Whittie

Hi mate, welcome to the forum!! As for forum section, maybe 4-cylinder? I don't think it really maters, not that far out. As for the motor, that sounds INSANE!!! This is an sr20 yeah? believe thats what the gti-r's ran, or atleast a common upgrade, not too up to clue with the things, even tho i love the idea of them!! As an HKS demo car i fully believe 500hp!! There is no doubt it will be a monster. I assume you want to put this into a zed??? (you're thread title and post is kinda vague...) Might need to put a few more details up about the engine and the car getting the upgrades. Plenty of powerful sr20 engined cars on this forum so you won't have any trouble getting help As for the gearbox, the s13 and s14 are identical, however there are plenty of stories of people with less power doing real damage to them. I am led to believe these things are good for about 400hp. Depending on how hard you drive then they can take more, but if you're doing an ex-HKS engine swap then i wouldn't bugger around with the gearbox and i'd go straight for an RB25DET TURBO box. Reputed to hold near enough 1000hp, it wont break. They take some serious work to fit (They are MASSIVE) into a Zed, but as far as onto and SR20 is concerned it simply requires an adapter plate. I don't know where to get them but i know they are readily available and go for around $300. Get some updates up and let us know how it goes!!

I have both 4.375 and 3.9 R200 VLSD as well as a 3.5 VLSD. We used shims on them (the 3.9 and 3.5 from memory) just used a metal pipe that was 10mm inside 12mm outside. Basically what you did. Have been racing the car for quite a while now with no dramas.

Haha, yeah it sure is That pic is going to my mechanic on wednesday when he fabs up the same thing for me You said it was your first welding piece ever, but i have no welder so they are doing it for me. Seriously, that looks fine to me. Make it a bit tidier on the welds and joins perhaps and it would be what i am hopeing to have on my car. I don't know why the guys were bagging on you. I have that thread bookmarked in my "Z gearbox Swap" folder

I am in the process of doing this swap.... Infact i just picked up my modified bellhousings today from the shop... The bearing and shaft holes are the ones that need fiddling with. The SR bellhousing has a larger bearing hole than the l28. HOWEVER, the inside diameter of the two different bearings are the same. Therefore, just use the SR bearing, the L28 shaft will fit on/in properly. The only other thing to contend with then is the fork hole. It is 16mm instead of 14mm, so you will need a 16mm outer diameter, 14mm inside diameter spacer to wedge in there. The other 2 holes, not circled in the picture above, do not need altering. THAT IS IT!!! One more thing.... WHY?! Seriously, the drive shaft will cost you MAX $150 to have it shortened and balanced with new cv's and the dust cover taken off and the SR gearbox is TONS stronger than the L28. My N/A L28 is punching 180rwhp, 240rwnm and i've been through 4 gearboxes in 18 months. The Z gearboxes are just getting old. The NEWEST Z gearboxes are 30years old.... Their at the end of their servicable life in my opinion. The SR gearbox is an UPGRADE, and the SR gearboxes are about half the price of an L28 gearbox.... (well in AUS anyway)... So whilst, YES, you can do it, and it wont be difficult (see above), i just dont understand why you would want to do it when it will be far easier in the long run to just make a new driveshaft and tranny mount. If you have a 240 with the tranny mount that bolts upwards, then all you do is turn the original mount around, and drill two new holes ~5mm further back on the mount, and your tranny will bolt straight in (the Z tranny mounts fit on the SR20 gearboxes). If you have a 260, where the tranny mounts are parralel with the gearbox tunnel, simply cut the centre section of the tanny mount out and re-weld it 35mm further back. Viola, tranny mount lines up. Another thing. Why not put the SR20 as far back in the engine bay as possible for weight distribution? Friend is doing this, the tranny mounts (SR20 box) are basically the same procedure as i just described, and the tail shaft just has to be shortened the correct amount. PICS. (see attachments) side by side comparison gearbox bellhousings 260Z gearbox mount modification 240Z gearbox mount modification Useful link: How to install an SR20 gearbox into a 240Z http://home.comcast.net/~zheimsothtn/transmission.htm

Arif, I have a standard 260Z box with upgraded new-model synchro's, and when the gears are worn, i have this exact problem. Happened on about 3 gearboxes now. Current issue is falling out of 5th under power. previous was 2nd when coasting at +4000 rpm, first was 1st gear under power. It could be a similar issue for you, or the keepers as woldson says. Either way my guess is something is worn and has worn gear edges that dont 'grab' anymore and is letting the 'box fall out of gear.

