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-   -   Is This Boost Pattern Normal? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/boost-pattern-normal-692188/)

85rx-7gsl-se Sep 27, 2007 02:30 PM

Is This Boost Pattern Normal?
 
I have a quick question about my car's boost pattern. I know this is kinda a noob question, but I will ask it anyway. I have an S4 JDM TII in my FB. Running stock SE 4.08 gears with a TII trans. In first gear the car will pull about 4-6 PSI, 8-10 in second, and 12-15 in the rest. Is it normal for me to only be able to get the full boost in the top gears? I am currently running a stock wastegate and wastegate port, so my additional boost is the result of boost creep(Running standalone so not really a problem). Would porting the wastegate and then adding a real boost controller make a big difference on my boost in the lower gears? Thanks in advance.

boost_its_what_for_dinner Sep 27, 2007 06:59 PM

well 1 your car is really light.
2. 4.08 gear is quick (not much load on motor)
3 porting the wastegate and adding a real boost controller will help stable off your boost.

josh...just josh Sep 27, 2007 08:30 PM

well it isn't a problem for fueling with a standalone, but 15psi is too much for the turbo, you're just blowing hot air and it's going to kill the turbo. port it and run 10psi or upgrade

hurleysurf24 Sep 27, 2007 09:42 PM

yes ... higher gears are where the engine breathes more and allows more boost

SpeedOfLife Sep 27, 2007 10:19 PM


Originally Posted by josh...just josh (Post 7375742)
well it isn't a problem for fueling with a standalone, but 15psi is too much for the turbo, you're just blowing hot air and it's going to kill the turbo. port it and run 10psi or upgrade

yeah, boost controller and ported wastegate are your next things to easily get the most out of every gear.

85rx-7gsl-se Sep 27, 2007 11:11 PM

I see what you guys are saying. I figured that porting and a controller would be better, just wanted to verify and see if you guys agreed that my setup is causing my issue. I have just set up a two-step on my Microtech so that should help get some more boost in the low gears until I do the porting.

arghx Sep 28, 2007 09:09 AM

The problem you may encounter with an undersized wastegate (this is what I ran into) is that you will have random crazy spikes when the weather gets cold. I was hitting 20psi when it was 35-40 degrees out and like 12 when it was warmer, like 60s + . I have a big streetport and front mount though.


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