars. It might be some home made design. I'm not saying all this typing is useless, but I don't want to credit all 400 horsies to some pretty headers and a muffler.

Edited March 25, 2010 by josh817

[JIM73240Z]

Wow, some one has done some homework, maybe not their (school) homework. Nice finds. keep digging.

 

jimbo

[ModernS30]

Well, I was thinking about this. We run velocity stacks on our intakes to increase the incoming air velocity. The same concept should work on exhaust, if you make it get smaller like that then it should increase the velocity, doing this at the very end then making it run back to a larger exit more quickly should keep the velocity high until the gasses actually exit the exhaust. The way the header works is as the exhaust comes into the collector the way all the pipes run together cause the exhaust to cyclone, which should in turn also increase the velocity.

 

My dad designed some mufflers for his sprint car that were just 2 pieces of semi stacks or something with 3 inches in and outs that only had 2 plates inside them with slots cut and then they were bend to have the "Cyclone" effect on the exhaust. This was an attempt to increase exhaust flow. I will take a picture so you can see. They are kind of a crude design and were make a while back. I was surprised at how much quieter the made and open header v8 just welded to the headers. I can not say as to if they did any good or not. Exhaust is a big deal for low end torque as I am sure most of you know.

 

Keep up the posting, very interesting reading. I will definitely keep up with this!

 

EDIT:

 

Picture of the muffler. It's like maybe a 4 inch with 3 inch or something. I will measure later. They were run on a 355 powered dirt sprint car. Just one of my dad's ideas, seems to have lots of them!

 

EDIT #2:

 

Just adding another picture, the cone in this one posted above looks to have slots in it. Something to look at and think about.

Edited March 25, 2010 by ModernS30

[proxlamus©]

im very curious to see Monzter, Tony D, John C, Jon M, and JeffP's input on this thread =)

[ModernS30]

We are just way overlooking it all. Here is your answer. Just browse their site. They have it all. Even a forged 3.2L stroker (85mm) crank. Almost 5g's for a head setup! http://www.kameariusa.com/L6_SPLCylinderHeadUpgrade.php

[josh817]

We are just way overlooking it all. Here is your answer. Just browse their site. They have it all. Even a forged 3.2L stroker (85mm) crank. Almost 5g's for a head setup! http://www.kameariusa.com/L6_SPLCylinderHeadUpgrade.php

Yes, this is made to discuss what the hell is going on, how this is all functioning so successfully. Notice how its one picture, and its tiny. :P

Edited March 25, 2010 by josh817

[ModernS30]

Well, I just added up the most expensive parts they had to build an engine, still no water pump, but have a gear set for the trans and the rear end clutch, flywheel, pistons, rods, crank, oil pump, pully kit, head, cam gear, all of that good stuff. For basically not even a full race engine build, lacking only a few things. Your tally comes to about $24,000 before you get into intake manifolds, distributors or edis, exhausts, turbos or whatever you plan on doing. I might have left out the head gasket but I think that head comes with one. I bet you could get some serious power out of it but you would need a different clutch. The ones they sell are max of 400hp. I am super curious now though, how are they doing this. Do they really have this much $$ in their engines? Car stuff is cheap in japan I know this I lived there for a year, but not $10,000 cheaper! Oh, my quotes are without shipping and everything of course. Just from the prices listed on the site.

[josh817]

Alrighty here we go...

Cylinder Head

Ok if you haven't done all the basic reading on our forum (http://forums.hybridz.org/index.php?/topic/39134-big-and-nasty-headwork/) then do it now. Paul explains what he does to difference heads and his preference for different types. First thing is first, everyone except for one person who ran an E88, is running an N42 head. Basically to sum things up, they weld and reshape the chambers to 36cc and then they do a port job. One thing about the chambers, they're all running 46mm intake valves and 38mm exhaust valves. That's 2mm larger, on both valves, than the stock P90 head which a lot of us call "big valves" I believe... These valves look like they are right on top of each other! Crazy as it may be, combine this with huge ports and a select cam, and I think this is your power maker. 36cc chambers with 1-1.5mm head gasket and flat top pistons that are fly cut, will yield a 12:1 compression ratio for these guys. The port job on these heads are extreme. Most them are right on the edge of breaking through a water jacket. The Australian guy found that his head was a crazy ported one. When his machinist blew out all the gunk from the ports, he accidentally broke through a spot in the wall where it had been patched. Patching material can be various things, the one I found was Devcon. Its industrial strength, they patch nuclear reactors with it... for godsake they fix bolts with this material, its tough enough. If you're poor like me, actually I'm just a cheap bastard, you can use Devcon filler to patch your screw ups rather than welding it, just don't use it a ton... Devcon is like Bondo, its two parts, and its like $100 per pound (or maybe it was 5 pounds) I believe. I don't know how many dudes are raising the ports to make it straighter, nor do I know what that sort of work looks like as far as welding marks go and such. I doubt they're raised much. One thing they will do is get rid of the valve guide supporting metal all together. If you don't know what I mean I'll show a picture, basically the guide is in the port all by itself unsupported. In Paul's typing he mentions "offset guides for even bigger valves", to be honest I never even thought about that. At first I was confused on what he meant by offset but then I saw a picture of guides from some other engine and I was like hey that's a good idea. However! The Kameari guides are not offset. The intake is made out of aluminum bronze and the exhaust is made out of phosphorus bronze which helps with heat and wear. They are also slightly shorter (stock is 59mm long, these are 52mm for exhaust and 50mm for intake), and they have more of an angle cut into them on the port side to help airflow within the port. One more thing is that they have "hats" on the top of them. I'll post pictures of guides, ports, and chambers when I'm done. You get more from pictures than me talking.

