81 looses power
mitademedio
05-13-2007, 12:16 AM
I have a 1981 el camino with a 350 engine and a four barrel carb,whenever i step in the gas the car looses power for a few seconds and the takes off,any pointers of what migth be?
this happens only if give it too much gas,if i go gradually the car works just fine.
this happens only if give it too much gas,if i go gradually the car works just fine.
silicon212
05-13-2007, 12:25 AM
You said it has a 350. Since the original '81s were only available with a 305 as the larger V8, I will assume this is not the original engine - but then you know what they say about assuming.
If this is a swap engine and you're using the original 305 carb, then you will likely need to readjust the tension on the air valve spring. The 305 doesn't create as much vacuum as a 350 does, so the air valve is tensioned a little higher. With the added vacuum on the 350, the valve will open earlier than it should and this will cause the engine to "bog" before it comes back due to the overlean condition. This happens because the valve lets in too much air before the gasoline has time to enter the secondaries. My uneducated guess is this is the problem.
If this is a swap engine and you're using the original 305 carb, then you will likely need to readjust the tension on the air valve spring. The 305 doesn't create as much vacuum as a 350 does, so the air valve is tensioned a little higher. With the added vacuum on the 350, the valve will open earlier than it should and this will cause the engine to "bog" before it comes back due to the overlean condition. This happens because the valve lets in too much air before the gasoline has time to enter the secondaries. My uneducated guess is this is the problem.
mitademedio
05-13-2007, 12:36 AM
You said it has a 350. Since the original '81s were only available with a 305 as the larger V8, I will assume this is not the original engine - but then you know what they say about assuming.
If this is a swap engine and you're using the original 305 carb, then you will likely need to readjust the tension on the air valve spring. The 305 doesn't create as much vacuum as a 350 does, so the air valve is tensioned a little higher. With the added vacuum on the 350, the valve will open earlier than it should and this will cause the engine to "bog" before it comes back due to the overlean condition. This happens because the valve lets in too much air before the gasoline has time to enter the secondaries. My uneducated guess is this is the problem.
Thanks for the quick reply silicon,it had a 305 but when it kicket the bucket i dropped a 350 that i had laying in the garage,it was a complete swap carb and everything...minus the balancer,the car run well for a while,i assuming is either the carb or the timing needs to be adjusted.
If this is a swap engine and you're using the original 305 carb, then you will likely need to readjust the tension on the air valve spring. The 305 doesn't create as much vacuum as a 350 does, so the air valve is tensioned a little higher. With the added vacuum on the 350, the valve will open earlier than it should and this will cause the engine to "bog" before it comes back due to the overlean condition. This happens because the valve lets in too much air before the gasoline has time to enter the secondaries. My uneducated guess is this is the problem.
Thanks for the quick reply silicon,it had a 305 but when it kicket the bucket i dropped a 350 that i had laying in the garage,it was a complete swap carb and everything...minus the balancer,the car run well for a while,i assuming is either the carb or the timing needs to be adjusted.
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