Thread: Think I went with too big of a turbo...

I can tell you this isn't true... But what do I know.

I actually have built 4-5 setups utilizing similar sized turbos and protech/various log manifolds. Even one on a smaller T3 with stock cams. All of which have made 260-390hp from 9~20psi.

If the owners want to post they will.

How can you say it is not a tuning issue when he is playing in the blind with his maps?

You are at a different altitude so that doesn't count.

im saying his best option and one of the few without changing anything else in his setup. Its not a tuning thing I can bet you that much.

Lets break this down.

VE with 54mm turbo, log manifold

At 10-12psi his car should be screeming fast if he went with bigger turbine housing and has a good free flowing exhaust, the fact that it obviously isnt shows a problem. Same problem Coheed ran into when running an almost identical setup.

Only way Vadim can make more power is with some slight fine tuning but mainly just more boost which he has been trying and now getting knock with it because there is simply flow problems in the setup. We all know the VE's dont like to be choked up by log manifolds and you can somewhat get away with it with a larger turbine housing but still not completely. He needs a cam with very little overlap to keep reversion from happening. That is a fact as again he is not the only one that has ran into this problem. If he wants to keep this setup his best option is the VET cams. Plain and simple. Not fine dyno tuning, same tuning that he can obviously feel, hear, and see on the logs doing it on the street.

Again prove otherwise with a very similar setup to his and we will talk.

I keep on forgetting everyone is the expert these days.

As far as dyno time with VET's it is not fair to say NO ONE has put in more time when you dont know.

Just because it is not posted here religiously does not mean its not done. Again what do I know. My VET along with the others have been together for 4 years+ and has seen every bolt on there is while being constantly abused @ 300-500hp.

If tuning is not the issue maybe that will explain why this VET is still on its original piston set while others in this discussion have melted a set or (2).

Shout outs to FL on this one.

You guys keeping holding it down with the VET's.

Im done.

Again thats irrelevant. Tuning is a great tool indeed but it can only do soo much. Just like when I was pushing the T25 to its absolute limits. No matter how good of tuning is done, You push a T25 to its limits to where your getting a massive amount of backpressure causing reversion you will get detonation no matter where your timing is, not matter how much you richen it up. You will have detonation. I found this out the hard way after 4 motors cracking ring lands. 11.2:1 a/f across the board and timing backed down way more than should have been. Still happened. I may have blown up motors but it was a learning experience. As far as my T3 setups go. Motor is the same motor thats been in the car for going on 3 years now. Difference was that I had a much much better flowing setup than vadim does. Didnt run into reversion problems.

Vadim has done logs again low cams vs high cam and no knock on the low lobes where this little overlap and knock on the big cam. That right there tells me backpressure issues. Its not rocket science. Coheed has done the same thing. Testing after testing. Im not saying others havent done testing. They just havent been as willing to share results. Not saying they have to share exact tunes but all they could say is made this with just basic tune and then made this after tuning no changes and all detonation gone. But hasnt happened yet.

Im not doubting you man, you have done some great work but not every setup is created equal. Vadim is obviously having the same problems coheed ran into and has tried everything he knows how to try and tune it out where as coheed was on a JWT ecu. But that really shouldnt matter. Fact is Vadim has tried to do what he can tuning it out with zero success and i know he knows what he is doing.

I agree with sr20GTi-R.... you need to get it on a dyno..... The last time I was actually at a dyno with a t3/log/ve setup was before this forum even existed. Something must have changed since this forum came about, now they don't work anymore. Like I said I don't save other people's dyno charts from years ago just to justify what I think to the forum. I have said what I need to say about this, take it how you want, I don't care. When I suggested to keep the stock pistons, I suggested tuning the car on the dyno. They will last IF TUNED CORRECTLY!
Drew

His power goal has been reached reliably with similar sized turbo's already.

Did he log where he was getting knock on the high cam? It would be nice to plot AFR/TQ at that point while looking at the timing map.

Back pressure is one issue, I do agree. But that is not what is stopping him from his power goal. It has been done.

All I can say.

Your right he was probably getting knock at peak torque or around that area and i believe he mentioned that. Another thing he mentioned was that he was only reving to 7k which even with his setup he can make power holding to 8k and wont even peak power until probably 7500-7600 or so. So thats another thing.

Im not dissagreeing with you on anything. I think its just safer to say the VET cams will be more reliable, easier to tune for more power without having backpressure issues and also allow him to up the boost more if he wants again without running into problems.

Detonation likes to occur at peak torque for the most part that is known especially with crappy flowing setups.

So we can agree on some things and 20ve cams can work, he just needs to focus on more topend power than mid range. He is just not gonna get the midrange he is looking for without problems with those 20ve cams. VE is all about topend anyways. lol.