Thread: Timing Cover upgrade from V-belt to Serpentine

Originally Posted by LRCounty

I have an early 3.9 V8. While rebuilding the motor, I am upgrading the timing cover to the very first of the Serpentine covers.

Andre

G`day Andre ,

are you going to use all the serpentine bits ?

Are you using the later 10 bolt heads ?

Are you aware that the key/keyway for the balancer and oil pump drive is longer on a serpentine crankshaft ?

The water pump that fits the cover has an impeller that in normal use , rotates the opposite direction to a V belt water pump .

If your not aware of all the differences there`s no point drilling oil ways , so though i should ask first .

Thanks

Peter

Hi Peter,

Yep. Everything else is sorted. I'm using all serpentine ancillaries, and the serp belt etc. Mounting holes for the oil pump bracket, and the aircon/alternator bracket all accounted for. The crank is sorted too.
Just the question mark over the oil gallery diameter now.
I was about to put the crank in and start the rest of the assembly when I noticed the gallery size difference with the donor block sitting right next to it.

Cheers
Andre

I'm actually doing the reverse, serp motor but putting the v belt cover on. I wasn't aware about the oil galleries being different. Will my oil pressure change?

G`day Andre ,

I`d suggest if you think it easy enough , do it , mostly because bigger is more volume and the only reason i can come up with as to why the difference , the other galleries seem to be the same diameter but if you feel it`s not worth the trouble , i don`t think it would make alot of difference .

The crank driven pumps produce around 10-15 psi more but the old type can be adjusted to run to the same or greater psi , i`ve only read of this never used it .

Sorry i can`t be more helpful .

Peter .