Question about different cylinder head castings
06-14-2008, 10:47 PM
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Re: Best LS cylinder heads? l92?AFR?LQ9?
i have a chevy 350 im trying to find the best heads to use. i dont have the money but i do already have 2 different set of heads sitting around. i have the HO 305 heads out of the 305 tpi motor with casting number 14101081, then i also have a 327 i was building and i have the heads off it there are the 2.02 or what ever heads the camel hump heads with casting number 3890462. i know the camel hump heads don't have the assessory holes and im not worried about it. just trying to find the best heads to use. also im sure i could dril some holes for the PS pump and what not. any ways can anyone help?
06-14-2008, 11:13 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The best heads to use? Depends upon what the car will be used for.
Street use, the 081's with 1.94" intake valves installed and basic port clean-up would be pretty hard to beat. The other possibility is a set of Vortec heads.
462 heads are for collectors.
{By the way, I moved this from where you posted it because your question has nothing to do with LS1 heads or an LS1 engine swap.)
Street use, the 081's with 1.94" intake valves installed and basic port clean-up would be pretty hard to beat. The other possibility is a set of Vortec heads.
462 heads are for collectors.
{By the way, I moved this from where you posted it because your question has nothing to do with LS1 heads or an LS1 engine swap.)
06-14-2008, 11:18 PM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Question about different cylinder head castings
The old 462 heads were a good performance head 30 years ago but by today's standard, there are much better factory heads which will out perform it.
The 462 head isn't worth that much except to collectors but it also depends on if anything has been done to it. They didn't all come with 2.02/1.60 valves and if that head has the larger valves, it won't work in the small bore of your 305 block. You already mentioned that it doesn't have accessory bolt holes which can be a problem when mounting alternator, power steering pump etc. If it doesn't have screw in rocker studs then it probably hasn't been modified meaning it will need bigger valves, screw in studs which needs the stud bosses machined off, larger spring pockets for bigger springs, new valve guides etc. By the time you're done paying for all these modifications to make them a better head, you can buy aftermarket heads cheaper and they'll be better right out of the box.
The 462 head isn't worth that much except to collectors but it also depends on if anything has been done to it. They didn't all come with 2.02/1.60 valves and if that head has the larger valves, it won't work in the small bore of your 305 block. You already mentioned that it doesn't have accessory bolt holes which can be a problem when mounting alternator, power steering pump etc. If it doesn't have screw in rocker studs then it probably hasn't been modified meaning it will need bigger valves, screw in studs which needs the stud bosses machined off, larger spring pockets for bigger springs, new valve guides etc. By the time you're done paying for all these modifications to make them a better head, you can buy aftermarket heads cheaper and they'll be better right out of the box.
06-19-2008, 02:50 AM
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Re: Question about different cylinder head castings
usually heads are expensive as hell i went here and i dont believe it tell me what u guys think, http://store.summitracing.com/partde...5&autoview=sku
if its to good to be true im getting me a set
if its to good to be true im getting me a set
06-19-2008, 05:19 AM
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Re: Question about different cylinder head castings
The problems with those vortecs are numerous. Mostly it's that they're completely stock. Also, that price is just for 1 head.
Stock vortecs have several nagging issues to take care of before they're really ready for primetime.
1. Press in studs. Any serious cam I think should need some screw in studs. Drilling and pinning the studs is all the rage around here if you want to try that, but I'm not too familiar with it or how difficult it is to do. It is cheap, though.
2. You're heavily limited for what kind of cam lift you can handle. I think the danger zone is around .460-.480 lift, which is right at the threshold of the low end of stout cams.
3. You gotta buy a special intake for it. No exceptions. None. You WILL have to buy a special intake for it. So add in another $150-$250 for that.
THey're good heads, though. I went with Vortecs for my build, but since I've had tons of bad luck I've got to do it all over agian for the 3rd time, so I have no direct experience with how much power they're gonna make.
Knowing what I know now, I'd try to find a way to get a dished piston that would get those 081 heads into the mid 9 compression ratio range. a +12 cc dish piston by my ballpark estimates will net you about a 10:1 compression ratio. I found a +23cc piston, though, that would get you 9.1:1 and a +18cc that will get around 9.5:1.
Those will change slightly with different head gasket thicknesses overboring. I assumed a 4.000 inch bore.
But I'd go for the +18cc Keith Black pistons and use the 081's, zero deck the block, and use a .040 inch head gasket and with even a slight overbore you're right in that 9.5:1 range which I've always used as a ball park target for a street motor running premium.
But I'd see how much it would cost to put some bigger valves in those heads (maybe 1.98 intake and 1.60 exhaust or so) before I decided to use them. New valves can cost a small fortune, so you may end up better off with something else.
Stock vortecs have several nagging issues to take care of before they're really ready for primetime.
1. Press in studs. Any serious cam I think should need some screw in studs. Drilling and pinning the studs is all the rage around here if you want to try that, but I'm not too familiar with it or how difficult it is to do. It is cheap, though.
2. You're heavily limited for what kind of cam lift you can handle. I think the danger zone is around .460-.480 lift, which is right at the threshold of the low end of stout cams.
3. You gotta buy a special intake for it. No exceptions. None. You WILL have to buy a special intake for it. So add in another $150-$250 for that.
THey're good heads, though. I went with Vortecs for my build, but since I've had tons of bad luck I've got to do it all over agian for the 3rd time, so I have no direct experience with how much power they're gonna make.
Knowing what I know now, I'd try to find a way to get a dished piston that would get those 081 heads into the mid 9 compression ratio range. a +12 cc dish piston by my ballpark estimates will net you about a 10:1 compression ratio. I found a +23cc piston, though, that would get you 9.1:1 and a +18cc that will get around 9.5:1.
Those will change slightly with different head gasket thicknesses overboring. I assumed a 4.000 inch bore.
But I'd go for the +18cc Keith Black pistons and use the 081's, zero deck the block, and use a .040 inch head gasket and with even a slight overbore you're right in that 9.5:1 range which I've always used as a ball park target for a street motor running premium.
But I'd see how much it would cost to put some bigger valves in those heads (maybe 1.98 intake and 1.60 exhaust or so) before I decided to use them. New valves can cost a small fortune, so you may end up better off with something else.
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