This is great! Now all I can see are my posts - which are the only ones worth reading anyway.
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Posted by 2126 on 23 August 2006 - 01:48 PM
Posted by Derek on 19 September 2014 - 09:47 AM
This is all Tony D’s fault:)
Hi everyone. Some of you know me from my DIY EFI manifold project
Well now I’m tackling a DOHC head.
I get a PM from Tony D in September of 2012 about the Goerz-Paeco DOHC L6 Head coming up for air.http://forums.hybrid...?&gopid=1020596
Which led to a brief discussion about what would be involved in producing a head. And that was the end of it... Or so you thought.
Tony and I started trading emails about the feasibility of producing it and what kind of heads we could use as a donor for the valve train. Tony suggested bringing Jeff P on board because of his work with cooling the L6 head. Tony and I kicked around RB and KA motors for a while and then Tony suggested checking out the Honda K20. Bingo. Removable cam towers, factory roller rockers and a plethora of aftermarket parts. I called one oh my clients that is big in the import drag market and procured an old K20 head. I did some quick measurements and decided that it was probably workable. And so the journey began.
The idea is to use the cam towers and valve train from a K20.
I grabbed a quick scan with my white light scanner of the exterior. It’s dirty because I’m only using it as a reference scan to design against.
I imported the scan into my solids program and then proceed to replace the mesh with solids.
Jeff provided me with a great CAD drawing of his head gasket to work from. I decided to take a module approach to model the head. I made a single cylinder complete and the copied and offset it for the other cylinders.
I then pulled the solids together to create a single model.
At this point I was at a standstill until I could figure out what to do about the timing chain.
Jeff and I had a long conversation about pros an cons of various designs. The preference would be a single chain so I ordered up a K20 set to see if it was workable. NOPE.
Lower timing gear is too small to bore out to fit the L6 crank. Back to the drawing board.
I decided to give the KA set a try. I decided the Altima set would be a good choice as it’s only a single row chain up top. With the roller rockers I don’t think you need a double row.
I did a rough mockup on a piece of wood mounting all the pieces.
Then I machined a chunk of plastic so I could actually mount it to the block.
You can see I’m trying to incorporate the KA guides and lower tensioner but that won’t happen without a new lower timing cover.
Here is the lower section with stock modified L6 components. The only tricky bit is I need to remove one link from the chain. I think this is a workable solution.
Now I could finish modeling the front and back of the head.
Next the front timing cover. The water outlet exits the head in the front and makes a 90 degree turn through the timing cover where the thermostat housing will mount.
Now the valve cover. The K20 cam towers kind of dictated the overall size but I was still able to get the styling I was looking for. I was trying to have the flavor of the S20. I’m still tweaking the design but so far I’m pretty happy. The “NISSAN” and “3000” will be machined in so they are kind of placeholders for now.
After talking with Jeff about his testing on coolant flow I decided to get the most out of the 3D sand printing process as I could. I designed a water jacket that would be pretty hard to duplicate traditionally. There is a lot of surface area so hopefully there will be large improvements in cooling.
Here is a nice shot of the intake and exhaust cores, water core, and upper tensioner. You can see where the cross drilling will go to supply oil to the head, tensioner and idler gear lube.
There will have to be additional oil supplied to the last three cam towers as the single feed in the front won’t cut it.
Here is a cross section of the head. The cut plane is through the center of one of the intake valves so the ports look a bit off. There is machine allowance on the bottom so the combustion chamber is a little larger than it will be after surfacing.
Well like I said in the original Goerz-Paeco post I think this is a very viable approach to producing DOHC head. Should make for an interesting conversation.
Oh and one more thing.
What good would a thread about casting a head be without.......
An actual casting.
We poured this Monday and I just got these pics from the foundry today. I haven't seen the head personally but we're pretty sure it is good enough to move forward with.
Still lots to do but you can't imagine how happy I am to get the first one right.
As long as things proceed as planned I will be selling these. There is still a lot to figure out. I have the foundry working up some pricing for me and I'll post that as soon as I can.
