olds 403
Edelbrock 455 heads will work but you need a taller manifold so the tops of the ports line up. Getting used #5 heads I believe is going to be tough. I got mine from a Cutlass Supreme out of a junkyard. You could check the major porters like Midwest Performance and see if they have some cores. The 4A heads are actually a good set of heads and work better than the #5's in ported form, just takes a little more work and with cast iron more work means more $$.
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Staging Lane
Joined: Jul 2006
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i just lost lost a bid on ebay for 350 #6 olds heads, and i always see 455 heads and it seems people hardly bid on those. my intake is an edelbrock perferomer #3711 but i didnt think 455 heads would bolt up.
What heads do you currently have? I think you need the 7111 manifold, I think it's the Performer RPM intake. I ran the 3711 on mine with a Holley carb. The Edelbrock carb won't fit unless you grind off the EGR.
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Staging Lane
Joined: Jul 2006
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i just have the stock heads, and stock carb, all i have is a comp cam, but i head that pre smog pump heads raise the compression a lot, and i dont really have money for the edelbrock heads.... how much you think the stock heads can take with a shot of juice? im thinking if i cant have heads getting a dry shot of nitrous
What car is this motor in, a 79 T/A? If so then yes #5 heads will bump your compression up to like 9.5:1 IIRC, stock is about 7.9:1. If you have the 4A heads the intake is fine and as good as the #5, but it's the exhaust that needs work. With an old carb motor you need to go wet and just use a plate.
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First identify your heads, the casting should be on the drivers front or middle of the head and cast into it. #8 heads are 350 smog heads from the 60's and totally suck, they were never on a 403, if they are then someone did an ill advised swap. All numbered heads are small block and lettered heads are big block. J's, and C's shouldn't be on the car unless someone did a bone head move. The reason it has no power is because your compression is so low.
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Verdad Gallardo I don't know, been a long time since I had my T/A. Figure out what you have, probably cheaper to mill your heads, hog them out and put a VJ on them. What is your budget? Why not go to a junk yard and look for Olds cars? I'm sure there are plenty since their not that popular.
Yes it would. For a G you could do a little work to your heads to make them work for you. Go to a full service machine shop and work with them to get some port work done, VJ and mill the heads. I'm guessing they are 4A heads as those we on Olds 403's from 77-79. If that's the case then you need to get some exhaust work done, new seats for larger valves, mill the heads to bump the compression and you should be good to go. 4A heads have around an 80cc chamber which is causing you to have such a low compression. Do your homework on how much to mill to bring your compression ratio up to around 9:1. That's about as high as you wanna go on pump gas and cast iron heads.
Edit: On my 79 T/A, I rebuilt my 403 with new pistons to bump compression to 8.5:1, stock 4A heads and full exhaust. Through a TH350 with a tiny stall I put down a little over 250 to the wheels. Basically on par with a stock Z.
Edit: On my 79 T/A, I rebuilt my 403 with new pistons to bump compression to 8.5:1, stock 4A heads and full exhaust. Through a TH350 with a tiny stall I put down a little over 250 to the wheels. Basically on par with a stock Z.
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Staging Lane
Joined: Jul 2006
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Thread Starter
Staging Lane
Joined: Jul 2006
Posts: 97
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well the guy said he'd sell me the heads aone for 100 bucks but he hasnt gotten back with me for the shipping, and im currently winning some other #5 heads for 76 bucks but what usually happend im never around to protect my bid once its ending and i get out bid, with the 64cc chamber how much hp do you think i would be making, im thinking like may be with the right set out around 310 to the fly wheel, or am i over estamating?
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Staging Lane
Joined: Jul 2006
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well i had the engine rebuilt like 3 years ago, and i had a comp cam put in it but i forgot what the lift is, i have to look for the build sheet they gave me. all i remember that i had extra that changed the feel the the ride was the 2500 stall converter and a shifting kit, other then that it still feels the same.
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Staging Lane
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