Slant runs like crap when first accelerating..

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Rockerdude

Rockerdude

Rock n' Roll and A-bodies
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My 225 slant six has an issue with taking off from a stop. The motor when you first start to press the gas starts to buzz and barely starts going, after that is smooth.. I checked the timing and at idle it is reading 0, and when pushing the gas it retards when it buzzes then advances when its fine. The vacuum advance is also hooked up. Also the car runs REALLY hot. Like closer to the H then the middle, I had the radiator gone through yesterday and it didn't really make much difference.

Thanks. RD
 
pull the distributor and take a look to see if the bushing, plastic gear or advance plate/weights have issues....then look at the ignition box if electronic.

After that, grab the crank dampener and turn it back and forth , feel for when the timing chain slack tightens up and grabs the timing gear, how much back and forth there is can tell it's time for a chain and gears.

The other thing that can happen is the flapper in the exhaust manifold likes to rust/crust up and stick closed, make sure it moves.......and after that ...lol ....look at the carb

Thats How I would do it.
 
When convenient, you might want to have an O2 sensor bung welded in the exhaust pipe. That will allow you to monitor A/F ratio. Otherwise, hard to know what your carburetor is doing.

Holley has an indicator box for $120 ($170 w/ sensor), but shop around. I got a similar system off ebay for $10 w/ sensor (surplus from propane system). Later found the Holley box for $12. I also got several wideband O2 sensors for ~$20 for a later upgrade.
 
Could be slipped marks on the dampher. Late timing can cause the overheating. Try advancing it a bit and see if it runs better.
 
I pulled the dist out and found the bolt holding the key way in place was all the way retarded, so I put it in the middle and so with the key bolt on the block side and it responds much much better, but it now has a knock... NOOOO!
 
It kinda sounds like a diesel knock.. It only happens here and there though, not every revolution.
 
Sounds more like detonation due to too much timing. I would check the entire tune on it. The timing is only one aspect. The points also effect the timing as well. Make sure everything is as it should be. Everything.
 
Think it could be too much carbon built up on the pistons? The compression test came in around 160psi on most cylinders..
 
You shouldn't have randomly moved the distributor hold-down plate relative to the distributor body. That adjustment is only for if you can't get enough movement in one direction or the other to attain the correct base timing, which is not the 0° you first read (and is also not whatever monster amount of timing advance you randomly cranked in by moving the dist plate). Verify that the timing mark on your crank pulley actually indicates TDC, then set the engine idle speed correctly, disconnect the vacuum advance and plug the carburetor port, then set your timing at 5° BTDC.

Tune-up parts and technique suggestions in this thread. Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download. The engine might also be overdue for a valve adjustment.
 
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