Building a 283 for my 51 Chevy Truck and need some advise. Bored .60 over, turbo 350 with a 2000 stall, 3:73 gears. I have a set of Power pack heads that are going to cost in the area of $325 to rebuild. I can pick up a set of 350 heads for around $250. OEM, Cast Cylinder Head, GM 350, 1978-80, Casting # 462624 Is this too big of a head for this build? Should I just stick with the Power Pack heads?
the open chamber 350 heads will lower the compression a lot. you can use mid 80s 305 small valve heads that have about 68cc chambers and they will work with unleaded gas. OldWolf
I've never used them on a 283 but I am told 305 Chevy heads are a good choice. Power pack heads are small chamber. I think the 350 heads you are talking about are large chamber and if you use them the compression will go South. You may also have valve to cylinder wall clearance problems. Does the $350 Power Pack head rebuild include hardened seats? With today's unleaded gas that can be a problem. Power Pack heads do not have accessory holes. Depending on what bracketry you plan to use this can be a problem.
Yeah they are going to put in hardened seats and I figured I would only be running an alt so accessories I'm not so concerned about the holes. I guess I'm just going to bite the bullet and have them rebuilt. The cheapo in me wanted to save a few bucks.
Rebuild the Power Pack heads, $325 is not out of line for a decent rebuild and is actually on the cheap side. As already stated the 350 heads will dump your compression, probably somewhere in the lethargic 7:1-range. Keep your 283 all 283.
i'm just putting togather a 283, i have a good set of powerpac heads for it, my next 283 i was thinking of using vortec heads or the set of 194 camel humps i have.
I would go with the power packs. I put $300 in mine and put them on a 327. Love em. You can take the intake valves up to 1.82, slot out the push rod holes, put on screw in studs and guide plates plus new springs retainers etc. Then run a split set of roller tip rockers, 1.5 on the intake and 1.6 on the exhaust. On my 327 I get nice crisp response, more than enough power for me, and with a 500 cfm Edelbrock I get roughly 21 mpg on the highway.
Use the 305 heads! You'll get the hardened seats right off the bat, and accessory holes to mount a/c,p/s,alt, etc. #416 305 heads have a 58cc chamber 1.84/1.5 valves; #601 305 heads 1.72/1.5 valves, same as your 283 heads, and have a 53cc chamber that will bump the compression a bit. Use the powerpack heads for bartering, unless they are original hi-po heads. Then sell them to a restorer. Use the 305 heads!
Ive done a fair bit of research on this swap too. I grabbed a set of # 601 heads on Ebay that were mildly milled to true em up, c/w Z28 springs, K lined guides,fresh seals, SS valves, screw in studs and new guideplates, CM retainers and hardened seat inserts, all fresh and ready to go for 275 clam$. There will give better CR, look original, flow better and are brand new. IMO how can you go wrong man? 305 heads were the best option $$$ wise. Rat
Hard as hell to find, but 265 Power Pak heads make a 283 run like a scalded cat. Same combustion chambers as the 283 FI heads. Had some of these heads on a 292 and ran 13.08 in a 61 Vette.
While I have a little time I'll keep my eyes out for a set of 305's and if by the time I'm ready I havent found a set I'll probably just rebuild the set I have now. I'm also going to do a little more research on them and see exactly what I have, just in case they are something special.
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