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Cal-look/High Performance => Pure racing => Topic started by: Chuck Fryer on February 25, 2011, 23:31:01 pm



Title: Comp ratio vs horsepower
Post by: Chuck Fryer on February 25, 2011, 23:31:01 pm
I keep debating myself on what to do here. Pump gas or race gas. 10:1 and I am fine on pump, 11:1 and I need 110 octane. I am putting together a 2332 wedgeport engine with a CB 2296 cam ( .593 lift, 280@.050). I owned an identical engine a few years ago and was very pleased with it, it ran 11.80's and was still street driven. Granted, it was no long distant machine, 4.12 r/p and a 1.14 4th really cuts into your distance.

The question is, how much hp is lost dropping from 11:1 down to 10:1? Then, if I choose to go race fuel, why not make it 12:1? Cause if you gotta run race fuel, might as well make it worth your while, right?

I found a generic site that estimated my hp loss to around 5 hp with a drop down to 10:1, and a gain similar with a bump. Which seems to make a 1/10th change et wise, does this sound correct?
 
I'm open to any and all input


Title: Re: Comp ratio vs horsepower
Post by: TexasTom on February 26, 2011, 01:30:18 am
Chuck, What is the intended use of the car?

If it's street driven, then go pump gas.
If it's track ONLY, RACE!

I've tried in the past to live on the edge/line that divides the two, but realized I'd like to DRIVE IT, so made the necessary adjustments to not have to worry when I fill up. Nothing worse than limiting your options ... can't go, it's too far, it'll overheat ...

Then again, if it's track ONLY, why not 13.5:1 ... that WILL make a difference. ;)


Title: Re: Comp ratio vs horsepower
Post by: dragvw2180 on February 26, 2011, 03:43:32 am
 Thats why I went turbo, 8.2 compression, runs cool . 


Title: Re: Comp ratio vs horsepower
Post by: TexasTom on February 26, 2011, 04:21:11 am
Thats why I went turbo, 8.2 compression, runs cool . 

Different strokes for different folks ... everything has it's drawbacks.


Title: Re: Comp ratio vs horsepower
Post by: The Ideaman on February 26, 2011, 04:44:17 am
Chuck, why not bump up the compression and run E85?  Runs cool and makes power.  You live in the corn belt, don't you have ready access?


Title: Re: Comp ratio vs horsepower
Post by: Chuck Fryer on February 26, 2011, 04:56:58 am
E 85 is all over here, and I had tossed that idea around for a while. The learning curve would be a bit tricky I guess, how much more fuel needs to be pushed thru compared to gas?


Title: Re: Comp ratio vs horsepower
Post by: TexasTom on February 26, 2011, 06:10:22 am
Chuck, why not bump up the compression and run E85?  Runs cool and makes power.  You live in the corn belt, don't you have ready access?

That's a great idea, IdeaMan!


Title: Re: Comp ratio vs horsepower
Post by: Bruce on February 26, 2011, 07:47:19 am
Build it for pump gas, then take 50 lbs out of the car.  Then it'll be just as fast as with the compression motor.


Title: Re: Comp ratio vs horsepower
Post by: Mike Lawless on February 26, 2011, 18:02:20 pm
Chuck, with E85, your AFR needs to be in the 9-1 range (as compared to 13-1 with gasoline). With IDAs you'd need sufficient fuel flow at high rpm to support it, so depending on how your system is set up now, would determine how much work it would take to make it work.  Just as a "guesstimation", your fuel pump would need to flow MINIMUM 1.5lbs per horsepower/Hour. More to be safe. But with all that set up, it would run way cooler, and you could run the compression up around 12-1.

Some don't think it's worth the hassle. I look at it this way. The price of fuel would be around 3 bucks a gallon (over $12 and rising for race gas now). You could "hot lap" the car at the races. You can drive it around on the hottest days without burning it down.

I've been on methanol for a few years now and will never go back to gasoline. Not on IDAs though.


Title: Re: Comp ratio vs horsepower
Post by: Chuck Fryer on February 26, 2011, 18:32:00 pm
The good thing is, I have no fuel system yet! The car is still being put together. I planned on a typical Holley blue pump, and I already ran a 3/8" hard line thru the tunnel. Thanks for the info Mike, I'm going to do some more research and consider this option.


Title: Re: Comp ratio vs horsepower
Post by: Chuck Fryer on February 28, 2011, 22:51:01 pm
So far, a holley black pump is recomended, and a rough est of vent x5 for jets. Yep, I'm gonna give it a go!


Title: Re: Comp ratio vs horsepower
Post by: K-Roc on March 01, 2011, 03:46:41 am
E85 on EFI !

time to come on over to the Dark Side!  Once you go to EFI you will never go back to carbs.

You could even use your IDA,S as the throttle bodies if you wanted to.

I wish we had E85 up here in Canada I would run it in second.

Cheers



Title: Re: Comp ratio vs horsepower
Post by: Bruce on March 01, 2011, 06:02:02 am
I wish we had E85 up here in Canada I would run it in second.
Closest:

Ethanol (E85)
Lakewood Shell
1401 172nd St NE
Marysville WA 98271
Phone: 800-554-5549
Distance: 70 Miles
Access: Public - credit card at all times


Title: Re: Comp ratio vs horsepower
Post by: Zach Gomulka on March 01, 2011, 22:21:49 pm
You'd be lucky to make it to the station and back at that distance ;)


Title: Re: Comp ratio vs horsepower
Post by: K-Roc on March 02, 2011, 01:00:46 am
My thoughts exactly, Plus the stupid boarder Line ups..........


Title: Re: Comp ratio vs horsepower
Post by: gbaker770 on March 02, 2011, 03:16:36 am
I'll be watching your project with great interest Chuck. Good luck, I'm sure it will pay off.