The timing chain tensioner can fall out REALLY easy when you're putting the chain back on. Maybe it didn't seat back right and you didn't notice before putting the car back together?? I actually fashoioned a wedge shaped block of wood and jammed it in between the two sides of the chain to hold the tensioner in whilst working on the cam last time. Worked a treat. Put a little string on it so i could pull it out when i was finished without taking the front cover off too, saved a lot of hassle. I would think something like that would squeek all the time though, so I'm not too sure. The tensoiner is a block mounted to a rod that sits in the front of the engine and has a spring pushing it out. Kinda like how a pen spring works, where the spring forces the top of the pen back out. The tensioner can come out of its hole and the spring flicks off, or even just jams the tensioner. I had this problem about 3 times the first time i tried to put my motor back together. I know you said its coming from the timing cover but is it maybe the fan belt? Just throwing up options here... I'd check it out. If the tensioner fell off, or the distributor gear snapped (i've done this one ) it can make a real mess of your engine as it ruins the timing and you get MASSIVE pinging. Like the spark plug sparking still well into the upstroke.

Quoting WizardBlack: "If you visualize the flow of air through your entire intake tract, you might get a bit of an understanding why MAF cars are usually sensitive to externally vented BOV's and why installing the BOV closest to the intake manifold yields the marginally best performance. A MAF meters the actual flow of air, therefore the BOV must be rerouted back into the intake (before the turbo, obviously) AFTER the MAF. If you install it before the MAF, the MAF will register the air flow that is continually circulating. This will make the car run rich when you shift, roll off the throttle, etc. When you roll off the throttle (or shift), the compressed air suddendly finds itself slamming against the closed throttle. Just like a traffic jam, the air piles up against this blockage and then a pressure wave bounces off the throttle and works it's way backwards (upstream) to the turbo. It hits the compressor wheel and reduces it's speed; sometimes even making it spin backwards momentarily. This is pretty hard on the compressor and shaft. Someone smarter than I can compare it to the effects of surge and what typically fails first. Regardless of this, it disturbs the rotational intertia of the turbo and delays respool for the next time you press the throttle. A BOV releases the pressure and allows the turbo to continue to spin and harmlessly vents the pressure until you want it again. Now if you're still with me, you can imagine that installing the BOV as close as you can to the blockage (throttle) allows the entire intake route to continue to flow air forwards. If you install the BOV, say, right at the turbo, the air will bounce off of the throttle and have to travel all the way back to the turbo to find release (so to speak). Installing the BOV at the very end of the intake allows as much of the intake tract to continue to flow forward during vent. The ideal setup would be to install the BOV as far downstrem as possible and vent it right into the inlet of the compressor so it is used to spin the compressor and maintain as much momentum as possible. Hope that helps. On the subject of where to tap for the BOV: The BOV has a piston which is operated by vacuum/pressure and a spring. Whatever line is used to feed the pressure signal to it will get some movement from the operation of the piston. This can cause small fluctuations or delays in the pressure signal. Theoretically it isn't good to tie this line in with the FPR or boost gauge. Likewise, the BOV could fail or leak and alter your fuel pressure. A BOV can even hang open in vacuum (not a problem for MAP cars) but can flutter open and closed, etc (definitely a problem for fuel pressure). Many people install a BOV and crank it down tight so it sounds 'cool'. Most people will agree that the FPR's vacuum line is a lifeline for your turbocharged engine and the boost gauge line is your only chance of knowing when something is going badly and stopping it in time. Anything else on those two signals is an unneccesary risk to them. I personally tie them together so I know if the FPR line is ripped by seeing the boost loss and therefore getting out of the throttle. I also have a wideband, but every bit helps." Then if you are using the stock ecu, you have to plum it back to the turbo intake. I still don't understand the principal of this from a fluid mechanics perspective, but it obviously works. Seeing as the BOV should be at the intake plenum then plumbing to one turbo or the other should have almost NO differance to the total air flow through the system at the engine as the whole intake line will be at the same pressure and so should not alter the air/fuel ratio during shifts. The turbo shaft that is having air to it MIGHT spin slightly faster than the other shaft, increasing the pressure it can output at when the throttle opens and exhaust flows to the turbos but i'm not too sure if this would be a problem. If you're not running the stock ecu, why not just plumb to the exhaust or vent to atmosphere? Much easier and less complications. http://forums.hybridz.org/attachment.php?attachmentid=14036&d=1242351415 That is a mates rbz plumbed back to one turbo so perhaps it's not a problem

Sigh... Any english speaking posters?

