Eagle 4.25" stroker crank

[360duster]

Hello Guys, just found out that Eagle has got a forged SBM crank with 4.250" stroke length:

https://www.eaglerod.com/item/5674114-4340-crank-chry-360-4250-stroke?category=294327

Anybody did a stroker with this one and could supply the used parts / info about how much clearance work was necessary in a production block?

Running a 4" stroke at the moment, just thinking about future upgrades.

Michael

 

[Garrett Ellison]

Uses small block chevrolet 6.2 inch minimum rod length, so there are probably some lightweight rods that wouldn't need much block clearancing. What cylinder heads are you using or are you planning on with these?

 

[B3422w5]

Maybe it’s just me, but without exotic heads(W8/9) type stuff I wonder how worth it that stroke is over a 4 inch.
To me, the 4 inch knocks a lot of rpm out of a typical build already, and offers tons of torque.

 

[Scampin]

I went from a 4" to a 4.125" stroke just to get a few more cubic inches, rpm wise I was expecting it to not like much past 6k but it has proven it goes quicker shifting into the 7k range. I don't have any regrets going with the bigger arm.

 

[Demonx2]

Maybe it’s just me, but without exotic heads(W8/9) type stuff I wonder how worth it that stroke is over a 4 inch.
To me, the 4 inch knocks a lot of rpm out of a typical build already, and offers tons of torque.

Me likes big torque!!

 

[RustyRatRod]

Maybe it’s just me, but without exotic heads(W8/9) type stuff I wonder how worth it that stroke is over a 4 inch.
To me, the 4 inch knocks a lot of rpm out of a typical build already, and offers tons of torque.

Think truck motor.

 

[360duster]

Uses small block chevrolet 6.2 inch rods, so there are probably some lightweight rods that wouldn't need much clock clearancing. What cylinder heads are you using or are you planning on with these?

It´s just sth. in my mind if i update my engine. I do have a good set of Indy rectangular port heads with their intake, still running a scat cast crank and KB hyper pistons - one day i´ll change this stuff out. I know there´s also the Molnar Crank / Rods with the smaller Honda Journals, just curious because i never heard about somebody doing a build with this eagle crank.

 

[Garrett Ellison]

It would have to be worth something just because of reduction in piston mass. Use a 6.3 inch or the longest available rod to maximize that benefit.

 

[Garrett Ellison]

You’ve got enough cylinder head to support it, so I would say to “GO FOR IT!” But.. like yourself I would want to see someone else find any potential reliability issues first.

 

[360duster]

not only reliability issues....it´s more the clearancing work and parts combinations that i´d like to know. Rod Bloomer sold some 4.25" cranks and complete assemblies....so i´m pretty sure some guys here did such "big SB strokers".

 

[tvt59]

Hello Guys, just found out that Eagle has got a forged SBM crank with 4.250" stroke length:

http://[URL]https://www.eaglerod.com/item/5674114-4340-crank-chry-360-4250-stroke?category=294327

[/URL]

Anybody did a stroker with this one and could supply the used parts / info about how much clearance work was necessary in a production block?

Running a 4" stroke at the moment, just thinking about future upgrades.

Michael

There's a lot of these engines out there. Rod used to sell these cranks and he sold out of them. My Bloomer headed engine with the 4.125" crank still revs good. But I figure you'd at least need the next higher hp head after the Bloomers. But it might surprise you.

 

[33IMP]

An acquaintance of mine ran a 471" sbm for several years. No durability problems that I know of. Nine second street driven 71 demon. The one pass heads up against him, I got to the finish line first..... but I had to redlight to do it, lol .
His 501 (or was it 502?) sbm didn't last. Too many too-light components.
The bigger the small block you build the bigger/better heads you need.
Don't put a 225cfm head on a 440 inch motor like Mopar did.

