202 heads top end kit
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202 heads top end kit
Hey everyone I'm picking up a set of 202 chevy heads off 70's or 60's corvette that had a 350 in it I'm looking to get a new top end for it cam, lifters, rockers, etc the heads do have to be rebuilt first so once I get my 194's off that's when I'll do the top end swap but what's a good set up to go with bottom end is bored 30 over with forged wesco piston with a 9.8:1 compression stroke is stock 3.48 inch bore size is 4.030
#2
Re: 202 heads top end kit
Hey everyone I'm picking up a set of 202 chevy heads off 70's or 60's corvette that had a 350 in it I'm looking to get a new top end for it cam, lifters, rockers, etc the heads do have to be rebuilt first so once I get my 194's off that's when I'll do the top end swap but what's a good set up to go with bottom end is bored 30 over with forged wesco piston with a 9.8:1 compression stroke is stock 3.48 inch bore size is 4.030
#3
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Re: 202 heads top end kit
First off, everything used you buy is going to "come off a corvette" - dont believe it for a minute. Most of those old "classic" muscle cars were pretty slow anyway. Those inflated horsepower numbers they "officially" had were SAE net horsepower which were under the most ideal of ideal situations, measured at the flywheel with no accessories, free-flowing special intake, and headers. Also a lot of them ran higher compression ratios and ran on leaded gasoline which helped them make more power - they ran into problems after leaded gasoline was phased out.
Don't get hung up on ANYTHING that came out of ANYTHING prior to 85ish. Even old school "camelhumps" have been far surpassed by modern factory Gen I heads.
There is no such thing as a "202" head. That's usually just a way that unscrupulous or just poorly informed people sell junk, crappy smogger crack-prone heads for top dollar because they have larger intake valves (2.02 inch) put into them. The intake valve size is, in the grand scheme of things, relatively unimportant in regards to performance.
Here is how it works:
Phase 1 - you get junk smogger 70s 350/400 heads for free because people cant even give them away.
Phase 2 - you install 2.02 inch intake valves in them.
Phase 3 - You sell for more than the cost of new valves
In some cases they install them and realize that going to a larger valve actually hurts power where they need it and in general realize how poorly they perform, and they sell them after that.
You need a cylinder head CASTING NUMBER, not backwoods marketing jargon. Modern heads are far superior. Some Iroc L98 heads (083) or C4 corvette L98 (113) heads would be a far better choice for a good 350.
If you're on a budget you're limited to factory heads, if you're cheap go 083 heads. If you got the cash, get 113 heads or vortec heads (906/062/060).
Edit: I see you have an 89 GTA. If you had a 350 TPI engine from the factory and reused those heads on your 355 you'll most likely LOSE performance by switching to "202" heads.
Don't get hung up on ANYTHING that came out of ANYTHING prior to 85ish. Even old school "camelhumps" have been far surpassed by modern factory Gen I heads.
There is no such thing as a "202" head. That's usually just a way that unscrupulous or just poorly informed people sell junk, crappy smogger crack-prone heads for top dollar because they have larger intake valves (2.02 inch) put into them. The intake valve size is, in the grand scheme of things, relatively unimportant in regards to performance.
Here is how it works:
Phase 1 - you get junk smogger 70s 350/400 heads for free because people cant even give them away.
Phase 2 - you install 2.02 inch intake valves in them.
Phase 3 - You sell for more than the cost of new valves
In some cases they install them and realize that going to a larger valve actually hurts power where they need it and in general realize how poorly they perform, and they sell them after that.
You need a cylinder head CASTING NUMBER, not backwoods marketing jargon. Modern heads are far superior. Some Iroc L98 heads (083) or C4 corvette L98 (113) heads would be a far better choice for a good 350.
If you're on a budget you're limited to factory heads, if you're cheap go 083 heads. If you got the cash, get 113 heads or vortec heads (906/062/060).
Edit: I see you have an 89 GTA. If you had a 350 TPI engine from the factory and reused those heads on your 355 you'll most likely LOSE performance by switching to "202" heads.
Last edited by InfernalVortex; 10-05-2011 at 02:06 AM.
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Car: 1988 Gta trans am project 1-1/2
Engine: 86 4 bolt main cammed sbc 355 hsr
Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 202 heads top end kit
First off, everything used you buy is going to "come off a corvette" - dont believe it for a minute. Most of those old "classic" muscle cars were pretty slow anyway. Those inflated horsepower numbers they "officially" had were SAE net horsepower which were under the most ideal of ideal situations, measured at the flywheel with no accessories, free-flowing special intake, and headers. Also a lot of them ran higher compression ratios and ran on leaded gasoline which helped them make more power - they ran into problems after leaded gasoline was phased out.
