hey guys, im just wondering what kinda boost you guys are seeing? ive got a S4 Tii, full 3'' exhaust,ported wastegate, intake, and stock turbo, no boost controller, just a line straight from the turbo. and just wondering if your boost is falling off? ive heard of people creeping, i dont have that problem, my boost hits about 11psi until around 5krpm, then it falls down to about 8-9ish. im guessing its my ported wastegate. im just too lazy to buy a mbc now

-Daniel

 

also, ive heard of some kinda boost controllers you can rig up from home depot, i dont know exactly what this consists of. but if anyone has some experence please enlighten me

 

I see about 9-10psi max after creep at high rpms then it drops around 7000rpm to about 7psi.

You can make manual boost controller from a 1/4" check valve that you can get at mcmaster-carr online, then you need two nipple ends, and take it somewhere to get the nipple ends welded on either side if you or a friend can't do it, its pretty simple, twist right for more boost.

 

What you're describing is perfectly fine. An MBC is not going to get your even boost all the way up to redline. The only boost controller that's going to get you even boost all the way to redline is an EBC (electronic boost controller) with dedicated MAP sensor, i.e. A'PEXi AVC-R.


-Ted

 

i don't understand how some people can creep up to 10 psi and you're having a problem keeping it. sounds fishy. i have a little done to mine and mine stops right at 5.5psi and starts creeping around 5k. i think there is something wrong with your turbo. i thought these things were supposed to be able to boost 13psi, or more, till redline.

 

hell, i bet if a took off my wastegate line, i could easliy hit 20psi......once all the way to redline. but i hit 11psi at ~3k, and keep it till 5k, then it starts to drop off a bit. i forgot to add, i have a streetport, thats probally most of the reason the boost drops, my motor really breathes up top.

-Daniel

 

anything over 5.5psi is creeping so you do have that problem

droping is normal

 

I hit about 12-13 psi at 3000rpms then it falls off at about 5000rpms to 10-10.5 psi.

The turbo cannot hold boost above 10~ to redline when your wastegate is ported. No wastegate will create insane creep. Before I ported mine boost would hit 9 and just start climbing. I would have to let off at about 5k rpms cause boost was up to 12 and speeding up.

WOO HOO my 1000th post!