Much discussion has been made on here about Alky to Gas and or Gas to Alky on larger cubic inch motors. I am, and always will be, a huge fan of Alky injection. I have ran both flying toilets and terminators on several different size engines. James Monroe has offered technical advice and guidance as well as friendship in my journey with injection. My first experience with an alky carb was in a small block 34 Chevy Roadster that I owned and my wife and son drove at the time. It had a Rupert carb on it and would print tickets. When I purchased my current dragster in 2010 it had an APD Alky dominator on it and I upgraded the engine with head hunter heads and brodix intake on the 632. With alky carb it ran a best 0f 4.63 at the Division 2 Race of Champions which was held at the Gator Nationals that year. It ran a best of 4.65 at my home track (Silver Dollar). I then switched to injection with a Terminator. My best ET with injection was 4.569 at 150 at Silver Dollar. Now with the backstory out of the way I switched to an APD gas carb. Speaking to Scott Duggins at PAR, calling Pro Systems, and APD all 3 told me that I could run faster and just as consistent on gas. I was not a believer and stated so here on the fourm but was willing to give it a try. With my first runs this past weekend at the SFG Promotions race (didn't have much luck) at Silver Dollar I have the results. My best run was Thursday at 55 degrees at about 500 feet of air, I went 4.535 at 150, I later went 4.544 at 151.26 for my highest mile per hour. It printed tickets when others seemed to struggle. I purchased the APD Carb through Scott Duggins at PAR, I put a fresh motor in and fresh transmission from Sid Neal at Neal transmissions. All I did was bolt the carb on and set the idle, didn't change anything out of the box and set the timing at 35 degrees. Don't know if there's anything left in it or not but wanted to share my results

No surprise and I told you quicker, faster and just as consistent.

Coolroy,

Please update this thread after August. By then you will have ran the gas carb in some bad air conditions.

Scott

Hmmm, "Fresh engine, 500' air"............

not trying to start an argument,but gas and alky are not far apart in cool air.august is when the difference comes into play

^^^^yup^^^^

I will update in the hot months. I am sure I will loose big when the heat and humidity are high here in Georgia.

You will lose a tenth but it will still be consistent.

My father owns the car/motor this thread is in regards to.

I will say that James Monroe is an awesome person for anyone that wants to run injection. James will always look out for you and is always available to answer questions.

The best part about the experience is that PAR and APD nailed the carb on arrival. The carb was bolted on and nothing was adjusted but the idle

An example given on Saturdays race with 330 foot times with a total spread in 8 hours of racing at the SFG race

2.935
2.935
2.942

The car just needs a driver

but overall very pleased with the service and getting a carb that was absolutely spot on at bolt on.

We will see how it runs come the august heat

My 632 with HH heads also was a few numbers better and just as consistent. Both carbs were from APD.

what does it weigh ?

Tracy, Dennis Deal and I weighed it a while back when we were making some adjustments. I can’t remember what the exact numbers are. I want to say 1965 with me in it when I ran it across the scales at the dollar but I’m not sure

sounds like it runs pretty well on either !

how was gas in the nasty summer air for you?

I have now tried two completely different gas carbs on my 632. One was in pretty bad air, other was comfortable air. Didn't really see a difference between alky or either gas carb.

coolroy, What gasoline were you using? $$$$$$

This comes up every now and then. I wonder why the difference? Other forms of racing run alcohol with very good results so I tend to think it is a cam issue or something? I think Indy cars used to run alcohol and they were getting huge horsepower per cubic inch. Not sure what Formula one racing runs. But I think that more hp per cubic inch is possible with alcohol and right combination.