Don't get hung up on ANYTHING that came out of ANYTHING prior to 85ish. Even old school "camelhumps" have been far surpassed by modern factory Gen I heads.
There is no such thing as a "202" head. That's usually just a way that unscrupulous or just poorly informed people sell junk, crappy smogger crack-prone heads for top dollar because they have larger intake valves (2.02 inch) put into them. The intake valve size is, in the grand scheme of things, relatively unimportant in regards to performance.
Here is how it works:
Phase 1 - you get junk smogger 70s 350/400 heads for free because people cant even give them away.
Phase 2 - you install 2.02 inch intake valves in them.
Phase 3 - You sell for more than the cost of new valves
In some cases they install them and realize that going to a larger valve actually hurts power where they need it and in general realize how poorly they perform, and they sell them after that.
You need a cylinder head CASTING NUMBER, not backwoods marketing jargon. Modern heads are far superior. Some Iroc L98 heads (083) or C4 corvette L98 (113) heads would be a far better choice for a good 350.
If you're on a budget you're limited to factory heads, if you're cheap go 083 heads. If you got the cash, get 113 heads or vortec heads (906/062/060).
Edit: I see you have an 89 GTA. If you had a 350 TPI engine from the factory and reused those heads on your 355 you'll most likely LOSE performance by switching to "202" heads.
Don't get hung up on ANYTHING that came out of ANYTHING prior to 85ish. Even old school "camelhumps" have been far surpassed by modern factory Gen I heads.
There is no such thing as a "202" head. That's usually just a way that unscrupulous or just poorly informed people sell junk, crappy smogger crack-prone heads for top dollar because they have larger intake valves (2.02 inch) put into them. The intake valve size is, in the grand scheme of things, relatively unimportant in regards to performance.
Here is how it works:
Phase 1 - you get junk smogger 70s 350/400 heads for free because people cant even give them away.
Phase 2 - you install 2.02 inch intake valves in them.
Phase 3 - You sell for more than the cost of new valves
In some cases they install them and realize that going to a larger valve actually hurts power where they need it and in general realize how poorly they perform, and they sell them after that.
You need a cylinder head CASTING NUMBER, not backwoods marketing jargon. Modern heads are far superior. Some Iroc L98 heads (083) or C4 corvette L98 (113) heads would be a far better choice for a good 350.
If you're on a budget you're limited to factory heads, if you're cheap go 083 heads. If you got the cash, get 113 heads or vortec heads (906/062/060).
Edit: I see you have an 89 GTA. If you had a 350 TPI engine from the factory and reused those heads on your 355 you'll most likely LOSE performance by switching to "202" heads.
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Re: 202 heads top end kit
i did not know this i thought the 2 center bolt holes dont line up or do i have to just grind the hole bigger inorder for the intake to bolt on also can u tell me what year the 113 1.94 aluminum heads started i found a set off a 87 corvette with a l98 in it but when i look it up on a chevy head casting site it says they started in 88
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Re: 202 heads top end kit
Just get an intake that matches the center bolt angle.
113s are 1988 and up with vertical center bolts.
A 1987 Corvette has 128 heads with angled center bolts.
113s are 1988 and up with vertical center bolts.
A 1987 Corvette has 128 heads with angled center bolts.
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Car: 1988 Gta trans am project 1-1/2
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Transmission: 89 wc bw t5
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Re: 202 heads top end kit
Are the 128 heads the same as the 113 head in intake valve size an are they aluminum also do they have the 58cc camber
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Car: 1988 Gta trans am project 1-1/2
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Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 202 heads top end kit
Where do I find these set of heads are they on camaros an firebirds or would I have to go find a set in the bone yard an rebuild them
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Re: 202 heads top end kit
someone mentioned them before "If you're on a budget you're limited to factory heads, if you're cheap go 083 heads. If you got the cash, get 113 heads or vortec heads (906/062/060)."
im not sure if these are the right casting numbers or not.. i would check mortec casting numbers they came on trucks with 350's 97 98 style get the casting numbers though. you can tell by the bolt pattern but there are hundreds of jerks selling center-bolt swirl-port heads as vortecs so educate yourself..
these need the valve guides cut down a little when going over .475 lift but are one of the best bang for the buck heads
always use springs that will match the cam..
here are some in jegs.. http://www.jegs.com/p/GM-Performance...49896/10002/-1
Last edited by 88 350 tpi formula; 10-06-2011 at 07:47 PM.
