Took the heads off - Clean up?
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Took the heads off - Clean up?
Took the stock heads off to replace the lifters during my cam swap and was wondering how I should go about cleaning them up ...
Pieces of the head gasket are still on the block and the head ... should I just lightly sand these off and call it a day, or send the heads out to get professioanlly cleaned? maybe even mill them a bit?
thanks
Pieces of the head gasket are still on the block and the head ... should I just lightly sand these off and call it a day, or send the heads out to get professioanlly cleaned? maybe even mill them a bit?
thanks
#2
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Either that or just send them to a shop, have them cleaned (shaved .003>.005) and reassembled with new springs and valve seals). This of course if you have a cam that would allow a slight shave without affecting PTV. (if that is the case you should flycut anyways)
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Thanks for the suggestions guys.
It is a TR230 Cam with a Patriot Gold Spring kit. I dont think there should be any PTV issues.
Originally Posted by PREDATOR-Z
Either that or just send them to a shop, have them cleaned (shaved .003>.005) and reassembled with new springs and valve seals). This of course if you have a cam that would allow a slight shave without affecting PTV. (if that is the case you should flycut anyways)
It is a TR230 Cam with a Patriot Gold Spring kit. I dont think there should be any PTV issues.
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I vote for a .030" mill. Patrick G.'s experience before says that'll fit and give you a 62cc chamber.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
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Originally Posted by Studytime
I vote for a .030" mill. Patrick G.'s experience before says that'll fit and give you a 62cc chamber.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
Ill be using stock GM gaskets.
thanks again guys,
#7
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Originally Posted by Studytime
I vote for a .030" mill. Patrick G.'s experience before says that'll fit and give you a 62cc chamber.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
With a thin gasket, that'll give you ~11.1:1 compression and will make that 230/224 cam even torquier.
Ben T.
.030 mill = 6 cc
That is a 60cc chamber, add a thin gasket like .040 and that is like a 57cc chamber. Overboard on PTV and SCR/DCR
.020 mill with stock gasket will be fine and plenty clearance.
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Originally Posted by PREDATOR-Z
.005 = ~ 1cc
.030 mill = 6 cc
That is a 60cc chamber, add a thin gasket like .040 and that is like a 57cc chamber. Overboard on PTV and SCR/DCR
.020 mill with stock gasket will be fine and plenty clearance.
.030 mill = 6 cc
That is a 60cc chamber, add a thin gasket like .040 and that is like a 57cc chamber. Overboard on PTV and SCR/DCR
.020 mill with stock gasket will be fine and plenty clearance.
That puts you at around 11.1 SCR and 8.55 DCR.
PTV will still be within safe street limits. Remember, this cam has no advance ground in.
Ben T.
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Also, TEA states the same thing I just did. A .030" mill for a 62cc chamber.
Look at "Specs, Notes:" under the first item listed on this page;
http://totalengineairflow.com/products/gmhead/gmls1/
I would assume that TEA uses an accurate burret to CC their heads.
Ben T.
Look at "Specs, Notes:" under the first item listed on this page;
http://totalengineairflow.com/products/gmhead/gmls1/
I would assume that TEA uses an accurate burret to CC their heads.
Ben T.
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Originally Posted by Studytime
How do you figure? Using .006" per CC you knock off 5 cc's of combustion space for a total of 66.67-5 = 61.67, with will be roughly 62cc. That with a .042" gasket will not be overboard on an otherwise stock motor.
That puts you at around 11.1 SCR and 8.55 DCR.
PTV will still be within safe street limits. Remember, this cam has no advance ground in.
Ben T.
That puts you at around 11.1 SCR and 8.55 DCR.
PTV will still be within safe street limits. Remember, this cam has no advance ground in.
Ben T.
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Also, refer to this thread back from 2002;
https://ls1tech.com/forums/showthrea...highlight=2.02
Ben T.
https://ls1tech.com/forums/showthrea...highlight=2.02
Originally Posted by Patrick G
I have ported LS1 heads milled .060". The reason I'm having to run valve reliefs in my pistons is because of the large 2.055" valves. P to V was tight with 2.02 valves and it was too close with 2.055 valves. If you run 2.02 valves and run heads milled .050" or less, you should be fine.
