flat spotting engine????

[mc_hawkings]

I've fitted a 1.4 nv engine & i'm getting flat spotimg after 3.5k. I've fitted the 1.2 exhaust manifold as i only have a 1.2 system. But the car that had the engine previously was the same ,ie flat spotting.

Things i've done to the engine are nothing. I will however fit a new 1.2 head & 1.3 inlet & new gasket & so on.

But what could be the causes of the flat spotting. Oh yes i have redexed the carb while driving along but still the same.

[Toby]

First thing to do is check for air leaks in the intake system, Id be a millionare if i got a penny for everytime i found a perished rubber around the master cylinder vacumn take off for example..

Best way to check is to buy a can of water spray and by spraying each gasket in turn and seeing if the engine note changes.

Of course this might be way off, but you could do worse than going to a rolling road and having everything set up right. ?60 per hour is the best way to spend the money, just make sure everything is in perfect working order first!.

[mc_hawkings]

Yup i tried spraying WD40 around the carb pipes & not a sausage no rev creeps atall. I did look at timing the belt is way loose, so ill just whip the head off next week then check the timing properly tdc an all that.

[rgv_stu]

second choke sticking will cause a flatspot