Best sealing head gaskets and piston notch info
#1
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Well a second spike to 260 today shows the Cometics are leaking into the coolant system. I'm going to notch the pistons while it is apart for extra clearance with the RapTr cam. How much is a good/safe notch depth?
Also what is the bar none best (and safest install) sealing head gasket for stock bore LS1? I'm not even against composite if they are the best. I knew going in based off my Buick experiences with Cometics it is rolling the dice. I lost and not looking to pull the heads again for a good period of time now.
Also what is the bar none best (and safest install) sealing head gasket for stock bore LS1? I'm not even against composite if they are the best. I knew going in based off my Buick experiences with Cometics it is rolling the dice. I lost and not looking to pull the heads again for a good period of time now.
#6
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Well a second spike to 260 today shows the Cometics are leaking into the coolant system. I'm going to notch the pistons while it is apart for extra clearance with the RapTr cam. How much is a good/safe notch depth?
Also what is the bar none best (and safest install) sealing head gasket for stock bore LS1? I'm not even against composite if they are the best. I knew going in based off my Buick experiences with Cometics it is rolling the dice. I lost and not looking to pull the heads again for a good period of time now.
Also what is the bar none best (and safest install) sealing head gasket for stock bore LS1? I'm not even against composite if they are the best. I knew going in based off my Buick experiences with Cometics it is rolling the dice. I lost and not looking to pull the heads again for a good period of time now.
I assume that the spike you describe is coolant temp? Why is it getting so high? If coolant is 260, then oil must be getting over 300. Neither is very good to your rings. Anyway, have you tried copper spray on the cometics? I use it &, knock on wood, haven't had leaks. Although, I monitor both coolant & oil temps closely & have an oil cooler.
#7
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I assume that the spike you describe is coolant temp? Why is it getting so high? If coolant is 260, then oil must be getting over 300. Neither is very good to your rings. Anyway, have you tried copper spray on the cometics? I use it &, knock on wood, haven't had leaks. Although, I monitor both coolant & oil temps closely & have an oil cooler.
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#9
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glad my cometics .040s are holding up...i had my heads milled too so that might help with a fresh flat surface...
as for flycutting i have seen up to .120 cuts and a 150 shot....most recommend around .080...i personally cut mine .110...
let me know if you want to try out the lindy tool, i have rented it out in the past...
as for flycutting i have seen up to .120 cuts and a 150 shot....most recommend around .080...i personally cut mine .110...
let me know if you want to try out the lindy tool, i have rented it out in the past...
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#10
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Yea we used Copper spray on both sides. ARP bolts were used and the heads were new out of the box. Will be interesting to see where exactly the leakage is. One side worked... other side didn't. Actually both did for a while but then this side showed it's ugly head.
#11
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I didn't use any spray on mine actaully says right on the cometic package not to use any...
#13
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Ah, OK, I understand.
They should not leak since you used copper spray. Did you re-torque the bolts after a couple hundred miles? Maybe there was a kink in a gasket or a ding in the block surface?
BTW, I've looked @ the seal that spray provides when pulling my heads. It heats up & flows into even the smallest defect. So, when using enough copper spray, it should seal. Maybe a litter thicker spray coating can be used on your re-install; just a thought.
#14
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Ah, OK, I understand.
They should not leak since you used copper spray. Did you re-torque the bolts after a couple hundred miles? Maybe there was a kink in a gasket or a ding in the block surface?
BTW, I've looked @ the seal that spray provides when pulling my heads. It heats up & flows into even the smallest defect. So, when using enough copper spray, it should seal. Maybe a litter thicker spray coating can be used on your re-install; just a thought.
They should not leak since you used copper spray. Did you re-torque the bolts after a couple hundred miles? Maybe there was a kink in a gasket or a ding in the block surface?
BTW, I've looked @ the seal that spray provides when pulling my heads. It heats up & flows into even the smallest defect. So, when using enough copper spray, it should seal. Maybe a litter thicker spray coating can be used on your re-install; just a thought.
#15
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GM's are fine. Was just talking about what you have now. You don't have to spray the GM gaskets. They have a coating that flakes onto the heads & block, but, I would anyway. Guess I've got a copper habit.
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I used GM MLS gaskets on my LS2 no copper spray and they are fine. I'd think about having 2 thousandths milled off the head to provide a fresh flat surface for the gaskets. As for the flycutting the stock piston crown is around 220 thousandths thick. I have flycut .080 on my LS1 and currently have .060 on my LS2 (intake side only) both motors never saw nitrous and were spun to 7200.
#20
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I'm glad to find this thread, as I'm preparing to assemble my LQ4 with 243 heads. I'm not the least interested in anything other than 100% reliablilty. As abi asked, are there an .040 gaskets with a proven reputation?