After doin a little home work and talkin to some of you guys I decided to try C-12 first. I found something kinda curious to me. Unfortunaly I had a solinoid problem and wasnt able to spray on it. I have been running 110 with pretty good tuning I had 12.5 to 12.7 on the air/fuel. Switched over to the C-12 and it leaned out to 13.5 to 14. I was running 45 in the power jets. played with the needle a bit and upped the power jets a few times to get back to 12.5 12.7 The thing just came alive! Then I added a few more disc's to the ct. (tryin to do one thing at a time) which leaned me out again, so back to the carb. She just kept getting faster and faster, It has never ran that good. My question is with higher octane does the motor need more fuel? and is there hp gains to be had from just a bump in octane or paticular brand of fuel?

 

You can gain and loose power between different brands, different fuels, and different octanes. It actually sounds as if you werent on the edge of detonating, if not detonating a little. The added octane probably cooled the bugger down, and let you run it a little harder. Depending on which brand of 110 you were running, the c-12 should have slowed the burn rate down. So if you gained power from that, you either needed colder plugs, or were detonating. I dont believe there is any oxygen adders in c-12, so I cant see how it could gain you power. I dont know for sure thow.

 

C12 is 108 octane

 

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Vp110 has a MON of 107. C12 has a lower specific of gravity as well. Slower burn rate.

 

I just dont know if he was running VP 110 - its formulated differently than standard 110. So I guess we'd need to find that out to help him determine what the problem was.

I know I've run standard Sonoco 110 race fuel and found lean issues that I didnt have with C12 - So, I think there is more to it than octane. There's something in that C12 that is much more forgiving.

 

The only 110 I could get here locally is K&S 110 race fuel. Thats what ive been running. Plugs are 10's and new. I think Im totally lost now! I guess I thought that C-12 was 112 octane. So Im making more power at basically the same air/fuel (on motor) with less octane. So is this stuff going to be safe to spray on at my compression? (13:1) Im wondering why it would want more fuel with the C-12 than with the other fuel. Something other than fuel, mechanical ie carb inconsistant? I find that hard to believe because lectrons seem to hold their tuning really well.
Im not kidding guys the difference was night and day. It ran really cool for 80 degree weather and pass after pass I only heard the fan kick on once.

Marky are you running C-12? Anyone else seen this?

 

I run C12 exclusively. I used to run U4, and it ran good in the DS, but I had problems with it on the Edlebrock carb - aparently some chemicals in the fuel that caused me to rebuild by Edlebrock carb twice - Duncan, the guys that rebuild my carb, told me to never run U4 again in that carb - it was a mess! So I talked to the fuel experts at VP, and they said its possible that it could happen, and recommended that I switch from U4 to C12. All my race gas banshee head friends will run nothing but C12 - PERIOD. I dont know if you remember, but I tried to switch back to 110 when we were at the dunes in Winchester bay - remember when my EX was popping like mad with my old BD system? I wanted to get cheap, so I switch from C12 to 110 - bad idea .... I've never gone back. For me, its not mearly the quality of the fuel, its also the cooling properties of C12 - which keeps my air/oil cooled motor on nitrous running cool.

Also, since the boss is buying my fuel, it will be C12!

 

I remember that! LOL we wont go there[img]i/expressions/face-icon-small-wink.gif[/img] So aside from my main question, C-12 is going to be safe to run nitrous on at my compression? I suppose theres a ton of variables that could explain the jump in power. even the possibility that the a/f gauge was out of calibration. I thought that it was running pretty good on the other fuel. But like I said the difference was really noticable. Just trying to figure out if it was possible from just a change in fuel.

 

Keith,

Im gonna go back to my old rule of thumb, always run at least (especially at sea level) what the piston manufacturer recomends. And if you are running nitrous, run at least 3 or 4 octane points higher - that's what the BD training manual says. I hope you dont mind, but I'm not going to be the one to go out on a limb here and tell you what you need to run - because, there are places I dont want to go with the BD system! [img]i/expressions/face-icon-small-wink.gif[/img]

Marky