rich mixture

[craigh]

since installing my new heads and cam on the 302 it now shows all the signs of being too rich,sooty plugs and exhaust,and some bogging down on harder acceleration,its also a bitch to start when cold
its currently on a 500 cfm carb which i have been advised to keep to get better throttle response,the carb performed fine on the stock engine and ran straight out of the box with near perfect plug colours
i have also had to hook up the full vacuum port on the carb to allow some advance at idle due to an annoying starting problem,it now only runs happlily on 15 to 20 degrees initial,anything lower and it struggles to start ,it will just turn over stop,turn over stop as if the timing is way out
heads are trick flow track heat 2.02 intake/1.60 exhaust and a comp cams 268h
any thoughts please

[neil still building it]

hi

i'd double check you've timed the cam correctly as it sounds a bit suspiciously connected ,this can affect so many things and prove difficult to trace .this will obviously affect ALL timing also .and make starting difficult -starting to sound familiar??
get checking
NEIL

[craigh]

i used the straight up position on the timing set,didnt want to get too technichal on the advance and retard keyways,maybe it needs to be degreed properly

[craigh]

i took off the timing cover today to double check and everything looks ok,timing marks line up, both in correct position,so now im stumped

[TINKA]

Have you checked for any signs of an air leak ?

[craigh]

i have checked and cant really see any,beginning to wonder though if my inlet manifold gaskets are sealing properly causing problems,i do have a slight oil leak at the rear seal

[TINKA]

Just sounds a bit like a problem I had on my Rover setup which in the end was down to one of the breathers leaking ( I think ) HTH

[neil still building it]

hi
if you feel there's a leak try using WD40 or soapy water on the suspect area,when running ,there'll be a dip or increase in tickover .
or try using a vacuum gauge...?
good luck
NEIL

[mikey]

What is your cam profile and duration / overlap etc. There is nothing unusual with running initial timing at 18 to 20 degrees- it may need it. However you need to make sure your total advance dosent exceed 34 to 36 deg. You do this with a bushing in the distributor advance mechanism. The black bush normally gives around 18 degrees.

If you havent got a dizzy that allows you to do this, think about one.

Bog under acceleration can easily be caused by ignition timing as well as carb. Check your accelerator pump arm for instant shot and pump cam for duration.

I have a feeling that it may be more your timing from your comments about starting. A quick test would be to take your initial timing up to say 18degrees or even 20. Take it down the road and give it a quick blast. If it seems to have significantly cured the problem you need to limit your overall advance as I mentioned above.

If you want to chat it through e mail me and I will try and help
Mike

[snakebite]

Originally Posted by craigh

i have checked and cant really see any,beginning to wonder though if my inlet manifold gaskets are sealing properly causing problems,i do have a slight oil leak at the rear seal

If you had a mainfold leak wouldn't it be running weak and not rich.

Have you altered the secondary throttle plate settings?