70 LT1 heads, any good?
07-22-2007, 01:12 AM
#1
70 LT1 heads, any good? I am looking into a set that are ported and polished, 2.08 1.60 valves, studded with guide plates and have trip. springs good to .650 lift, 300$ is the asking price and i know the springs and valves are worth that, anyone think these would be a ok head to run a 236 242 @.050 .520 .540 cam? I think it is a good deal and i just need some decent heads, he claims to flow 285 or so thru them, any input???
07-22-2007, 02:15 PM
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They could very well flow 285cfm. I would think at least 270ish. Thats 500+Hp with that cam. I believe you would have an EASY 420rwhp with that cam in 350ci. I would say JUMP on 'em. You could have a 10second car for next to nothing.
07-22-2007, 07:53 PM
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First I would get a GM casting number off of them and make sure that they are era correct. You can make a set of 882 smoger heads run well with that cam depending on your intended use. Make sure that the cam needs a triple spring, which I really doubt that they do. Unless you are talking about a double spring with a harmonic dampner. If this is the case get the spring specs from him and call your cam company to make sure that they will work with your cam.
07-23-2007, 01:08 AM
#5
Yea, i looked up those numbers, there were the 70 LT1 with straight plug and there was an over the counter 292 but the first numbers were different, i hope to make 450 with a stock 90 chevy short block just to play with till the 408 is ready, the 97-95 sbc 350 mabe 9 to 1 with 76 cc heads right? These being a 64cc head would be bout 10 to 1 right?
07-23-2007, 01:34 AM
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Yes if the motor was at zero deck, but that is usually not the case. The top of the piston is usually sitting 0.025"+ below the deck. Your stock short block with those heads, depending on the head gasket used, will be closer to 9.4:1.
07-23-2007, 11:50 PM
#7
i can live with 9.4 or so, if it was 8.9 or less the cam would be pointless, thanks gentlemen. I hope to get the LT1 in my 95 back together then i can buy those heads and get the 89 back up, i will post some dyno sheets if you guys want when the time comes.
