Hi, just some days back made first pulls on a S2000 turbo i did, everything looks good but car is boosting 16.8-17psi! it's a turbo kit i did using 6262 precision turbo, Tial new brand bov and mv-s external wg. ok, just intalled white and green spring as tial spring sheet shows..

http://tialsport.com/documents/MVSprings2.jpg

but i dont know where's the problem, it should boost around 11-11.5psi ..sent an email to Tial with not reply yet..any input? thanks in advance!

W.R

 

Tial is MV-S model!

 

Which manifold are you running and do you have pictures of the wastegate placement on it??

 

Short runner manifold with a big turbo running low boost (and yes 11 is low on such a big turbo) will require a bigger wastegate or better wastegate priority.

You're trying to make sub 400hp on an almost 800hp capable turbo. Unless you plan on building the motor for more power to fully utilize the size turbo you have you need a much smaller turbo.

 

It's a topmount manifold i made.

 

Wastegate priority looks on point.

What are you doing for boost control/pressure signal?

 

i installed AEM tru boost, just dissabled because i had similar problem in other build i did using K20 w/ 3076R and was EBC, this time looks problem with tial springs..checked again and it should be boost up to 11 psi, i think i will remove green spring and leave white one and see what happens..

 

Actually the port doesn't look tear dropped at all. Is it? That would make a difference trying to control that turbo.

Also, just going to leave this here for people's reference:

 

sorry for my english but i dont understand what exactly you means with port..

 

What he's saying basically is that your combination of wastegate size / spring rate / exhaust manifold configuration in relation to the size of the turbocharger is causing the problem, even if you have the correct springs.

Basically, you're trying to get 11psi out out of a turbocharger that is not efficient at that level with a small Wastegate like your MV-S. The fact that you're using a turbo that has 20lbs/min more than your older GT3076R, and trying to get the same amount of boost pressure is not going to work well.

In effect, this combination will cause what is known as "boost creep" where the exhaust energy volume is more than the wastegate opening can handle. This is especially true on the Top Mount manifold you're using which is made with larger 1.75 runners for top end power at a high volume.

The turbo wants to do more and the smaller wastegate you're using can't stop it.

Time for a larger wastegate and a boost controller to help.

 

thatswutimtalkinbout


Thank you Sir!