Highest "safe" DCR for 92 octane?
05-08-2007, 05:49 PM
#1
Staging Lane
Thread Starter
iTrader: (2)
Join Date: Jul 2006
Location: Waukee, Iowa
Posts: 83
Likes: 0
Received 0 Likes
on
0 Posts
Highest "safe" DCR for 92 octane? Hello guys.
I'm looking at a set of heads, and wondering if they'll be safe to use with my current setup on 92 octane gas, which is basically all I can get around here.
Using JROD's excellent calculator, I show SCR at 11.35 and DCR at 8.75. What do you guys think, is this too much DCR for 92 octane gas? Anyone with personal experience with similar numbers?
Thanks in advance...
P.S. This is on a car with bolt ons, 228/232 on 114+4 XeR lobe cam, and heads "would be" 59cc Patriot LS6 Stage IIs. Thanks!
I'm looking at a set of heads, and wondering if they'll be safe to use with my current setup on 92 octane gas, which is basically all I can get around here.
Using JROD's excellent calculator, I show SCR at 11.35 and DCR at 8.75. What do you guys think, is this too much DCR for 92 octane gas? Anyone with personal experience with similar numbers?
Thanks in advance...
P.S. This is on a car with bolt ons, 228/232 on 114+4 XeR lobe cam, and heads "would be" 59cc Patriot LS6 Stage IIs. Thanks!
Last edited by Higgs; 05-08-2007 at 06:05 PM.
05-08-2007, 09:17 PM
#2
Do you have a good cold air system? How tight is your quench? The tighter the better. Does you car normally run cool or does it run over 200 degrees? The list could go on but you get the drift.
05-08-2007, 10:12 PM
#3
Staging Lane
Thread Starter
iTrader: (2)
Join Date: Jul 2006
Location: Waukee, Iowa
Posts: 83
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by 1989GTA
Do you have a good cold air system? How tight is your quench? The tighter the better. Does you car normally run cool or does it run over 200 degrees? The list could go on but you get the drift.
05-09-2007, 08:27 AM
#4
Moved from advanced tech.
__________________
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.
05-09-2007, 10:32 AM
#5
I think you would be safer w/ a DCR closer to 8.5. If you would be willing to run cometic gaskets you can go w/ an 0.040 thickness and run 64cc chambers. This puts the DCR at about 8.52 w/ a quench of 0.033. It is important to tighten up the quench distance to resist detonation. If you are gonna stick w/ the GM MLS gaskets I would go w/ a 62cc chamber, which puts DCR at 8.43. Of course I do tend to lean toward the safe side.
05-09-2007, 05:11 PM
#7
He was origionally leaning towards a 62cc heads, but they were sold before he bought them. Also looking at a set of used 59cc, but I recomend against it due to the DCR. As you suggested if he was buying new a set af 64cc heads with the .040" Cometics would be the best setup. I was leaning towards the 8.4-8.5 DCR range, but nothing is set in stone and I could be leaning a little on the low side for safety.
Originally Posted by 5.3LJimmy
I think you would be safer w/ a DCR closer to 8.5. If you would be willing to run cometic gaskets you can go w/ an 0.040 thickness and run 64cc chambers. This puts the DCR at about 8.52 w/ a quench of 0.033. It is important to tighten up the quench distance to resist detonation. If you are gonna stick w/ the GM MLS gaskets I would go w/ a 62cc chamber, which puts DCR at 8.43. Of course I do tend to lean toward the safe side.
Trending Topics
05-09-2007, 06:46 PM
#8
11.35?? with only 92.. hmm.. pushing it.. but shouldnt be too bad..
why dont gas stations carry 93 anymore? Even the sticker on the gas door to my Typhoon says to use 93... i can only get 91.. and it seems to not like certain 91's too. sorry that was off topic
why dont gas stations carry 93 anymore? Even the sticker on the gas door to my Typhoon says to use 93... i can only get 91.. and it seems to not like certain 91's too. sorry that was off topic
05-09-2007, 07:32 PM
#9
Registered User
iTrader: (15)
Join Date: Aug 2005
Location: BTR, La
Posts: 1,363
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by GR33N GoblinM6
11.35?? with only 92.. hmm.. pushing it.. but shouldnt be too bad..
why dont gas stations carry 93 anymore? Even the sticker on the gas door to my Typhoon says to use 93... i can only get 91.. and it seems to not like certain 91's too. sorry that was off topic
why dont gas stations carry 93 anymore? Even the sticker on the gas door to my Typhoon says to use 93... i can only get 91.. and it seems to not like certain 91's too. sorry that was off topic
Ben T.