#15
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Re: 202 heads top end kit
http://www.chevymania.com/tech/vortec.htm
I have 906 heads. 062 heads are the same thing. xxx060 is the GM part number for either of those casting numbers without special valve seats or other special installations. The hardened valve seats can be found on some 906 or 062 heads and hurt flow, so avoid them if possible, but if you end up with a head with them a good valve job will take care of it just fine. A magazine a while back got a hold of 906 heads and those particular ones happened to have the hardened exhaust seat for heavy duty trucks so they said to avoid those castings, but there are 062 heads with hardened exhaust valve seats too. Anyway if you want to read up on that read this link:
http://www.nastyz28.com/forum/showthread.php?t=56505
Two Vortec castings were used from 1996-99 on GM CK trucks ('00 in vans) and SUV's utilizing the Vortec 5700 350 engine. The #906 and #062. The #906 casting head was available in two versions. One has an Inconel exhaust seat with a single angle grind, and the other has the conventional 3-angle grind on the exhausts as per the #062. The #906 with Inconel seat does not intrude into the exhaust port. It was used primarily on the HD and 1-ton truck applications where sustained towing of heavy loads & weight up inclines could cause eventual damage to a standard induction-hardened exhaust seat from excessive heat.
The only difference between the #062 and #906 Vortec head is in the exhaust seat of the HD/1-ton truck #906 version, as described above. The #062 has a 3-angle grind on a standard induction-hardened seat, as does the non-HD #906 head. The 062 does flow slightly better on the exhaust side at low lifts but the advantage over a 906 is very slight. They both utilize back-cut exhaust valves. They both have 3-angle grind seats on the intakes with back-cut intake valves. Both heads make the same power in stock form.
The only difference between the #062 and #906 Vortec head is in the exhaust seat of the HD/1-ton truck #906 version, as described above. The #062 has a 3-angle grind on a standard induction-hardened seat, as does the non-HD #906 head. The 062 does flow slightly better on the exhaust side at low lifts but the advantage over a 906 is very slight. They both utilize back-cut exhaust valves. They both have 3-angle grind seats on the intakes with back-cut intake valves. Both heads make the same power in stock form.
Last edited by InfernalVortex; 10-06-2011 at 09:14 PM.
#16
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Re: 202 heads top end kit
Vortecs are basically the iron SBC version of the iron LT1 heads found on the B-body LT1. Good heads for the $$$ spent. They aren't no AFR heads but they are much better than factory L98 heads off a thirdgen. only issue is you need a vortec base for your TPI, or a vortec pattern intake.
#17
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Car: 1988 Gta trans am project 1-1/2
Engine: 86 4 bolt main cammed sbc 355 hsr
Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 202 heads top end kit
906 and 062 are by far the most common Vortec 64cc castings. You can always tell Vortecs because therea re only 8 bolts holding on the intake.
http://www.chevymania.com/tech/vortec.htm
I have 906 heads. 062 heads are the same thing. xxx060 is the GM part number for either of those casting numbers without special valve seats or other special installations. The hardened valve seats can be found on some 906 or 062 heads and hurt flow, so avoid them if possible, but if you end up with a head with them a good valve job will take care of it just fine. A magazine a while back got a hold of 906 heads and those particular ones happened to have the hardened exhaust seat for heavy duty trucks so they said to avoid those castings, but there are 062 heads with hardened exhaust valve seats too. Anyway if you want to read up on that read this link:
http://www.nastyz28.com/forum/showthread.php?t=56505
I think some of the ones sold have an 060 casting number like the part number, but Im not sure. These would be ones you buy directly from GM I think if they exist.
http://www.chevymania.com/tech/vortec.htm
I have 906 heads. 062 heads are the same thing. xxx060 is the GM part number for either of those casting numbers without special valve seats or other special installations. The hardened valve seats can be found on some 906 or 062 heads and hurt flow, so avoid them if possible, but if you end up with a head with them a good valve job will take care of it just fine. A magazine a while back got a hold of 906 heads and those particular ones happened to have the hardened exhaust seat for heavy duty trucks so they said to avoid those castings, but there are 062 heads with hardened exhaust valve seats too. Anyway if you want to read up on that read this link:
http://www.nastyz28.com/forum/showthread.php?t=56505
I think some of the ones sold have an 060 casting number like the part number, but Im not sure. These would be ones you buy directly from GM I think if they exist.
#18
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Re: 202 heads top end kit
Before I knew what heads casting #'s and cam profiles were and before I came to this site I once bought a Re-man for my then "new" car, my GTA.
The reman was supposed to be a direct replacement L98. What it really was was a 350 TBI motor with the wrong cam and the wrong heads. The place who built the engine basically said it was a direct replacement because it bolted in. And i was SOL. That engine thanks to the cam and heads differences never passed emissions.
Now i know better. At the time though my dad was helping me to get a new engine, and he didn't want a used engine. I would have been better off with a used L98, at least the cam and heads would have been right for the chip in the car.
