Alcohol guidance

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ProNova
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Alcohol guidance

Postby ProNova » Sat Nov 15, 2008 7:37 pm

Ok since my introduction I have been busy and bought another car. It seems times are tough and deals are all over the place these days. I bought a car out of Memphis - 69 SS Nova, 498, BTE PG, all electronics, full tube chasis, fiberglass front and decklid, and nealry all lexan. The car is an alchohol car with an elderle (sp?) belt driven pump and an 850 4150 Holley carb and a vacuum release under the dash. I have never done anything with an alky car so I am kind of lost. Can anyone point me to some basics or advice? I want to give it a try because I dont want to dump the alky stuff for a dominator that I am comfortable with.

The cars last passes were at the Pinks arm drop in Tulsa and it ran 9.60 incomplete passes popping on the big end.

Thanks!
Only those that go too far, will ever know how far they can go.

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Leon
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Postby Leon » Sun Nov 16, 2008 12:21 pm

The popping is because its lean.Since its a carb,just tune normal.What pump? What jets?Certain size engine requires certain jet area.

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Bob Kraemer
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Postby Bob Kraemer » Sun Nov 16, 2008 2:43 pm

An 850 carb is no where near big enough for a 498 Big Block Chevy on alky.
Bob Kraemer

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ProNova
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Postby ProNova » Sun Nov 16, 2008 6:02 pm

I have no idea on what size jets are in it now. I will pull the carb apart and check them tomorrow since this cold is kicking my rear!

I kind of figured the carb might be way too small. What wold be the suggested starting point? I was thinking a 1050 and start with jets in the 140 range. I ordered the EGT today so that should help with the tuning.

The pump is belt driven and I believe it was called and Enderle???

One more thing. I noticed today that the fuel line goes straight from the pump to the fuel log and the regulator is after the fuel log with a #8 return line. To me and what I know from a first glance this seems ass backwards, but I guess its job is to regulate at X Pounds after the secondary log and return the rest to the tank???? I would guess I should do as I do with my nitrous car and flow the fuel side and verify it is working correctly.

Thanks!!!! ANy tips are extremely apreciated.
Only those that go too far, will ever know how far they can go.

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Leon
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Postby Leon » Sun Nov 16, 2008 8:51 pm

Need to know what model pump and pump flow besides jet sizes.

16martygearhead
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Postby 16martygearhead » Sun Oct 25, 2009 4:51 pm

Need to know what model pump and pump flow besides jet sizes.
i too purchased a 14.5.1 622 cu inch with alcohol enderle injected birdcatcher hat and am wondering how much loss of hp/ftlbs would i expect if i took it off and replaced it with another aluminum intake and a 1250 dominator.. motor is dynoed at 956 hp@6600 with 862 ftlbs@5000. dynoed with 1-7/8 pipe so numbers were a little down..thanx

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Weatherhound
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Methanol Induction

Postby Weatherhound » Wed Nov 04, 2009 11:32 am

Pro Nova,

The are big differences between conventional thinking with gasoline and methanol. Pretty much everything on the intake system needs to be much larger to get the most out of methanol. You will use about 1.8 times the amount of methanol than you will from gasoline. That means the intake charge density is much higher. Since liquids are not compressible, more room needs to be made to get enough air in the cylinders.

You need minimum 1.8 times more (AFR around 6.0:1), so carburetor applications begin finding handicaps when the HP levels approach 900. This is because there is so much wet flow required, fuel distribution and atomization begin to really hurt, and the parasitic drag of the large droplets basically shut down the flow potential. Dart has some flow comparisons for both wet and dry flow. Even with gasoline, flow tapers down on the flow bench.

On a relatively large displacement engine, an 850 CFM alky carb is too small. 1150 or more CFM, with float bowl extensions could be sufficient. The Enderle pump is most likely an 80A good for 6.9 gallons per minute at 8000 crankshaft RPM.

Typically methanol engines that pop out the exhaust on the top end are too rich (with injected applications). I would assume the same for carbs as well. It takes a lot to lean out a methanol engine to the point it pops out the exhaust. You would see a massive power loss and the engine would labor to climb in RPM. It would be safe to say that the carb is so small you are going to run too rich in the high end.


16Marty,

As far as injected applications, make sure you have the clearances set if you are not satisfied with your current HP levels. I have a bird catcher. The blade clearance is 0.006". The barrel valve leak down is around 15% using 100 psig air pressure. The high speed return in cooler weather is 0.100" and in the hot season 0.120". I have a 0.065" high speed dump poppet that kicks in around 6800 RPM. I am running an 80A belt drive pump with a Victor2 tunnel ram.

If you converted back to gasoline, I would make sure the heads have not been designed for only methanol applications. My 540 is using the BMF head from CFE with the 410cc intakes. That would be way too big for gasoline service unless I turned the engine to 10,000 RPM. If the engine was designed to run solely on methanol, you could lose a significant amount of HP and torque. It would be a good "all the time" nitrous engine.

Regards,
Brian

Blaumann
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Re: Alcohol guidance

Postby Blaumann » Sat Jan 22, 2011 1:32 am

Don't bother with a carb. get a toilet bowl. OR get hilborn stack type injectors. Simple and the best racing intake you will find.


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