Most psi seen!! a 2.5 block take?

[perfectchoicemotorsports]

What is the most boost or psi, anyone has seen on a dyno run or boost guage, for a 2.5 liter block either Turbo or modified NA block?

Kevin
PCM Injection

[wolfrpi]

24-25 briefly

Erick

[perfectchoicemotorsports]

Wolf:

Was that boost or Absolute pressure?

Kevin
PCM Injection

[Macabre]

I've seen 20psi boost. 20-24psi absolute would be stock or less so I'm sure that means boost.

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'86 951 Graphite Metallic/Tan

[adrial]

I know someone in Florida that runs 22psi in a 951...he knows someone that runs 40psi + NOS....
the 22psi car had a O-ringed head and wide fire headgasket...not sure what other engine mods. The 40 psi I have no idea.

[dan10101]

I've seen 21psi briefly with a stock block 2.5. I usually run 18psi. Currently working through the startup bugs on a new APEXi AVC-R boost controller. So far the most I've been able to get out of it is 17.
Give me another week or 2 and I'll do a writeup on it.
DanD
http://www.Boost-O-Holic.com

[seb928s]

Since we are on the boost subject what is an safe boost to run in an 951, that is stock no new gaskets or stuff like that?

[951carter]

you cannot raise the boost w/o chips or the DME will cut you off. With just chips i would advise @ 15 psi. I have run 24 psi before with a wide-fire gasket and a shaved head which raises compression slightly. All internals were stock at the time.

[89-944NA]

I hit 28.6lbs (hi boost recorded on my AEM tru-boost), running a k27/6 on a turbo s with stock internals, wastegate stuck closed. Damn happy I didn't send this engine over the rainbow bridge though. But damn, that was one hairy ride for a few seconds.

[944chm944]

someone here in colorado was running 30+psi on his old 2.5 engine

[zedsn]

I ran 20 psi boost briefly with autothority maf, autothority chips, stock fpr and stock injectors and it was fun. I do run 15 psi with a 3 bar regulator and performance chips for everyday driving.

[running_cold924]

also what are you running? 93? 101? 118? E85??

[zedsn]

At 15 you can get by with 91 but I don't chance it and run 93 always.

[PAUERMAN]

I run 1.5 bar (22 psi) daily and have been for the past 3 years. I use E85 fuel and my Vi-PEC engine management kit. Absolutely no problems and I know it will take more boost without any issues.

[rick13]

somewhat off topic. i personally witnessed 40psi on my fathers 2.3 liter Ford Mustang SVO. it had a cast iron block, head, and forged pistons...some multi-layer steel head gasket too.

somethings you never forget...

thank god for slicks!

[blown 944]

pressure is a small part of the equation. Having more boost does not always mean more power (most likely less).
I make a **** ton more power now with 19psi on this engine than I ever did at 35psi on the old one. To take advantage of more air coming in you need to address quite a few things first, otherwise it is just pressure for the sake of pressure.

This has all been documented through my 1/4 mile trap speeds over the years.

[333pg333]

I've hit 2 bar a few times by accident. Usually running E85. I like 2 bar, is very fast!!

[968 GUY]

How much stress can the rods and pistons take? I'm guessing more than the head gasket.

[PAUERMAN]

I just did a dyno session today with the 951. I've run 1.5 bar with E85 for a number of years and thankfully the car has been absolutely reliable.

Here's a couple of videos showing comparison runs using different timing values and just a regular run.

951 Timing Comparison
951 Dyno Run

[ditch68]

Very impressive, Vic! I still tell people about my ride in your car. Fantastic. What a beast!

Vic has an engine management system that just completely impressed me.

Jeff