The reman was supposed to be a direct replacement L98. What it really was was a 350 TBI motor with the wrong cam and the wrong heads. The place who built the engine basically said it was a direct replacement because it bolted in. And i was SOL. That engine thanks to the cam and heads differences never passed emissions.
Now i know better. At the time though my dad was helping me to get a new engine, and he didn't want a used engine. I would have been better off with a used L98, at least the cam and heads would have been right for the chip in the car.
#19
Re: 202 heads top end kit
I am still confused on the point that this O/P bought relative expensive forged pistons,but seems want to try to get by with whatever heads.Back in the day we where thrilled with the thought of oem 202 heads that produced 375 to 400 hp.And those where ported to as much as the oem castings would allow by Mondello.Aside from the fact 202's that where not cracked made them scarce,and the fact the casting did allow for any serious flow numbers,is the main reason why aftermarket companies came in being.
The truth is when I started planing for my 383 build,I was considering Vortec heads from GMdirect.But as I started to machine the block and consider SCR's with head CC's,I changed up to RHS heads.And yes I know tons of you guys are AFR fans,but I do think you get a better deal with RHS.
Cast VS Aluminum.If your trying to drop SCR by using a aluminum for todays gas,ok then use them.It is a band-aid fix to a wrong piston selection/poor planing for decking the block.And it is expensive.If your thought is a wt savings on a street driven vehicle,that is just total B.S.because it just doesn't impact it that much if at all.I have been a swap meet vendor for about 20yrs buying at auctions SBC parts.We do have a keen eye while buying the same.For that whole time we have never seen used aluminum sets of heads that did not need work.Bottom line is the aftermarket cast iron sets for the long term are more durable.
Intake runner sizes.I think I have posted this before,but the formula for a rule of thumb is C.I. x .5 = about the size of a intake runner size.Using that as a baseline,you can move torque curves and peak hp's around changing the intake runners/cams.There are any number of on line dyno's that you can plug in the values to see the differences.
I am posting this for a record.This O/P bought a piston that on cold starts is going to do the forged raddled.The Icon piston design has addressed this with a offset piston pin and cost alot less.My two cents worth is there are race car parts and street parts,so you sheet build the total package for the end intended use.Some of the race rings needed on race pistons are not designed for today's gas or any street use.They are smaller in size and have less tension.So a "like Mike" for the street just does not work.I am saying that with tons of 9.90 car builds.
The truth is when I started planing for my 383 build,I was considering Vortec heads from GMdirect.But as I started to machine the block and consider SCR's with head CC's,I changed up to RHS heads.And yes I know tons of you guys are AFR fans,but I do think you get a better deal with RHS.
Cast VS Aluminum.If your trying to drop SCR by using a aluminum for todays gas,ok then use them.It is a band-aid fix to a wrong piston selection/poor planing for decking the block.And it is expensive.If your thought is a wt savings on a street driven vehicle,that is just total B.S.because it just doesn't impact it that much if at all.I have been a swap meet vendor for about 20yrs buying at auctions SBC parts.We do have a keen eye while buying the same.For that whole time we have never seen used aluminum sets of heads that did not need work.Bottom line is the aftermarket cast iron sets for the long term are more durable.
Intake runner sizes.I think I have posted this before,but the formula for a rule of thumb is C.I. x .5 = about the size of a intake runner size.Using that as a baseline,you can move torque curves and peak hp's around changing the intake runners/cams.There are any number of on line dyno's that you can plug in the values to see the differences.
I am posting this for a record.This O/P bought a piston that on cold starts is going to do the forged raddled.The Icon piston design has addressed this with a offset piston pin and cost alot less.My two cents worth is there are race car parts and street parts,so you sheet build the total package for the end intended use.Some of the race rings needed on race pistons are not designed for today's gas or any street use.They are smaller in size and have less tension.So a "like Mike" for the street just does not work.I am saying that with tons of 9.90 car builds.
Last edited by 1gary; 10-07-2011 at 01:39 PM.
#20
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Re: 202 heads top end kit
Back in the day we where thrilled with the thought of oem 202 heads that produced 375 to 400 hp.And those where ported to as much as the oem castings would allow by Mondello.Aside from the fact 202's that where not cracked made them scarce,and the fact the casting did allow for any serious flow numbers,is the main reason why aftermarket companies came in being.
Cast VS Aluminum.If your trying to drop SCR by using a aluminum for todays gas,ok then use them.It is a band-aid fix to a wrong piston selection/poor planing for decking the block.And it is expensive.If your thought is a wt savings on a street driven vehicle,that is just total B.S.because it just doesn't impact it that much if at all.I have been a swap meet vendor for about 20yrs buying at auctions SBC parts.We do have a keen eye while buying the same.For that whole time we have never seen used aluminum sets of heads that did not need work.Bottom line is the aftermarket cast iron sets for the long term are more durable.