Thanks for looking
EDIT: I now have a blog about this head on my site. I'm going to continue to post here but the blog is a condensed version of what you see here. There is a FAQ on the left side bar that has a lot of data. If you are new to this build you may want to come up to speed there and then start following it here as there is a lot of great back and forth that isn't on the blog.
Posted by ThomaZ on 27 July 2006 - 11:38 AM
As recommended by members on this board I used an 7/8" master cylinder (MC) from Wilwood (WIL-260-6765 at Summit). It fits the hole pattern in the firewall without trimming. I installed an AN4 fitting (like Summit RUS-66042-1) and a custom-made steel braided hose down to the stock GM plastic slave cylinder (SC).
The set up had several disadvantages. The connection to the plastic SC was fragile. I hade to hammer a bulge into the lower part of the fire wall to get sufficing clearance for the cutch arm.
It was so difficult to bleed. I didn't get it to work well. The clutch disengaged, but just barely.
The SC ended up very close to the down tub from the headers. I made an heat shield but it doubt it worked.
After just 1000 kilometers (625 miles) the SC quite and dumped all the fluid out around the pushrods. I was reluctant to just reinstall a new plastic SC so I started to investigate an alternative; and bellow is what I ended up with.
I used a SC with aluminum housing from Wilwood (WIL-260-1333 at Summit Racing). It is a pulling clutch SC so it needs a new mount and a modified clutch arm.
The stock clutch arm was shorted and an a hole drilled in it for the push rod
I fabricated a SC mount from 1/8" steel. I made some simple cardboard templates an the cut it out with a hack saw and bent it in a wise. It was then stick welded together. I made it to pick up on of the "ears" on the gearbox housing and two mounting bolts on the aft face of the gear box. It is a simple design and I hope the photos will aid if you wish to duplicate it.
The stock nipple on the Wilwood SC was replace with an other AN4 nipple and I had a new steel braided hose made. It is 800 mm (31.5") long and has 90 degree bend on both ends.
The rest of the photos shows the system installed. It works really well. It was simple to bleed and it disengages and engages distinctively. As can be seen from the photo it clears the firewall and the trans tunnel. It sits higher up in the trans tunnel an clears the exhaust tube with comfortable margin.
The disadvantages is that you must remove the bell housing from the engine to be able to remove and install the clutch arm and the clutch arm is hard as nails to drill in! Use a drill press, top quality drill bits, work slowly and use cutting fluid.
I have now put approx. 2000 km (1.250 miles) on it and it still works well, so I thought it would be something worthwhile sharing.
Posted by T-Bone028 on 05 October 2014 - 05:41 AM
If you search my posts, you should find an off the shelf parts list and how I set it up. Part came quickly and shipped the day after I sent paypal. Definitely recommend!
Posted by NewZed on 12 March 2013 - 01:51 PM
Recent posters are ignoring or unaware of the history of Ben's Z's project. If you don't consider his other threads it does seem like Tony D just walked in to the party and started acting like an ass. But Ben's Z's project is a series of errors and ignored advice. He seems more focused on venting on the forum than actually doing things right. It's almost like he goes out in to the garage to screw something up so that he can come here and bitch about the injustice of the world.
You do have to give him credit though, for continuously coming back to expose his lack of skills, and for more of the resulting verbal abuse. It's certainly entertaining and I'm looking forward to future threads about the blown engine/turbo/transmission or whatever, once he gets it running, in the the next year or two.
Posted by josh817 on 23 March 2010 - 01:51 PM
-N42 base head
-welded chambers to 36cc
-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 241Âº @ .050" for exhaust and 251Âº @ .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 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....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.
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..../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....ane/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.
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.classiczc...ead.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.bhjdynami...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.
Posted by frank280zx on 26 February 2010 - 07:22 AM
And yet, the rear end in the ZX was still a mixed-bag 810 transplant that ANY hint/hope of making it less pedestrian than it's sedan roots would have been welcome. What important is the turbo 280ZX's legacy. That legacy is being a stellar parts car for 1st gen cars that don't need to deal with the cheaper and schizophrenic semi-trailing arms at all.
