Printable View
I have a 69' 327 out of an Impala that I'm going to put in my 67' Malibu. I was thinking of using the GM Iron vortec heads. These seem like a bargain for 500 bucks a pair. I know i'll need a vortec intake also. I was wondering about which cam to use.This is just going to be a fun cruiser with midrange torque the goal.The powerglide is staying also.
Am doing something similar here, usine edelbrock e-tec alum vortec heads. Something like the ZZ4 profile..
or try this -
http://www.sallee-chevrolet.com/Chev...ckV8s/330.html - iron headed 350 with cam lited and dyno profile
Looks like there is already a thread on Vortec SBC heads. Although I have built several engines I am now building my first SBC 350. After a vigorous discussion of two-bolt versus four-bolt blocks I am going to build up my '76 Corvette two-bolt for my '29 Ford roadster (in progress). The problem is after I use 9:1 cast pistons (0.030 over) and a low rpm torque cam I will end up with a pretty tame 350 using the original 882 heads rebuilt. How "bad" are the 882 heads if I only want torque with a 2.79 rear gear? I have a set of double-hump 461 bare heads but I don't want to use them because they have 64 cc chambers and I want to avoid having to use 92 octane fuel and keep the C.R. around 9:1. Now I read in several places that I can buy Vortec heads ready to bolt on (? where ?) and that I can get close to 400 H.P. with these heads and a mild cam along with a Vortec-compatible intake. Here is the problem. The Vortec heads have 64 cc chambers, right? So I am right back looking at C. R. around 10:1. Should I use dished pistons with the Vortec heads and what are you doing about the high Compression Ratio? So far I have found the comments from this site very helpful. By the way why don't you (the site) set up a set of standard links for new members? I only found the old, very complete thread on reducing pinging recently. If a new member where immediately shown come of these links that would be very helpful. Back to Vortec heads, how do you handle the high C.R. ?
Don Shillady
Retired Scientist/teen rodder
Sorry Racerx to highjack your thread,
Don,
One thing to consider for getting your compression down using the 64 cc heads is to use a thicker head gasket. I did a compression caculation using the 64 cc heads assuming a .020 deck height, a flat top piston with 3 cc valve reliefs on a 4.030 bore a .040 head gasket thickness with the head gasket bore at 4.1 and a 3.48 stroke and came up with the 10:1 compression you stated. But I changed the thickness of the head gasket to .060 and that brought the compression down by .5 to around 9.5. You can get even thicker head gaskets than .60 and lower the compression even more, it will also increase your quench area and give you better combustion. One thing to also consider is a 10:1 compression ratio isn't really that high for high octane pump gas, especially the 93. I don't think you will have a pinging problem at that compression unless you run a cam where the intake valves close really early.
I am getting away with 11.5:1 on 93 pump gas now, and know a fellow that has 11.75 in an LS1 motor that runs pump gas and doesn't have a pinging problem. We both do have some pretty high duration cams in which the intake valves close pretty late thereby bringing down our dynamic compression ratios quit a bit, and that has everything to do with being able to run on pump gas with the compression figures I have.
One reason for lower compression ratio is to avoid detonation. By choosing the aluminum heads the heat is drawn off fast enough that you can run 10:1 on pump gas without an issue.
also, so we have to run 92. No big deal as the car will not be daily driven so any additional cost is minimal. I mean, it has a whopping 400 miles since last summer on it - 2 tank fulls of gas at even 50 cent a gallon more is not much more than a good lunch and less than a case of beer.:)
Summit Racing has the Edelbrock E-tec heads in two 'styles', both Vortec, for about $1000 a set complete. We are goind with a edelbrock air gap intake and an edelbrock 4 bbl (1404?? i can't recall right now, the 600 cfm one)
chris
Here is a run down on the engine in my 32 Ford roadster:
76 Chevy two bolt block bored .040 over and "zero" decked.
Vortec heads.
Edelbrock Performer intake, carb, and RV cam.
KB dished pistons
FelPro 1003 head gaskets (.039 thick)
Estimated CR is 9.2/1 (per the KB calculator).
Runs fine on 87 gas. Think the tight quench has something to do with that.
Lots of torque. I am running a 350 transmission and 3.25 gears. At speed it feels like it wants another gear. So I think it would perform well with a 3.00 or 2.80 rear gear.
What I don't like about the Vortec heads: Valve covers and intake do not really look all that "taditional". If I wre doing it again I would consider street replacement heads. The Moon valve covers I used cost $100 more than the same style for older heads. Also, if you plan to run a high lift cam you will need about $150 in machine work, $80 iworth of stronger springs, and $20 worth of new seals. All in all, I dont think the Vortec heads are that great of a bargain.
Now for the good news. Chevy is offering a cast iron Vortec head with both vave cover patterns and both intake manifold patterns. They are fore the races and sell for about $600 a pair bare. With valves and springs they are competitive with after market cast iron performance heads.
Stay away from the older heads. I have a set of Power Pack heads in the shop that are pretty much junk. They don't have hardened seats and the valves have literally eaten there way into the heads. Any old time cast iron head is going to have the same problem sooner or later. Heads from later, unleaded gas era cars, have hardened seats. If you are going to us an OEM head make sure you get ones with hardened seats. It may not be an issue with cars that are only raced. But if you are building for the street you need hardened seats.
Bib_Overalls:
That is a great answer complete with picture, thanks a LOT for the information!
Don Shillady
Retired Scientist/teen rodder
Technispector,
No doubt did I have my head up my rear on mentioning that increasing squish would help combustion effeciency when your right it's the other way around. Duh on my part.
I should have also mentioned that my my cams rpm range is from 4500 to 7600 and your absoulty right not a real friendly streeter. But I never did say that running a cam with late intake closing was changing my squish, but rather lowering my dynamic compression enough to run the lower octane gas with such high static compression. I actually run a very thin head gasket, at .031 and am looking to get an even thinner one at .021, would have gotten the thinner if I had known it was available at the time.
Thanks for catching my bad information, sorry.
Don C.
The edelbrock e-tec 'vortec' heads are set up for both bolt pattern valve covers, and complete (valves, springs, guide plates) for $1000 can handle cams up to .600 lift!
and being aluminum, they are pretty.
The vortec style valve covers are not cheap. they seal better i hear, but the cost...and you have to run stmped steel or 'special' alum rockers to clear the bolts.
hey screamer63_1979 do u know anyone that makes vortec heads that will fit oldintakes? i recent got a 87 trans am tpi for parts runs like new ..i plan on putting the tpi in my el camino with factory wires and computer after the car is running nice i will start the mods but i had in mind to have the vortec heads .... any help pls
i heard about a plate that would fit vortec heads found the page and its about $399
early 90s is when GM switched over - my understanding is the vortec intake bolts are at a different angle, so if that is all then teh bolt holes in the intake shold be able to be drilled...not sure though - the angles or some such might be different where the head meets the intake. the exhust is the same, the block is the same.
try calling edelbrock or maybe summit tech support and tell them you have the e-tec 170 heads and want to put the TPI intake on there and see what they asay. the e-tec is edelbrock's vortec head.
a guy at the local advance store has a tbi set up off a 350 vortec motor - heads, intake, tbi - all of it, for i think $250. 724-774-8150 but i don't have his name, sorry. i thenk he is even throwing in the computer - it is from a chevy truck and he is putting in a carb'd big block. some coworker should be able to identify him from that info. he was a skinny guy.
Give scoggin dickey part center a call at !-806-798-4108 they can help you with questions you may have with vortec heads.