sschoeffler
03-16-2009, 02:20 AM
Well exactly how high can I go with the stock computer on a 408 stroker?
Generation IV Internal Engine - Can I run 11:1 on 91 octane?
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Ryne @ CMS
03-16-2009, 02:42 AM
Well exactly how high can I go with the stock computer on a 408 stroker?
i have run as high as 12:1+ compression on 91 octane, but it depends on alt of different variables, like dynamic compression (cam choice), and of course tune. but 11.1 is a nice safe number for street car running 91 octane
i have run as high as 12:1+ compression on 91 octane, but it depends on alt of different variables, like dynamic compression (cam choice), and of course tune. but 11.1 is a nice safe number for street car running 91 octane
SweetS10V8
03-16-2009, 06:53 AM
Sure it will run, will it be optimal? No....
You'll have to be conservative on timing.
You'll have to be conservative on timing.
Ragtop 99
03-16-2009, 04:03 PM
Sure it will run, will it be optimal? No....
You'll have to be conservative on timing.
Ryne is correct. There's not enough data to say that it will be suboptimal. He hasn't specified the heads or cam that is being used. I'd go for it.
You'll have to be conservative on timing.
Ryne is correct. There's not enough data to say that it will be suboptimal. He hasn't specified the heads or cam that is being used. I'd go for it.
Sammyboy
03-16-2009, 04:21 PM
I think there is a general rule of 11.5:1 ....will be safe for pump gas
CodeRed2000SS
03-19-2009, 08:05 AM
I think there is a general rule of 11.5:1 ....will be safe for pump gas
thats what i go by. you will be fine with 11.1
thats what i go by. you will be fine with 11.1
RoDan
03-19-2009, 02:54 PM
I run 12:1 on 93 if that gives you an idea.
383lt1impala
03-19-2009, 05:49 PM
That's the compression the ls7 has and it runs on 91 with no problem in cali.
NemeSS
03-19-2009, 06:19 PM
I run 12:1 on 93 if that gives you an idea.
what cam specs?
what is your dcr with your cam?
what cam specs?
what is your dcr with your cam?
quintenk
03-19-2009, 06:22 PM
11:1 is stock on an ls2 I wouldn't worry at all. I'm at like 12.3 and have no problem running it on 91. Just cam it accordingly
LSGunZ28
03-21-2009, 12:35 AM
Whoever said, You should be fine needs to reword what they said..
He should Generally be fine, but the most important things id say is the DCR and how much timing its gonna be running..
He should Generally be fine, but the most important things id say is the DCR and how much timing its gonna be running..
67Ranger
03-21-2009, 02:34 AM
As long as its tuned by someone who knows what they are doing, it will run fine. We put right around 11.5:1 in all of our street car motors, and it always works great. There are other factors like cam, heads, intake, etc, but 11:1 is fine for basically anything.
Gregory
03-21-2009, 03:12 AM
I am running 12.5:1 static compression, 8.67:1 dynamic compression, 30+ degrees of timing, 93 octane or E85, 1 degree of knock reduction maximum with both.
You can do it!
I believe the LS7 has 11.0:1 static compression and must make due on 91 octane.
You can do it!
I believe the LS7 has 11.0:1 static compression and must make due on 91 octane.
Gen414
03-21-2009, 08:46 AM
Yeah, anything under 12:1 with teh right tune will be ok. I am running 12:1 in my setup, and plan on putting pump gas through it. No corn, just good old 93.
At the same time, you get a bad batch of fuel, or agressive with teh timing/tune....gotta pay attention. I personally think that @ 11:1, you can just about get away with anything....bad gas, agressive tune, and have no worries. Once you start getting closer to 11.5:1 and up, is when things start getting more critical.
At the same time, you get a bad batch of fuel, or agressive with teh timing/tune....gotta pay attention. I personally think that @ 11:1, you can just about get away with anything....bad gas, agressive tune, and have no worries. Once you start getting closer to 11.5:1 and up, is when things start getting more critical.