Want me to take you up for a roadrace challenge .. and see the cheaper and schizophrenic semi-trailing arms blow your doors of ? I think the 280zx did ok racing .. and lets not forget the BMW m3 ... also one with the cheaper and schizophrenic semi-trailing arms.
(At least if a bear attackts it i can fix it with duct tape)
Posted by nicamarvin on 02 November 2009 - 01:46 PM
Well I feel the crank would have to be re-drilled since the stock oiling hole would pretty much fall directly between the two rods and most 4 cylinder engines have a rod width roundabouts 1inch while the stock chev rods are .940 width as well. If you managed to wedge two custom rods on there the width would probably be well below .700 width which is starting to get skinny.
well, we all know there needs to be custom thing to do, but to me this is the closest thing to a Flat plane I could ever get, plus I don't intend to reve this thing past 6K I just want that cool sound too
Posted by milesz on 06 March 2008 - 03:24 PM
Posted by Barrel_Ball on 12 July 2016 - 04:56 PM
Figured I would post this here, as it pertains exclusively to the first generation Z car. I've seen power window kits that involve a remotely mounted motor, a cable/chain drive of sorts, to a little splined tube that slips over the stock window crank spindle.
Problem is, while it may be good enough for many, I find that the fact that there's a protruding black, plastic cap on the door panel where the crank once was, is kind of cheap-looking in my opinion.
So I decided, while my doors were apart for bodywork and other repairs/upgrades, to try a power window conversion of my own. Keep in mind, though, that the doors are currently (as of typing this) not on the car, and the switches are not wired into the car, yet (we're re-wiring the car at this time, in fact). So let's go through this with the pictures I remembered to take during the conversion:
The motors from the front doors of an '05 Subaru Impreza. The gear tooth pitch is the same as the original spindles, with the two minor details to keep in mind being: The Datsun spindle has 7 teeth, while the Subaru motor has 8 teeth, and the pilot hole needs to be drilled out a little. I don't remember what drill size, exactly. Just make sure it's snug, but still moves smoothly
I started by drilling out the three riveted points holding the original spindle in place, removing it. I then determined where the motor had to sit, marked off the area it needed to go, and cut into the bracket mounting flange, so that i could flatten it out around the spindle area.
You can see the two holes I had to drill out for the motor to mount. Note the screws.
I layed out where everything needed to go on the door to check for any interference points. All clear, so far.
Demonstration video of preliminary test here.
I bolted the un-finished assembly in place to trace where I would have to cut metal out of the door, as the motor will have to sit through about 1/8" - 1/4".
One session with the zip-wheel later...
Just pokes through...
Assembled everything on the door for clearance/bind testing. All good.
Assembled operation test video here. Still needed to final-adjust rails, hence why it wasn't put up all the way.
The finished brackets with motors mounted.. I had to trim some of the motor flange back on the regulator, and weld in some trimmed 1/2" x 1/2" angle steel channel on either side to brace the regulator, as well as provide a new mounting flange for the door, complete with new captive nuts.
Hard to see here, but I welded in a section of sheet metal to fill in part of the void where the original regulator came through, to add structure back into the doors.
Doors are now assembled, adjusted, and sitting in a shed until they're needed for the car's final assembly
Not pictured are a pair of rear door window switches from a mid-90's Honda Accord. They are 5-wire, which can handle the current these motors will push. Plans are to use a 20A stud-type circuit breaker per door, may use 2 if deemed necessary. The switches will be mounted in the change pocket of the center console.
Not my best install writeup, but I hope this helps anyone who would want to do this type of conversion in the future.
Posted by bradyzq on 23 March 2015 - 05:34 AM
I thought it was time to shout out a big "Thank you!" to the hybridz community for keeping the Z flame burning in me for the past (not so) few years since I last drove my Z.
It seems that other priorities in life have jumped the Z and moved to the front of the line. This isn't permanent, but in the meantime, it sure helps to read all these threads and occasionally be able to help out and/or learn something along the way.