Isn't the whole point of a BOV to release intake pressure.... Hence, wouldn't it make sense to dump it to the exhaust... Correct me if I'm wrong but i get the impression you want to plumb back into the cold air inlet to the turbo, Yes? If you did that, then you would have a closed loop pressure system and the pressurised air would vent out the air filter.... If you ran to the exhaust, after the turbo's exhaust lines connect into the main exhaust (Dump pipe???), then you would circumvent needing to run two lines. Or even easier than that, just let the thing vent to atmosphere and enjoy the sound

I've tried all sorts of sim games, and whilst they're all fun, this whole "learn to race at home" thing is bogus. Sure, you can learn a track and some good lines, but you DO NOT get the feedback that a car gives you. You can't feel the wheels slipping/sliding/locking, you can't feel how fast you're going, you can't feel how close you are to the limit, you just are so removed from the car. Pretty obvious, considering you're using a computer, but i still think that the learn-to-drive spin is a bit much. Don't get me wrong, I love sim racing, and it's a good way to have abit of fun. But it just doesn't compare to the real thing. Personally, i'd rather save my $160/yr subscription and buy another racer/sim with better graphics...

Any L-series bellhousing will fit on any L-series motor. That's about the extent of my knowledge i'm afraid.

Any chance it's hosted anywhere else? I get an error message "you can only view this if you live inside the US" ......

Cheers Flexicoker! The gearbox guy said the shaft would bend and twist, I figured that this would put the mesh out and would be bad. No good about it. Well armed with everyone's ammunition I went in and spoke to the machine shop. When I originally got them to do the work I supplied a photo of a completed bellhousing (http://home.comcast.net/~zheimsothtn/Transmission2.htm) that had measurements on it. I told them to ignore the measurement of the bearing and said that 'this one' (i supplied a bearing) should fit in this hole, but total work should look like the pic. They promptly forgot that I said ignore the gear measurements and went by the directions on the photo and put a 4 tho clearance on the bearing. My fault for not crossing it out I suppose. They are going to score the bore on the bellhousing to reduce the clearance and reccommended I use locktight to hold the bearing in. I also supplied a new bellhousing and they are doing the work again with proper bearing clearance (0) this time. Total cost for new bellhousing and scoring the bore $100 less than the original bellhousing. I'll use the good bellhousing and sell the patched one to someone who isn't racing their car. This is my first project on the car without outside assistance from my old man, so if it costs me $200 on a $1200 project to learn these leasons then I guess it coulda been a lot worse. Thanks again for the help guys! Tom.

Ok, well before i go in tomorrow and make a fool of myself is there any other reasons why a bearing shouldn't be this loose? The gearbox guy was saying (and it makes sense) that the wobble would allow the shaft to bend and twist under load. The gears are essentially trying to push themselves apart with the force from the motor and this wobble will allow the shaft to twist. This would allow the gears to come out of mesh and they would literally eat themselves apart. Is this possible or rubbish? Sounds feasible to me... Tom.

Cheers dan5138. I'm not too comfortable with glueing the bearing in to be honest. Certainly sounds like it's too loose though. Oh well, I will speak to them on wednesday and see what they have to say.

G'day, I'm in the process of putting an nissan 'C' box in my car and I have had the counter shaft bearing hole of the 'B' bellhousing bored out to fit the larger bearing in the C boxes. I just picked it up from the machine shop and it seems like it has a LOT of play for a gearbox bearing. It slides easily in and out of the hole, you can wobble it slightly, however there is no visible verticle movement. Comparing this to the main shaft bearing (not bored) that has to be tapped in and is a PAIN to remove, I am not confident that the work is any good. However, I am not an expert on this and would like some advice. Do I continue and use this bellhousing, or do I have to get the work re-done by the machine shop. These guys are driveline specialists and they know what the work was for, so one would think they would know what they are doing. However, from my powers of observation this bearing seems much looser than any others I have dealt with in these gearboxes before. Thoughts much appreciated!! Tom.

