Page 1 of 2

How do I use Methanol in a Drag racing application?

Posted: Mon Mar 10, 2008 1:59 am
by ninety3
Hi all. I am building a Drag car, and am considering fuel types. I will be running a carbied 308 Holden small block V8, and am wondering if using methanol or another type of alcohol based fuel is more advantageous than say Avgas or Pump fuel. The motor is stock stroke, about 10-5:1 comp, has some large head work done and a good cam (stage 4 I'm told). Also using a Torquer Manifold. As yet, I dont have a carbie in mind, but am thinking about a Holley 750 DP. I am aware that in meth applications, I will need oversized jets, due to using more fuel in comparison to peterol.

What do I need to consider when using this fuel?
What are the pros v cons for alcohol fuels?
Do I need anything special to set it up on my car?
Can NOS be used with this fuel?
When money allows, I will consider changing cams, and upping the comp ratio, as well as getting a better manifold (Victor Junior maybe?) and forged pistons.

Any other info would be much appreciated. Speed and power is what I am aiming at.

This is a TRACK ONLY car, therfore road/street legalities dont need to be considered.

Posted: Tue Mar 11, 2008 1:48 pm
by John Wallace
I personally wouldn't use a carb with alcohol.
Too much headaches to get it right.

Fuel injection with the alcohol would work good.

To modify a gas carb to work with alcohol would take more than just bigger jets. Plus I'd go with a bigger cfm carb.

Higher CR would be better also for the alcohol, but will still work.
The engine will probably run cooler and usually have more torque.

Posted: Tue Mar 11, 2008 2:04 pm
by Tod74
Ron's Terminator

Posted: Tue Mar 11, 2008 7:00 pm
by ninety3
Tod74 wrote:Ron's Terminator
Rons Terminator??


I will be running with this comp ratio and carb for a while, as thats how I bought the motor. But when money allows, I will be making mods to it. If I go injection, I'd like to have a 6/71 under it first, so cant go too crazy with comp ratio there...

Posted: Tue Mar 11, 2008 10:48 pm
by RayJE Carburetors
a "good" 750 alcohol carb will work better than piss and dribble and cheaper ... you will never have to touch the thing ... with a bypass return reg and belt driven fuel pump if u want to richen a tadd for conditional changes just up the fuel pressure... conversely to lean it ...... llower fuel pressure

alcohol is the way to go for any bracket race car.... more consistant and its cheap... you can get a 200litre of Coogee methanol for $180

dont try and run it on an electric fuel pump... that is the cause of all alcohol carb problems...... because of the larger .150 needle and seat ... a float only has enough bouyancy and leverage to close off a seat this big with around 3-4psi.....5 psi if its a brass float and the needle and seat is lapped....... if you dont run the carb sideways you will have to run a nytrophl float notched for jet ext and a nytrophyl float will hold less fuel pressure than a brass float....

Posted: Tue Mar 11, 2008 11:17 pm
by Talisman
I don't see why you would tell someone to not use a carb on meth? Seems to work great for countless racers such as myself. Called rupert, bought a carb and pump...put it on. Fired it up. Dead on. Definitely the best money i've spend on my racing operation in recent years. No reason it cna't be done..you just have to decide if its a good fit to your racing and combination. For me, heat was a big issue becuase of hotlapping at local tracks once you get down to 4th round or better, that was the biggest plus for me. Very consistent , runs cool and I don't have to pay big bucks for VP fuel anymore... Thank God.

Methanol

Posted: Wed Mar 12, 2008 1:03 am
by 340king
Methanol is a good fuel for ET bracket racing where consitency is rewarded.

That said, there are some things that need consideration. Although the fuel is cheaper, you burn quite a bit more. There is no free lunch. The fuel fittings will also need to be steel rather than aluminum since methanol is not really friendly with aluminum.

Methanol is hygroscopic (it absorbs water). If you run in a humid climate, care must be taken to keep your supply clean and pure with sealed containers. I bought all my own methanol by the barrel and kept it in a controlled environment away from moisture.

You are at the what I would consider the minimum compression ratio that methanol becomes viable. The engine may be a little jet fickle at that compression ratio. I have played with different engine combos using the same carb, ignition, etc. The lower compression engine ran way rich with the same settings that burned pistons due to a lean condition on the high compression engine.

It can work to your advantage if you do your homework and prepare for the use with all its oddities.

Posted: Wed Mar 12, 2008 10:55 am
by John Wallace
If you're referring to me, I said 'I' personally wouldn't use carbs. :D

I had 2 750 alcohol carbs for awhile.
Worked OK for awhile, then I had to spend a lot of time keeping it working.
Float needles started getting stuck, flooding over.
On the launch with the wheels up, the rear bowls would empty, the front would flood over into the venturis.
Something always happened, usually when I get to the money rounds. :shock:

Went to a Ron's Toilet injection and never had a problem since.
Just fill it up and go.

