Stroker Crank worth it?

louisb

Senior Member
Hi,

Planning out my 8ba build for my AV8 roadster project and I am wondering, all other things being equal, is the extra 16 ci from a 4" stroker crank worth the money. Does it really make a lot of difference for the added cost? Would you be able to tell by the seat of the pants?

Thanks,

--louis
 
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Merc cranks are not that hard to find at a decent price, unless your talking a new SCAT crank. Me personally, I think it makes a difference. It has always been said you can't beat cubic inches for added power.
And I think it's more than seven, I've got a 4" crank with .080 over pistons and it comes out to 265 CI.
 
Ford thought so! As have generations of Hot Rodders. Not sure where your getting the 7 ci from, 235-221=14 & 255-239=16.
 
Your right it is 16 ci more. 3 5/16 bore, 3 3/4 is 258 vs 274 for the 4" stroke. What I get for posting before my second cup of coffee.

--louis
 
As Ralph pointed out, cubic inches (and compression ratios) are some of the major factors you have to work with on a flathead V8.
 
So what is the going price for a good merc crank these days? The Scat cranks are $700 and I read they have ballancing issues.

--louis
 
I would think you can find one for $2-300.00. I have a couple that came in complete blocks I bought for less. Just make sure it has enough meat left on it to turn it. I could sell you one of mine, but the shipping would be atrocious.
 
Yeah shipping would be pretty high and I am broke from Christmas anyway. Thanks for the input.

Thanks,

--louis
 
The time to ask if it was worth it is when someone with a 4 cyl. car with less than half the cubic inches blows your doors off. Do it for bragging rights only.
 
louisb,
Search around for Vic Piano, a good guy, here on the Barn. He resides in Fla
and may have what you need. Go back a page or two and look for Vic's post............
'What I did on my lunch hour'............might be a short cut.
Charlie ny
 
That was kind of my thinking. I want the car to be sporty and fun to drive. Only racing it would see would be at something like TROG or the Hill Climb. I have Ron's and JW's books which have a lot of info but I don't think they really talk about the power difference of a stroker. Frank Oddo's book seems to indicate it may not be worth it for a street car.

--Louis
 
louisb,
Search around for Vic Piano, a good guy, here on the Barn. He resides in Fla
and may have what you need. Go back a page or two and look for Vic's post............
'What I did on my lunch hour'............might be a short cut.
Charlie ny

Will do, thanks for the heads up.

--louis
 
You have to add that you might have to grind the journals....

4 1/4 scat crank and 3 5/16 ( instead of 0,08 inch overbore) gets you 293 ci ......
Keep the stock rods
 
I have a 41/4 stroke crank with a 35/16 bore flatty in my 46 merc.with a Columbia rear.Its a torque monster! Well worth the expense.It has a Scatt crank which although was supposedly factory balanced ,was no where close to being right.Phil
 
Hi,

Planning out my 8ba build for my AV8 roadster project and I am wondering, all other things being equal, is the extra 16 ci from a 4" stroker crank worth the money. Does it really make a lot of difference for the added cost? Would you be able to tell by the seat of the pants?

Thanks,

--louis

Hi Louis, go the stroker route, it's the best way to wake up these Flatties.

We get more demand for the 1/4" longer stroke (on the 4.000" Merc platform) than any other size. Once in a while we sell the 4.125" also, but mostly the 1/4" deal.

These builds will place you in the neighborhood of 150/160 HP with over 260 Ft.Lbs Torque, depending on ALL the peripheral pieces.

We use ONLY the Eagle cranks, Scat rods, and the Ross pistons with the "metric" ring pack! We choose to NOT use the Scat crank OR the Eagle rods!

Better to have a little extra power than not enough in the end!

Thanks, Gary in N.Y.

P.S. Everyone here have a safe and Happy New Year! I would also like to thank everyone who has dealt with us this past year, helps keep this hobby alive!
 
I personally believe increasing the stroke is the best bang for your buck. Shoot, I bought a new pair of aluminum heads and the ARP studs cost more then the heads!
 
I personally think aluminum heads are more trouble than they are worth.with the over bore and increased stoke the CR is automatically increased,adding HC heads to the mix tends to elevate you to the impractical.my engine has slightly milled 59ab heads set at .050 clearance pistons and valves.Like I previously stated ,is very Torquey and performs well.Phil
 
I have a couple of sets of EAB heads I was planning to use. Intake will be an early Fenton super dual with 97s. Cam is still up in the air but I hear good things about the 1007b and I think that will work with stock heads. (Let's not restart the cam debate please lol)

This will be backed up with a stock '39 trans and a 40 rear with 3.75 gears. Should be a fun package in a light A roadster. Sorry if that is to much HAMB related stuff for the Ford Barn.

--louis
 
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