How to get an LS3 to 13:1 compression cheaply
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I've got an L92 to LS3 conversion I'm doing. It will be an E85 street car going in a C5. Thinking I'd want 13:1 to 13.5:1 compression. This will be my first LS build, so no experience; meaning don't assume I know my as* from a hole in the wall. Mainly doing it as just a fun project.
Is there an inexpensive way to get there? Custom pistons my only option?
I'm interested in cheap, because if it gets too expensive, I figure I'll just bite the bullet and go with an ERL dry sleeve 440ci.
Is there an inexpensive way to get there? Custom pistons my only option?
I'm interested in cheap, because if it gets too expensive, I figure I'll just bite the bullet and go with an ERL dry sleeve 440ci.
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OK, I have used RaceTec pistons @ 16:1 for "drift" cars.
To supply the 13:1 - X:X is no problem for my service.
A note, you should be careful of pump E-85.
The camshaft should be specified with WIDE L/C's, good for the Hendrick head you have stated.
Will you keep the L-92 VVT ?
Lance
To supply the 13:1 - X:X is no problem for my service.
A note, you should be careful of pump E-85.
The camshaft should be specified with WIDE L/C's, good for the Hendrick head you have stated.
Will you keep the L-92 VVT ?
Lance
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Why wouldn't you want that much compression, my street car is 13.7:1. My only regret is not going closer to 14.5:1. Good batt and starter are a must though haha.
You could weld the chambers and angle mill the heads. With the stock bottom end it will be tough to get a real cam in it though with out cutting valve pockets in the pistons.
You could weld the chambers and angle mill the heads. With the stock bottom end it will be tough to get a real cam in it though with out cutting valve pockets in the pistons.
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I ran a l92 with ls3 heads milled to get the compression to 11.1. I then ran a off the shelf comp lsr281 with full valetrain upgrade, Victor Jr intake with a aed 850 carb backed by a 4l80e with a 3200 converter, and 12 bolt with 4.11s. This was in a 3000lb 68 camaro and ran 10.80s driven to the track and back on 93 premium.
Not sure how fast your wanting to go but that type of compression for what it seems like your doing (street toy) I don't think you would need that much compression. To each their own just thought I'd share my experience with a pretty similar setup.
Not sure how fast your wanting to go but that type of compression for what it seems like your doing (street toy) I don't think you would need that much compression. To each their own just thought I'd share my experience with a pretty similar setup.
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I did this you want to do and is very simple I'm using a solid roller on e85 stock block rods pistons crank save for fly cutting the pistons .125
I flat milled the Trick flow 255cc GenX heads .150 new off the box had Patrick G spec a cam.
Still on ls3 intake manifold and throttle body my ls3 runs consistent 10.5 the first time to the track with only a 3,400 stall.
Combustion chambers are @ 45 cc compression 14.1 to one using Power Master 9509 starter with a 17lbs Braille battery.
OP here's a Christmas present for you enjoy it.
http://www.corvetteforum.com/forums/...track-day.html
Merry Christmas every one!
I flat milled the Trick flow 255cc GenX heads .150 new off the box had Patrick G spec a cam.
Still on ls3 intake manifold and throttle body my ls3 runs consistent 10.5 the first time to the track with only a 3,400 stall.
Combustion chambers are @ 45 cc compression 14.1 to one using Power Master 9509 starter with a 17lbs Braille battery.
OP here's a Christmas present for you enjoy it.
http://www.corvetteforum.com/forums/...track-day.html
Merry Christmas every one!
Last edited by CAMSTER; 12-23-2016 at 11:58 AM.
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Yes, I agree AND would like to add a comment.
The L-92, LS-3, LS-7, 2006+ year LS engine uses my 60-2 (58x) TW.
THAT VERY ART allows for a static C.R. increase of .5 due to a more accurate Spark Instant.
Thus, that too would be a safety factor, yours as fitted by the OEM.
Lance
The L-92, LS-3, LS-7, 2006+ year LS engine uses my 60-2 (58x) TW.
THAT VERY ART allows for a static C.R. increase of .5 due to a more accurate Spark Instant.
Thus, that too would be a safety factor, yours as fitted by the OEM.
Lance
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Go as high as you can. This is my 15.0:1 alloy 6.0 with ls3 heads we dynoed the other day. 721hp @8000rpm, shoukd be more but vac pump wasnt working
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Nice thanks for sharing do you do any street driving with it? and what transmission behind it.
You where the motivator for me going to the machine shop to have .050 removed from my heads then went back and asked for another .050 about 3 days later return with the heads for another .050 they thought I was kidding I said no go for it by then we were like 5 thous from the accessory bolts holes threads but made it all work glad you inspired me thanks.
You where the motivator for me going to the machine shop to have .050 removed from my heads then went back and asked for another .050 about 3 days later return with the heads for another .050 they thought I was kidding I said no go for it by then we were like 5 thous from the accessory bolts holes threads but made it all work glad you inspired me thanks.
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How much slippage would you see with a stall that tall do you know anybody using it on the street? I would love to have a hard hit 4000 and thinking too much in terms of slippage and traction requirements.