Boost surging? .... 951 questions

ae1969 · 05-12-2003, 06:16 AM

So I finally got the 951 put back together.......

I have a couple of questions.

1. Turbo Timer : does the car need to be running a certain amount of time (or temp) before it kicks in. I have heard it a couple of times.... but I am pretty sure I took it for a short hop and did not hear it kick in?

2. I have a lindsey racing wastegate, profec A, stock turbo (i think). I am in any gear and I floor it........ I see the boost guage read about 8-9 psi...I pick up speed..... and then all of a sudden it jumps to 15-17 psi on the gauge (nice kick in the ass). Why would this be happening?...... The turbo spools quick to 8-9 then it keeps accelerating....and then all of a sudden 15-17 psi...

Thanks

****AND DOES ANYONE KNOW HOW TO SETUP THIS PROFEC A, OR HAVE A MANUAL!!!!!!!!!!**** I WOULD GREATLY APPRECIATE IT***

AFJuvat · 05-12-2003, 06:25 AM

Time: No, it should start pulling boost from the get go - usually best to let the car warm up first though.

Profec A: Sorry, I have nary a clue.

AFJuvat

ae1969 · 05-12-2003, 07:24 AM

Mother Juvat....

That turbo timer...that flows coolant throught the turbo after you shut it off? Does it always turn on? or does it only come on at certain engine temp? I did finally find my mysterious coolant leak and it seems to be coming from that timer, valve, watchamacallit??? I dont have any coolant leaks....... .and then the timer kicked in and out the coolant comes??? I have too pull the airbox to get a better look. I may have to replace it.

About the boost surge...Yah.... I didnt think the boost surge was normal....
BOY can you tell the difference between 8-9 psi and 15-16!!!! That profec A controller has these micro-mini knobs on it????? whoever designed that was a moron!!!
On a side note the A/F meter showed good ratio thoughout the rev range even with that sudden 15 psi ..........

What would normally cause a surge on a stock turbo?? bad wastegate??

Scott R · Scott R's Garage

I have the same wastegate setup that you do, and I think I can lend you a hand, couple of questions:

How is you're manual boost controller hooked up? If it's done correctly the cyclic valve should be completely bypassed, and the banjo bolt line re-directed to the MBC. If the cyclic valve is still in the circut you can have this lag-boost condition.

Secondly, what is the condition of you're banjo bolt fitting? Any cracks in the rubber hose?

coupe · 05-12-2003, 09:02 AM

Hi there. The Turbo timer that was on my 951 is manual and I set it for 1 or up to 5 minutes, and it keeps the engine running, for the pre-selected time interval, while I step out lock the doors and walk away. You are probably talking about a more modern Turbo timer. Worth a shot..hhehe

ae1969 · 05-12-2003, 10:02 AM

Coupe.... uhmm you can actually set the timer on the pump? Uhmm go figure.

Scott .... will get in there and take a look at it.... I'll report back later. Thanks.

ae1969 · 05-12-2003, 05:40 PM

OK guys ... here are a couple of pics....

1. Ok the blue hose which supposedly goes to the timing cycling valve....(whatachamacallit)..... is burnt on one end??? Whats weird I CAN'T see where it attaches????? I pulled the air filter housing of and it was just hanging there?? HELP...I looked at the parts diagram but its a plumbing nightmare. I am assuming my timing valve was removed when the Profec A was installed since it was supposed to by pass this???? So where does this hose go?

NOw I get 8 psi only...... and it just dies around 4000 rpm

2. What is the brass fitting in the other picture???

Scott R · Scott R's Garage

OK, bad news is that the timing valve is under the manifold for the most part, between #3 and #4 intake runners, but you can bypass it without removing the manifold. On my Lindsey setup the line your're looking at is capped off per their instructions, check this link it will clear it up.

http://www.lindseyracing.com/boost3.htm

At the bottom of the page is a link to the install instructions, the last page shows you how to correctly by-pass the timing valve into the MBC. In fact I don't have the timing valve hooked up at all and it works awesom!

ae1969 · 05-12-2003, 09:49 PM

Thanks scott...

Looks like mine was completely removed (cycling valve)...can't see it under the intake.....

Also.... I removed the blue line and capped of the intake hole it left..... and she is pulling at 11 psi now (when I have my profec set at 1.0) ....

If I dial it up (1.2-1.3)..... Once I floor it jumps to 11 psi at 3,000 rpm..........and then surges to 15 psi.....past 4000 rpm........

Does it seem like its working properly now? Or should it actually be pulling 15 psi from 3,000 rpm to redline......?

This was all done at WOT in 3rd......

Thanks!

very~worn~944 · very~worn~944's Garage

If i may ask..how much did you pay for this whole setup ae? i am curious cause i am looking to buy a wastgate/controller/boost gauge/a/f monitor/etc. My stock wastgate MUST be leaking to cause the lag and noises i have. I have bad lag. As far as turbo timers go...you guys confused eachother. The car comes stock with an electric coolant pump that will run for 30 seconds after you turn the car off if the turbo is over a certain temp. I have come to decide that it is random...cause if i have been driving the car for a while...it will always come on when i turn it off..but sometimes when it is cold i will fire her up...turn her off..and it will go on...others..it won't. A TURBO TIMER is a device that will keep the car running for a set time after the owner has walked away...to keep oil and coolant flowing till the turbo is cool...This keeps oil from cooking to the sides...Fun trick...drive your car like a bat outta hell at night then jump out to see the whole headers ...the whole turbo...and the pipe inbetween glowing BRILLIANT red. not wussy maroon..but sunset blazin red. I could read a book by that light...now imagine if you shut off all source of cooling to that red hot chili..hehe. not good. Keep in mind..not only does the oil and the coolant cool the beast...but the ambiant air rushing in and being spun around actually cools as well. When you turn it off..you get no oil or air going through it, hence the coolant pump. This is why most people let there cars run for about 3 minutes or so after driving them...to let it calm down..not to listen to the end of that good song on the radio. By the way guys...is our fuel tank pressurized? I was told i should hear whoosh when taking my cap off...but my cap doesn't seal...bad?

XJOSHX · 05-12-2003, 10:32 PM

hey Alex, got any pics of the whole car???? Did you ever tally up how many days it took to get it???

Scott R · Scott R's Garage

Sounds right in line Alex, 3000 at WOT should be your highest boost level, just to be sure take it on the freeway and get it to 5th gear at about 65 or 70 and hold the accelerator down, you should be able to peg the factory boost gauge.

ae1969 · 05-13-2003, 09:48 AM

Joshx...... uhmmm number of days..... lets see...... I told him I would buy it Dec 20, 2002.......... Did not receive car until ~April........ so it was a while

Very~worn....The car came with the profec A, lindsey racing wastegate, and lindseys A/F monitor... It all came with the car so I am not sure what it cost him. Now that the intake leak is fixed it seems to work really well. My next step is Vitesses Stage 2, bigger intercooler, 55lb injectors and some new intercooler pipes. In a couple of months I will probably trigger those purchases...
That will keep me busy this winter! This wastegate is very popular and so are the Tial ones. Unfortunately I couldn't tell you which one is better.