#21
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Re: 202 heads top end kit
You're talking about whatever head you had back then that had 2.02 inch valves put in them. There's no standard "202" head. These days they just put 2.02 inch valves into craptastic smogger heads and scam people with it. There is no casting number for "202" heads, they can be anything with nearly any intake port and exhaust port, usually crappy ones since heads that are worth anything are sold as what they actually are, ie " ported 083s with 2.02/1.60 valves", not "202" heads.
A couple of advantages of aluminum are weight and better port shapes due to advantages of working with aluminum. I want aluminum heads for better weight distribution and weight cutting mostly. There are a LOT of factory OEM aluminum head applications these days too.
A couple of advantages of aluminum are weight and better port shapes due to advantages of working with aluminum. I want aluminum heads for better weight distribution and weight cutting mostly. There are a LOT of factory OEM aluminum head applications these days too.
A SBC iron head assembled is darn close to 50lbs on its own. A aluminum LT1 head which is pretty much the same thing is barely 25lbs assembled. I bought a set to have ported and the combined assembled weight with packing material in the box was 48lbs. Thats just 24lbs a head.
Saving nearly 50lbs off the TOP of a motor has some very nice benefits for those who are concerned with weight loss. It is also cheaper for people to work with aluminum and to pay other people to port it.
I think I remember Aluminum as being roughly 1/3 the weight of Iron for the same size.
#22
Re: 202 heads top end kit
About 20yrs in 9.90 cars.Formula for wt is 100lbs savings is about equal to 10 hp.Bare bones truth.Read less the ad's in the comic books and please do more deductive logic.The idea that wt savings on a street rod is pure
The clean cast that is offer by RHS is more a advantage.
OEM's are building problematic Aluminum heads that is a consent repair listed in a trade mag on line Engine builders .com.Don't kid your self.OEM's to cut costs will and do anything.
What I am posting isn't a guess.It's your choice to learn from that yrs of experience or not.
The clean cast that is offer by RHS is more a advantage.
OEM's are building problematic Aluminum heads that is a consent repair listed in a trade mag on line Engine builders .com.Don't kid your self.OEM's to cut costs will and do anything.
What I am posting isn't a guess.It's your choice to learn from that yrs of experience or not.
#23
Re: 202 heads top end kit
You're talking about whatever head you had back then that had 2.02 inch valves put in them. There's no standard "202" head. These days they just put 2.02 inch valves into craptastic smogger heads and scam people with it. There is no casting number for "202" heads, they can be anything with nearly any intake port and exhaust port, usually crappy ones since heads that are worth anything are sold as what they actually are, ie " ported 083s with 2.02/1.60 valves", not "202" heads.
I do think you are nett picking terms here.Show me where I said a casting number had 202 intake valves??.In fact I spoke about Mondello heads.Right??.
A couple of advantages of aluminum are weight and better port shapes due to advantages of working with aluminum. I want aluminum heads for better weight distribution and weight cutting mostly. There are a LOT of factory OEM aluminum head applications these days too.
I do think you are nett picking terms here.Show me where I said a casting number had 202 intake valves??.In fact I spoke about Mondello heads.Right??.
A couple of advantages of aluminum are weight and better port shapes due to advantages of working with aluminum. I want aluminum heads for better weight distribution and weight cutting mostly. There are a LOT of factory OEM aluminum head applications these days too.
#24
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Re: 202 heads top end kit
About 20yrs in 9.90 cars.Formula for wt is 100lbs savings is about equal to 10 hp.Bare bones truth.Read less the ad's in the comic books and please do more deductive logic.The idea that wt savings on a street rod is pure
The clean cast that is offer by RHS is more a advantage.
OEM's are building problematic Aluminum heads that is a consent repair listed in a trade mag on line Engine builders .com.Don't kid your self.OEM's to cut costs will and do anything.
What I am posting isn't a guess.It's your choice to learn from that yrs of experience or not.
The clean cast that is offer by RHS is more a advantage.
OEM's are building problematic Aluminum heads that is a consent repair listed in a trade mag on line Engine builders .com.Don't kid your self.OEM's to cut costs will and do anything.
What I am posting isn't a guess.It's your choice to learn from that yrs of experience or not.
About 20yrs in 9.90 cars.Formula for wt is 100lbs savings is about equal to 10 hp.Bare bones truth.
Lets use an example. A 1992 Camaro Z28 with an L98. Say it weighs in at 3350lbs and has 245hp. This Camaro is moving 13.67lbs per 1HP the engine made.
So lets take the statement 100lbs is worth 10HP. How true is it? A little math and we can proove or disprove it.
