Wont rev much past 3500

[damnfinechim]

Hey guys,

Finally had her out for a decent run today. Man.. the motorway is soooo much fun. hehe A bit noisy up around XXX miles though (roof on, windows up) cant hear that beautiful engine. :(

On the way back it seemed that i couldnt rev much up past 3000 (3500 topped out). Any suggestions? I cant think of anything that I did or changed (wasnt really caning her).

Now she's back at home she's idling high (around 2k).

Just happy to have been out for a decent drive finally.

BTW - SPOTTED green griff on the A110 in Enfield, cheers for the wave. :)

Kempy

[parrot of doom]

Check the throttle cable is aligned properly?

ie turn engine off, depress pedal, get mate to check if its pulling the lever all the way across.

[Boosted LS1]

Have you tried caning her, maybe you aren't pressing the pedal hard enough? Keep us posted.

Boosted.

[damnfinechim]

Boosted LS1 said:

Have you tried caning her, maybe you aren't pressing the pedal hard enough? Keep us posted. Boosted.

Yeah, thats what i originally thought but it is really struggling at around 3500 - 4000. Wasnt like this before though, was happy to kick on to about 6000.

POD - Will check the throttle cable today and see whats what.

Thanks,

Kempy

[Boosted LS1]

Make sure it's not pinking! Sounds like it's holding back and has an air leak somewhere. I'd check all the hoses around the plenum and drive it easy until you find the fault. Also check the plugs and leads incase it's not firing on all 8 cylinders.

Boosted.

[damnfinechim]

Boosted LS1 said:

Make sure it's not pinking! Sounds like it's holding back and has an air leak somewhere. Boosted.

Now that you mention it... up around 90 it seemed to be missing a bit. Could this be a air leak too? More likely to be points and plugs yeah??

Thanks for the pointers.

[GreenV8S]

Sometimes the air intake pipe between the filter and the plenum can delaminate and collapse internally under the slight suction you get at full throttle. This causes symptoms just like yours. If it isn't that I would suspect either the air flow meter playing up so the engine is leaning out at full throttle, or an ignition fault causing a misfire. A misfire severe enough to lose this much power would cause very obvious rough running; the other problems would reduce the power but leave the engine running smoothly.

[damnfinechim]

It seems to be running absolutely fine otherwise.
Will have the bible out next weekend to see whats up. How will i know if the inside of the pipe is corroded?

Cheers,

Kempy

[GreenV8S]

Delaminated, not corroded. Take the pipe off and look down the inside. If the inner lining is sagging, it's delaminated. If it is still firmly attached to the spiral wire along the whole length then that isn't the problem.