 

[B3422w5]

An acquaintance of mine ran a 471" sbm for several years. No durability problems that I know of. Nine second street driven 71 demon. The one pass heads up against him, I got to the finish line first..... but I had to redlight to do it, lol .
His 501 (or was it 502?) sbm didn't last. Too many too-light components.
The bigger the small block you build the bigger/better heads you need.
Don't put a 225cfm head on a 440 inch motor like Mopar did.

Think his 500 inch smallblock Demon ran 9.90’s if I remember right

 

[33IMP]

Think his 500 inch smallblock Demon ran 9.90’s if I remember right

So did his 471. He went 6.47 thru mufflers against my 6.53 with his 471. We were both 6.20s-6.30s a little later.
He's lots faster now with his gen 3 demon.

 

[crackedback]

An acquaintance of mine ran a 471" sbm for several years. No durability problems that I know of. Nine second street driven 71 demon. The one pass heads up against him, I got to the finish line first..... but I had to redlight to do it, lol .
His 501 (or was it 502?) sbm didn't last. Too many too-light components.
The bigger the small block you build the bigger/better heads you need.
Don't put a 225cfm head on a 440 inch motor like Mopar did.

Ron always built clean stuff.

 

[Ottmundr]

Hello Guys, just found out that Eagle has got a forged SBM crank with 4.250" stroke length:

https://www.eaglerod.com/item/5674114-4340-crank-chry-360-4250-stroke?category=294327

Anybody did a stroker with this one and could supply the used parts / info about how much clearance work was necessary in a production block?

Running a 4" stroke at the moment, just thinking about future upgrades.

Michael

Building an engine for an L600 truck?

 

[33IMP]

Ron always built clean stuff.

The stainless bolt-together headers he built for his 71 were works of art. So was the rest of the car.
So was Silvaliant. That thing ran hard with an out of the box crate 360.

 

[Ottmundr]

Or, throw a 6 pack on it and call it an (L)A12
4.06 bore x 4.25 stroke = 440

 

[furrystump]

Just ask a friend who put one together. Not hard to get it to fit. He can’t remember if it was an Eagle crank(old as dirt) no reliability issues at all.

 

[rumblefish360]

The bigger the small block you build the bigger/better heads you need.
Don't put a 225cfm head on a 440 inch motor like Mopar did.

LMAO!

I will say that when the only head to port was the iron head with 300 or so cfm, the 440 would run really well. I don’t see an issue with a BIG stroker small block being much different despite what we know we are leaving on the table.

A very well ported W2/5 would make good power.
Though we know a W-7-8-9 or a Victor head would kill it.

 

[A body]

The stainless bolt-together headers he built for his 71 were works of art. So was the rest of the car.
So was Silvaliant. That thing ran hard with an out of the box crate 360.

I believe “Silvaliant” is in Havasu. East coast Mopar reached out about dropping in for a visit as he was flying out via Vegas to seal the deal. Seller backed out at the last minute

 

[usp4u]

I believe “Silvaliant” is in Havasu. East coast Mopar reached out about dropping in for a visit as he was flying out via Vegas to seal the deal. Seller backed out at the last minute

That was me, lol.
The car is owned by a guy in Rancho Cucamonga and is stored in Havasu.

 

[tvt59]

LMAO!

I will say that when the only head to port was the iron head with 300 or so cfm, the 440 would run really well. I don’t see an issue with a BIG stroker small block being much different despite what we know we are leaving on the table.

A very well ported W2/5 would make good power.
Though we know a W-7-8-9 or a Victor head would kill it.

Just think what a set of the P5 heads could do on a 4.25" stroke.....

 

[Bobzilla]

Just think what a set of the P5 heads could do on a 4.25" stroke.....

Pretty sure I saw an article saying Ritter is offering a version of his cast iron block to make that happen with P5 heads. Sounds pretty cool.

 

[tvt59]

Pretty sure I saw an article saying Ritter is offering a version of his cast iron block to make that happen with P5 heads. Sounds pretty cool.

Yes sir, Cast iron and aluminum both I think.