So the ratio is 13.67lbs to 1HP for the Z28. If the Z28 made 10hp less, how much weight would have to be lost to equal the same performance? Well that's easy. Take your ratio of 13.67lbs per HP and multiply it by 235hp, 10hp less. To achieve roughly the same acceleration with only 235hp the Z28 would have to weigh in at ~3213lbs.
3350lbs - 3213lbs = a difference of 137lbs.
But what if we are talking a high HP car like the new Corvette ZR1. The ZR1 makes about 640hp and weighs in near 3350lbs. So that ratio comes to just 5.23lbs per HP. So if the vette made 10hp less how much lighter would it have to be to acheive the same acceleration? Easy 5.23 * 630 = 3297lbs. Thats only 53lbs.
So on on hand we have the phrase 100lbs is worth 10hp. But I just posted 2 examples that show 100lbs is not worth 10hp in all cases. On one hand 10hp is worth 137lbs, on the other its worth only 53hp.
___________________
What does this 50lbs at the the TOP and front of the car save you? Better weight distribution, braking, acceleration and handling. All to marginally small degrees but if you could test it and make the weight loss the ONLY variable you'd see small benefits everywhere.
Now take that concept and apply it to the whole car. Aluminum heads, aluminum motor. Fiberglass here, Carbon fibre there, magnesium wheels....Pretty soon those weight savings add up to a substantial amount.
OEM's are building problematic Aluminum heads that is a consent repair listed in a trade mag on line Engine builders .com.Don't kid your self.OEM's to cut costs will and do anything.
More so Performance cars do it because every pound less means more work gets done with the same power. Less weight means faster acceleration. Less weight means increased Geforce loads before tire slippage occurs. Less weight means the brakes have bleed off just that much less kinetic energy into heat and cars stop in shorter distances.
#25
Re: 202 heads top end kit
So it's all good because 100lbs doesn't equal 10 hp.Right??.So than following that logic,50 lbs doesn't matter all that much either.
Just think of 50 lbs effect the steering,traction,and over all performance.Errr-nope.It doesn't.That's silly.
Just think of 50 lbs effect the steering,traction,and over all performance.Errr-nope.It doesn't.That's silly.
#26
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iTrader: (5)
Re: 202 heads top end kit
I think you underestimate the advantages of dropping 50lbs off the front of the car when it comes to handling. It has a larger effect on lateral weight transfer than it does on acceleration or braking.
#27
Re: 202 heads top end kit
Its not about each individual weight savings but everything together. If you can save 50lbs and make the same power for nearly the same $$$ why NOT save the weight?
I think you underestimate the advantages of dropping 50lbs off the front of the car when it comes to handling. It has a larger effect on lateral weight transfer than it does on acceleration or braking.
I think you underestimate the advantages of dropping 50lbs off the front of the car when it comes to handling. It has a larger effect on lateral weight transfer than it does on acceleration or braking.
Core issue.................once again the aluminum heads long term are not as durable.Take that to the bank.$$$$$$$.And please consider we not talking about grandma driving her OEM to the grocery store.
#29
Supreme Member
iTrader: (5)
Re: 202 heads top end kit
You've done such a wonderful job of proving your point about aluminum vs iron durability. Please continue to do so. So ignoring all the crap gary brought up here's what other people have posted.
Old smog heads with 2.02 valves are only valuable if you want a boat anchor and can't find one. New heads, iron or aluminum are lightyears beyond them.
Personally, if you can afford the slight extra expense go aluminum. There isn't any reason not to. Look at the modern industry, just about EVER car out there comes with aluminum heads. Must be a reason for that.
Old smog heads with 2.02 valves are only valuable if you want a boat anchor and can't find one. New heads, iron or aluminum are lightyears beyond them.
Personally, if you can afford the slight extra expense go aluminum. There isn't any reason not to. Look at the modern industry, just about EVER car out there comes with aluminum heads. Must be a reason for that.
#30
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Car: 1988 Gta trans am project 1-1/2
Engine: 86 4 bolt main cammed sbc 355 hsr
Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 202 heads top end kit
everybody needs to get along im gonna find these aluminum heads if it takes me forever trans am is coming off the road on nov 1st so i can even start saving up for a afr heads i seen them in a summit book as long as they are aluminum an have the 55cc chambers ill be good been even thinking about dropping the tpi setup back in my gta i got a whole eldelbrock tpi intake manifold. runners, an plenum sitting down in the cellar that i can get ported as well looks like the carb days are over for me :-)
#31
Re: 202 heads top end kit
You've done such a wonderful job of proving your point about aluminum vs iron durability. Please continue to do so. So ignoring all the crap gary brought up here's what other people have posted.
