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DEL51
10-11-2001, 12:00 AM
I was considering running alcohol in my 572 and have a few questions. What is considered an Ideal compression ratio and can you have any compromise on this?I have a 1471 littlefield,no high helix.Does this blower need some hard anodizing or other mods to work with alcohol?I heard that aluminum fuel tanks are out of the question,true? How do you determine the size of the injector hat.I was told that mechanical injection is "all or Nothing",meaning that you cant cruise at a mid range speed.What are the driving characteristics? Is there alot of blowby and oil contamination.Can this be used for regular boating.With all the crap going on in the middle east, alcohol may be the only alternative.Thanks,DEL51

Unchained
10-11-2001, 03:43 AM
I considered running alcohol in my 540 Arias and did considerable research on it.
1) You burn almost twice the fuel volume
2) Everything will corrode unless additives are put in the fuel.
3) You need to run at least 11:1 static compression.
4) The engine will want to run cold and foul plugs.
5) The fumes are nasty and burn your eyes.
I am going to open a can of worms on this one but I asked two different engine builders with dyno's how much more horsepower will I get on alcohol compared to gasoline. One said none. The other said 4%
The only way you get more HP with alcohol is that it will allow you to run a lot more blower boost without detonation. So the additional HP is with the blower, not the fuel. I haven't run alcohol (in the engine)
I just got this info from others.

nitro557
10-11-2001, 04:40 AM
gas burns at 14 parts air to 1 part fuel alc
at 6 parts air to 1 part fuel , you will make 1/3 more power on it and 10 time the maintenance , you can make ajustments in the fuel system to cruise but i tell you the oil dillution is bad it wont be a good lake toy motor, unless you make a couple of burps and put it on the trialer

ponponracing
10-11-2001, 05:32 AM
I did and I am still playing with some alky deal in my shop. I'll try to help.
You may run alky with any compression ratio you want, it will work, but you have to set the timing accordingly. I'm running 16/1 static compression ratio in my rig and it works like 13/1 except for the good hp and torque it gives. Yes it will destroy aluminum, including metering blocks, but also rubber line, al. fittings, etc.. But it's not a question of minutes...There are additives you mix with alky that kind of retard greatly corrosion. The exact double consumption make the motor run cooler, but you have to use a carb that flows double liquid. It can be bought from many carb shops. Mechanical injection (the real word is constant flow) work very good good as long as it is tuned right, but it's mainly designed for wot operation. Mine works like a carb, very good idling, off idle, mid range and wot. But you have to know how to tune them or the adress of a good engine tuner. In most cases, you will have a better luck with brand new units from the factory. I always dealed with Kinsler and when they took care of calibration, there was just a final tuning to be performed. With the increase in power, you will have to run more rings clearance, causing contamination when not running hard. Blowby also but nothing to get nut. Yes I would use alcohol for regular boating, but according to me the two major problems are first, you need double fuel capacity in your boat, and second where will you fill up? The very good thing is that by running higher comp. ratio you will be amazed by the fuel economy, and also you will be considered as a mean guy by running alky.
It won't really foul plugs unless you use the wrong heat range and you go idling for hours, in this case I recommend "kicker" outboard motor. Big powerfull high cam engines are not really designed for idling. If you run a low comp. ratio gas motor, you will gain torque and hp, but I can't tell by how much. Maybe if I stop spending hours answering this forum I will have time to make comparaison on dyno. You may run more boost with alky than with gas. You will gain performance from your blower by running it tighter with methanol. Fumes are nasty, but they are behind you, killing moskitoes (you have any in your area?) and discouraging cops trying to catch you.
I forgot, you don't see alcohol burning at day light, you'll get use to handling methanol. As a safety, I suggest wearing a triple layer Nomex suit, socks, gloves, head cap. The nice thing about that is that you will give that cutie a ride, you will have to help her get dressed. Nasty job but someone has to do it. You won't be stuck with overweighted one since they won't fit your spare suit.I do use methanol in my Chinese fondue burner, it works.
Where are you Blowndragboat, can you take over?

