High temp 454

[pttsls5]

Quite a while back I posted a question about my 72 454 with A/C overheating sitting at stop lights or stuck in traffic especially if it was a warm day. I ran into a 68-72 NCRS judge here in my home town and talked about my situation. He wanted me to put my original distributor back in and remove my Mallory dual point race distributor. He has the old dist. machine to spin it and dial it in. Reluctantly, we swapped them and then took it for a ride.Holy crap did he dial this old distributor in. He did put in new gears and shaft as well as trying 3 sets of different springs for max. performance. This car performs even better with the stock distrbutor and low and behold.....no more heating issues. Can idle hours in hot weather with no problem. Guess the problem of overheating was the Mallory race distributor uses mechanical advance that at idle is not advancing spark enough and then causing the engine to keep heating up until you accelerate increasing rpm therefore cooling down the engine with wind through the rad helping too. Just thought everyone would like to hear the outcome of years of frustration of my 454 overheating.

 

[froggy47]

Quite a while back I posted a question about my 72 454 with A/C overheating sitting at stop lights or stuck in traffic especially if it was a warm day. I ran into a 68-72 NCRS judge here in my home town and talked about my situation. He wanted me to put my original distributor back in and remove my Mallory dual point race distributor. He has the old dist. machine to spin it and dial it in. Reluctantly, we swapped them and then took it for a ride.Holy crap did he dial this old distributor in. He did put in new gears and shaft as well as trying 3 sets of different springs for max. performance. This car performs even better with the stock distrbutor and low and behold.....no more heating issues. Can idle hours in hot weather with no problem. Guess the problem of overheating was the Mallory race distributor uses mechanical advance that at idle is not advancing spark enough and then causing the engine to keep heating up until you accelerate increasing rpm therefore cooling down the engine with wind through the rad helping too. Just thought everyone would like to hear the outcome of years of frustration of my 454 overheating.

Good post!

 

[Vettehead Mikey]

Good post!

+1.

Probably 75% of the super zoomy blasto aftermarket ignition systems out there are a step backwards from the OEM stuff.

 

[Hib Halverson]

+1.

Probably 75% of the super zoomy blasto aftermarket ignition systems out there are a step backwards from the OEM stuff.

That's total unsubstantiated BS.

The problem with that car was not the existance of aftermarket parts. It was that the distributor which was installed was a race engine part not intended for street use.

It doesn't matter what kind of distributor is in the engine, Mallory, MSD, or stock, if the spark curve is not right for the application–as that one was clearly not–the engine is not going to run right and, in this case, "not running right" meant the spark was way retarded at idle and low engine speeds. Most likely due to the combination of the advance curve never having been set-up correctly and the lack of a vacuum advance.

Nothing like retarded spark on a street driven big-block to get the coolant temperature way up there.

 

[Vettehead Mikey]

If the spark curve is not right for the application–as that one was clearly not–the engine is not going to run right and, in this case, "not running right" meant the spark was way retarded at idle and low engine speeds. Most likely due to the combination of the advance curve never having been set-up correctly and the lack of a vacuum advance.

Exactly like 75% of the super zoomy blasto aftermarket ignition systems out there. Never seen one yet that was set correctly for the application right out of the box and/or had no vacuum advance.

otfl