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-   -   Changing an alcohol engine over to gas (https://www.racingjunk.com/forums/showthread.php?t=21026)

dcress1127 06-07-2008 02:55 PM

Changing an alcohol engine over to gas
 
I have an engine built to run on alcohol. Can I just change the fuel system over to allow it to burn gas or must I make other changes too.

This was an engine built for dragracing and now will be prostreeted and it is just not practical to run alcohol.

Thanks for any input.

Gods Grace,
David

OneBadGMC 06-07-2008 03:17 PM

Kind of depends...

Many alky engines are built without valve seals. This lets the motor pull a little oil through to help keep the top lubes. If yours doesn't have any, you'll need to add them back for street use.

Whats the compression ratio? Are you wanting to run it on pump gas or race gas? If race gas, you may as well leave it on alky, as it'll be cheaper and run cooler.

Speaking of cooler, how big is the radiator? Alky doesn't require nearly as much cooling capacity as gas.

dcress1127 06-08-2008 07:13 AM


Originally Posted by OneBadGMC
Kind of depends...

Many alky engines are built without valve seals. This lets the motor pull a little oil through to help keep the top lubes. If yours doesn't have any, you'll need to add them back for street use.

Whats the compression ratio? Are you wanting to run it on pump gas or race gas? If race gas, you may as well leave it on alky, as it'll be cheaper and run cooler.

Speaking of cooler, how big is the radiator? Alky doesn't require nearly as much cooling capacity as gas.

The radiator is plenty big to cool it. Since it has a blower the compression is 9-1. Problem with alcohol is: I have to buy it by the barrel and pump it myself which, would be okay, but because of ordiance and covenant I can't keep a barrel of fuel in the garage. I thought it might be cheaper to change the motor over than to sell it and buy another motor. Sure appreciate the help.

This motor had just two passes on it when I bought it from a guy who had to quit racing due to a divorce. I told him I would hold it for a year and sell it back at the same price if he could get on his feet and now he told me he won't be able to do that and I am into it way cheap so, figured to put it in a street car of some kind.

hammertime 06-08-2008 08:06 AM

The carb should just be a easy swap, may need to change timing/plugs though. Fuel system should be good for gas if it was good for alky.

OneBadGMC 06-08-2008 09:13 AM


Originally Posted by dcress1127

Originally Posted by OneBadGMC
Kind of depends...

Many alky engines are built without valve seals. This lets the motor pull a little oil through to help keep the top lubes. If yours doesn't have any, you'll need to add them back for street use.

Whats the compression ratio? Are you wanting to run it on pump gas or race gas? If race gas, you may as well leave it on alky, as it'll be cheaper and run cooler.

Speaking of cooler, how big is the radiator? Alky doesn't require nearly as much cooling capacity as gas.

The radiator is plenty big to cool it. Since it has a blower the compression is 9-1. Problem with alcohol is: I have to buy it by the barrel and pump it myself which, would be okay, but because of ordiance and covenant I can't keep a barrel of fuel in the garage. I thought it might be cheaper to change the motor over than to sell it and buy another motor. Sure appreciate the help.

This motor had just two passes on it when I bought it from a guy who had to quit racing due to a divorce. I told him I would hold it for a year and sell it back at the same price if he could get on his feet and now he told me he won't be able to do that and I am into it way cheap so, figured to put it in a street car of some kind.

You didn't say it was blown. If this is a injected motor, you're going to spend a TON of money to convert it over to gas.

If it's injected, plan on buying a new set of nozzles (which is the cheap part), plus a new fuel pump (about 300-600, depending if you buy good used or new).

If the blower is setup for alky only, you can potentially ruin it on gas. Alky blowers have clearances setup quite a bit tighter than gas blowers. If you switch it over to gas and it doesn't have the proper clearances, plan on locking the rotors up inside the housing, trashing the blower and probably ripping your crank snout off at the same time.

Gas for a blower motor is going to be considerably more expensive than alky. I just bought a drum (which I store here at the house), and it ran me 3.00/gallon for 99.99% alky. Thats about the equivelant of 6.00 gas. 6.00/gallon gas will NOT run a motor setup for blown alky. Plan on buying C16, which is considerably more expensive.

You'd be better off renting a storage bin and keeping the alky in there.

dcress1127 06-08-2008 01:19 PM

Thanks guys. I've made up my mind that if I keep the motor, I am going to keep it on alcohol. A friend of mine runs a repair shop and can keep a barrel for me there. Otherwise I'll sell this motor and buy a gas burner. This rascal was put together nice and is beautiful to look at. I know my friend lost some big money on this thing, but with the divorce he really lost all the way around and I wanted him to be able to get it back. If I sold it now, I feel like I should give him the difference because I've been the divorce route too. Anyway, for now, its keep it as is. Thanks for help.


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