Armand, too right!!! I almost hit the VB wall in the dipper (massive drop left hander, green walls) in the wet. Going super slow but it just wouldnt turn! Scary. Hence why I never do 100% around there, cause then you would have a concrete barrier for a passenger if you run in to any trouble. Richard, Come on, no backing off!!!! Na, it's a very scary corner the first many laps through it. I tend to drop down to about 200 kph through it from about 230 i was getting leading up to it. As you can see in the vid, this leaves a lot of room on the outside of the corner but it's off the line that most people use so it's VERY slippery and would make it interesting to get back on line and slow down for the next corner. If you do regularity at bathurst i would not worry at all about field size. 60 cars on the track is a lot, but it is 6.something k's long and everyone there is very good when it comes to letting the faster guys through. So long as you're not silly and driving under people as if you were all out racing then you will be fine. The race groups though.... I wouldn't be so keen to run with them, thats for sure

This VVV My Friends is a super charged (well, belt driven compressor anyways) Z with pushrod suspension. What a crazy idea, i wonder WHY they did it that way!!!

Cheers Chrus Yeah it is really good doing this with dad, and not just for financial support I would love to go watch a 12 hour there! but you're right, quite a few evo's. Richard: Oooooh.... tough one! That really depends. If you can, i would say do both and make your own mind up about which you would rather do again Philip Island flows a lot better. It's a world leading race track design and it really shows. it's got fast corners, slow corners, banked corners, long straights, the works. Whilst Bathurst has all this too, it's more just a stretch of public road that happens to be a really tricky race track. The lack of run-off at bathurst always means you're not quite going 100% and you gotta be aware that EVERY corner on the mountain is blind, often off camber. For adrenelin, Bathurst. For flowing, proper racetrack, PI. Personally if i had to choose ONE track to do again, I would probably do PI, but i prefer the technical side to the track a little more than others i think. And the extra safety of large gravel traps helps the nerves and confidence a bit too. My Youtube account has in car vids from PI on it too if you want to have a look.

Last year the old man and I took my 260z over to the other side of the country to compete in Regularity at New South Wales' Mt Panorama Raceway in Bathurst. The track is over 6km long winding up, down and around Mt Panorama with a 1.6km downhill straight and a similarly long uphill run. Over the years the track has become known as the most dangerous in Australia with many, even several in recent years, losing their lifes on the trecherous run across the mountain. The particular event we compete in is held at easter time and we compete in regularity. We had so much fun that we decided to go back this year. I, however, became snowed under with final year chemical engineering assignments and tests so i was unable to go this year. Therefore, Dad decided to take his car, a Jap Spec 1993 Toyota Supra TT, to compete in. Here is 1.5 laps comparing in car footage from the two cars. From the video description: Taking footage from 2008 and 2009 Dad vs Son 1977 vs 1993 Datsun vs Toyota Japan vs Japan Classic vs Classic 180 hp vs 330 hp 1.5 laps on over 6km of Australia's greatest Racetrack comes the ultimate challenge. Who will win. The Datsun with its 300 kg weight advantage, along with semi-slick race tyres has it around the bendy bits, whilst the extra 150hp of the Toyota lends it weight up and down the straights. The ultimate showdown. 1977 Datsun 260z driven by son Tom, 1993 Toyota Supra mk.4 driven by Dad John. It had to come to this Dadson Racing Showdown - Dad vs Son - Toyota vs Datsun In defense of the Supra, it should be noted that this is a standard supra, Aero top, Auto, Big Brake package, high flow intercooler (no front mount), big exhaust, on road tyres, whilst the Z is a streetable race car with big brakes, race suspension and semi-slicks. If someone could teach me how to embed the video properly, that would be great

