Steve Lavigne

I always thought that the Turbo S used the same fuel pressure regulator as the 944 Turbo. I just looked on Paragon's site and noticed that it has a different part number listed for the '88 Turbo S and '89-'91 951's.

I have heard that the Turbo S intake manifold is slightly different and it has an additional banjo fitting.

Can anyone shed any details on the difference. Specifically, I am wondering if the the pressure spec or the vaccum pressure/boost pressure curve is different. Any information at all on this would be much appreciated.

I have an '86 951 with a K26-8 and 24 pin chips mapped to this turbo. I currently have the standard 951 fpr but I seem to be having some problems. Perhaps this fuel pressure regulator is the problem. I was told previously that they used the same regulator, but obviously this is not completely the case.

951and944S

Steve, why don't you call and verify that it's not a misprint intended for the S model, as in the 16V S car.
I'm fairly certain those engines do run more fuel pressure than any turbo version.
If I'm not mistaken the fuel pump also provides more volume for the 16V S.
Don't know about the extra banjo bolt. or what it would possibly be used for.....?

Good luck

Robby

I'm not SUREE about this, but I DID ask a long while back about the fuel press of the Turbo S, and started asking about injector size, etc, and IF I remember correctly (that's a big IF too BTW): the S2 and 968 ran higher fuel pressures, but they also had smaller injectors. The Turbo s injectors are pretty damn big (they may actually be the exact same size as the turbo, but again, I'm not sure)... So, I guess I really didn't help you much- sorry...

Danno

Do a search in the 924/944/968 and the 944Turbo/S areas for "951 injector size" and you'll find that we have yet to come up with any conclusions for the 951 injectors. From the part#, it appears that the 951/951S/968Turbo all used the same Bosch injector. Flow-testing by RC Engineering also shows a wide variation between different sets of the same injectors. No idea what's going on.

Anyway, when I had first upgraded my car with the MAF-4 kit and turned up the boost to 15-psi, I found that turning up the fuel-pressure with the 3-bar FPR from the S2 helped with high-RPM/full-throttle running. Smoother with no pinging like before. After I installed the Stage-II turbo, I had maxed out my injectors at about 290rwhp.

BTW- Looks like Paragon raised the prices on the FPR, I got my S2 unit for something like $38...

Kool

I paid $43 for my 968 FPR.

StanUK951

So for someone with only relatively mild mods like me I guess it is cheaper to buy a 3 bar FPR from an S2 or 968 rather than an adjustable one..?

<img src="confused.gif" border="0">

toddk911

What is the difference between the 968 and S2 FPR?