Ehren79

I'm having trouble with overboosting when using the Profec A boost controller. With the controller off I run about 6 psi and "usually" I run a consistent boost of maybe 8 psi with no drop off or overboost with the computer on, but after I've been running it hard the controller wants to let it boost infinitely. I've adjusted the dip switch on the back to the "when overboost occurs" setting but it still overboosts occasionally. What are the correct settings for the dip switches? Should it be set for "actuator" or "wastegate type" on switch #1?? Right now I have #4 up and #3, #2, and #1 all in the down position. Any help would be greatly appreciated. I'm new to the world of turbocharged rotaries, much experience with non turbos though. Thanks.

RETed

What kinda exhaust do you have on the car?&nbsp If you have an open exhaust, boost creep will cause the GReddy PRofec A to barf.



-Ted

Ehren79

Yeah, that could definitely be the problem. I'm running an HKS catback system (3") and an HKS downpipe. I think the cat is gutted too. Weird thing is that it only happens rarely and only after i've been running it hard for a while. I'm probably going to go with a high flow cat instead of just the empty shell cuz i'm getting some wicked backfires with flames...haha, it's cool but a bit annoying and i don't want to blow a muffler. I guess it's something i can live with for a while cuz I always keep a close eye on my boost gauge and the Profec does an excellent job 99% of the time. Thanks for the input.

Ehren79

Also, Anybody know the correct settings for the dip switches on the back? I'm assuming they're set correctly but Profec's manual is a bit fuzzy on the details. The "actuator" setting for switch #1 is correct for an internal wastegate correct? And the "wastegate" setting implies an external wastegate and not the stock setup correct?

BlackDragon

Well I'm going to have those same exhaust mods. How can I prevent the boost creep then? Different controller? What can I do?


Edit: 89 TurboII

RETed

Boost creep can be minimized by porting the wastegate.&nbsp The Kouki FC turbo can also be made more efficient by "banding the wastegate flapper" so it can open wider - this is a bit hard to explain in text, but once you expose the wastegate flapper, it's pretty straight-forward.

You can also "clip" the turbine wheel - this reduced efficiency of the turbo at the top end.
http://fc3s-pro.com/TECH/MODS/TURBO/clip.htm



-Ted

BlackDragon

Thanks for the FC3S pro site. Didn't know about them. Also, are you on AOL AIM Ted? I'd love to chat with you. I'm always online.

Maxthe7man

I had the same problem, I did not get boost creep with the profec disconnected, so that rules out the wastegate, I have no cats, just 2 rear mufflers and stright pipe, I also have a tid mod, no acv, no air pump etc etc. The profec works better if you observe your boost with out the profec in the loop. and then set your profec with a hand pump, it lets you get the boost threshold more consistent during setting.
Also, if you have 10 miles of vaccuum hose connecting it to the wastegate and manifold, that really slows the resposne time of the profec down, keep the hoses as short as possible. Max

RETed

AIM nick is in my profile...
I'm also always on IRC EFNet channel #rx7...

Give me a couple hours right now, as I need to go to a job interview soon...



-Ted