superdave013
10-11-2001, 06:10 AM
I have seen people switch blown gas engines over to alky and not change the compression. So it was low in the 8.5 range. The ran the blower soft and the boat still picked up lots over gas. They kept after me to switch but i never did. It's kinda hard to race blow gas with an alky burrner. Yes, my comp. would have noticed. I think that for lake use and not turnning your blower at 70% the oil contamination will not be as bad as what nitro557 is talking about. Hey, his deal is turned up like what you would see in a funny car! Sounds like fun but also race only. Even with blown gas and my turbo engines I change my oil alot. Did you see that Couger Tunnel in hot boat with the v-drive and the blown alky engine? The guy uses his for lake use only and he posts at this link. http://groups.yahoo.com/group/v-drive_boats
He can help give you some real world advice also as he is doing just what your wanting to do. Lower compression, soft on the blowe and it freaking screams! You should talk to him for sure.
Hey ponponracing, get off the board and on the dyno man! I want to see what you find out with the different compression ratios. I would like to take a 8.0 -1 deal and make some dyno pulls on gas, switch to alky and the power difference. Keep the blower boost the same and only adjust the fuel system and timming if needed.

BLOWNDRAGBOAT
10-11-2001, 08:19 AM
I am right here PONPON. Just watchin with a huge GRIN on my face. Hell, ya think I might learn something? LOL

ponponracing
10-11-2001, 10:24 AM
He Blowndragboat, stop grinning and talk. It's your world we are talking about. I'm sure you're dying to post your comments. I'm ready. I wasn't expecting you to learn something, but since I'm playing in your field, I'm expecting a hammer reply. Did I goof with: a:some of my answer, b:a little of my answer, c:most of my answer, d:all my answer, e:no goof here.
Superdave, my dynoman did some testing on low comp. motors that he switched to methanol. I'll try to make him talk and give me some comparisons. But I'm sure he didn't do it with blown motors.

superdave013
10-11-2001, 10:57 AM
Originally posted by ponponracing:
He Blowndragboat, stop grinning and talk. It's your world we are talking about. I'm sure you're dying to post your comments. I'm ready. I wasn't expecting you to learn something, but since I'm playing in your field, I'm expecting a hammer reply. Did I goof with: a:some of my answer, b:a little of my answer, c:most of my answer, d:all my answer, e:no goof here.
Superdave, my dynoman did some testing on low comp. motors that he switched to methanol. I'll try to make him talk and give me some comparisons. But I'm sure he didn't do it with blown motors.
Right on, But the blown stuff is what I'm intersted in mostly. I just saw what some of my bracket racer buddies did and it seemed to work pretty sweet for a low buck deal.
Man, my spelling sure sucks. Reading my post above is hard even for me! And I wrote it. I'm not as think as you dumb I am! haha

BLOWNDRAGBOAT
10-11-2001, 12:21 PM
Ok..let me get my thoughts togather so i don't talk for ever....Be right back

