ok so now its time to put a new tanny in cause the w58 is toast. I need to shift into 3rd from 1st cause secound sounds reallty bad, and at idle the tranny chatters like a disel truck. I think that something happend to the input shaft. But no worries a six speed and parts are on the way.

I just was courios about a couple of things.....has anybody tried going with a six speed and a aluminum flyweel to lossen up a couple hp. I know that this mod in the supra chatters the tranny and it can sound as loud as a disel truck. I was wondering if its that bad on our cars. If it is then I take it the only option we have as to not have this chatter is using the stock flyweel right? Let me know . And the other question that I have is, what cam sizes have you guys tried out. I am looking for a compromise with effciency and more power. I was thinking about a standard spit with 264/272 (intake/exhaust), or both 264's cause I understand that going 272/272 is a lot more lag but a significant top end. By the way has any of you guy tried a reverse spit with 272/264 or using Crower Cams avertized at 276/268 or 272/268 ( this I think gives you less overlap....not sure here is the link http://www.crower.com/cat/import/toyota/camshafts.shtml )where there is more duration and lift on the intake side letting more air in as to letting more exhaust out faster? I have heard by some mechanics that this layout is usually done on turbo/ forced induction cars. Let me know what you guys recommend so my car idles at the most 1000 rpm effciently and gives the most power. Thanks.

Bests,
Adriel

 

I cant tell you how the crower's and or hks are as I havent ran the car yet. But once I do I wil let you know. How much did you get the tranny for? and are you going to also swap out the rearend? goodluck-pdang

 

I got basically the whole drivetrain from the tranny back for under 5k including rear breaks. Yes I am definittly swaping my rear end. I would not do it any other way. Let me know if you find out anything about the cams or the flywheel questions that I asked. Later

Happy Boosting,
Adriel

 

Yes you will have the rattle "ask me how i know " just idle the car at about 1200rpm and the noise is not that bad.The cam issue is debateable some like 272/272 and some 264/264 what size turbo are you useing the 264 intake 272 exhaust seems to be the ticket for the big hp supras Ryan Woon from WOTM recomends 264/264 hope this helps.

 

If you don't want the tranny ruckus then use a new stock dual mass Supra 6-speed flywheel.... Just be careful in your clutch selection, those single disk clutches tend to have very heavy peddle pressure for their pressure plate to hold the power, it's quite a workout on your leg and the master and slave cylinders as well.

Not sure I've ever seen anyone use that reverse setup on Supras or otherwise. Doesn't seem right to me.
264 intake/ 264 exhaust works, and 256 intake/ 264 exhaust has had good results as well. And I know of people getting good results out of 264/272 on really big turbos. The reasoning for the split cams is to get a little more aggressive while still using the similar split method as in stock cams, and keeping with the way the head's flow was originally designed. The exhaust valves are smaller than the intake so longer duration on the smaller valve gets flow closer to the intake. Avoiding overlap is always a plus on turbo cars, keeps boost from pushing out of the cylinder into the exhaust stream before it's utilized in combustion. NAs are opposite, needing the overlap for the exhaust leaving to pull the new intake air into the cylinder since there's no pressure pushing it through...

 

ok I follow what the theman says about cam setup.... I would have to say that you have convinced me not to look into a reverse setup. I am running stock turbos with future plans on going single, with a relatively large turbo setup, but for now I would like to get some extra power with cams and not have to change with going single. Is it wise for me to invest in cam gears right away or can I stick with the stock timming setup with only 7 or so degrees of overlap cause cam gears are an additional 300 bucks and is it going to make a whole lot of difference with the new cams? So I think that you convinced me to go with 264's or a standard split using 256/264 don't know yet but a reverse is out of the question cause now you pointed out the obvious ....the intake is bigger than the exhaust .......so a reverse split would probably give you alot of top end but horrible mid range response.....lag, lag lag..... Thanks angain, any info that you recommend on a clutch?


Thanks again,
Adriel

 

You cant just look at the way the lobs are in comparrison to top end low end as the exhaust valve and intake valves have differrent timming for the aloted applications on duration. You dont want too little air and pushing out too much of nothing----hope you can catch my drift on this. I would consult the head builder with these questions as valve timiing is veryimportant. i would hate to see you buy these cams adjust the shims for them and than have to redo it again. Goodluck.


AS far as the flywheel stick to stock unless you are planning to buy some sort of twin disc clutch which usually come with its own.-pdang

 

What h.p. triggered the failure of the w58? I'm concerned about this after my planned gte swap. I'm hearing that the w58 can handle up to a range of 400hp. Your comments regarding your experience helpful. Did you push past this number?

 

Daveh managed to push his to the limits of mid tens. SO he might be able to help you out with that question.-pdang

 

ok there are a couple reasons that my w58 life came to an end so soon. One of the main reason was the fact the tranny is pretty old 130k+ miles. The dyo barely even showed 400 whp but the torque was 420+ ft-lbs at the wheels and the graph was completely exponetial! After moding my intake to be able to breath better it now has over 400 whp I am sure of it cause it broke a little after I did this mod. At any rate when boost came on the torque shot off like a rocket. I don't think it was the hp that killed it, it was definitly the rapid change in torque, not to mention the stage 5 custom solid iron disk clutch from SPEC did not make daily driving fun. It was really hard to find a clutch in that form factor to handle that kind of torque. So I think that transmisions break because the torque specs are violated. Hp doesn't kill trannys its the sudden change in torque that is the kicker. Think about it when you are accelerating on the highway from a 70 mhp role and you gun it, the change in torque is not sudden, its gradual and hp is what it rapidly changing. But from a dead dig that sudden change that will jerks you back in your seat from a clutch lautch of 3 to 4k. Regardless I knew that this was envitable and the right way to finish the project was use the 6 sp, and that exactly what I plan to do.

Thanks for all the info,
and Happy boosting

Adriel

 

TurboSCLex,

You may not want to waste money on cam gears right now if you're going with HKS or other perf. cams.
Cam gears make the biggest difference on stock cams, since on the aftermarkets' the lobe separation has often been optimized with the new grind. Also if you did buy a cam gear I would only bother with getting the exhaust side. That is where you find the most benefit in adjustments, whereas on the intake side there maybe only a useable 1 degree of adjustment for gains, if any at all.
I too like the idea of spending money where it benefits the most.