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Hey Ya'll

We're drag racers, but we run a stroked 360 in a Duster. So my dad is a MoPar man. He can't help it, I try to overlook it.

My dad has this friend with a Maverick that runs a 351W on Alcohol. Well, the last 5(!) engines this guy has had built for him have grendaded, this last one broke the crank in 3 places. So he called my dad to buy a block off of him and dad said, "No, but I'll give it to you if you'll let ME build your engine." [Al has been paying some joker to build his engines and dad's been telling him the dude isn't balancing it right. I could understand a fluke of one grenaded small block, but FIVE?]

Anyhow. So the job has been assigned to me to find out what I can about building an alcohol 351 that will withstand 650-700 horses.

What needs to be done to the bottom end? Billet main caps? Does it need to be drilled for anything?

Oiling gallery modifications needed?

How is a 351W balanced?

Any other pointers would be good.


If anybody has a site handy you could just point me to, that'd be great. I asked my dad what he needs specifically and he just said, "everything." He could be a little more vague I suppose.



Thanks in advance.


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<font color="deeppink">-Melissa-</font>
1978 Bronco Ranger XLT "Brutus"
1989 Bronco XLT "Mad Bronco"
<font color="blue">Built Ford Tough!</font>

<font size=-1>[ This Message was edited by: Effie on 9/20/06 10:51pm ]</font>
 

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Tell him to find an early 351 block they will handle 600+ easily in stock form. if he wants fill the block half way, good lightweight steel rod, forged crank and piston and call it a day. They are balanced 28oz factory.
 

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I've done a few alky 351w's. All with stock blocks. All had main girdles, were balanced (who knows if they were balanced PROPERLY...I didn't do it myself so I don't know for sure). The first was a .030" 351w stock crank/rods, SRP pistons at 14:1 compression give or take. Ran for 2 seasons when it blew the main webbing out of the block. I posted pics a while back. Ran 6.30's and some 20's in cold weather @ 110 mph best. Replaced that with a 414, filled block, girdle, 9000 scat crank. Ran about 2 tenths quicker and a few MPH faster. It had 450 runs on it and broke the crankshaft at the rear (which I hear is common with a lot of power and a scat iron crank) and pretty much took everythign else with it. Latest is a 414, 4340 crank/eagle rods/Mahle pistons. Only difference between this one and the last 414 was that this one is internally balanced. Runs about a tenth quicker give or take (6.0's at 114)...all 3 were in a '75 Maverick bracket car. I haven't run this one too much yet, just break in and one full bracket day, so it may grenade tomorrow or it may last 4 seasons...who knows.

The one that blew the main webs out was a E4AE block. The 414 was a D4AE block, and the one I have now is an E5TE I believe (forgot the number, but it is a later model block for sure). I have a C9 block out in the shed, but I'm debating whether to work it over or to just bend over & suck up the $2200 price tag for the Iron Eagle block.

One thing about alcohol is that it seems to be hard on crankshafts & blocks. Never had a rod bearing problem on any of mine, but I have had some block & crank failures...both on the Maverick and on my father's Fairmont (331). The new engine I have now; I turned the timing back a little bit, didnt' change ET or MPH at all, but maybe it'll help the engine live a little longer. At least until I can win the lottery & get that Iron Eagle block.
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<font size=-1>[ This Message was edited by: mavman on 9/21/06 7:08am ]</font>
 

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im pretty sure your gonna want an after market 351w block either from ford racing or some other source, stock windsor blocks and cranks just cant withstand the load of an alcohol race engine. if you want an engine that will last you gotta go aftermarket for block crank and rods.
 

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I disagree on the need to go aftermarket on the block for what you want to achieve. Crank, well thats obvious, same with the rods
 

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I agree with Woody. Gf's brother has a 408W using an early block that has been alive and well for almost 8 yrs now while running 5.80's in the 1/8. His only issue to date has been the crown of one piston was too thin and broke. However, the motor prior to this one he tried to "cheap out" and use a cast crank. It didnt last long before it became a multi-piece crank.
 

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500 dollar 4340 scat crank, 400 dollar rod and a 69-70 block and call it good easily.
 

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You can make a lot of power for a long time with a stock 351 block. Unfortunetely, sooner or latter the thing is going to come apart. My dad's 69 351 ran for about 4 years making between 550 and 600hp. The oil pressure started acting funny. When he tore it down, it was split right down the middle. Three of the cam bearing came out with the cam. The #2 and #3 main saddles you could wiggle with your fingers. The block had 4 of the 5 main webs cracked BAD. It was actually cracked on the outside of the block above the pan rail too. One more pass and he would have lost everything. The block was filled and studded, but not girdled. There were actually flakes of metal on the main studs where the caps were moving so much. This was a 13.5 comp., stock stroke, engine. He normally only turned about 7200-7400rpm. He wants to build a stroker. He has 2 other 69 blocks, but I don't think he will use them now.
 

