How Much HP Will it make??
Le Mans Master
Joined: Mar 2008
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From: Oxford MA-----You just lost the game!!!!
Be weary on buying cheaper heads (trust me). 
Make sure all the valves seat right if you buy them assembled and check them over 100%. I can tell you from my nightmare, cheap heads are aimed at those that just slap them on their cars and don't know any better. That being said, I did look at the Flo-Teks that Scotty is pointing out - but very little reviews on their use.
Make sure all the valves seat right if you buy them assembled and check them over 100%. I can tell you from my nightmare, cheap heads are aimed at those that just slap them on their cars and don't know any better. That being said, I did look at the Flo-Teks that Scotty is pointing out - but very little reviews on their use.Scott
Melting Slicks
Joined: Aug 2012
Posts: 3,487
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From: Titusville Florida
It's true, I don't have any actual experience with these heads, I'm only going by the fact that they are offered by an outfit that has a pretty good reputation. (Speedway Motors) I am planning on using a set of these heads pretty soon, and have been looking for reviews also, but they are very few. Haven't really heard anything bad about them, though.
Scott
Scott
"I have a set of these heads and the intake ports are off alignment wise,they do not match gaskets or intake ports,I had to port match mine to match the felpro gaskets,Its in the shape of an L where the ports dont match.I just got my engine running and it seems powerfull though.They relly need to fix this problem Though cant beat the price Bolt holes are not helicoiled either ,like my edelbrock ones were Good for the price"
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
Likes: 2
From: Illinois
OK guys, I've been away for a couple days and I see there has been alot of posts here. Thanks for your input.
First let me say that due to overwhelming concensus re: heads. I will upgrade from my stock set. You've all built a good case and I totally agree, thanks. I took a look at the Flo-Tek's which were suggested and I like the price and the fact that one of their two suggested cams is the one I have purchased, (Comp #12-210-2).
Any further comments on those heads is appreciated. Also I have PM'd tpi 421 vette regarding his AFR's.
Below I'll respond to various posts and get caught up.
Thanks again, I'm here for all the reasons you've pointed out.
First let me say that due to overwhelming concensus re: heads. I will upgrade from my stock set. You've all built a good case and I totally agree, thanks. I took a look at the Flo-Tek's which were suggested and I like the price and the fact that one of their two suggested cams is the one I have purchased, (Comp #12-210-2).
Any further comments on those heads is appreciated. Also I have PM'd tpi 421 vette regarding his AFR's.
Below I'll respond to various posts and get caught up.
Thanks again, I'm here for all the reasons you've pointed out.
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
Likes: 2
From: Illinois
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
Likes: 2
From: Illinois
No mention of the compression ratio by the OP but even with a 9:1 compression he is retaining the L-48 heads with the smaller values, not the L-82 882 heads with the bigger valves. He also is using a cam with .454/.454 which is not quite the L-82 cam with .450/.460, 222 duration, 114 LSA so I stand by my original HP estimate.
The HP drop in ratings occurred in 1972 when all engines were rated as NET instead of the misleading GROSS number. The 71 LT-1 with 9:1 compression with the bigger valve heads and a different cam than the L-82 was rated at 330 GROSS HP, the 72 LT-1 (same engine as 71) was rated at 255 NET HP and the 74 L-82 with the L-82 cam, 882 heads, and 9:1 compression was rated at 250 NET HP. 230-240 NET HP with the OP's setup looks about right, optimistically.
He needs MUCH BETTER heads, a roller cam (ideally) and more compression to hit higher HP-NET/GROSS. I am hoping for 310-325 RWHP/380-400 Gross HP (coming up from the Stock L-82's with no emissions, headers. 2.5 duals with a weak #6 cylinder of 233 RWHP when my L-82 is rebuilt-Short block being picked up tomorrow by the engine builder- with a Howards Roller cam (.510/.525, 219/225 duration, LSA 110), AFR 180 65 CC heads (10-10.2:1 compression with the Felpro 1094 gasket) etc. Without the compression being bumped significantly, much better flowing heads-not necessarily AFR's, and a much better aggressive cam to match the heads and cam, I don't see how he can hit those numbers, stroker or not.
The HP drop in ratings occurred in 1972 when all engines were rated as NET instead of the misleading GROSS number. The 71 LT-1 with 9:1 compression with the bigger valve heads and a different cam than the L-82 was rated at 330 GROSS HP, the 72 LT-1 (same engine as 71) was rated at 255 NET HP and the 74 L-82 with the L-82 cam, 882 heads, and 9:1 compression was rated at 250 NET HP. 230-240 NET HP with the OP's setup looks about right, optimistically.
