Thanks to everyone for their insight. I have a set of 58cc world product 305 heads 1.94/1.50 with screw in studs. What are your thoughts on using them with my dome forged pistons?
Those are probably the best heads you'll find for the 283. If your compression was 9.7:1 and you're going down to a 58cc chamber, I'd make sure you're not going to interference and an unreasonably high CR. If you're good with running higher octane fuel, it sounds like it will be a hard runner. Compression is the hallmark of a high performance build
Id calculate the compression carefully with domed pistons and the small chamber. how big a dome are they ? how far are they down in the hole ? what gasket ? All that. If it all clears it should be a good set up if it runs on the gas you have .
From what I've read those heads flow pretty well. Might consider swapping to a 1.60" valve, and of course have screw in studs added to the rockers. But even with 1.50" valves in a 283 they should work. I too am a little concerned with the dome on your pistons, but once the compression is calculated, if it's too much you can always have the chambers unshrouded easily and cc'd to match and lower it if it's too high. With today's gas quality, and low octane ratings my 350 SBC with 2.02"/1.60" camel hump heads, flat top pistons, and 59cc chambers wont run on 93 octane without me adding some VP Racing fuel to each tank to boost octane. Not a big deal, but it does add to the expense, and h***le a little to enjoy it.
Thank you very much for sharing your knowledge. I will get the crank back soon from the machine shop, check my deck height and approach this process with a lot of thought.
The press in studs are fine unless you start running big numbers on valve spring pressure. I had a SB Ford that they had drilled the head and studs for roll pins. That worked fine and didn't require any extra machining.
So now...........you're going with 58 cc heads and dome pistons !?! You 'may' have gone all the way to the 'other' end of the spectrum ! With iron heads and hi test fuel I wouldn't wander too far above 9.5 -10:1 CR. I would skip the thin steel shim head gaskets! The L-79 cam has a pretty tight LSA which will HELP you with running big compression on a street rod. Light weight car is a + too! I would use a 160 degree thermostat in it too. (Cooler = less chance of spark knock/detonation.) Manual ****** is a + to keep from lugging engine. TUNE-that ignition !!!!! BIG LSA need a LOT of initial advance in the timing department. A good place to start is a total advance of 36-42* all in by 2000 RPM. (ya gonna need light springs in that distrib.!) A little un-shrouding around the intake valve and POLISHING of the chambers will lower the CR some too. With good springs that lil Shivel-lay could get into the 'Opera' zone nicely. (6000+) With resized big-ends on the rods and ARP rod bolts that RPM level should be fine..... 6sally6
Thank you for the advice! I will get the crank back soon, build the bottom end and see where my deck height is at. I need to rationalize my driving style and my vision for the coupe. Thanks again, Paul
Roll pins serve the same function until you break a stud. Then they're a PITA to get out and replace the stud. The cost of having heads D&T for screw in studs is minor, and so much easier for owners to service or repair/install studs themselves. The last pair of SBC heads I had done cost me $550 to have all new hardened seats, SS valves, high lift springs, and D&T for studs, plus the valve job. I think the D&T for studs was about $50 of that price?
Thanks, the machine shop quoted about 550 to D&T, resurface, valve job and hardened seats...didn't include valves or springs.
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