I was thinking about switching from a gas carb to an alcohol carb thinking it would be more consistent, run cooler and not vary as much. I started calling around and lots of people wanted to sell me a carb except for ADP and Book. I told Bob want I wanted to do and the first thing out of his mouth was, Sure I’ll build you a carb but you will probably slow down and went on to explain to me that all the talk about bolting on an alcohol carb and picking up 2 tents was from a really bad gas combo to start with. So I have stuck with my Gary Williams gas carb and worked on the rest of the combo and it is printing slips and is very predictable. Gas works for me.

quote:

Originally posted by Quick Dawg:
I was thinking about switching from a gas carb to an alcohol carb thinking it would be more consistent, run cooler and not vary as much. I started calling around and lots of people wanted to sell me a carb except for ADP and Book. I told Bob want I wanted to do and the first thing out of his mouth was, Sure I’ll build you a carb but you will probably slow down and went on to explain to me that all the talk about bolting on an alcohol carb and picking up 2 tents was from a really bad gas combo to start with. So I have stuck with my Gary Williams gas carb and worked on the rest of the combo and it is printing slips and is very predictable. Gas works for me.

I don't like paying for the gas lol. Plus alky makes it so much easier to double enter whenever you want. Its a lot easier for the alternator/battery too bc there's less pump/fan time between passes. I only use the fan when I'm doubled, or round robin and that's just when the car is running.

F1 runs gas now from what I understand. they are limited to how much they can carry by the rules and that pretty much wiped out using alcohol.

As to a carb or injection, I'll go with how it was explained to me: On larger CI engines, using an alky carb is NOT the way to do. The issue is that as fuel demands increase, the carb's ability to flow enough fuel to feed the engine becomes a problem. You can only make the passages so large. Having a carb that can meet the airflow and fuel flow requirements of a larger engine reach a point of diminishing returns. Injection doesn't have that issue, so it's a better choice in that regard. Don't kill me on this, just going with what I was told.....

As to gas performing better than alky or vice versa, I'll throw in what I've researched so far: From what I can tell, and I might be totally wrong here, one of the biggest issues is that builders have spent considerable time and effort doing combos that are optimized on gas. I haven't found one example yet of a typical bracket racing engine that was developed specifically for alcohol. So when you hear builders say gas will make more power on a more refined combo than alcohol, that's because they tailored the engine for gas.... What I'd like to see is someone build an engine specifically for alcohol use. I'd be willing to bet that the cylinder head would be different, intake would be different, and camshaft would be different. Since alcohol is a very different fuel than gas, it's going to have it's peticulars that need to be allowed for. I'd also be willing to bet that the alcohol fed engine, if optimized for alcohol, will make more power than the gas engine due to the characteristics of the fuel.

Now I know people are going to say if alcohol was so great then Pro Stock and others would be running it, and that they are running gas for a reason.....Well, one reason is rules. NHRA specs what fuel they can run. How many teams would switch to Q16 if the rules allowed it, and why? What if NHRA said they could run any fuel they wanted? What would they run then? The other reason is because all of the stupid amounts of money they have in the development of those engines has all been around gasoline. What if they had spent that money in developing an alcohol specific engine?

If gasoline was the best fuel for drag racing, they why is alcohol the overwhelming choice for supercharged combos? If gas was so much better, I think it would be called "Top Gasoline" instead of "Top Alcohol"........

Just some thoughts going through my head....Don't beat me up too bad.....Had a hard enough weekend as it is....

Colorado, some very good points and I agree with you on most. I think if Pro Stock was allowed to run alcohol very soon they would get the tune up that would be faster than gas. But the rule is they must run spec GAS.

I also agree that on a really high performance large cubic inch motor it is more than just bolting on a carb.

Do you know what I liked about the Pro Stock Trucks they had for a while? That they used SMALL blocks and in just the few years it was around the heads and blocks for Small blocks was improved greatly. The teams put money and research into it and it showed with huge performance gains.

If Pro Stock was allowed to run alcohol I think very quickly someone would find the right combination to make it work better than gas. I think alcohol is a better fuel if anyone can find the right tune up, cams, heads or what ever it takes. The BTU per pound of fuel is lower with alcohol but since it uses much more fuel the overall gain should be significant. If we can find a way to use it.