Old smog heads with 2.02 valves are only valuable if you want a boat anchor and can't find one. New heads, iron or aluminum are lightyears beyond them.
Personally, if you can afford the slight extra expense go aluminum. There isn't any reason not to. Look at the modern industry, just about EVER car out there comes with aluminum heads. Must be a reason for that.
Old smog heads with 2.02 valves are only valuable if you want a boat anchor and can't find one. New heads, iron or aluminum are lightyears beyond them.
Personally, if you can afford the slight extra expense go aluminum. There isn't any reason not to. Look at the modern industry, just about EVER car out there comes with aluminum heads. Must be a reason for that.
Old dogs that stay up to date like me,hardest thing to do is to try to explain the facts of real street experiences.
#32
Supreme Member
iTrader: (4)
Re: 202 heads top end kit
Aluminum heads probably arent as durable due to the nature of aluminum, but they've been in factory Corvettes since the 80s, F-bodies since the 90s, trucks since 2000 or so. They cannot possibly be THAT bad given their abundance in OEM applications. OEMs will cheap out where they can but aluminum costs MORE than iron and more than that the OEM's have to WARRANTY their parts. If their heads start failing all over the place they're not gonna make any money.
And Im sorry I havent heard any rashes of cylinder head failures in any OEM GM application with aluminum heads. Old smogger heads I hear lots of bad things about due to quality control and thin-casting issues leading crack-prone heads, and those are generally what end up as your "202" heads...
If I ever got a used cast iron head I'd still have everything worked over. I wouldnt expect 150k mile cast iron heads to be "ready to bolt on" either.
And Im sorry I havent heard any rashes of cylinder head failures in any OEM GM application with aluminum heads. Old smogger heads I hear lots of bad things about due to quality control and thin-casting issues leading crack-prone heads, and those are generally what end up as your "202" heads...
If I ever got a used cast iron head I'd still have everything worked over. I wouldnt expect 150k mile cast iron heads to be "ready to bolt on" either.
Last edited by InfernalVortex; 10-07-2011 at 10:24 PM.
#33
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Car: 1988 Gta trans am project 1-1/2
Engine: 86 4 bolt main cammed sbc 355 hsr
Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 202 heads top end kit
ok so i tryed also finding them on autozone website but when i look up a 88-89 corvette it doesnt come up with the casting number last 3 113 its really strange is there a part number i can get to actually look them up cause if so ill get a set off of there
#34
Re: 202 heads top end kit
You seem to have a lot of experience and I definitely respect that. Props to you for being there and doing it. But a lot of your stats seem based more on outdated superstition than modern accepted fact in a lot of cases. Aluminum heads probably arent as durable due to the nature of aluminum, but they've been in factory Corvettes since the 80s, F-bodies since the 90s, trucks since 2000 or so. They cannot possibly be THAT bad given their abundance in OEM applications. OEMs will cheap out where they can but aluminum costs MORE than iron and more than that the OEM's have to WARRANTY their parts. If their heads start failing all over the place they're not gonna make any money.
And Im sorry I havent heard any rashes of cylinder head failures in any OEM GM application with aluminum heads. Old smogger heads I hear lots of bad things about due to quality control and thin-casting issues leading crack-prone heads, and those are generally what end up as your "202" heads...
The days of the camelhumps and "202" heads being the end all be all of performance are long, long gone. Aluminum is the future and the OEMs wouldnt be using it if it were that problem prone.
If I ever got a used cast iron head I'd still have everything worked over. I wouldnt expect 150k mile cast iron heads to be "ready to bolt on" either.
And Im sorry I havent heard any rashes of cylinder head failures in any OEM GM application with aluminum heads. Old smogger heads I hear lots of bad things about due to quality control and thin-casting issues leading crack-prone heads, and those are generally what end up as your "202" heads...
The days of the camelhumps and "202" heads being the end all be all of performance are long, long gone. Aluminum is the future and the OEMs wouldnt be using it if it were that problem prone.
If I ever got a used cast iron head I'd still have everything worked over. I wouldnt expect 150k mile cast iron heads to be "ready to bolt on" either.
My comparison is cast new to aluminum new aftermarket heads.I got a friend that is a huge mid west distributor that got stung with loads of defective heads and took the lost.There is a business behind the scenes in parts that most end users is not aware of.To get a feeling somewhat of what is going on there,I heavily suggest to bookmark www.enginebuildermag.com
It effects what to buy and why.The main thing to consider,well really one thing,is much of the aftermarket parts are off shore sourced and alot of it is machined off shore where the Q.C. is a serious question.
We bought and sold every brand of aluminum head you could think of and one common thread is what I posted.
