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Discussion Starter · #1 ·
Ok..its about time to get a set of heads for my 350 v8 freshin up! I looked up my current head casting numbers and I have 3986388x which after looking it up is for a 68-79 350 V8 with 1.72/1.50 and 76cc's. So my question is.... i plan on running a Tunnelram with two 500 cfm Holleys and also a Comp cams thumper cam. I also have fenderwell headers and a complete MSD ignition system. So with so many heads out there which would be the best heads for my application. I also am running a Muncie 4 speed. Looking for best bang for the buck...so what do you all think??
:p3:
 

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No head had a productionrun of 68-79. in 69-70 they had 186, 041 with 4 barrel and 441 Truck all good by 71-72 the 487 and 993 are available followed by the 882 then junk called 624 in 79-79. Thatsoff the top of my head.
 

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Discussion Starter · #3 · (Edited)
No head had a productionrun of 68-79. in 69-70 they had 186, 041 with 4 barrel and 441 Truck all good by 71-72 the 487 and 993 are available followed by the 882 then junk called 624 in 79-79. Thatsoff the top of my head.

I dont know about that..all I did was look up the head casting numbers on the web and the numbers I quoted is what my casting numbers gave me??? The head came on both the 307 v8 and the 350 v8 which I have...You need to check the numbers again as so far 5 different web sites have confirmed what I said!
 

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Let's start with the worst last. Your current heads are just about the lowest performance choice you could make.

You either need some camel hump heads (probably not best for the $$ unless you stumble onto something), or some Vortec 350 heads if you want used cast iron heads.

Stepping up from there, you could go with new Vortecs, Dart or World cast iron, or any of a number of aluminum heads.

Best buy for the buck also means they need to meet expectations, and you didn't tell us much on expectations.
 

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Discussion Starter · #5 ·
No head had a productionrun of 68-79. in 69-70 they had 186, 041 with 4 barrel and 441 Truck all good by 71-72 the 487 and 993 are available followed by the 882 then junk called 624 in 79-79. Thatsoff the top of my head.

I dont know about that..all I did was look up the head casting numbers on the web and the numbers I quoted is what my casting numbers gave me??? It also said it was a Truck motor??
 

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Discussion Starter · #6 · (Edited)
Expectation..hummmmmm
Well of course I want more power as in HP, but its a street motor that might see a 1/4 mile run now and again Lol. I also want aluminum and I want to keep the old style valve covers ( I don't want to use the center bolt covers so Vortecs are out). Looking for more compression so since I have crappy 76cc I guess I can go to a 64 cc ( or 50cc head) for better compression (is that correct??). I also need the accessory holes in the front of the heads so the old style power packs are out( I don't want to drill them out!!). Hope this helps narrow the list..i am not that knowledgable about head choice at all!!! Thanks
 

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You probably need to see if you have flat top or dished pistons before picking out heads and camshaft that will work with pump gas ( unless you want to run race gas/octane boosters etc. ),

For a example a 350 std bore with flat top pistons with 5.5 cc reliefs and 64 cc with a steel shim .015, 4.1" dia head gasket and the piston top down .025" in the hole will net around 10.2 to 1 , 50 cc heads give 12.2 to 1 ,

pistons with a 13 cc dish will be 9.39 with 64 cc heads and 11 to 1 with 50 cc heads.

with 76cc heads and 13 cc dished its around 8.36 to 1, flattops is 9.15

Regards, Robert
 

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Discussion Starter · #8 ·
Thanks Robert great info...I am pretty certain that I have flat top pistons as the engine was the stock 350 from a Truck when I purchased the car. If the stock heads are any indication then this is a pretty mild engine with no performance upgrades other than what I did...(It does have a Holley 4 Barrel and Edelbrock intake and headers). The 4 barrel and intake were on the car. So I am guessing the pistons are flat top so looks like I should go with the 64 cc Heads 2.02/1.60. I have new comp cam valve springs that will handle a 500 lift cam, but have sen that most Aluminum performance heads have the needed valve springs all ready installed. Thanks for some great info.
 

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Thanks Robert great info...I am pretty certain that I have flat top pistons as the engine was the stock 350 from a Truck when I purchased the car. If the stock heads are any indication then this is a pretty mild engine with no performance upgrades other than what I did...(It does have a Holley 4 Barrel and Edelbrock intake and headers). The 4 barrel and intake were on the car. So I am guessing the pistons are flat top so looks like I should go with the 64 cc Heads 2.02/1.60. I have new comp cam valve springs that will handle a 500 lift cam, but have sen that most Aluminum performance heads have the needed valve springs all ready installed. Thanks for some great info.
Your probably wrong on the pistons you have. I have never taken apart a stock chevy truck 350 (70-80 era)that had flat tops in it. they were all dished.
 

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Discussion Starter · #10 · (Edited)
Your probably wrong on the pistons you have. I have never taken apart a stock chevy truck 350 (70-80 era)that had flat tops in it. they were all dished.
Actually Thanks...I typed in the wrong piston..I meant Dished not Flattop as you stated, I am also sure it has the Dished not flattops!! So I can probably go with the 64cc and still run pump gas and get pretty darn close to 10 to 1 (9:39). Overall not to bad for a mild street build. The Thumper cam will work great with the 64cc and the Tunnel ram will work great with the 2.10/1.60..Not bad if I am thinking it through right??
 

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Actually Thanks...I typed in the wrong piston..I meant Dished not Flattop as you stated, I am also sure it has the Dished not flattops!! So I can probably go with the 64cc and still run pump gas and get pretty darn close to 10 to 1 (9:39). Overall not to bad for a mild street build. The Thumper cam will work great with the 64cc and the Tunnel ram will work great with the 2.10/1.60..Not bad if I am thinking it through right??
Actually the thumper cam will sound good but that is about it . they actually perform weakly compared to a lot of other grinds out there. they were designed to do 1 thing only, sound lumpy. Everyone i have put in a customers car has came back out and gone on ebay due to customer dissapointment in performance. you would be way better off with a comp extreme 270. just my opinion.
 

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Your probably wrong on the pistons you have. I have never taken apart a stock chevy truck 350 (70-80 era)that had flat tops in it. they were all dished.
A 70 Chevy truck was common to have 441 castings and flat top pistons, this accounted for the 9-1 vs 8.5-1 comp that started in 71. My brother in law has a 70 that his father bought new and it was virgin when we pulled it down. Every one that I have parted out has been this way and that a lot of trucks.
 

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Discussion Starter · #13 ·
Well Heck USA1...Guess now I am gonna have to wait till I tear it down to see what piston I actually have..lol

Hotrodg726- I guess if I lose some HP with the Thumper I will be OK with it as long as I get the Thumpty-Thump sound..LOL
 
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