BLOWNDRAGBOAT
10-11-2001, 03:21 PM
Ok....Let me try to answer the original questions that DEL had. Then I will try to make a few recommendations based on MY experiance.
1st)Compression. As a rule of thumb, the perfect piston for blown gas engine's is 7-8:1 I like 7:1 simply because it gives me more flexability on on how much blower I feed it as well as timing. BOTH bosst and timing can be considerably effective on blower motors so compression ratio is criticle. On alcohol motors, you want your STATIC compression ratio at 10-12:1. Make sure it's a piston SPECIFIC for alky applications. You can go more but you better have a very VERY thick wallet. If you go past the recommended limits, your entering the PURE racing engine zone that have low operation cycles such as drag racing ONLY.
2nd) Your 14:71 is pretty damn big and when you operate it at a certain level of overdrive, it actually absorbs crankshaft horsepower just to drive it. Heres an example. On a topfuel engine that produces an estimated 6000 horsepower, it takes anywhere from 800-1000 crankshaft horsepower JUST TO TURN the blower at the speeds that are required to produce those kind of numbers. SO, it takes power to make power when you start dealing with upwards of 15-25 or more pounds of boost. Your 14:71 rotor's clearance's need to be setup tighter for alky use and while your at it, have it re-stripped. If you need it done, just send it to me and I can do it. Hard anodizing is recommended.
3)Aluminum tanks. Its a toss up but in my raceboat, I run aluminum tanks. Afterall, your fittings are aluminum, as is an injector hat and many other components. Aluminum heads ect..... I don't let alcohol sit in my tanks. I pump them out frequently to keep the corrosiveness to a minimum. There are several additives on the market that you can add to your fuel system to lubricate it and cut down on the corrosive nature of alcohol. Chances are you will blow your motor up or at the very least, have to pull it apart for some reason LONG before the alcohol can eat it up.
4)Injector hats are decided by the size of the motor,the amount of fuel the motor requires ect..... The four sizes are Bugcatcher,birdcatcher,buzzardcatcher and barndoor. For what your gonna do with the boat, a birdcatcher is more than enough. A bugcatcher will probably be plenty. It really depends on how it's setup and going to be used.
5) Mechanical injection is VERY responsive. Most alcohol motors are very crisp and instant in thottle response,partly due to the increased blower boost and the use of alcohol for fuel. When its set up properly, it can be a blast to drive. When its off your gonna hate it. It can be very tempermental and if your not experianced in basic tuning let alone blown alcohol motors, you might wanna re-think it. Mechanical injection can and does run extremely well, you just need to know how to tweek it when something isn't perfect. I have been working with an electronic fuel injection unit that is pretty sweet but its f**kin expensive!!! It is made by Enderle fuel injection and is based off of an injector hat with direct port nozzles. You can choose a 16 or 32 nozzle setup. It has an ecu that is pre-calibrated but can be tuned with a laptop pc.
6) Driving characteristics. When it's setup right, it will flatten your eyeballs in the back of your skull. If you don't think a boat can leave as hard if not harder than a racecar from a dead stop, just let me know and you can come ride in mine. I PROMISE you will leave the whole experiance with your nuts in your throat.
7) Not alot of blowby because you will need to run zero gapless rings as well as o-ringing the block and heads.
8) Oil WILL NEED to be changed alot since it can become contaminated. I run a straight weight racing oil from REDLINE. It's desiged JUST for alcohol motors.
9)IT can be used as regularly as any other boat BUT that depends on your level of knowledge and mechanical ability to weather or not its NORMAL which means there's nothing normal about alcohol engines. Even starting one CAN be a spectator sport in itself if your not familiar and have a self primer setup. Starting to get the picture?
I will start another post recommending what I would do if I was spending YOUR money. As far as the middle east is concerned, if things keep going the way there going, the last thing ANY of us are gonna need to worry about is a boat!!!!! PEACE!!!! Part 2 will start in a second. I need to go close up my shop.
[This message has been edited by BLOWNDRAGBOAT (edited October 11, 2001).]

ponponracing
10-11-2001, 04:04 PM
Blowndragboat, when you spit, you really spit! Good answer buddy, you're way more familiar than I am with blown alky motor. Looking for a brand new Kinsler Big Chief sequential E.F.I. made by Kieth Eickert? I have two on the shelf since many years.

BLOWNDRAGBOAT
10-11-2001, 04:18 PM
Before I get into part 2 Let me adress a few more MISCONCEPTIONS about alcohol engines. Yes the fumes will bother most normal people but people that run alcohol AREN'T NORMAL and that includes me. I use some scented fuel scented lubricant (Don't laugh it's true)that eliminates the bad fumes and actually makes it smell pretty good. Just don't stand there and PURPOSELY sniff it. Also, there's ALOT more to gain than 0 or 4% horsepower. IT's not just one thing that is making all the power, its SEVERAL things. The alcohol allows you to run more compression and much higher boost limits which obviously produce tons of horsepower. Alcohol engines also produce alot more torque across the rpm range. The second part of the equation is the cooling effect alcohol has on the intake charge. The intake charge is literaly trying to freeze which also creates a denser charge to the cylinders and that inturn helps build cylinder preasure and more torque/horsepower. Think of it like an intercooler. It is JUST as flamable racegas BUT it can be hard to detect. In the next few months there will be an additive that will allow an alcohol/methonal fire to be detected immeadiately. There have been alot or racers burnt badly by these types of fires but hopefully that will come to an end real soon. I (knock on wood) have never had a fire and hope I never do. Probably the biggest downside to alcohol is the cost. Not only does the fuel cost alot but the cost of building and maintaining a blown alcohol engine is astronomical. If you normally used about 20-30 gallons on a typical day at the lake, you will now use 40-60 gallons on a give day. I have 2 boats. A race boat AND a lake hotrod. If I only had 1 boat I damn sure wouldn't be running it on alcohol. If theres any other questions on alky motors just let me know. Blowndragboat@yahoo.com

