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Discussion Starter #1 (Edited)
I am new to the world of high HP motors and I was reading another thread and got me to thinking. That in it’s self is scary. Most of you guys have forgotten more than I know so please try and tolerate my question.
I saw that a guy had a 12:1 BBC and wanted to know if he could add a blower to it and run Race Gas. Everyone said no but it would work on Alcohol. What are the pro’s and cons of Alcohol VS race fuel? Again I know jack $hit about this and I am trying to edgemakate myself.
I just got a 74 Hondo Shovelnose and I am going to run BBC in it and I am trying to learn all options for power now and down the road.
TIA

Stuart
 

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mo balls than $cents$
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if you can get methanol cheaply, go for it, you'll have a hardtime matching a blown gas motor up against a blown alky:)grn:)grn you'll just be wearing rings alil more and may have to change your oil couple times more per summer, that's about it. the alky tuning window is pretty big too, which is nice.
 

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Discussion Starter #3
Again pardon my ignorance, but if it is that similar then why do not more people run alky motors? Do you get more power from it or is it a simple fact that you can run high compression ratios which will equal more hp/trq per ci? What does it cost to run alky ($per gallon) does the motor consume it at a higher rate?
 

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Again pardon my ignorance, but if it is that similar then why do not more people run alky motors? Do you get more power from it or is it a simple fact that you can run high compression ratios which will equal more hp/trq per ci? What does it cost to run alky ($per gallon) does the motor consume it at a higher rate?
all my alky experience is with dirt modifieds, but yeah basically you can get away with more compression and timing, even when blown.the extra power comes from the methanol cooling effect on the charge temperature and being able to run a full timing curve. if you're doin a hydro, a blown alky motor is about as good as it gets for em. you'll use roughly 30-50% more methanol than racegas, running costs are close to the same but methanol is cheaper per drum, round 200-220 a drum, but the blown gas will never make the power it could at 12 to 1 on alky:)grn:)grn
 

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The high compression blown alcohol engines work well but the tune up window becomes very small. As compared to a 9:1 blown alcohol engine.

If you are a good tuner and can adapt to weather conditions or traveling then go for it.

For the most part a pleasure 9:1 blown alcohol deal rarely needs the tuneup adjusted if you boat in the same area all year.
 

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might be pretty small window down there at sea level too, i didn't think about that:)sphss
 

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Discussion Starter #7
The high compression blown alcohol engines work well but the tune up window becomes very small. As compared to a 9:1 blown alcohol engine.

If you are a good tuner and can adapt to weather conditions or traveling then go for it.

For the most part a pleasure 9:1 blown alcohol deal rarely needs the tuneup adjusted if you boat in the same area all year.
I am not a good tuner i can hardly get my junk to start once i put a wrench on it..

It is not so much i want to bulid a blown alky deal just wondering the difference between the two. I am looking into buliding a blown gas motor along with a few other routes, but if alky was a bigger bang for the buck then maybe so??
 

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Yes it is a bigger bang for the buck just keep the compression within reason.

I am not a good tuner i can hardly get my junk to start once i put a wrench on it..

It is not so much i want to bulid a blown alky deal just wondering the difference between the two. I am looking into buliding a blown gas motor along with a few other routes, but if alky was a bigger bang for the buck then maybe so??
 

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I am new to the world of high HP motors and I was reading another thread and got me to thinking. That in it’s self is scary. Most of you guys have forgotten more than I know so please try and tolerate my question.
I saw that a guy had a 12:1 BBC and wanted to know if he could add a blower to it and run Race Gas. Everyone said no but it would work on Alcohol. What are the pro’s and cons of Alcohol VS race fuel? Again I know jack $hit about this and I am trying to edgemakate myself.
I just got a 74 Hondo Shovelnose and I am going to run BBC in it and I am trying to learn all options for power now and down the road.
TIA

Stuart


Alky doesnt like more than 11:1 with much Blower on it, if you are talking say a direct setup and 12:1 you can prolly get by with it if you're running water heads, make sure you have circulation and you can prolly get by Ok, if this is a drag boat or hot lake deal, you just have to back timing off with a better blower. if you are talking an LS6 type dome, 36 is about max for it timining wise, but it's going to depend on how good the blower is, and there is a LOT of variables with Blowers, sizes, clearances and effeciency.
 

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blower

I run my 468 with 12to1 compression on alcohol with a 1471 moonyham blower at 26psi my motor runs great have been running it for 2 years now
 

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you mean the 200 series ?...I like all their stuff, but I think the injectors could still be bigger.
We will be running one on my son's 532ci. Pontiac ( if this economy ever picks back up) Still need to get a hat for it & wrist pins...
 

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Again pardon my ignorance, but if it is that similar then why do not more people run alky motors? Do you get more power from it or is it a simple fact that you can run high compression ratios which will equal more hp/trq per ci? What does it cost to run alky ($per gallon) does the motor consume it at a higher rate?
1 , because they are used to gasoline.( the unknown )
2 , if you took a motor and switched JUST FUEL you would gain aprox 5% hp and maybe 10% torque, ( depending on application ),,
3 , alky is aprox $2.50 a gallon compared to race gas ( $7.5-$9'50 a gallon), on N/a motor aprox 1.35 times the amount of fuel , on blown aprox 1.7 times the amount of fuel,,,
4 , You can run a lil more timing, the tune window is wider,,
5 , when you are done running for the weekend you need to clean out the fuel system ( and spray a lil wd or marvel oil in her ,,:mad::mad:,,lol.......Eric:)hand
 

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Discussion Starter #16
I am kinda leaning to a 496 with a blower maybe next year added to it?
 

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Discussion Starter #18
1 , because they are used to gasoline.( the unknown )
2 , if you took a motor and switched JUST FUEL you would gain aprox 5% hp and maybe 10% torque, ( depending on application ),,
3 , alky is aprox $2.50 a gallon compared to race gas ( $7.5-$9'50 a gallon), on N/a motor aprox 1.35 times the amount of fuel , on blown aprox 1.7 times the amount of fuel,,,
4 , You can run a lil more timing, the tune window is wider,,
5 , when you are done running for the weekend you need to clean out the fuel system ( and spray a lil wd or marvel oil in her ,,:mad::mad:,,lol.......Eric:)hand
Is this done to lube the cylinder walls due to lack of oil in the fuel?
 

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If you run a lil on the fat side it will run cooler and not hurt anything,, if you have the tune right I can run the oil all year ( lake use )
 

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Discussion Starter #20
If you run a lil on the fat side it will run cooler and not hurt anything,, if you have the tune right I can run the oil all year ( lake use )
I am wanting a "lake" hot rod that is all. The shovelnose i picked up has inboard steering and do not want to "race" balls out. might be fun to race a few local deals just for the heck of it. Would like to see the 8-9 range on HP. 2 bolt GM block Dart Pro 1 heads 496?
 
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