He needs MUCH BETTER heads, a roller cam (ideally) and more compression to hit higher HP-NET/GROSS. I am hoping for 310-325 RWHP/380-400 Gross HP (coming up from the Stock L-82's with no emissions, headers. 2.5 duals with a weak #6 cylinder of 233 RWHP when my L-82 is rebuilt-Short block being picked up tomorrow by the engine builder- with a Howards Roller cam (.510/.525, 219/225 duration, LSA 110), AFR 180 65 CC heads (10-10.2:1 compression with the Felpro 1094 gasket) etc. Without the compression being bumped significantly, much better flowing heads-not necessarily AFR's, and a much better aggressive cam to match the heads and cam, I don't see how he can hit those numbers, stroker or not.
Thanks for your input.
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
Likes: 2
From: Illinois
Ya know, madam, after thinking about it, I understand the need to save money, and a set of aftermarket heads is kinda pricey, even cheap ones, but... I just can't see any sense in sinking even a nickel into those old heads. They just aren't worth it. And, BTW, if you are set on getting on the road by April 1st, you're either a day late and a dollar short, or you've got a whole year to save up and get some good heads. Just take a look at the calendar!
Scott
Scott
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
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From: Illinois
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
Likes: 2
From: Illinois
http://www.speedwaymotors.com/Flo-Te...lug,25118.html
740 bucks, and you don't need a new intake manifold or valve covers. How much are you spending to recondition those raggedy old heads? My grandpappy would have called that being a penny wise, but a dollar foolish.
Scott
740 bucks, and you don't need a new intake manifold or valve covers. How much are you spending to recondition those raggedy old heads? My grandpappy would have called that being a penny wise, but a dollar foolish.
Scott
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Le Mans Master
Joined: Oct 2007
Posts: 7,445
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From: Tennessee/Rhode Island
I did mention above the CR should be 9.21:1 with 76cc stock heads. However if I go with better flowing heads it seems most have 64cc chambers. What will that do to CR and the desire to run pump gas?? And would it be possible to use thicker head gaskets to drop the CR to a pump gas friendly ratio?
Thanks for your input.
Thanks for your input.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
http://www.carcraft.com/techarticles...head_shootout/
They were about equal to Vortec heads, power-wise, but they are aluminum, and you don't need a new intake or valve covers. They do have 1.43" wide valve springs, though, so your stock rocker arms won't clear them. Check and make sure your new rockers will clear springs that big.
Again, I would like to say that I have no actual experience with these heads, I'm just holding them up and saying "Hey, check these out!" I know, it's kind of a cop-out, but I don't want anybody to think that I am trying to pass myself off as some kind of expert, because I definitely am not. If you do choose to go with these heads, let us know how it goes.
Edit: I forgot that this is a stroker. Be advised that you will need to figure on the compression ratio. 64cc heads may be too small. Edelbrock E-street heads come in a 70cc combustion chamber, I think, as do the Dart SHP heads. You still have some homework to do.
Scott
Last edited by scottyp99; Apr 4, 2014 at 08:22 PM.
Thread Starter
Instructor
Joined: Feb 2013
Posts: 193
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From: Illinois
Car Craft had good things to say about the Flo-teks in this article:
http://www.carcraft.com/techarticles...head_shootout/
They were about equal to Vortec heads, power-wise, but they are aluminum, and you don't need a new intake or valve covers. They do have 1.43" wide valve springs, though, so your stock rocker arms won't clear them. Check and make sure your new rockers will clear springs that big.
Again, I would like to say that I have no actual experience with these heads, I'm just holding them up and saying "Hey, check these out!" I know, it's kind of a cop-out, but I don't want anybody to think that I am trying to pass myself off as some kind of expert, because I definitely am not. If you do choose to go with these heads, let us know how it goes.
Edit: I forgot that this is a stroker. Be advised that you will need to figure on the compression ratio. 64cc heads may be too small. Edelbrock E-street heads come in a 70cc combustion chamber, I think, as do the Dart SHP heads. You still have some homework to do.
Scott
http://www.carcraft.com/techarticles...head_shootout/
They were about equal to Vortec heads, power-wise, but they are aluminum, and you don't need a new intake or valve covers. They do have 1.43" wide valve springs, though, so your stock rocker arms won't clear them. Check and make sure your new rockers will clear springs that big.
Again, I would like to say that I have no actual experience with these heads, I'm just holding them up and saying "Hey, check these out!" I know, it's kind of a cop-out, but I don't want anybody to think that I am trying to pass myself off as some kind of expert, because I definitely am not. If you do choose to go with these heads, let us know how it goes.