Yeah it seems like a reasonable price. That and i reasoned with myself that i'm not breaking boxes from harsh use or excessive power, just old components, so $500 saving on the box is $500 in my pocket with any luck... Or just somewhere else on the car A mate of mine used to have silvia's and thats all he sold his box for so it was the number i had in mind when i was haggling with a few guys. I also managed to pick up a New In Box nismo shifter for $250. Kinda had to buy the shifter as well to get the guy to part with the box, but I wanted a short shifter anyways and i've heard really good things about this model. All in all, it's going very smoothly at the moment. However, Murphy is never far away with these things, so time will tell Only thing i did differant to your build was to enlarge the countershaft hole to fit the larger C box bearing. I figured that if i was going to do it, i might as well do it properly and that i might as well use the proper countershaft bearing. It's a $250 job to get the hole enlargened though so i'm not yet sure if it's worth it, but the zed guy and myself decided jointly that it would probably be better and potentially cause less issues to use the larger bearing. He mentioned bearing strength and gear movement as his main issue with using the smaller one. Looks like you've not had any problems with yours though, so maybe a bit of overkill to bother with switching the bearing over.

Hey Dave, I've come across your tutorial in a few places (here and NZ forum??) and have it in my bookmarks. Pics is the only real thing that is missing from yours, it was very useful otherwise. Ive got an s13 SR20DET box for $150. Was going to go s14 or rb20 but the only ones i could find locally were $600+. The s13 and s14 boxes are identicle ratios. Only thing they might be is the s14 might be a later revision box witht the even larger gears and dual syncro 3rd. The engine builder is our mechanic. He does pre/post race servicing and just put the wrond oil in the box. The gearbox guy is the local zed expert and wrecker and he changes syncros and rebuilds the boxes.

Wow, Cameron that looks good! The thing about the inspection lids is that the air flows off the bonnet around the windscreen at that point so it's not a high pressure area, therefore in action these should work really well! Have you done anything about stopping water coming in through the vent though? that's the side with the brake booster and clutch master cylinder is it not? Make sure you keep us informed with how it goes. Richard, My car is a little more of a road car than yours and the vent locations im thinking of put the vents directly above the alternator on the drivers side and the distributor, MSD and carbies on the passenger side, so it's a bit more of an issue for me.

Well I’m in the middle of my mid semester uni break, and sure enough, plenty of work is happening. I've sourced a gearbox from an s13 silvia, a bell housing, a bearing for the countershaft so I know how big to bore the hole, and a drive shaft from a 2+2 that I can molest. The bellhousing and drive shaft are at the machine shop as we speak and should be finished by friday. The gearbox is coming out of the car next wednesday and then ANZAC weekend (25-27) the gearbox swap should happen. Everything seems to be going well at the moment, it's been a lot of mucking around as no one can DEFINITLY say about MANY issues with these gearboxes so I’ve taken it in to my own to do a lot of the research. When I have the box in the car I plan to do a big write up with LOTS of pics and to state and CLARIFY many of the questions about the 'c' boxes that it is so hard to find answers for, such as lengths, ratios and components. It's by no means a final stop for some issues as I don't have access to every type of 'c' box that Nissan made, but certainly it will answer many questions that I had trouble with whilst doing this install in an effort to hopefully help anyone else who is interested in doing it in the future. Keep an eye out for my thread, although it will be a few weeks away yet. and NO, unlike many others I won’t be forgetting to do this write up. I promised the tranny guy (the z wrecker/expert) that I would keep him in touch with the swap and give him the write up once done so he can sell these gearboxes as a package instead of just upgrading synchro’s on the old zed boxes and having them fail constantly. I have been working with him on researching the install and he is donating parts and time to help me with it.

Wow, sounds very promising. Not having alot of success finding time to test vents on my car but I am thinking of putting flutes in the bonnet, next to the bulge on either side, perhaps 30cm long on each side. Then also some flutes on the inspection hood covers to help air flow past the carbies. Another point of interest from reading the tunnel test data is the high pressure in the wheel well. If anyone has seen an XU1 torana, they have fluted vents behind the wheel, so i was thinking of doing that to help air flow past the rear of the brake discs. Thoughts? Pic: Richard, what have you done to the vents on your car to stop water ingress when it rains? That's a problem i've been thinking about a bit lately. Have a few ideas but haven't done any research or testing as such yet.