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LQ9 Block - What would you do?

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Old 06-09-2016, 08:18 PM
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Why not clean up the bore and go a little larger to a 370?
Old 06-09-2016, 09:29 PM
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What fuel do you plan to run? I am not a huge fan of the GT2-3 on anything larger then a 5.3

Also, given your planned boost and CR I would want a cam that would drop your Dynamic CR a hair and the GT2-3 isn't it. What pulley combo were you running before and what boost? What your looking to do isn't too far off from my new setup, only my head flow numbers are higher and my cam is gonna be larger however my plan is to max my 2300 and hit it with some spray. For your setup I personally would try to get your dynamic CR in the 7.8 range if you are going to be running 93 and meth. Just my opinion.

For that Static CR with those heads are your pistons out of the hole? What head gasket? With a -11 dish and a 66 chamber your pistons must be out of the hole some or your CR will be lower.
Old 06-10-2016, 06:16 AM
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Originally Posted by gamble686
Why not clean up the bore and go a little larger to a 370?
It already was a 370.
Old 06-10-2016, 06:28 AM
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All great questions, and Im trying to recall all the details: 1. it was running ~15lbs of boost and I'd overdriven the crank and underdriven the pulley to get there with 8 rib setup...cant exactly remember pulley sizes off hand, but hence the meth!
2. Plan to run 93 pump gas. I'd like to get away from meth - just dont think its needed to get to lo 600's that Im looking for - I just consider it a bandaid (my opinion)
3. I seem to recall CR was closer to 9.3 previously using Head gasket: MLS C5317-051 Cometic gasket...and I always felt that left plenty of power behind!
4. I think I have this *** backwards and should be looking to raise CR to lo 11's, but open to all suggestions?


Originally Posted by 03sierraslt
What fuel do you plan to run? I am not a huge fan of the GT2-3 on anything larger then a 5.3

Also, given your planned boost and CR I would want a cam that would drop your Dynamic CR a hair and the GT2-3 isn't it. What pulley combo were you running before and what boost? What your looking to do isn't too far off from my new setup, only my head flow numbers are higher and my cam is gonna be larger however my plan is to max my 2300 and hit it with some spray. For your setup I personally would try to get your dynamic CR in the 7.8 range if you are going to be running 93 and meth. Just my opinion.

For that Static CR with those heads are your pistons out of the hole? What head gasket? With a -11 dish and a 66 chamber your pistons must be out of the hole some or your CR will be lower.

Last edited by dhpro; 06-10-2016 at 10:00 AM.
Old 06-10-2016, 08:16 AM
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Whoa, time out. 93 Oct only, 14psi and low 11 SCR is not a good idea. I wouldnt go low 11's, low 10's will be a noticable increase.

If you want to run 15psi on 93 then plan to run meth or keep your CR low like low 9's
Old 06-10-2016, 09:38 AM
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I agree with Pat.

I like the idea of compression in the 10's, but not without meth at that boost level. Especially where the blower makes boost so instantly. 10 PSI at 3200 RPM on 93 alone and that compression is a tall order. Youre talking about pretty high cylinder pressures.
Old 06-10-2016, 09:53 AM
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Originally Posted by Vortec350ss
I agree with Pat.

I like the idea of compression in the 10's, but not without meth at that boost level. Especially where the blower makes boost so instantly. 10 PSI at 3200 RPM on 93 alone and that compression is a tall order. Youre talking about pretty high cylinder pressures.
Im not married to hi boost...Id prefer to pulley up and drop boost (and heat!) if I could find the power with compression, cam...etc. I always wanted to avoid meth/cooling the charge, and I think that these days (vs 07 when I started this) its achievable to get 600rwhp with proper 370 combination. My CTSV can do it with a pulley & cam change pretty easily.
Old 06-10-2016, 11:23 AM
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It can be done, that is correct. I think in large part that is because blower cams have come a lone way from the GT2-3 days in the LS world.
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