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Originally Posted by brad8266
You are using .006 and predator used .005 per cc. And then you posted .0075 from TEA to prove it, lol. Thats 3 different answers.
Also, TEA's number and my number (final chamber volume) are very close. Where did you get .0075" from?
Ben T.
#14
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60.67 cc you're correct LS1 is 66.67.
But that is why I put ~ sign in front of .005
Better mill, measure chamber and mill again if necessary to achieve desired chamber volume.
Regarding PTV, are you judging that by chamber size or valve drop reduction?
Also for .006 values what are you using? TR230/224 are 281/275
But that is why I put ~ sign in front of .005
Better mill, measure chamber and mill again if necessary to achieve desired chamber volume.
Regarding PTV, are you judging that by chamber size or valve drop reduction?
Also for .006 values what are you using? TR230/224 are 281/275
Last edited by PREDATOR-Z; 04-16-2007 at 12:42 PM.
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Originally Posted by Studytime
Well, Brad in response to your comment let me just say that ALL THREE are different than what Predator used.
Also, TEA's number and my number (final chamber volume) are very close. Where did you get .0075" from?
Ben T.
Also, TEA's number and my number (final chamber volume) are very close. Where did you get .0075" from?
Ben T.
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so, back to the origin question. if you are worried about milling your heads then use the green pad. (scoth prite) on heads and block. if you can get something with a straight edge or even glass to check heads that should work as well.
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Originally Posted by PREDATOR-Z
60.67 cc you're correct LS1 is 66.67.
But that is why I put ~ sign in front of .005
Better mill, measure chamber and mill again if necessary to achieve desired chamber volume.
Regarding PTV, are you judging that by chamber size or valve drop reduction?
Also for .006 values what are you using? TR230/224 are 281/275
But that is why I put ~ sign in front of .005
Better mill, measure chamber and mill again if necessary to achieve desired chamber volume.
Regarding PTV, are you judging that by chamber size or valve drop reduction?
Also for .006 values what are you using? TR230/224 are 281/275
I was judging PTV clearance by valve drop reduction taking into account if more material was removed off the deck of the heads AND a larger valve was used on Patrick G's car, then a smaller valve and a thicker head deck should clear. That seems like perfectly sound logic to me.
If I was running a TR230, I would mill .030" and use a .042" head gasket even after everything that's been discussed. I've assisted in the build of a TR230 62cc CNC LS6 combination that worked very well.
Ben T.
#18
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Originally Posted by Studytime
The advertised values I was using was 283* (If I remember correctly). That's what came off of the cam doctor, and I feel is more accurate then adding XX degrees to duration at .050".
So are the values I gave. actualy they are a bit less, I rounded of
I was judging PTV clearance by valve drop reduction taking into account if more material was removed off the deck of the heads AND a larger valve was used on Patrick G's car, then a smaller valve and a thicker head deck should clear. That seems like perfectly sound logic to me.
If I was running a TR230, I would mill .030" and use a .042" head gasket even after everything that's been discussed. I've assisted in the build of a TR230 62cc CNC LS6 combination that worked very well.
If I was running a TR230, I would mill .030" and use a .042" head gasket even after everything that's been discussed. I've assisted in the build of a TR230 62cc CNC LS6 combination that worked very well.
I had milled some 241s before, but I can't remember what was the 1cc relative to mill.
Anycase no 100% argument on my part, I would still measure to be sure. Of course you know me, I'm talking about .080/.100 margins of safety.
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Thanks for all the input so far
I took the heads to a machine shop to clean up, put the new dbl springs in, and possibly port mildly.
Considering I will be using stock GM Gaskets, I am thinking milling either .010 or .020 and calling it a day
I took the heads to a machine shop to clean up, put the new dbl springs in, and possibly port mildly.
Considering I will be using stock GM Gaskets, I am thinking milling either .010 or .020 and calling it a day
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Originally Posted by Studytime
I've assisted in the build of a TR230 62cc CNC LS6 combination that worked very well.
Ben T.
Ben T.
I agree, measure with a degree wheel and know for sure.
jinxedz, if you're trying to decide between a .020" or .010"- go with the .020" mill. Compression is your friend. It'll even idle better (smoother) if you can get the compression up some.
Ben T.