BLOWNDRAGBOAT
10-11-2001, 04:56 PM
Ok DEL this is it for me. I think I have done my fair shar for one day. From the questions your asking, I gather you want a NASTY ass lake boat. Right or wrong? Considering the cost of building an alcohol motor, I will give you a few idea's that should give you some thoughtful alternatives.
If your already running a 572 motor than you KNOW what it can do. If I were building it for ya, I would put a 4.75:1 stroke crank in it which will give you a 605ci motor. I would build it @ 7:1 and run your blower on a superchiller and turn it around 7 pounds of boost. 7 pounds out of a 14:71 will produce massive amounts of torque. I would still fuel inject it with a birdcatcher but I would set it up to run on racegas for 2 reasons. Cost and reliability. Considering pump gas prices are getting upwards of 2 bucks a gallon and more in certain parts of the country, race gas is not much more that that. I run a MEGA cubic inch blower motor on race gas and the cost is not that bad all things considered. Even though I am running my raceboat on alcohol, it's just that...A RACEBOAT. I am buying 55 gal drums of VP racing gas for about 180 bucks MYCOST. That comes out to about 3.30 cents a gallon. So, considering thats not ALOT more than 92 pump gas, thats alot more attractive than running alcohol as a normal use lake boat. Running a 604 ci 14:71 blown and injected motor will be extremely nasty but alot of fun. You will still need to buy the same stuff (injector hat, fuel pump,fuel shutoff valve, barrel valve, surge tank, jets ect.....You will still have tuning issues to deal with and you will still have to setup an injector primer to fire light it off but thats no big deal. Anyway, I estimate around 1200hp and and a TON of torque depending on cam and head selection. If I had specific information I would be able to plug it into my program and get damn close on the numbers. Anyway, I hope this helps ya out. Let me know if I can help you any furthur. Seeya.

BLOWNDRAGBOAT
10-11-2001, 05:04 PM
Just when I thought it was safe to go to bed. Hey PONPON you didn't think I was gonna rip on ya earlier did ya? I consider you one of my Buds and aside from alittle ribbing here and there, I wouldn't ever be an asshole to any of my bud's. Hell, Chester's not even that bad. He's funny as hell to listen too. Anyway, I appreciate the compliment. I would be interested in the FI units you have. I even bet, since they have been sittin around for so long, I could talk ya out of them pretty easily!!!!!! I would love to test them on the dyno. I like to fiddle with stuff like that and get it to work on different combinations. Sorry it took me so long to get back to you guys earlier today. I had a bunch of people pullin me in 20 different directions. Let me know about the FI units. Talk to ya later.

Unchained
10-11-2001, 05:19 PM
I would like to see a dyno test on a blown engine running gas and then switched to alcohol. Same compression. Same blower boost. Of course the Alky engine would need to be richened up.

