What is the highest CR motor for pump gas?
#1
TECH Apprentice
Thread Starter
Join Date: Dec 2001
Location: CA
Posts: 352
Likes: 0
Received 0 Likes
on
0 Posts
What is the highest CR motor for pump gas?
I am getting a 10.8 CR motor, but I want to run pump gas (in CA, it's 91 octane). I also want to be able to squeeze when I need to, is this a pipe dream? Would I be okay if I just retarded the timing? Thanks.
#3
Re: What is the highest CR motor for pump gas?
I wouldnt squeeze with 91 Octane and 10.8:1 static comp. I would run a bit of race gas at the track. You are asking to lift a head
Cheers,
Chris
Cheers,
Chris
#4
TECH Apprentice
Thread Starter
Join Date: Dec 2001
Location: CA
Posts: 352
Likes: 0
Received 0 Likes
on
0 Posts
Re: What is the highest CR motor for pump gas?
Thanks guys. So I guess I'll be okay with 91 octane for most of the time. Sounds like mixing in some 100 octane would be best for N2O. Any estimate on what octane rating I would need to reach for 10.8 CR and a healthy shot of N2O? I'm thinking that it would also depend on the size of the shot and also the timing retard, is that correct? So if I wasn't running with a higher octane gas, could I just reduce the shot? I guess I could try some experimentation and see if I pick up any knock retard.
#5
TECH Fanatic
Join Date: Nov 2001
Location: Chi-Town
Posts: 1,055
Likes: 0
Received 0 Likes
on
0 Posts
Re: What is the highest CR motor for pump gas?
on pump gas you can get away with about 11.4:1 and have some leeway.
this means premium 93-94 all the time and very careful timing curves
on the squeeze, put in some 100 unleaded
this means premium 93-94 all the time and very careful timing curves
on the squeeze, put in some 100 unleaded
#6
TECH Veteran
iTrader: (4)
Join Date: Nov 2001
Location: Simi Valley, CA
Posts: 4,712
Likes: 0
Received 0 Likes
on
0 Posts
Re: What is the highest CR motor for pump gas?
On the 91 octane you will want to run 25-26 degrees of timing with an 11:1 setup. Works ok for me. <img src="gr_images/icons/wink.gif" border="0">