#35
Re: 202 heads top end kit
After explaining my background and having face on face meets with them,I am saying the cast iron RHS heads are packed with dollar for dollar the biggest bang for your buck that will keep pace with most aluminum aftermarket heads and will out last all of them.
#36
Supreme Member
iTrader: (4)
Re: 202 heads top end kit
Our race operation in 9.90 drag cars has for yrs been in the top 4.Don't get that kind of results not being in the loop of current day tech.
My comparison is cast new to aluminum new aftermarket heads.I got a friend that is a huge mid west distributor that got stung with loads of defective heads and took the lost.There is a business behind the scenes in parts that most end users is not aware of.To get a feeling somewhat of what is going on there,I heavily suggest to bookmark www.enginebuildermag.com
It effects what to buy and why.The main thing to consider,well really one thing,is much of the aftermarket parts are off shore sourced and alot of it is machined off shore where the Q.C. is a serious question.
We bought and sold every brand of aluminum head you could think of and one common thread is what I posted.
My comparison is cast new to aluminum new aftermarket heads.I got a friend that is a huge mid west distributor that got stung with loads of defective heads and took the lost.There is a business behind the scenes in parts that most end users is not aware of.To get a feeling somewhat of what is going on there,I heavily suggest to bookmark www.enginebuildermag.com
It effects what to buy and why.The main thing to consider,well really one thing,is much of the aftermarket parts are off shore sourced and alot of it is machined off shore where the Q.C. is a serious question.
We bought and sold every brand of aluminum head you could think of and one common thread is what I posted.
Also, I completely agree with what you're saying about it being machined off shore. Blueprint Engines made a big deal about the fact that they machine their new aluminum head offering in the states - but it IS cast offshore but at least they were upfront about it. I dont think I'd have a problem buying their heads, but at the end of the day i've got Vortecs and they may not be the best heads on the planet but Im not sure the upgrade is worth the cost and time involved for the horsepower gain I would get. My camshaft is the limiting factor in my build anyway.
I dont think heads like the cheap pro comps and whatnot are a waste of money and bad, but i think you kind of play the lottery with cheap aluminum heads. AFR's and GM heads I dont worry about so much. And there are other brands I happen to know to be fairly nice stuff that I dont worry about. But the new craze for cheap aluminum heads machined by the lowest bidder will definitely cause problems like you're saying.
But I dont think quality aluminum heads are problem prone just because they're aluminum. The things you mention are issues and engineerign challenges, but they've been successfully tackled for 30 years.
Last edited by InfernalVortex; 10-08-2011 at 01:21 AM.
#37
TGO Supporter
iTrader: (2)
Re: 202 heads top end kit
It's a well sold miff. A "like Mike" street car trying to be a super gas car.
Core issue.................once again the aluminum heads long term are not as durable.Take that to the bank.$$$$$$$.And please consider we not talking about grandma driving her OEM to the grocery store.
Core issue.................once again the aluminum heads long term are not as durable.Take that to the bank.$$$$$$$.And please consider we not talking about grandma driving her OEM to the grocery store.
#38
Re: 202 heads top end kit
I lost my last post.Well things happen like that I guess.
Rest assure that the 9.90 engines are aluminum headed.But we are doing laps and pretty much at idle the rest of the time.I am saying that isn't a fair to compare that to a street car either because we are buzzing those alot while racing.Also,the 50 lbs for that application even through a small pc of the wt reduction means alot.
I do know how long oem heads have been on the market.To compare that to what we intend to do with engines isn't the same thing.I am reporting what is found in the market we use those heads.If you do agree that aluminum is a softer material,then it isn't a stretch to agree the aluminum has a harder time holding valve guides in place over time,rocker studs in place over time,holding deck surfaces flat,etc.
If you go to the RHS site to review what is offered in cast iron,I think my point will become more clear.I don't buy into the idea of 50 lbs meaning that much on a street driven vehicle.
Just check out the site and I do think you will see a bigger bang for your buck over the long run.
Rest assure that the 9.90 engines are aluminum headed.But we are doing laps and pretty much at idle the rest of the time.I am saying that isn't a fair to compare that to a street car either because we are buzzing those alot while racing.Also,the 50 lbs for that application even through a small pc of the wt reduction means alot.
I do know how long oem heads have been on the market.To compare that to what we intend to do with engines isn't the same thing.I am reporting what is found in the market we use those heads.If you do agree that aluminum is a softer material,then it isn't a stretch to agree the aluminum has a harder time holding valve guides in place over time,rocker studs in place over time,holding deck surfaces flat,etc.
If you go to the RHS site to review what is offered in cast iron,I think my point will become more clear.I don't buy into the idea of 50 lbs meaning that much on a street driven vehicle.
Just check out the site and I do think you will see a bigger bang for your buck over the long run.
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