Thread: 496 with 840 rectangle port heads

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Im building a 496 and cant really afford aluminum heads. I have a good set of 840 casting number rectangle port heads. They need a valve job, probly milled and i would like to put in hard seats and stainless valves. In the mean time i was given another set of rectangle port heads that have brand new stainless valves and have been ported and polished about 30 years ago. One heads was damaged and i do not want to use them. I pulled the vaklve to put in the first set of heads but found out the intake valves are 2.30 intake and stock 1.88 exhaust. I want to make as close to 600 hp and close to 600 ft lbs of torque so the question is should i have th larger intake valves put in the heads? Would there be a significant gain by going to the larger intake valves? Or just buy new 2.19 valves

I will be replacing the 396 that i have in my 72 nova

A. Street only.
B. Street and Strip.
C. Strip only.
Rear gears.
Converter stall.
Intake manifold.
CFM.
Static compression ratio.
Curb weight with you in the car and a half tank of gas.
Rear tire size.
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Welcome to the club. Nice looking car. Thanks for the pic.

I think TechInspector is asking some questions.... I haven't priced it out myself but I think there are some new aluminum heads that will be within your reach once you see what repair/ rebuilding / replacing valves and seats costs. Esp. when you're talking Chevy parts.

Street driven only
255/60/15 , 28.5 tall
3.73 gear
4 speed
Rpm air gap intake
950 quick fuel
Com cams .566 lift in/exh. 112 ls , 110 cl, 242 intake and 248 exhaust duration @.050 its is a marine grind roller cam
Roller rockers
10.5 static comp
Msd ignition
3500 lbs car

UThanks 30_40, Here is the before pic. I bought it feb, 12 2017 and drove it out of the garage feb, 11 2017. Sorry i could not get the pics upright

You've done a pile of work. It looks great now. Thanks for sharing the pics

I just saw a pair of these sell to high bid $610. You can't resurrect iron heads for that.
https://www.ebay.com/itm/Chevy-396-4....c100011.m1850
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I had a '69 Nova in High School. I love those cars.