Is this too much compression for 93 octane?
Thread Starter
Joined: Nov 2001
Posts: 7,303
Likes: 4
From: Delray Beach, Fl.
Dart 205's milled to 59CC,.040 Cometics,stock 346 shortblock = over 12.1CR?
Would u leave the heads alone and just run the 62CC with the .040 Cometics for 11.3CR?
Even with a small cam would the LSX intake help me?
Cam is 214-222-566-569 115+4...
Running threw shorties and HF cats (Thats why the big split)
Would u leave the heads alone and just run the 62CC with the .040 Cometics for 11.3CR?
Even with a small cam would the LSX intake help me?
Cam is 214-222-566-569 115+4...
Running threw shorties and HF cats (Thats why the big split)
I think you definitely do not want to go 12:1 SCR and check your DCR - it's going to create more problems than you want with 93 octane.
I would say the LSX intake will be marginal but the head and port velocity/runner length guys will need to chime in.
I would say the LSX intake will be marginal but the head and port velocity/runner length guys will need to chime in.
Originally Posted by JS
Dart 205's milled to 59CC,.040 Cometics,stock 346 shortblock = over 12.1CR?
Would u leave the heads alone and just run the 62CC with the .040 Cometics for 11.3CR?
Even with a small cam would the LSX intake help me?
Cam is 214-222-566-569 115+4...
Running threw shorties and HF cats (Thats why the big split)
Would u leave the heads alone and just run the 62CC with the .040 Cometics for 11.3CR?
Even with a small cam would the LSX intake help me?
Cam is 214-222-566-569 115+4...
Running threw shorties and HF cats (Thats why the big split)
I get 11.32:1 SCR for 62cc heads and .040 gaskets
And to the question of which one to use, it depends on the camshaft specs and what DCR you end up with.
Hammer
Yeah, what he said. I don't get 12.0:1. It's lower...closer to 11.7ish:1. Remember when calculating DCR that even XE-R lobes rarely get close to a 49 degree ramp rate. They're more like 50 or 51. This will make actual measured DCR lower than the "calculated" DCR.
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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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.

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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.