BLOWNDRAGBOAT
10-11-2001, 06:27 PM
ITs not as easy as your making it sound unchained. You can't just simply run one on a dyno and then change the fuel, fatten it up then run it again. It don't work that way. They are two different animals and need to be built differently. Pistons are a little different, rings are different,blowers need to be setup to run on different,cams are abit different,heads are setup different, ect. Just so many things are different that it's not easy as it would seem. Heres some food for thought....Why do you think IHRA/NHRA Pro-Mod cars have 2 different sets of rules and completely different engine packages? The nitrous guys run 15:1, have a 710ci maximum rule, naturally aspirated, racegas and several stages of nitrous. They also have a wieght advantage. The OTHER engine rule has NO compression ratio limit, 526 ci inchs MAX, 14:71 blowers, alcohol injected and a max of 35% overdrive. They are also heavier. My point is, these are 2 COMPLETELY different engines and run 2 COMPLETELY different fuels and they run heads up in the same class. So what would happen if you made the nitrous guys run the SAME 526 ci maximum rule but were allowed a little more compression on racegas and 5 stages of nitrous. Who would win? OR, what if they were identical. Both running the same 15:1 compression and blowers. The only difference is one is using alcohol and one is running race gas and nitrous? Who would win? The alcohol guys would win evertime. Why? One reason thats VERY obvious is the cooling effect itself is easily worth 150-200hp. So, to make things fair in promod racing is why the racegas/nitrous motors are allowed to be as much as 190 ci MORE than a blown alcohol motor. Makes ya think. If your still not convinced than I give up trying to expain it. PEACE

DEL51
10-12-2001, 12:20 AM
WOW,Thanks to everyone for the extensive amount of information. My 572 will stay a gas burner for a couple more years.If I were to build it for alcohol,I would make it a purpose built motor,I.E.BDB.No sense going half way.Here is my current setup on the 572.4.5 bore 4.5 stroke,Iron Merlin345cc CNC ported Roller cam,Jesel rockers and belt drive,7:5.1 comp,CP blower pistons with coating,Lunati crank and oliver rods,Stainless intake valve,2.25" inconel exhaust 1.94.BDS intake from Oddy,Cleaned up ports.1471 Littlefield w/1150 holleys and a vaccuum pump/puke tank.I do have a superchiller and am wondering how to set it up on the dyno. Alcohol engines sound like alot of fun and when I get the funds, I will give BDB A Call.Would the Injection increase the output over the dominators and would it be worth the cost?It sounds like a long learning curve but I think if I went to Kinsler,as previously suggessted,I could handle the minor tuning. I have another question about the injection.I have noticed that the alcohol setups inject from the top side of the blower and at the intake manifold.Do they do this when running gas as well? Can EFI be used in this fashion or is it restricted to topside only.What timing would be best with my current setup.I may change my cam. I have a little too much overlap.I was told by my engine builder this cam is his special grind. I hate that bullshit, is this a common practice?I would like some cam recommendations if possible.I currently have the engine out at the shop getting freshened. It did have a nice big surge, but it gets to be a hassle when idling up to te dock.Thanks again to everyone that replied!DEL51

superdave013
10-12-2001, 04:58 AM
BLOWNDRAGBOAT, MAD PORPS TO YOU MAN! I have read every post that you have ever made on this board. Yep, that's right I have done some reading. This has to be hands down the best, most informative post you have made to date. It confrims a lot of things that I thought were correct and straightend me out on some others. My last few engines were professionally built and the one I am working on now I am doing myself. It's a ---" turbo charged deal and I am fabbing up alot of the parts myself. (stuff like carb manifolds and the top plumun for the intercooler) I don't want this one to be nasty as I have been there and done that and I just happend to have some turbo's laying around. I am glad your on this board as you seem to be a good source of info and you don't mind sharing it! As time goes on I'm sure you'll be getting some questions from me.
[This message has been edited by superdave013 (edited October 12, 2001).]

BLOWNDRAGBOAT
10-12-2001, 08:33 AM
THANKS SUPERDAVE!! I appreciate the compliment. It's real hard to try to get your point across doing it like we all are but I try. Sometimes my posts get kinda long but to get into the finer details of this stuff and don't sound like an idiot, theres no other way. I am interested in the turbo setup your working on. I wish I had more experiance with them since they are more efficiant than blowers and are basicly doing the same job in a different way. THe turbo technology I have been checking out is gonna surpass blowers at some stage in the future. I know that's a bold statement but the reason I say that is this. Theres a guy racing in the NMCA and OUTLAW organizations and his name is Mike Moran. He is located in the Detroit area. Anyway, PHR did a cover story on him and his new 2000hp turbo motor in a pontiac T/A. Last I heard he was still shaking it down and was running VERY low 6's at over 200mph. It is one of the most impressive looking engines I have ever scene and I have scene alot! I wasn't a big turbo fan until I saw it for myself recently. He actually has to detune the motor because the damn motor creates SO much torque that he has been busting axles on the launch pad. That story is what got me interest up on learning more about twin turbo setups. They would be perfect for jetboats if you could map out the fuel curve. Keep me posted if you don't mind and thanks again for the props....PEACE!!!!!

