david fracolli

I have been playing with the car off and on for the past couple of weeks as weather permits. One day it is 50 out and the next day it is snowing!
I have a SFR stage 1 turbo with guru chips and a mafterburner. SWhen i first started playing with the car it would hit boost very hard at just below 4,000 RPM's and break the rear end loose. Maximum boost was 15.4 PSI. Now 2 weeks later the car will not boost above 15.4 psi no matter what I do and boost rolls on instead of suddenly hitting like it did before.
I have a stock wastegate that is shimmed and has almost 190,000 miles on it. I would really like to be able to run more than 15 PSI of boost but it appears that the stock wastegate is bleeding by thus not allowing any more boost to build up.
Before I go out and spend $300+ on a tial wastegate i wanted to get other peoples thoughts on what else might be causing the problem.
The cycling valve has been removed and I am currently using a reliaboost to control boost pressure as the solenoid for my profec B failed.

theedge

Pretty sudden failure.... Maybe a hose is split or loose?

Howd your Profec B's motor fail? On mine I found what I thought was a perfect mounting spot. Then I bent the cable. Half the wires snapped, and the sheath came out of the motor housing. I was pretty choked. Crap design and shoddy harness IMHO.

Edit: Wait, was it Profec before, then Reliaboost and thats when it started acting worse?

lart951

I had similar problems dump the stock WG and get a tial 38mm

https://rennlist.com/forums/944-turbo-and-turbo-s-forum/244438-38mm-tial-installed-dyno-chart.html

check post 48 and 49.

david fracolli

Lart, will do. Right now though money is pretty tight. When the company I was working for did not renew my contract I went from making $80,000+ tax free to now making $8.00 an hour!
Brian, as far as the profec B failure goes A piece ofthe plunger inside the solenoid broke off and now it allows boost to get through all the time. As soon as the state of New york decides to return the money it owes me I am going to get a new solenoid and hopefully a tial.

reno808

it could be your blow off valve.

david fracolli

I really do not think it is the blow off valve as it is brand new Forge unit.

streckfu's

Wastegate or boost leak. If the hoses on the intake side are good, it's time to save for a Tial from Pauerman.

david fracolli

I replaced all the hoses when I installed the new turbo and had the head rebuilt. Vacuum at idle when warm is -.80 to -.82 PSI.

five-o

I'm new to 951's and don't have any advice on your problem but I am sorry to hear about your job situation. My police department closed if you can believe that crap. I also took a pay cut but luckily got hired on by another department. Good luck to you.

lart951

David, You will feel the difference with the tial is like a new car, I hope you get your return soon.

david fracolli

It is supposed to get up to the mid 40's today so i think I am going to jack the car up and check for exhaust leaks. i really doupt that I have any large one but I guess it can't hurt to check it out.
Thanks agin everyone!

streckfu's

Negative PSI? What gauge are you using? Vaccum is usually measured in Inches of Mercury (InHg).

If you are confident that your hoses are good, look at the wastegate.

david fracolli

Using the guage on my profec B.

black944 turbo

the reliaboost may not be strong enough either. I have mine cranked pretty far and I am hitting 15 psi. I would take the reliaboost apart and either change the spring or stretch it a bit and see how that works first.

reno808

JUSt get a EBC save your self the hassle.