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LS7 heads or ls3 heads

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Old 03-09-2019, 09:39 PM
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Just wish the stock castings had a little better valve angle
Old 03-24-2019, 02:07 AM
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Originally Posted by Che70velle


Next time, instead of cutting valves, check out Moroso 37900 offset dowels for big block Chevy. They are same size (.646”) as LS and move the head .030”
I use them on my 6liter builds with 823 heads to give me more room on intake side, for unshrouding. For what you did, these would work great for LS7 heads, which as you said, push the exhaust valve way over and shroud it. No intake alignment issues. Pretty trick.
On an lq4 with 823 heads, would the dowels cause zero issues or does something additional have to be modified?
Old 03-24-2019, 11:14 AM
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Read the quote in your post. He says "..my 6 liter builds with 823 heads" . LQ4 IS a 6 liter engine, and you DO have 823 heads. How is your engine different than what he describes?
Old 03-24-2019, 01:34 PM
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It doesn't matter which heads are used. Who does the induction work does. Seen cathedral ports, Ls3 and 7 heads do 800+ with lq4's around 8k under 420 ci.
Old 03-24-2019, 02:08 PM
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For Ls7 heads to fit a smaller bore
1 moving dowels around
2 smaller exhaust valve
Rather deal or work with exhaust as not 2 hamper the intake side with moving the heads towards the intake side to help with exhaust valve clearance with moving dowels.
Old 03-24-2019, 02:50 PM
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Exhaust flow is very different bs intake flow imo. When you first open the exhaust valve you have 1000 psi cylinder pressure. It will vent down fine even if shrouded or less than optimal. Then on exhaust stroke, positive displacement will force air out.

Intake side especially NA has far less pressure to move it. So yeah, make sure your intake valve can flow first and foremost.
Old 03-24-2019, 04:18 PM
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Darth did you get the text sent? Want to hear what was said. If we can get this did and it helps there's nothing left to imagine. If not a arm in cost, should be though. Found a way around Ti valves and C5r heads and Mozez style heads. Hollow stem 6.3 valves and changing guides. Little smaller than typical ls diameter valves. Just a thought for future reference. Talked with the head instructor for a welding school here. Free welding, cost are only for material.
Hmmmmmmmm?

Last edited by Smokey B; 03-24-2019 at 04:25 PM.
Old 03-24-2019, 04:23 PM
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Originally Posted by foxsl
On an lq4 with 823 heads, would the dowels cause zero issues or does something additional have to be modified?
No issues. Intake fitment is good. 4 corner steam port lines work fine. The most recent LQ4 with 823 (GMPP CNC ported) heads, I went with 11/32 pushrods and they didn’t need any work to use. It’s a straight forward procedure that requires no work.
I would however recommend to you and everyone else planning to use the dowels, to always mock up your setup to make sure, before final assembly. I’ve found no problems with any setup, so far, using the dowels.
Old 03-24-2019, 04:37 PM
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Originally Posted by Smokey B
Darth did you get the text sent? Want to hear what was said. If we can get this did and it helps there's nothing left to imagine. If not a arm in cost, should be though. Found a way around Ti valves and C5r heads and Mozez style heads. Hollow stem 6.3 valves and changing guides. Little smaller than typical ls diameter valves. Just a thought for future reference. Talked with the head instructor for a welding school here. Free welding, cost are only for material.
Hmmmmmmmm?
I actually called several times left messages. Oh well...
Old 03-24-2019, 05:01 PM
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Very busy found texting better. Got 1 back after 12 am. Race season has started again. Use me as a reference with 1 of a kind Ls7 heads. LOL!


Luv the base of these intakes.
https://www.yellowbullet.com/forum/s...d.php?t=533337
https://www.yellowbullet.com/forum/showthread.php?t=1156026&page=122
Holley with shorter runners post #45 2nd picture? Hmmmmmmm. Price of material, funny.
https://www.yellowbullet.com/forum/showthread.php?t=1128010&page=3

Last edited by Smokey B; 03-24-2019 at 05:13 PM.
Old 03-24-2019, 06:31 PM
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Originally Posted by G Atsma
Read the quote in your post. He says "..my 6 liter builds with 823 heads" . LQ4 IS a 6 liter engine, and you DO have 823 heads. How is your engine different than what he describes?
lots of people don't mention every single aspect, and because I haven't done this yet, I'd like to know if there are any extra details not mentioned as far as other modifications you have to do...wouldn't u?
Old 03-24-2019, 06:33 PM
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Originally Posted by Che70velle


No issues. Intake fitment is good. 4 corner steam port lines work fine. The most recent LQ4 with 823 (GMPP CNC ported) heads, I went with 11/32 pushrods and they didn’t need any work to use. It’s a straight forward procedure that requires no work.
I would however recommend to you and everyone else planning to use the dowels, to always mock up your setup to make sure, before final assembly. I’ve found no problems with any setup, so far, using the dowels.
thanks a ton 👍




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