Dead Spot

[XiT]

ok so with my f8b na when i put the foot down in any gear the car will die down a bit then pick up ... i assume its a timing issue but not to sure as we have played with the timing a lot. Could it be spark plugs as autobarn didnt have the exact plugs so we went to the next model of plug.
cheers.

[Tez]

When you say "you've played with the timing a lot", do you know where your timing currently is, and why you have it there? (I'm hoping there's a confident answer...?)
I would set the timing back to factory default (+7 degrees @ below 900 rpm) and see what that does for your flat spot. (Assuming your engine is standard).
Timing/performance can also be affected badly by poor/absent/faulty vacuum advance, so that's something I'd look at next, after confirming where the timing is...

[KEVIN]

Could also be an accelerator pump issue but why have you been playing around with timing is it for the same problem?

[killermule]

Mine does the same thing on and off.... kind of figured it was about 10 different things at fault and hoping it will just go away as i replace stuff with new stuff haha

[XiT]

the timing plate is missing but the idle is around 900 and yea motor is all standard

[Tez]

Geez. If the timing pointer inside the bellhousing is missing, that's gonna make getting your timing right, almost impossible. The graduations are marked on the flywheel, but you need the pointer there for reference.
The very best you will be able to do is make VERY small adjustments of the distributor (assuming you've gapped the points correctly!) and test drive it to see if there is any improvement or worsening of the situation.
Maybe scratch a line across the distributor bracket and engine block where the quadrant adjustment screw clamps the distributor in place, and then move it a SMALL amount one way or the other... (maybe 1.0mm only) and test drive.

Of course you could always pull the motor/trans and split them to fit the pointer...!

[XiT]

well using a timing light it shows that is fairly good. I'm not a big mechanic im just learning, my old man is teaching me as we go trying to work it all out

I'm getting all the ideas I can so we can pull it apart and really get into it next week

So keen to get it running smooth

[Bear351c]

Could also be an accelerator pump issue but why have you been playing around with timing is it for the same problem?

I'm with you, accel pump on carby.

[cozza]

i had the same problem for a while but once i replaced the points, condensor and the leads and plaugs as well as dizzy cap and rebuilt the carby that problem went away untill the fuel pump started to leak and it came back so i replaced the fuel pump and it goes like a new car again.

[XiT]

Cheers guys gives me some work to do.
Much appreciated

[Colin]

if it was your timing (retarded) it would either feel flat all the way throught your rev range
if it was over advanced it would pink (ping) when under load
the flat spot your talking about is carburettor related and id put my money on a accelerator pump not working

[XiT]

Thanks for pointing it down to the carb
what do you mean by (ping) under load ??

[Bear351c]

Yep. 'Pinging' is the air/fuel mixture in the cylinder, exploding before the spark has fired. Also called, 'knocking' 'dieselling' 'detonation'. If this is your prob, try driving up a hill, foot flat to the floor, you'll hear the noise. Usually a timing issue. Or compression too high, for fuel octane used.

[Tez]

Yeah, but if your car IS pinging, don't drive it like that for too long - it will kill your engine.

[Colin]

pinking(pinging)is the audiable sound given off when the timing is too far advanced and the air fuel mixture detonates instead of burning while the mixture is being compressed on the compression stroke ,this detonation is trying to push the piston back down the cylinder but is unable as the flywheel keeps the forward momentum going .it can cause poor preformance ,blown head gaskets,premature wear on the big end bearings and damaged pistion/rings.