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This is for fordmatt, do you know if your father would be interested in selling one of his 69 windsor blocks and also does he have one that would clean up with a 4.020in bore? Thanks, from Ken
 

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What compression for alcohol and what needs changing? My 427 is 15 to one compression I'm putting together and was thinking of alcohol but heard it burns twice as much alcohol than race fuel!
 

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yup, sure does. alky $2.20/gal x 2 = $4.40 per gasoline gallon. whats the price of the grade of gas 15:1 needs ? $9/gal, maybe? go shop for prices in your area.

from what ive heard, alky in a n/a engine seems to be kindest on an engine between 11:1 & 15:1, so you might want to stay on the short side of 15:1 if you can. the higher the c/r, the greater the risk of hydraulicing a cylinder due to the amount of fuel being passed thru it, ive been told. some people also feel that a 2 step should not be used for the same reason. jmho.
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<font size=-1>[ This Message was edited by: igo1090 on 9/23/06 9:56pm ]</font>
 

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On 2006-09-23 06:49, igo1090 wrote:
from what ive heard, alky in a n/a engine seems to be kindest on an engine between 11:1 & 15:1, so you might want to stay on the short side of 15:1 if you can. the higher the c/r, the greater the risk of hydraulicing a cylinder due to the amount of fuel being passed thru it, ive been told. some people also feel that a 2 step should not be used for the same reason. jmho.
We have to separate a carb from injection here. With mechanical injection, a 2 step CAN cause problems with extremely high compression ratios. When you mat the gas with the engine running (for instance) 4000 RPM, the barrel valve is wide open, and the engine is getting almost maximum fuel flow. It still depends on the engine as some higher HP applications (especially smaller inch small blocks) can have very little volume in the chamber in order to achieve the high compression ratio. Most injection companies make/sell what is called a converter helper, which cuts a little fuel when on the 2 step. It was designed to stop the backfiring & loading up while on the 2 step, but by design it can also help with overfueling and engine.

Hydraulic locking for 99.9999% of us is not a concern! Where the problem occurs is in Nitro engines. Nitro "likes" about a 1.7: a/f ratio, so there can be a huge amount of fuel in the cylinder at the time of combustion. I do know that in Top Fuel classes that a cylinder misfire can lead to lifted heads, blown out gaskets, and a few years ago I saw one even LOSE a head (broke the studs due to the pressure). That's why top fuel harleys need head restraints. Misfire=bad news on 2 wheels.

A carburetor application won't have to worry about it one bit. The engine will only flow so much air and by design a carb won't over fuel it unless a jet falls out or something odd like that.

IMO, it doesn't matter if you're building for alky or gas; keep the compression ratio within reason and you'll be fine.
 

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wouldnt want to disagree, mavman, but i and a few others running alky carbs found that ditching the 2 step doubled to tripled our rod bearing life. we figured it had to do with the fact that the randomly dropped cylinders were trying to compress & pass a full unburned charge past tdc was possibly hammering the bearings a tad more. bearing crush seems to last a good bit longer, but who really knows?
 

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Just to add my .02.....

My alky use is not quite double that of gas. I use about 1.75 gallons of methanol from the trailer to staging, start in staging early to keep it warm, burnout, 1/8 pass on a 1/4 track, and back to the trailer. About 1 mile round trip.

The cost has gone up a little recently. I bought 2 drums two weeks ago. $135 each. so......110 gallons/$270 = $2.45 gallon. I also add about $6 per drum worth of Klotz synthetic top lube.

Methanol will work with 15:1, 14: 1 is about perfect, but my 12.7 557 BBF does just fine as well. It's 12.7 with flat tops, 4.5 stroke and 80cc chambers.

I've had zero problems using mechanical injection (Flying Toilet) and a two step. I two-step it at 4200, but I do wait until my side of the tree comes down before I go on the two step. I'm only on it for about 1 sec or less. My bearings
looked great after two full bracket seasons. Well, great for an alky motor. A few scratches from unknown junk, but not pounded. My bearings:
 

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dave c - its not so much a visible problem. mike the width of the bearings in the center and ends. if center is wider, you are losing the crush fit on the bearing. sometimes after the crush fit is lost, the rod tries to exit the block.
 
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