I have completely rebuilt my 454 engine, including a mallory breakerless distributor, no vacuum advance. I have a ballast resistor in line with distributor. Engines idles smooth at cool temp. When driving, I can not rev up past 2900 RPMs in first. Once engine is warmed up and I attempt to rev engine, it begins running rough & tries to stall, and diesels when I shut it off. On going problem for 2 years. Using a Carter 4-bl carb.
I have new plugs , wires. Any ideas?
I have a Mallory 9000 electronic module Distributor (breakerless) on my
1970 BB and it doesnt have a ballast resistor ; better check with Mallory to see if its even needed. I suspect it isnt.
What I would do:
1) I would pull off the heads and see if there was any weird carbon built up on the pistons that get red hot and cause early fuel detonation and dieseling on shut-off. 2) I would look at how my fuel is going to the carb - if it gets really hot then it turns to a vapor (which it should not do) and that's not how it's designed to work. 3) I would rebuild the carb (easy to do and quite inexpensive to get a felpro rebuild kit) 4) I would take it to a mechanic if the first 2 observations came up empty.
Sounds like an ignition problem to me, too, but there are other possibilities. Shouldn't be too tough to stick a Chevy HEI distributor in it for a test to find out if it's the distributor. Likewise for a carburetor... doesn't have to be the exact correct replacement carb just to run tests.
Only happens in FIRST gear??? What about in other gears? Neutral?
Does the engine rev up OK when it's still cold? Are you running the right heat range spark plugs? What do the plugs look like when you pull them? Hi-test gas? Does engine run at normal temp once it's warmed up? Decent spark plug wires, correctly routed and separated? Double-checked all the spark plug wires are connected to the right cylinders? Double-checked valve/lifter adjustments? Carb secondaries open OK (ie, no linkage problems)? And is the Carter carb (it's not the original) adequate? Is it possible you have a stuck heat riser valve (or that you re-installed it upside down)?
If it were mine, I think after 2 years I'd take it to a tune up shop and let a pro have at it..
Check to see if distributor was installed 180 degrees out. It can be done and it will run.
. On going problem for 2 years.
you do know 454 are externally balanced ???
Golf:
Sounds like a compression check might be in order. Could be a head gasket, burned valves, or a valve not closing completely if it's a solid lifter cam.
I vote with Wayne. You can swap out the distributor and the carb in such a short time, it is the best way to find this in a hurry.
Dieseling is most likely timing. Use an adjustable timing light to see what your timing is at 3000 rpm while sitting in the garage. It should be somewhere around 32-34 degrees. You could have even 38, but other than those, you have a problem. No vacuum advance is a racer toy and not good for the street. You'd have much better performance with a good tuned HEI plus you can buy parts for it anywhere in the US of A, if you actually ever had to buy parts.
Carb. By Carter, I assume Carter Q-Jet or similar replacement, not the Carter AFB. Replace the bronze filter in the inlet? Are the secondaries opening? With it warm and the air cleaner off, open the throttle and see if the secondaries open. The choke could be adjusted wrong and holding the secondaries closed.
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