 

Now comes cam selection. This is a mystery to me, and it is one section that PISSES ME OFF. Why Josh? Because I went to a certain distributor of a Wako 75S cam, I inquired about it. Of course he asks the application and says, I quote, "Who told you about Wako 75S? I am Wako authorized distributor in the US so I can get it, but I don't sell it to everyone". What the hell?! You're going to deny me a sale because my "road racing" application (granted I just pulled that out of my ass) "can't run the Wako 75S" cam? Not only do I frown upon the idea that it "can't run" because it WILL run unless you have clearance issues (may not run like I want it to), but I also frown upon him for refusing a sale. I then inquired about the Kameari 77i cam (another high performance cam) and whether or not it is similar to the Wako 75s. The only thing he said was "75S is a few steps above 77i in terms not only of the performance but also of the engine spec to be able to run it." Talk about vague, right? To me its like, no wonder here in the states we are having difficulties. Only certain people have the "privilege" to own cams now, or know certain information. This is the original reason why I went out on my own and started lurking for "secrets". You ask this distributor what you can do to run the Wako 75S cam and what things are you forgetting in your build, he'll tell you one sentence and that's all. Not like any build secrets are being given away, if all I want to know is how can I use your product. The Japanese spirit must stay in Japan, it seems like, especially when he asked "who told you about that cam?" kind of surprised.

 

Anyway, after that little rant, if you haven't seen already, the Japanese aren't running brands like Schneider... Brands I have seen are Watanabe 75R, Wako 75S, Kameari 77i (they also have a 73A and a 75A series), and Electramotive L4-02. The guy that I mentioned above, said the Wako 75S is one of the fastest, if not THE fastest cam for L6's. With this cam and doing everything else right in the motor, you can do 11.2 second quarter miles. Don't freak out now, the guys also run a close ratio tranny and a 4.6 R200 so they can accelerate quickly even with a regular setup. These cam designers do not tell you everything, like Schneider does. They won't tell you duration or lobe separation. They simply tell you cam lift, valve lift, and lobe center. Valve lift is obviously cam lift times the rocker arm ratio (1.48), and I'm trying to figure out the importance of lobe center. For example the Kameari Super Drag 77i cam has a lobe center of 101º. This is where I need your help you guys! Tell us what the importance of lobe center is! I know what the lobe center is, I just don't know why they are telling me this.

 

The flip side of this story is that while these companies are protecting their work by not telling you all the specifics, I just happened to have found some information on the Kameari 77i cam. Took me an hour or so to decrypt all the Engrish that the translator spit out but I managed to get everything, they tell you the cam specs, what the valve to piston clearance should be, and what the lash needs to be set. I took my Schneider cam card that I have on the computer, erased all the figures, and then printed it out. I filled in everything with the Kameari figures and now I have a cam card ready to use. Kameari wants $1100 for their cam, and the Wako distributor wanted $1300 for his. Of course, it may be immoral of me, which is why I won't sit here and type all the figures out for everyone to see. I don't want some super cool company to be pissed at me or something. One thing that all these cams also advertise is central angle. If anyone knows the importance of a central angle for cam lobes, please pitch in! I suspect central angle and lobe centers are being given because these cams are asymmetrical. They ramp up fast and let the valve back down slowly so it doesn't get torn up. Since they are asymmetrical, I'm thinking the lobe center and central angle information is given to tell you when exactly that ramp up is occurring. The fast ramp up (steep side of the lobe) helps with "sudden acceleration". I think this was mentioned somewhere on here before because Dave Rebello uses the same technology on many of his cam grinds. If you go here: http://www.camaro5.com/forums/showthread.php?t=34774 he describes the characteristics of camshafts. He points out that with most cams, higher lift means duration is longer because it takes more rotation to ramp up to the higher lift. Contrary to that, these cams are running less duration. You saw in my first post, the cam had like 255º of duration. This makes sense to me because the rapid ramp up means less rotation to reach maximum lift, making duration shorter. However! If you look at one of these cams, the lobe is very wide! As in like it is at max lift for a while! This is what is confusing me because my Schneider Stage IV cam is .495" lift and 290º duration, it doesn't have a big long flat spot, yet it still has more duration than these "big cams". Not to mention, the lift on these cams are maxing out at 14.8mm which is .583". Schneider sells cams which not only have more lift but more duration. One more unknown factor is the 70-number. Kameari has a 73A, 75A, 77i, then Wako is 75S. I don't THINK this is overlap! The information I found for the Kameari 77i was position of intake open/close and exhaust open/close @ 1mm of lift, just like we have @ .050" lift. This measurement should justify the short duration I'm seeing, because I calculated the duration with these open/close figures. When Schneider advertises their cams, they don't tell us the @ .050" figures, they tell us the raw figures. Raw duration is when the valve first starts to open, that instant, to when it closes all the way. The @ .050" reading is the duration from then the valve first open and it hits .050" and then .050" right before it closes. My point here is that all our exhaust talk could be worthless because according to these @ 1mm figures, the overlap is only in the 60º's range. My generic cam is 78º overlap, but that's the raw figure I mentioned, its not @ .050" or @ 1mm... Even if the 77i in "Kameari Super Draw 77i camshaft" denoted overlap, its still the 1º off from what I have now.

