The V8 Owners Forum -

Hi,

I've got a P38 with a GEMS 4.6 engine in which feels like it is down on power and also has a slightly rough idle. I recently rebuilt the engine with a top hat liner block because my old one cracked. Even with the previous engine it never had much power so I don't think it's a mechanical problem. Everything in the engine is pretty much new such as rods, pistons, crank, cam, lifters etc. I can't remember what cam it was at the minute but I got it from v8developments and they said it would work 100% with my GEMS ecu without having to dial it in.

Other things I've already tried/replaced/tested:

• Tested compression, all cylinders were around 155psi.
• Tested fuel pressure - seems OK.
• New plugs, leads, coil pack.
• New o2 sensors
• New MAF
• Swapped TPS, IAC, engine management ECU with some ones I had lying about - no difference.

Has anyone got any ideas of anything else I can try out to try and figure this out?

Thanks [/list]

Have you read out any fault codes?

Are the brakes seized (including the handbrake)?

Have you tried a different one to see if that feels any faster? Try a 0-60 sprint.

Chris.

Forgot to mention there are no fault codes ever appear.

I don't think the brakes are seized. All were checked recently when I changed the pads and I the front calipers.

No I've never tried a different one. I'd like to though. I think it feels reasonably ok at full throttle it just feels like it's lacking power on hills and at part throttle.

It's getting dynoed on Friday so that should be interesting.

I was thinking about checking my cam timing. Is there any reason I can't do this when the engine is in the car? As far as I can see all I need to do is make something to stop the piston via the spark plug hole, take a rocker cover off to measure lift via the pushrod and stick the dial gauge on the front pulley. Is there anything I'm forgetting?

I believe you are right about measuring cam timing just by removing a rover cover.

Chris.