I have a PFSC ported motor with a DB, high flow cat and RB CB. I just installed a pettit ecu and a boost gauge. I'm hitting around 12-14 lb of boost when I open her up and run through the gears. my problem is when I'm in 4th gear at about 3500 rpm's and I give it gas. It boost's like 16-17lb of boost!! I have the HD boost controller and it's about half way open. When I open it more I only get like 8lb of boost when I'm running it through the rpm range and still get 14lb of boost in 4th at low rpm's. Why does this happen?? If I get a profec B electric boost controller will it let the boost go up to and stop at 14 lb at high and low rpm's or is it just like the HD one?? Does it ajust on the fly is my question I guess? Could it be my wastegate's not working right??

 

I assume from the HD boost control valve you removed the pills, if so you've probably reached the mechanical limits of the stock wastegate <ie the hole's too small> with your mods list its quite possible you need to port out the wastegate...

 

But if its holding 14psi average in all other areas just get a boost controller and it will be set...

 

What is involved in porting the wastegate?? Is it something I can do myself. Is thier any info online about how to do this?

 

It does fine when I'm in high rpm range but when I'm at 3500 in 3rd or 4th gear it hits 16-17. Will a profec-B let it still be at 14 lb at high rpm's and keep it below14 at low rpm's or would I have to go with the e-01 ??

 

You don't want to be hitting high boost like that on the pettit ecu.
Stick with 13 on the street and you should be fine. Cam suggested 13psi as the most on the street (actually I think he said 12 to be safe)

I have about the same mods (+midpipe and fuel pump)and same problem as you but it happens in 2nd gear for me and I am non sequential. If I go through the gears I will get about 11psi but if I am just in 2nd gear at low rpms and floor it I will get 15+psi I've seen 19 even. When I do the same in 3d or 4th I get 10 psi and 9 psi respectivly. I also am using HD valves and have now set my boost to 9.5 psi and I get some creep to around 11psi in 4th gear around 6000 rpms. I'm pretty happy with that but I'd be happier if I could get 12.5psi in all gears and have it stay there. The HD valves are **** IMO.

Take out the pill and open up the HD valve all the way for the wastegate line until you get a profec B. I believe this will solve your problem and mine.

Snook

 

I dont think any kind of boost controller is gonna help either of you, and running absolute minimum boost kinda short changes yourself but it does lower the tendency of the gate to not open quickly enough when you put the car under heavy loads like hard acceleration at low RPM. Personally I wouldn't play around with this and I'd do the porting, you can do it yourself but its not easy, its best to take it to a machine shop for the actual hole boring and then smooth in the rear area with a dremel or the like to get good flow, then your boost should be much more stable. seeing 16-19 psi spikes im suprised you guys havent already tossed Apex seals

 

I think the electric boost controller will work especially for him with a high flow cat he should be okay with controlling boost.

it all depends what kind of motor you have. My last motor "rebuilt" by a local shop blew after hitting 13psi for the first time in first gear with my identical setup as now. Then I got a pettit motor and I've run high boost occasionally for months now and its fine. I'm sure if we didn't let off the gas when we see 15+ boost then the motor would blow. It happens when trying to tune the HD valves that's why they suck so much.

 

My motor is a ported rebuilt Peter Ferrel motor. Looks like I'll be getting my wastegate ported and an electric boost controller. Let me dump another $6-800 into this beast!! Does it ever end?? Is their a link anywhere on porting the wastgate??

 

trust me you don't need to port the wastegate especially with a high flow cat.

Get a profec b for around 300 and you'll be happier then ever. I'd set it at 12.5 psi for the street as your max boost if you have the pettit unlimited boost ecu.

 

Could it be my boost gauge is off?? I don't see how the 1st turbo could even boost 16 lbs. because it happans between 2000-3500 rpm.

 

Someone suggested drilling out the pre-spool pill. Will this help?

 

Ditch the "Home depot" valves. Put the stock pre-control pill back in and install an electronic boost controller like the Profec B. It will provide more consistent results. Give this a try and see what happens.

Also, have you verified that the line from the primary turbo to the pre-control actuator is actually connected at both ends? It sounds like your pre-control is not activating properly.

You DO NOT NEED TO PORT YOUR WASTEGATE! You will not get boost creep with a hi-flow cat on the car. This problem is not boost creep.

 

Thanks rynberg, will do.

 

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