I have an '03 with an FP WR8 turbo which came with 10.5 hotside and their upgraded wastegate. In doing some tuning, now, I realized I wasn't hitting peak boost (22psi) until 4800 rpm. I've used my Hallman Pro RX to adjust peak to that number.

I adjusted the wastegate actuator arm, turning it 2+ turns. Now peak hits around 4000 rpm. However, even without touching my MBC, peak is now around 24psi. I'm of the impression peak should be hitting around 3300.

I'd like to adjust the WGA further, however, if I can't turn down the peak in doing so, I don't want to change it.

Any ideas/input on how to lower peak boost point and still be able to manage the peak psi itself?

Thanks.

 

Peak boost sooner than the stock turbo? Peak boost should be between 4-4300rpm on a stockish turbo. Stock starts spooling @ 3500...so. How can you have peak at 3300? That would be nice.

 

My mistake, perhaps? I thought that's when it hit, in the 3000s?

 

If that's the case, perhaps I've turned the WGA arm too far?

 

I turned it back one full rotation and psi seems to be back, however peak hits much later.

So, I've turned the MBC all the way down. Peak on just the wastegate is about 17 and doesn't hit 'til about 6K!

After she cools off, I'll start adjusting it more.

 

WGA arm adjusted to yield 19psi @ over 6K. Obviously the adjustment doesn't help achieve peak any sooner. Turning up the MBC at that point yields 23psi with a slight creep to 24. 23psi is hit pretty much right at 4K. I could adjust the WGA down to eliminate a pinch of creep, it seems. But, if she's running that boost w/good AFRs I may not.

 

Why such low boost?

 

93 octane WR8 in the process of tuning. She'll go up if she can take it.

Where would you like it?

 

What others mods do you have? It's where ever you want the boost. I don't care if your run 15psi. You have a bigger turbo, i'd want to see minimum 25psi....depends on supporting mods.

 

She was running 25psi before on a crap tune. I somewhat expect 25 on 93 w/BR intake, deluxe fmic, IC piping, SS O2, 3"TBE, etc.

 

ECU controlled boost FTW, read about it and your life with boost adjustments will be cured... I have road logs where I hit a peak boost of 23psi at 3350rpm, just start your pull at 2200 and spool up occurs... in any gear but this pull was in 3rd gear. Im was running on 91 oct when this was done also, stock turbo.

FP green turbo's typically spool up a few hundred rpm later than stock turbo's with ECU controlled boost, so aim for peak at 3800-4000 rpm and start your pull at around 2500rpm.

Good luck!