View Single Post
David David is online now
David's Avatar
Join Date: Apr 2002
Location: Houston (Clearlake), TX
Posts: 9,587
Sounds like too little power to me.

Fuel pressure should be at least 6 bar or 87 psi, so it's a bit low. I'd check fuel flow too, which should be 1.5 liters in 30 seconds.

CIS is opposite to EFI when it comes to the control pressure and fuel delivery since the higher the control pressure, the less the fuel head piston can move so it flows less fuel. Where a higher pressure with EFI gives more fuel flow. What's your hot control pressure?

Have you double checked your cam and ignition timing? Of course the ignition timing should be set on the dyno so it should be right.

Was anything changed on the intake or exhaust that could be limiting flow?

I have the 100mm JE pistons and I measured a compression ratio of 7.7:1 so your compression may be a little less. I wouldn't crank up the boost until you sort out the problem, but I think 1 bar for the street and .8 or .9 for the track should be safe with enough fuel.
2014 Cayman S
2011 Cayenne Turbo
1979 930 (475 rwhp at 0.95 bar)
Old 03-28-2008, 10:03 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #27 (permalink)