 

This is the unfortunate problem. As you can see, I have so many unknowns. No one wants to share any information online, so I guess this stuff gets sent around by word of mouth and exclusive catalogs, and that's how you becoming "privileged" to use such camshafts. I found only one website which had the Wako 75S cam. Its central angles were different than the Kameari 77i by .5º (seriously), lift was the same, duration is most likely the same, but the distributor told me its a step up. I guess that's what makes me so undeserving, but what the hell right? If you don't want to help me with general information such as, and I quote what I sent to him, "I understand the dimensions of the cam is pretty much like a company secret however, what about cam characteristics? Is the Wako 75S like the Kameari 77i? Would you say the Wako is more aggressive than the Kameari cam? What makes you say the cam will not work for my application, just out of curiosity on where my weak points are?", then fine, I won't buy your product, I'll find out the information I need on my own.

 

Springs to be used can be a wide variety. I've seen Isky springs, a lot run the Kameari 9000 RPM and 10000 RPM springs, some did Tomei springs or however you spell it. You want good springs! They have to put up with high lift but also high RPM. If you aren't doing higher RPM's then why do you have this setup... Actually though, reviews for the megacams all said acceleration and response at 1500 RPM was still good! Another important thing is to make sure your valve train is light! Phred, from the previous link I posted, explained that one of his customers cars wouldn't rev past 9000 RPM because it was too much mass in the system. Heavier parts will lead to valve float at a lower RPM.

 

The main point to all this is that these Japanese cams have been proven, when paired up with everything else that they have done. All these questions that I have don't have to be answered necessarily because of the fact that these specs have been proven. All that needs to be done is replicate it in one of our own builds...

 

Ok so I've taunted you long enough.

Here is a head in rough form with welded chambers:

Comes out looking like this. This head has the 46/38 valves to show you the difference:

Monzter was running the Kameari 46/38 seats but a slightly smaller valve with the idea that it would unshroud them better:

This was from an L4 head, but the same concept applies for Z head, you get rid of the valve guide support. Still use Kameari parts:

Here is the difference with the valve guides, note the "hats" at the top. All thanks to datsunspirt.com of course:

Datsunspirit.com had posted this to show what a "standard" port job would look like an an N42. This supposedly yields 100hp/liter. The "special" port job that the big boys run is bigger than this. I believe this is the exhaust side:

Here is what a big boy cam lobe looks like:

This guy did an at home port job, built the motor himself, dyno'd to be 295whp. He conveniently marked the port sizes, in case if you don't know, that's millimeters :

And finally here are some miscellaneous pictures to show you the grand scheme I suppose:

 

EDIT:

Just saw Zredbaron posted his dyno video up and in the description it said "racing cam .565" lift @ 326/315 dur". I'm wondering if the Kameari 77i cam really is only 250 through 270-something degrees @ 1mm of lift... Performance at 8000 RPM comes from only that much duration...? Is it because their ramp up is so dramatic? Curious curious.

Edited March 25, 2010 by josh817

[josh817]

Well, I just added up the most expensive parts they had to build an engine, still no water pump, but have a gear set for the trans and the rear end clutch, flywheel, pistons, rods, crank, oil pump, pully kit, head, cam gear, all of that good stuff. For basically not even a full race engine build, lacking only a few things. Your tally comes to about $24,000 before you get into intake manifolds, distributors or edis, exhausts, turbos or whatever you plan on doing. I might have left out the head gasket but I think that head comes with one. I bet you could get some serious power out of it but you would need a different clutch. The ones they sell are max of 400hp. I am super curious now though, how are they doing this. Do they really have this much $$ in their engines? Car stuff is cheap in japan I know this I lived there for a year, but not $10,000 cheaper! Oh, my quotes are without shipping and everything of course. Just from the prices listed on the site.