superdave013
10-12-2001, 08:46 AM
I will keep you up to date for sure. I'll post photos when I get to that point. Keep in mind that this is not a drag race application. More like enderance. It's a 20' schiada v-drive with two 40 gal tanks! Hey, Now I can go all day long with out stoping for fuel.
I'm like you as I liked the throttle response that my blown injected deal had. But when I bought this boat it came with a crappy big block with a crappy old banks turbo set up. So I ran it for a season just like it was and liked it. It didn't make any boost untill 3,800rpm so it got great fuel ecomoney. No mufflers and the thing was so friggin quiet! If ya gotta run mufflers they might as well be turbos!

Unchained
10-28-2001, 06:14 AM
Where's the massive alcohol fuel horsepower advantage?
These engines have dyno sheets included.
These are in the Summit catalog. The engines
are from Bill Mitchell.
http://www.childsdale-ind-prop.com/BillMengines.jpg
The horsepower numbers are three lines up from the price. 25 hp more on alky. 3% more hp than gas. Hold me back.
[This message has been edited by Unchained (edited October 28, 2001).]

BLOWNDRAGBOAT
10-31-2001, 08:29 AM
I think we have gotten off the subject. We ORIGINALLY started talking about building a 14:71 blown 572. Once you throw a blower in the mix things change a ton. Once again, my point and comments were made around that fact alone. Bill Mitchell is selling alot of crate motors and he has packaged them in such a manner that the will eliminate most of the headaches with the idiots that buy these engines and blow them up. Theres a certain amount of these people that would actually expect a refund of some sort. Don't get me wrong, Bill puts out a great product but he is also opening himself up for alot more bullshit than I would want to deal with. What your chart shows are engines in comparable cubic inches and, without going into details, the only difference is type of fuel burned. Even thought the comparison is similar the alky motor DID make more power. Is it worth the extra cost involved all things being equal? I would say no but then again it depends on the usage of the motor. I PERSONALLY would have built the alky motor with ALOT more compression to extract more torque and hp. THIS is why alky motors make more power. It gives you the added advantages to allow a builder/racer to increase the compression and timing while DECREASING the possiblilty of detonation. Now, throw a blower in the mix and the differances of the 2 engines becomes significant. THAT WAS THE WHOLE POINT TO BEGIN WITH. I see and agree with what your saying. My question is why would you NOT take advantage of the effects that alky can provide and build your motor accordingly? For a pleasure boat that cruises the lake, I would recommend against. If your going to the lake to simply pull over to the hangout and race a few times and back to the trailer, then I would say go for it but make sure you know how to tune and maintain such a beast. So, think what you want and do what you want I just wish I lived closer so we could simply put your money where your mouth is. Make sure you bring your title and a crying towel. Just kiddin ya dude!!!

Unchained
10-31-2001, 03:30 PM
I agree, It seems that the additional HP to gotten from alky is directly related to the ability to run a lot higher cyl pressure without the detonation you would get with gas. At equal cyl pressures the difference in hp is minimal. Thanks for your input!!
I kind of thought that post would wake you up
http://free.***boat.net/ubb/tongue.gif

Dimarco Kid
11-06-2001, 07:01 PM
This blowndragboat guy sounds like he knows alot. Well, let me tell you sumpin' Sonny Jim Hot Biscuit! BDB don't wanna mess with tha Kid! He don't wanna go down that road! All I got to do is put mine together! And whoop some jet boat ass!
Hehehe, just thought since we hadn't talked much lately, I'd start some v-drive vs. jet drive shit!!! LOL Lovya BDB!
Kid