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Spray-Bomb · 10-26-2008, 10:16 PM

The website you found has about all the info you will find for them on the internet

Dont twist it over 3400 (I liked to shift mine at 2800)

They have dual thermostats & are supposed to maintain no more than 4 degrees difference between cylinders & they last forever, just dont buzz it at high RPM for long & you'll be ok

They like big exhaust like a diesel, I had 2-1/4" on mine & I think it was fine for a stock carb, but if you were to put a bigger carb on it & take it apart & have it balanced & find a way to put a harmonic balancer on it so you could twist it higher, I think 3" would be better

Over Drive trans & some different gears in the rear to keep the RPM low would be a great addition... A NV-4500 would be what i would put
behind it

And my truck got rather decent mileage, Unlike what Andy said... But I drove mine slow & it was a 1/2T 3-speed

10-26-2008, 10:16 PM	#6
Spray-Bomb Texas Big Wig Join Date: Jan 2007 Location: Mineola, Texas Posts: 5,620	Re: GMC 305 V-6 Big Block???? The website you found has about all the info you will find for them on the internet Dont twist it over 3400 (I liked to shift mine at 2800) They have dual thermostats & are supposed to maintain no more than 4 degrees difference between cylinders & they last forever, just dont buzz it at high RPM for long & you'll be ok They like big exhaust like a diesel, I had 2-1/4" on mine & I think it was fine for a stock carb, but if you were to put a bigger carb on it & take it apart & have it balanced & find a way to put a harmonic balancer on it so you could twist it higher, I think 3" would be better Over Drive trans & some different gears in the rear to keep the RPM low would be a great addition... A NV-4500 would be what i would put behind it And my truck got rather decent mileage, Unlike what Andy said... But I drove mine slow & it was a 1/2T 3-speed __________________ Just not low enough... ----------------------------- Sinister Killer Last edited by Spray-Bomb; 10-26-2008 at 10:19 PM.