I was definitely thinking the same thing when the guy told me $1300 for a cam! Unless they are really passionate about it, which I'm sure they are, I would think prices are cheaper over there. After what I've witnessed, trying to buy specialty parts and I'm the "foreigner" to the cool stuff, I wouldn't be surprised if prices were ramped up for the American market. I wouldn't blame the store owner though. Distributor prices are set by the companies. Kameari tells their distributors what to charge. Also like you said have to consider shipping, which hurts a lot.

 

I even wonder about the carbs because there seems to be a plethora of Solex 50mm, Weber 50mm, Weber 48mm, etc. If you have 45mm carbs, it seems you're the equivalent of 40mm guys like me here in the states.

Edited March 25, 2010 by josh817

[roger280zx]

Wheres TonyD at?

[MONZTER]

Nice reading and well done.

 

My quick comment is summed up by the quantity of material you have found. Simply, there is no 1 magic bullet that gives them the power. It is the well planned out, focused details in all of the parts. The sum of the whole is made from the parts. Everything is designed to work together, and when it is done correctly, the hp numbers don't lie. I'm sure I have some stuff to add, but its late.

 

Jeff

[ModernS30]

This thread has kept me up till 1:30 and I have school tomorrow then work after words. I think you should get your cam made and let us know how everything goes. It sounds like anybody with the knowledge could manage to get one of these cam's made for themselves. The way they do the welding and stuff is amazing. Still makes me wonder if I could manage weld a FranKAnstein head.

[josh817]

Nice reading and well done.

 

My quick comment is summed up by the quantity of material you have found. Simply, there is no 1 magic bullet that gives them the power. It is the well planned out, focused details in all of the parts. The sum of the whole is made from the parts. Everything is designed to work together, and when it is done correctly, the hp numbers don't lie. I'm sure I have some stuff to add, but its late.

 

Jeff

Well, we've pieced together exhaust ideas, bottom end reliability ideas, and head concepts as far as welding/chamber size/valve size/porting/camshafts. All this stuff put together should be a general solution to the lack of ponies. I'm sure there are still some little build secrets that you will have to find on your own to be successful, you know what that means... The only thing that's left is intake I suppose and I didn't bother on any of that. A lot of dudes posted their jet sizes and stuff but carbs depend on elevation and atmospheric changes meh. We know all these guys are running carbs or ITB's and no one went below 45mm.

Edited March 25, 2010 by josh817

[josh817]

This thread has kept me up till 1:30 and I have school tomorrow then work after words. I think you should get your cam made and let us know how everything goes. It sounds like anybody with the knowledge could manage to get one of these cam's made for themselves. The way they do the welding and stuff is amazing. Still makes me wonder if I could manage weld a FranKAnstein head.

I would feel like a rat if I had a cam reground to these specs. These guys worked hard to find the perfect solution and the work is exclusive, which explains the price. Me taking a short cut, ehhhhh, maybe. I'm still thinking things through. That's why I edited out the "I'll just make a regrind somewhere cheaper", out of respect for the dudes.

 

For ModernS30: Yes I think your dad was onto something. The Wako header screen shot I had posted read "cyclone effective preeminent". In this case, instead of having straight cookie cutters, I'd leave the center circle in place but turn the "fins" at a slight angle to put a swirl in the flow!

Edited March 25, 2010 by josh817

[Konish]

Well, I just added up the most expensive parts they had to build an engine, still no water pump, but have a gear set for the trans and the rear end clutch, flywheel, pistons, rods, crank, oil pump, pully kit, head, cam gear, all of that good stuff. For basically not even a full race engine build, lacking only a few things. Your tally comes to about $24,000 before you get into intake manifolds, distributors or edis, exhausts, turbos or whatever you plan on doing. I might have left out the head gasket but I think that head comes with one. I bet you could get some serious power out of it but you would need a different clutch. The ones they sell are max of 400hp. I am super curious now though, how are they doing this. Do they really have this much $$ in their engines? Car stuff is cheap in japan I know this I lived there for a year, but not $10,000 cheaper! Oh, my quotes are without shipping and everything of course. Just from the prices listed on the site.

 

Car stuff cheap in Japan? I've lived here for the last 5 years (not concurrent...2 years the first time and 3 years currently and 3 more to go), and the stuff is *far* from cheap. Used parts? Maybe...depends on what you want, but aftermarket stuff is crazy expensive. If you still have contacts here, have them pick up an issue of G-Works magazine for you...it'll curl your toes.

 

R/

D