Attn: Engine buffs

[Cool Zr2]

I have a stock 350 vortec with 4 bolt mains. Out of a 97 3/4 ton.

 

I am told that the 3/4 ton 350 vortec's had more restrictive heads than the 1/2 ton version. Sooo, I just happen to have a set of new 305 vortec heads laying around. What advantage/disadvantage would putting those heads on my 350 have?

 

Thanks

[malibu795]

the 305 were designed fro a 3.735 bore make vlv is 1.94 intake and the exhaust 1.5. the 350 heads are designed for 4" bore and are common imporments are cut to 2.02 and 1.60 and ported. the 305 head run only a 58cc combustion chamber while the 350/400 head have 64, 76cc chambers. most common on truck are the 76cc heads. u can also use pre 87 head on that block ie 86 and earlier. in 87 the change the suface were the intake and heads meat as wellas the angle the bolts go in the heads. they make vortec manifold that will run carbs if u want to rid ur pcm. ur compresion will be raised from 8.75 to around 9.5-10.5. mainly 92 octane good low end torque lousey top end above 3500rpm. the heads cant surpport the air flow need. rocker arms are interchangable make sure the vlv cover bolts are in the location. if your looking for more power you can pick up a vortec head assembled for 520 a pair from summitracing gmpp parts ccast iron heads. edelbrock amke emision legal head bout 1100 a pair aluminum all assembled.world product also make the head for 87 up engined offers s/r torquer at 400 a peice 50 state legal

 

hope this help

wildman