What do you modified guys run?

I have run MS109, but have recently rebuilt our C7, and has ability to rev up to 7500...limiter is set to 7200. Have seen a lot of guys running C12 and the like up to 7000, but what about a little higher rpm? My car for example makes 9-1100 on motor...depending on the setting.

Compression with no boost is about 9.8/1. With boost not sure, but probably upper 11's to 1, or maybe higher.

Thinking about running a mixture from now on....thoughts?

 

Any reason not E85?

I used to be all about VP C12. Then MS102.

Now E85. I just can't understand paying 10-12 / gallon for race gas when E85 is available unless you are in a sanctioned class with fuel restrictions.

 

I have thought about E85, but not real familiar with it....will ask my tuner his thoughts about it.

 

Yea, he said the C7 doesn't have near the injector size to run E85....said would not suggest it. That is coming from Patrick G who is pretty solid on LSX style tuning applications.

 

I just re-read your OP....E85 is fine NA, you are boosted. Yes, you would need to upgrade your injectors (or at least your cam lobe) for E85.

I'd go with MS103 if I were you.

 

I have upgraded the cam so that part would be no problem...still think the injector size will be an issue. It was recommended that I try Mach 110 which is a Gulf fuel, but not real familiar with it. Have always used VP fuels.

 

Is the 103 good for engines revving beyond 7000rpms?

 

Sorry, MS109. MS103 I used in my motorcycles.

 

I'd probably rather run meth injection before leaded race fuel, just because of the cost, and inconvenience.

 

these fuels are unleaded.

 

Depends on what you want from the car and what fuels you can get.

Never had an issue with MS109 and have used it in a number of forced induction builds with no issues. It is unleaded, doesn't screw with the 02's and you can run meth with it and not have problems.

You can get more out of C16 if you are fuel limited on timing now, or go to Q16 but generally you need more fuel with Q than what you do with C so it does require tuning with either of these, not only for correct A/F but also to shut the 02's off because these are both leaded fuels and will kill them over time.

If you want something closer to a street fuel there is VP100, Sunoco 100, Sunoco 104 are all popular choices and I have found some of these even at the pump. Actually one just north of us has 100 at the pump and most race tracks typically have 100 and 104 at the pump too.

Now I have never heard of a fuel being RPM limited....that is a new one to me. Each fuel is going to have it's own specific gravity, heat output, burn rates, and energy but never seen one or the other have to do with RPM. RPM is going to be a combination thing....valve train, power adder RPM range, air flow....a number of things will give you that.

Heck we could spin the World Challenge cars to 7600 on Sunoco 104......not that the fuel had anything to do with it.

 

Am I the only one who wants to hear the motor screaming at 7200? /jealous

 

Yea, all this fuel is unleaded. If you read about race fuels, they all have ratings indicating what rpm ranges they work between...didn't know that either, or why really. Based on the power this car is making, I want the right fuel in it to maximize the power output, and tuning capabilities. Can you mix C16 with say 93 pump octane?

And yes, will post up a vid soon of the car on the dyno as the limiter is set at 7400 now. Probably will reduce that a bit, but will be over 7k.

 

My fuels place is out of the MS109 now...they recommended Gulf Mach 110 as a replacement....thoughts??

 

Looks to be the same price as C16 for 7 less MO points.

C16 is what I would run if you have it available to you, and it shows the range as up to 7500rpm (for what it's worth - I've never seen how fuel RPM bands can mean a damned thing, but that's just me).

 

No E85 in my area but if so I would be using it. I run 93/meth on my normal tune and when I'm gonna be at an event or running the car even harder I switch to my Sunoco 104/meth tune. I can get the sunoco at the pump along with a few other race fuels and I like the fact it's unleaded.

 

7600 RPM shifts....on Sunuco 104.

 

Suddenly I feel the urge to increase my redline.

 

Just picked up 10 gallons of MS109 for race this weekend. When not using 91 **** pump gas I run the MS109 for events. Never let me down. Price isn't bad, and seems to work well.