:D

Alcohol vs. Gasoline?

Posted: Wed Mar 12, 2008 11:23 pm
by bottlefed
If you are a really good bracket racer and have a really good car then alcohol is the obvious fuel of choice due to the consistency in changing weather conditions.

That said unless you have the tools to bracket race successfuly, alcohol is a pain in the ass...The fuel ( alcohol and water mixture ) will cause all kinds of problems for the fuel system. The carb will need to be designed completly for alcohol the boosters air bleeds emulsification tube etc. all need to be designed for alcohol. The fuel system will also have to meet the needs of an alcohol engine, this can be accomplished by the previously mentioned mechanical pump or by using an electric pump with a vacuum tapped regulator that will increase the fuel pressure as soon as the engine leaves idle. This is system will work very well, until the least little amount of residue gets on the vanes in the electric pump, then the fuel delivery will become erratic.

Then you have the option of a belt driven pump and bypass system. This will work much better as the belt driven pump is designed for alcohol use and will stand it a little better. The best thing to do is to drain the fuel after every meet and spray some lube through the pump whether it is belt driven or mechanical, the same goes for the carburetor.

Now on to the injection these systems work very well as far as lack of problems go but since they are mechanical they will not adjust for changes in air the way a carb will.

On to nitrous you can indeed use nitrous ( up to around 3-400 hp ) with alcohol but again the system will need to be engineered with alcohol in mind, solenoid size as well as seal material, to the design of the nozzle itlself.

As far as the injection goes, again with the nitrous carbs are the preffered setup since the mechanical injection will not respond to changes in intake signal that are produced when you hit the nitrous.

Long and short until you spend a lot of money on the car you will get a lot more bang for the buck using gasoline and nitrous. For the price of a decent fuel system and carb or injection you could replace your pistons with forged ones and install a plate system and purchase a drum of fuel.

Posted: Thu Mar 13, 2008 2:01 am
by ClassKing
Ron's Toilet is sooooo easy to use. Fourteen years and counting. Zero problems. Just flush the system at the end of the day. Pour a quart of gas in 'er to burn out the alcohol from the rings. Otherwise it will etch the cylinders. Use the fuel shutoff to keep it idling on gas cause it'll be pig rich til it burns off the gas.

You can hook up a little pump to pump fuel into the engine when first starting. Helps a bunch.

Re: How do I use Methanol in a Drag racing application?

Posted: Thu Mar 13, 2008 10:40 am
by Doug Schriefer
- Your compression is really too low to run methanol optimally (or for a bracket racing engine in general)... You'll need at least a few more points of compression for it to run best.

- Methanol will require about twice the volume of fuel vs. gasoline. The best way to do this is going to be with a belt driven fuel pump (so the fuel curve increases with the RPM) and a methanol calibrated carburetor.

There are Pros & Cons for running Methanol:
- Pros: Runs cooler, makes more torque, has a lower AFR ratio than gasoline (means you're ET is not going to vary as much).
- Cons: Longer to warm up if you race in cold weather, increased maintenance on the engine

- As far as using methanol with your N2O you have to options. If you're injecting a small amount of nitrous you can get a kit calibrated to run with Methanol as the enrichment fuel. If you're going to be using a lot, you'd want to use a small fuel cell with racing gas for the nitrous.

Posted: Thu Mar 13, 2008 6:48 pm
by Tod74
ninety3 wrote:
Tod74 wrote:Ron's Terminator
Rons Terminator??


I will be running with this comp ratio and carb for a while, as thats how I bought the motor. But when money allows, I will be making mods to it. If I go injection, I'd like to have a 6/71 under it first, so cant go too crazy with comp ratio there...
http://www.ronsfuel.com/terminator.cfm

Posted: Sat Jul 12, 2008 9:35 am
by TurboDiverArt
The car I bought last year was built for Methanol. I run it on gas because the previous owner had a new injection system on it and it would have cost me too much to purchase with that setup on the car. I had him switch the setup to a gas carb. I have thought about switching back to a Methanol setup. The car has currently run 8.90's on gas and should have a little more in it, we're still figuring things out. I've read about cars having a surge tank up front, what's this used for? My car has 2 mounting posts on the chassis that were used for this, plus a fuel door in the hood to access it. Can anyone educate me on its purpose?

Thanks,
Art.

Posted: Sat Jul 12, 2008 4:54 pm
by brket racer
Image
I've run my camaro on Alky ,with a carb,and a Product Engineering electric fuel pump for 7 years now with ZERO problems.I've been very successful with the car and will never switch back to gas.

Posted: Sat Jul 12, 2008 7:50 pm
by ClassKing
I've run 11.5 on alky and picked up over gas. PLUS had all of the other benfits. I don't know how low one can go, but I'd try it at 10.5. Bet it woulnd't hurt, and if it's cheaper....... 8)