I've got a 92 rs 305 with blown head gaskets. Gonna get the heads worked at a machine shop and was wondering if there's any help to let them breath better. I know porting and polishing of course. Would anybody recommend going with a 1.84 valve in the intake side and shaving 0.020 off the face to help compression?

 

Take them to the nearest scrap iron place, sell them and find some 081 TPI 305 heads or L30 Vortec 305 heads. Don't waste a dollar on them. They are simply not worth it.

 

1-- trick flow 175 heads

2--- 305 vortec heads

3--- TPI 305 heads

9,876--- rebuild the stock TBI heads

 

How will I know if they are L30 Vortec 305 heads or 081 TPI heads, what do I have to look for-casting numbers, if so what are they? What's better about those?

 

Can I use the same rocker arms that are on my current ones?

 

Are there certain vehicles that apply i.e. Tahoe, c/k 1500?

 

Will a 520 or 059 casting number work?

 

The only ones I've found are for 1996-2002

 

Finally, do I have to change my intake manifold or can I reuse the stock one since it's a TBI car?

 

On the Vortecs you can use a Vortec Carb manifold and get an adapter to use your TBI. Lots of people go that route being the Vortec TBI manifold is a bit pricey.The 081s will take your stock manifold.

 

Tomorrow, I'm picking up a set of Vortec heads and intake manifold from a 96 c-1500. Will my current tbi work with that manifold or do I need an adapter plate for that also. If so, does anyone know the part number?