Max CR on 93 pump gas with Dart 225 and T-Rex?
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My set-up in the works;
Dart 225 milled to 58cc chamber, 2.050/1.60
Cometics .040 gaskets
2cc flycut stock pistons that are .008 out of hole
My T-Rex spec are;
243.2/249.3
609/613
LSA 109.3
Valve Timing @ .050
OPEN CLOSE
INT: 14.1 BTDC 49.1 ABDC
EXH: 55.5 BBDC 13.7 ATDC
What would be the max compression that I could safely run on 93 pump gas with this set-up?
I calculate the static compression to be 11.2, does that sound right?
How do I calculate DCR for this set-up?
Bob
Dart 225 milled to 58cc chamber, 2.050/1.60
Cometics .040 gaskets
2cc flycut stock pistons that are .008 out of hole
My T-Rex spec are;
243.2/249.3
609/613
LSA 109.3
Valve Timing @ .050
OPEN CLOSE
INT: 14.1 BTDC 49.1 ABDC
EXH: 55.5 BBDC 13.7 ATDC
What would be the max compression that I could safely run on 93 pump gas with this set-up?
I calculate the static compression to be 11.2, does that sound right?
How do I calculate DCR for this set-up?
Bob
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Originally Posted by TAF Motorsports
need the .006 specs
Valve Timing @ .006
OPEN CLOSE
INT: 37.8 BTDC 74.8 ABDC
EXH: 79.0 BBDC 40.7 ATDC
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Using J-Rod's calculator, your SCR with 2cc valve reliefs is 11.45:1
Your DCR is 8.43:1.
In my experience, 8.5 DCR is about as high as you want a pump gas motor although with your .032 quench, you can probably get away with a bit more compression (maybe up to 8.7 DCR).
To get the numbers at .006, I just added 49 degrees to the duration at .050" since these are XE-R lobes. This should get you very close.
Your DCR is 8.43:1.
In my experience, 8.5 DCR is about as high as you want a pump gas motor although with your .032 quench, you can probably get away with a bit more compression (maybe up to 8.7 DCR).
To get the numbers at .006, I just added 49 degrees to the duration at .050" since these are XE-R lobes. This should get you very close.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX tuning in person or via email press here.
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Originally Posted by Patrick G
Using J-Rod's calculator, your SCR with 2cc valve reliefs is 11.45:1
Your DCR is 8.43:1.
In my experience, 8.5 DCR is about as high as you want a pump gas motor although with your .032 quench, you can probably get away with a bit more compression (maybe up to 8.7 DCR).
To get the numbers at .006, I just added 49 degrees to the duration at .050" since these are XE-R lobes. This should get you very close.
Your DCR is 8.43:1.
In my experience, 8.5 DCR is about as high as you want a pump gas motor although with your .032 quench, you can probably get away with a bit more compression (maybe up to 8.7 DCR).
To get the numbers at .006, I just added 49 degrees to the duration at .050" since these are XE-R lobes. This should get you very close.
Looks like it is in the ball park and close to the high side.
DO you have a link to J-Rod's calculator
Thanks Bob
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OK, I found J-Rods Calculator and info.
https://ls1tech.com/forums/advanced-engineering-tech/102153-math-figure-out-if-your-car-will-run-pump-gas.html
Awesome reading and info
Anyway, I came up with 8.50059 DCA for my new set-up.
Thanks Bob
https://ls1tech.com/forums/advanced-engineering-tech/102153-math-figure-out-if-your-car-will-run-pump-gas.html
Awesome reading and info
Anyway, I came up with 8.50059 DCA for my new set-up.
Thanks Bob