Carburetor Help for Alcohol

[Colorado #28]

Hello,

Im having trouble finding the right Jet combination for my Alcohol Carburetor... I have a Demon 750...When i ran in Colorado and Kansas i had 160 Jets in the front and 160 jets in the rear. I'm now in Georgia and im having trouble finding what jets to run..Ive tried 168 in the front and 172 in the rear.. Car still runs hot and lean. I put 172 in the front and 172 in the rear car ran over 200 degrees and now i have a burnt piston...I dont want to make the same mistake with the next engine..Any help will be greatly appreciated..Thanks

V/R Rick

[clm15]

I been told that going up on jets can make a alky engine run hot to. seems odd but alky dont lube well. I have had fuel lines that are soft,this will starve the engine for the proper amount of fuel.
Some belt drive pumps cavitate, Our carb guy wanted us to sell the pump,and get the procam block mounted pump. We have a vacum operated regulator. Our motors in the 650hp range. have a hard time getting it hot. got a Willys adj jet carb.
Willys sells all the parts you need.

Something else to look at,Alky atracks moisture bigtime. Make sure the fuel is fresh.That mite be the hole problem. Buying alky at the racetrack out of there pumps is not a good deal. not many of us run alky. ask around. Sprint cars still do. I even put a decident filter on my breather. You can get one from a auto paint supply store. They have them on the counter and its used on the air line to the paint gun.

[joeltjen]

be sure and check your fuel filter, the good stainless steel ones, which you should be running anyway,( paper ones have no place in racing, jmo) will actually hold water inside them, shake it or compair the weight with a new one, you might be surprized.

[clm15]

funny you said that. I have ran a paper one for years .We change them at 400 laps. Got to the track yesterday started the engine,and fuel pressure was low. Played with regulator and at idle it had more then when you rev it.

guess what! Changed the filter and back to normal! I did put another paper one in,all we had.But Ill get the steel one this week.
Big trucks have water seperator's on them I wonder if that could work for racing fuel? Million dollar idea?
Leared we been getting recycled fuel. It was cheaper,but not that much. Watch the fuel you buy!

[joeltjen]

seems like the stainless steel ones do trap the water like a big truck water separator, i get mine from speedway motors and i think they are only like $20.

[Colorado #28]

Hello,

Im having trouble finding the right Jet combination for my Alcohol Carburetor... I have a Demon 750...When i ran in Colorado and Kansas i had 160 Jets in the front and 160 jets in the rear. I'm now in Georgia and im having trouble finding what jets to run..Ive tried 168 in the front and 172 in the rear.. Car still runs hot and lean. I put 172 in the front and 172 in the rear car ran over 200 degrees and now i have a burnt piston...I dont want to make the same mistake with the next engine..Any help will be greatly appreciated..Thanks

V/R Rick

Thanks for the replys...What Jets are people using that have Alcohol Carburetors here in the South? What are the Front and Back Jets? Im thinking of trying 180 in the Front and Back for a starting point...Anybody have any ideas? Thanks

[28m]

North, East, South, west...doesnt matter. It all depends on your elevation. I run 186's with similar HP at 1100 ft above sea level. Someone earlier said they thought too big jets would make you run hot...it can make your exhaust temps go up but not your water temps. Your water temp will fall with more fuel. With all this being said, not a good idea to tune your motor with water temps. Best way is with a $ 150 pyrometer...MONEY WELL SPENT. If not, do plug checks with new plugs. You are looking for heat on the threads of the plug. Color 3 threads down the plug is good. If you dont know how to read plugs, pull a plug and find a motor guy in the pits and ask him to read it for you.

Paper filters with alky are only good for 2 nights and you have to change them. After that, the flow starts to restrict. Spend the extra for the stainless and take out the worry of the paper breaking down with alky.

4000 feet to 1000 feet is HUGE. Dont be affraid to step into the 180's

[Colorado #28]

28M,

Thanks.....I will start this weekend in the 180"s....I appreciate your help...Ya comming from 10,000 above sea level down to sea level has been rough on me because alot of people dont run alcohol down here and they cant help me.. Again thanks...

V/R Rick

[grtmod3d]

what track are you running at in GA that has Mods.

[Colorado #28]

Were Running Mods at East Alabama Motor Speedway in Phenix city...We will be running a Modified show this weekend at 441 Dublin speedway on Saturday. Their paying $1000.00 to win and a $150.00 to start...Then on Sunday we will be racing at EAMS in Phenix city..The tires though are the G60 tires...Come on and Race with us...

V/R Rick

[clm15]

We are looking at moving sometime this fall,to the charlotte NC area. (Collage) I love the Mods, and hope we can find a track close to where we end up living.
Up here in Ohio/Pa, we get 30 to 70 cars depending on the money to win. I see there is a series, for the Mods in NC, but it don't seem to have a big following?

Hey Colorado 28, How many cars in your area? Goodluck this weekend!

[grtmod3d]

I've heard of EAMS. I live in North West Florida and a few of our guys go up there for the State and National races at the end of the year. I use to live in NC and wne to NTI and there are only 2 tracks near the charlotte area that run mods. and they are Carolina speedway in gastonia,nc East Lincoln speedway in Stanly,nc ray everham owns that track. both tracks run on goodyear tires though.