Rough Running

[joshuajones]

Can any one advise me how the car should run. Back from the garage being tuned etc. Should it run smooth or is it the nature of the engine to hunt a little. I don't expect it to be smooth at 30mph in 4th gear.
What does any one else expect from their engine?
Second problem, new clutch fitted and it judders in reverse at slow speed. Slight ramp up to the garage.

Advise anyone would be much appreciated.

[pac1uk]

I don't think that sounds right. I have not noticed any thing strange or odd with the clutch, behaves just like any other car.

I only get a bit of hunting when starting from cold, once the engine is warm it's fine. What's it doing driving at 30mph in 4th? I have done this, you can drive it quite lazy. I don't remember anything adverse.

My car is a 400 with standard bits.

[JFReturns]

Mine pootles okay at 30mph in fifth. Recently replaced leads, shrouds, cleaned stepper motor and got rid of an inch of rotten vacuum advance pipe which made a huge difference.

[Dr Mike Oxgreen]

'99 450 here, which has no hunting at any speed, so I wouldn't say it's normal - although it is very common. My engine is supposedly totally standard, although it produced a slightly suspicious 276 bhp at SRR a couple of years ago, which makes me wonder what cam it's got. It idles with a slight unevenness.

The clutch is heavier than other cars, but otherwise feels and behaves the same.

[Robert Lees]

My 450 hunts a bit, and has mark Adams chip, induction kit and trumpets. Don't think i could drive mine at 30 in 5th.

been serviced recently with ignition timing done, still has a " pause" at about 3000 rpm, new plugs, leads etc.

i think all run slightly different.

[Grey Ghost]

My '98 450 used to struggle a bit on start up. At the annual service this year Dom and his crew took the injectors off, cleaned them thoroughly, flow matched them and put them back in.

Bingo totally different car and so much smoother across the entire rev range

[blitzracing]

The idle can be a bit rough as the ECU tries to keep the emmisions down and cycles the mixture. This point is fractionly leaner than the RV8 likes, and combined with a higher performance cam that TVR fit means they are never that smooth, but the idle should not hunt as such- it should be around 800 rpm (Chip dependent- the Mark Adams chips idle a bit higher). If the RPM is constantly shifting up and down you may have something like an air leak, that the ECU is trying to adjust for and cant.