Edit: I forgot that this is a stroker. Be advised that you will need to figure on the compression ratio. 64cc heads may be too small. Edelbrock E-street heads come in a 70cc combustion chamber, I think, as do the Dart SHP heads. You still have some homework to do.
Scott
As far as the compression ratio I called the Sealed Power Tech line (800/325-8886). They supplied my new pistons and ran the numbers on the 64cc new heads. I was told that if the pistons were .050 below deck @ TDC the CR would be 9.8:1. Based on other comments I decided I'm good with that so I went for it. I also checked with SP Tech re: push rod length and was told the std length should be fine but advised I should check for proper length anyway. Whats the best way to do that??
Thanks, Mike.
Melting Slicks
Joined: Oct 2011
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From: Sacramento California
C2 of Year Finalist (performance mods) 2019
2018 C2 of Year Finalist
How far down the hole are your pistons? You can screw up the quench if they are deep and you use a thick head gasket. .050 in the hole seems a lot...are you decking the block when you bore and clearance it?
Le Mans Master
Joined: Mar 2008
Posts: 5,948
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From: Oxford MA-----You just lost the game!!!!
You are jumping the gun, man! I think you are going to need bigger combustion chambers, or a big dish on the piston, or maybe both!
.050" piston-to-deck height, plus a .040" thick head gasket, gives you .090" quench, which sucks. Your 9.8:1 SCR will equate to a 8.15:1 DCR, which is cutting it close even with everything setup properly. That wide quench will make this combo un-doable, I think. See if you can cancel the order for the heads, and we'll make a plan, OK?
Scott
.050" piston-to-deck height, plus a .040" thick head gasket, gives you .090" quench, which sucks. Your 9.8:1 SCR will equate to a 8.15:1 DCR, which is cutting it close even with everything setup properly. That wide quench will make this combo un-doable, I think. See if you can cancel the order for the heads, and we'll make a plan, OK?
Scott
Le Mans Master
Joined: Mar 2008
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From: Oxford MA-----You just lost the game!!!!
OK, I think I have a piston for you:
http://www.summitracing.com/parts/sl...make/chevrolet
It's got the right compression height for a 383 with 5.7" rods, and a 23cc, D-shaped dish. With a .015" thick head gasket, and a .025" piston-to-deck height, they should give you a quench of .040", a 9.2:1 SCR, and 7.67:1 DCR, if you end up stuck with the 64cc heads.
Edit: It may seem counter-intuitive, but the angle-plug heads are the ones that are more likely to interfere with headers.
Scott
http://www.summitracing.com/parts/sl...make/chevrolet
It's got the right compression height for a 383 with 5.7" rods, and a 23cc, D-shaped dish. With a .015" thick head gasket, and a .025" piston-to-deck height, they should give you a quench of .040", a 9.2:1 SCR, and 7.67:1 DCR, if you end up stuck with the 64cc heads.
Edit: It may seem counter-intuitive, but the angle-plug heads are the ones that are more likely to interfere with headers.
Scott
Race Director
Joined: May 2003
Posts: 10,956
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From: California
why do you want such low compression?.... with aluminum heads your good to 11:1 in most applications on 91 octane gas,,,, your leaving a lot of free power on the bench that you can not get without doing all over again.... still would never go with a chines head, jmho,,,
Le Mans Master
Joined: Mar 2008
Posts: 5,948
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From: Oxford MA-----You just lost the game!!!!
why do you want such low compression?.... with aluminum heads your good to 11:1 in most applications on 91 octane gas,,,, your leaving a lot of free power on the bench that you can not get without doing all over again.... still would never go with a chines head, jmho,,,
Scott
Racer
Joined: May 2013
Posts: 421
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From: Chicago IL
Make sure you thoroughly inspect those heads when you get them! I am keeping my fingers crossed for you and hoping you get a good pair, but I agree with pauldana on this one.
From what I read on another forum, the Aussie thing was just an attempt to wag the dog on the true origin of the heads...they might be assembled in Australia, but are cast in China.
From what I read on another forum, the Aussie thing was just an attempt to wag the dog on the true origin of the heads...they might be assembled in Australia, but are cast in China.
Last edited by Jartanyon; Apr 7, 2014 at 07:29 PM.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Make sure you thoroughly inspect those heads when you get them! I am keeping my fingers crossed for you and hoping you get a good pair, but I agree with pauldana on this one.
From what I read on another forum, the Aussie thing was just an attempt to wag the dog on the true origin of the heads...they might be assembled in Australia, but are cast in China.
From what I read on another forum, the Aussie thing was just an attempt to wag the dog on the true origin of the heads...they might be assembled in Australia, but are cast in China.
Scott