426 cleveland stroker

bounty 1 · #1 (**permalink**) 07-05-2009, 10:00 AM

1st cleveland and love it. any word on stroked 426 clevelands? need some feedback by Ford guys and not sales people. Thanks

1985 CCX · #2 (**permalink**) 07-05-2009, 11:04 AM

Sounds cool? Reliable?

Mark O'Neal · #3 (**permalink**) 07-09-2009, 10:45 PM

Quote:

Originally Posted by bounty 1

1st cleveland and love it. any word on stroked 426 clevelands? need some feedback by Ford guys and not sales people. Thanks

I assume you're referring to a 9.500 block?

The more motor you give a Cleveland head the better it likes it.

blykins · #4 (**permalink**) 07-10-2009, 04:20 AM

I don't think you can get there with a 9.200" block, and if you could, I wouldn't recommend it. Clevelands are not known for thick cylinder wall thicknesses. That much of a stroke would put a lot of side loading on the walls.

A lot of builders don't even like to go to 408 with Cleveland blocks.

Shadetree · #5 (**permalink**) 07-12-2009, 03:30 PM

Bounty 1,

I run Clevelands in my Pantera's and am just finishing up a 408 stroker. That's about as large as you can make a cleveland because of the deck height and wall thickness. If you're running the early 4V closed chamber heads with that combo you should be able to get 500 + horsepower and torque out of a 10.5 compression engine with right cam and a little head work.

If you need more cubes you're going to have to go to a Windsor or Clevor block like the Dart. You can take the 9.5 deck height Dart all the way to 454 cubes.

Jac Mac · #6 (**permalink**) 07-12-2009, 06:25 PM

Short of finding one of the 'Rare' Siamese blocks designated for Nascar in the mid/late 70's that were cast in the USA then shipped to Aussie for machineing etc its a 'Risky Business' Im even more conservative than these guys when it comes to the production blocks, wont bore them past 4.030", wont build them with less than a 6" rod even at 3.5" stroke. Why, I learnt the hard way---- the more you stroke em the more they broke em'

& I hate doing things twice for no good reason.

LoBelly · #7 (**permalink**) 07-12-2009, 07:57 PM

I think maybe its a reference to the new Boss351 block

http://www.autoblog.com/2009/06/13/f...-engine-block/

available in 9.2 & 9.5 deck height

from the article...
"Max stroke is up to 4.25" depending on crankshaft manufacturer with max bore size topping out at 4.125" with coolant cross drilling. A non cross-drilled block with increased bore capacity will be available by 3rd quarter."

guessing this would get you a 4.00 x 4.125 in a 9.2in block (?)

LoBelly

767Jockey · #8 (**permalink**) 07-12-2009, 08:09 PM

Go over to the Cleveland forum, there's a guy named Tod Buttermore who has developed a new Cleveland block with an much improved main priority oiling system. It's supposed to accomodate significantly larger bore and stroke parameters than a standard Cleveland block, and it's available in both iron and aluminum.

Shadetree · #9 (**permalink**) 07-13-2009, 10:09 PM

Tod's block isn't ready yet but will have better oiling and the ability to go with a bigger bore but still has the 9.2 Cleveland deck height. The Boss 351 block is similar to the Dart World Style block and a bunch of Dart copies now coming in from China that are basically Windsor blocks with the Cleveland 2.75 main bearings and 4 bolt main bearing caps.

PANAVIA · #10 (**permalink**) 07-19-2009, 02:01 AM

Shade Tree--

your comment "Dart copies now coming in from China " -- what have you seen >? are they showing up as off brands or are they trying to sell them as Dart/SVO/etc >?

--Steve

Mark O'Neal · #11 (**permalink**) 07-19-2009, 03:25 PM

Quote:

Originally Posted by PANAVIA

Shade Tree--

your comment "Dart copies now coming in from China " -- what have you seen >? are they showing up as off brands or are they trying to sell them as Dart/SVO/etc >?

--Steve

It looks just like a Dart Iron Eagle...Dick has stopped anyone from selling them, last I heard.

