4.2 power/cam type

[Greegor]

Can anyone tell me if 309bhp @ flywheel on a late 97 is due to it having the 'quiet cams' or is it more likely to be that the engine is just not kicking out as much power as it should be? Also does anybody know when the factory started producing 4.2's with the 'quiet cams'? I am currently trying to find the best all round Cerb I can buy, looks like it will have to be a 4.2 due to funds, any advice will be much appreciated

[dannylt]

Was this on a car you were thinking of buying? I would ignore the whole quiet cam/noisy cam issue, since it's not as simple as all that - really early cars had poor backbox designs and inefficient manifolds - small ports I think. Besides, the quieter cams were mainly quieter because of the "onramp" to take up the clearance nicely - this is purely a design issue and would just increase longevity and reduce noise. I think they did have slightly less peak left, but they also had longer duration. I would go for a quiet one, since it's obviously had more attention - it is an "upgrade" after all.

However, 309 is definitely not ok for a 4.2. Reasonable figures are 330ish. A few have more, and why accept less if you know it's less? Apparently 25bhp is feelable on the "seat of the pants" dyno, according to John Ravenscroft. It could have running problems; worn cams/tappets/tune/plugs etc. Though some cars just have less power without any obvious reason.

Joolz is the man to talk to! I'm sure he's lurking around here somewhere...

danny


>> Edited by dannylt on Friday 7th February 22:41

[Greegor]

Cheers Danny, the car is one I looked at on Friday it was great apart from the low power reading. Apparently Joolz has worked on the car, hopefully he may be able to help with a little info.

[joospeed]

309 is pitiful for a 4.2 - hope it's not cos I worked on it
let me have some info on the car and i can tell you what I did to it, but if that figure is off a reputable dyno then it's probably one to be avoided anyway unless the rest of the car is stunning.
Joolz

[batman_robin]

that's was me Joolz, i think all the cars at that day in Chelteham was down on BHP...include Danny's RR...BTW my figure was 329, not 309.

Danny