PANAVIA · #12 (**permalink**) 07-19-2009, 11:16 PM

There was a book out by George Reid that explained stroked small blocks, and there was some Cleavland info therein. I think there was a 426 possible with a 9.2" deck if memory serves.

http://www.amazon.com/Build-Big-Inch.../dp/1884089836

Mark O'Neal · #13 (**permalink**) 07-20-2009, 10:13 AM

Quote:

Originally Posted by PANAVIA

There was a book out by George Reid that explained stroked small blocks, and there was some Cleavland info therein. I think there was a 426 possible with a 9.2" deck if memory serves.

http://www.amazon.com/Build-Big-Inch.../dp/1884089836

You could do it.

But you'd wake up screaming in a puddle of cold sweat for months afterward.

cobrarkc · #14 (**permalink**) 07-20-2009, 11:22 AM

Here is the only company making this kit and I hear that their quality is questionable.
http://www.speedomotive.com/ps-127-1...roker-kit.aspx
After speaking with many Cleveland builders no one recommends going over 4" stroke. Keith Craft only recommends 393's.
Tod Buttermore will also be producing a 9.5" deck block at some point which should get you 460ci, pair that up with some nice CHI heads and you should easily make 700hp. A 408 will get you over 600hp with these heads.

Mark O'Neal · #15 (**permalink**) 07-20-2009, 10:37 PM

Me, I'm with Keith.

racingrick · #16 (**permalink**) 07-21-2009, 02:32 PM

What is the problem? Are the cylinder walls cracking at a 4.0" or 4.1" stroke?

The piston compression height is shorter in a 347 than a 426 Cleveland would be.

Jac Mac · #17 (**permalink**) 07-21-2009, 03:04 PM

Apart from the std clevo cyl wall thickness problem its stroke & rod ratio( and the resulting angle), not pin height that are the real issue.
On the 3.4" stroke / 5.4 rod this ratio is 1.588/1 with the 302 8.200" block.

Clevo with 4" stroke/6.125" rod is 1.531/1 in 9.2" block with 1.075 pin height.

racingrick · #18 (**permalink**) 07-21-2009, 03:17 PM

I see a lot of 4.0" stroke with 6.0" rods in 408 Clevelands (1.5 ratio).

A 426C with a 4.1" stroke and 6.0" rods is 1.46 ratio.

Does piston speed also play a role in the destruction of Cleveland cylinder walls?

jdean · #19 (**permalink**) 07-21-2009, 03:49 PM

Yeah around 1.5 ratio is about the same as a stock BBC 454 which has 1.53....the bowtie bunch dont complain much....and they push a lot of power with them.

Jac Mac · #20 (**permalink**) 07-21-2009, 04:08 PM

Quote:

Originally Posted by racingrick

I see a lot of 4.0" stroke with 6.0" rods in 408 Clevelands (1.5 ratio).

A 426C with a 4.1" stroke and 6.0" rods is 1.46 ratio.

Does piston speed also play a role in the destruction of Cleveland cylinder walls?

Its kinda hard to isolate piston speed, it comes with the territory in longer strokes & if the owner insists on pushing the RPM it does become a major factor. Depends on what the application is really, Put it in a class where the high RPM is not continous & the stroker will probably last, try it in a boat or circuit car ( Road course or Nascar long track types ) where high revs are for longer periods and the short rod combo will self distruct.

The best example that we probably have here is the SBF combos of: 4.125 bore X 3.25" stroke versus the 4.00" bore by 3.40" stroke. Both are the same capacity @ around 346/347 ci, but the short stroke/big bore motor can rev higher, yet really gives nothing away down low either.

Clevos are pretty popular down under with the Aussie Falcon crowd & an easy swap to a 6" rod ( The 302c had a 6" rod/3.00" stroke ) plus an Aussie 1.425" pin height piston makes a nicer motor out of the 351c & virtually eliminates the bore cracking problem.

One other problem the std 351c has, the std rod/piston combo pulls the piston skirt well below the cyl bore @ BDC, the 6" rod cures that, but it returns again if you lengthen the stroke, on the Jet Boats we worked with that ran continous @ around 5500 plus the piston skirt would get a very defined 'mark' on the skirt where the piston 'rocked' @ BDC largely due to the lack of bore support.