Wanting to do a stroker. Advice?

Any recommendations for companies who do weldup and offset grinding? Does anyone actually do real welding on cranks any more? A big name local engine builder here does spray welding and I've been told it is a lot softer.

What about custom grinds from scratch?

 

It would help if we knew what engine you are doing.

 

It's a 430 Lincoln engine. Also, what is a 3/4" stroker? What does that refer to?

 

ttt

 

What is your goal with this engine. 430 is alot of cubes to start with.

 

Depending on bore size some of those Ford parts interchange. For example a 428 crank in 427 block makes a 454 Ford.

 

Say, for example, that a crank's given stock stroke is 4"....a 3/4" stroker crank would be one that increases it to 4 3/4". Imagine a line drawn through the center of the main journals, and then another parallel line drawn through the center of a rod throw. For our example, the lines would be 2" apart in stock form, and 2 3/8" in stroker form.

Now, keep in mind that it refers to "total" stroke length, both at the top and bottom...so the crank itself is actually only getting 3/8" material added to the outside of the rod journal throws, and, theoretically, getting 3/8" removed from the "inside", if you wanted to use the stock bearing sizes.

A lot of this depends on how the oil passages are drilled in the crank. You can only move stuff around so much before you hit an oil passage; in addition, you have to worry about the big ends of the rods hitting the camshaft, block, oil pan, etc. You also have to think about available connecting rods with the right journal bore size and the right length. Of course you can always have custom rods made...but it's not much fun paying for custom pistons, cranks, AND rods.

Another way to stroke a crank is by "offset grinding". Here, the machinist reduces the size of the rod journal, taking off much more on the inside than the outside, and connecting rods with smaller bearing sizes are used. One example would be the Ford 460, with a 3.85" stroke; commonly, the crank is offset ground to a max of 4.14", and rods with the smaller BB Chevrolet rod journal size are used. The advantage here is that no welding is needed. However, as a very general rule, you can't get as much additional stroke as you can with welding.

I can give you the names of a couple of good places to do either method. As you probably have surmised, it is not cheap (though offset grinding is much less expensive than a true welded crank); and it typically takes a while to get the crank back.

A true custom crank made from scratch will cost very much in excess of $2000...probably close to $3000...and that's not doing anything really exotic in terms of materials or machining, just a basic crank. You have to ask yourself at that point whether the gains are worth the expense.

Other things to consider are available cylinder head flow vs. displacement. I think it possible that you might be better off starting with a 462 block, boring it as much as possible (sonic tested, of course), and offset grinding a 462 crank with its already .130 longer stroke...then using the better early 430 heads. The disadvantage here is the 462's weird trans pattern.

 

447 at std bore and 454 @ .030

How about just dropping in the 462 crank and boring it .060 to a stock 460 bore size. That would give you 457.5 cubes. Offset grinding the crank .020 would give you the 460 cubes but then brgs etc may be a real issue.



Or a Bore & Stroke of 4.360 x 3.830 = 457.5 Cubes

For the cost its just not worth the mega cube $$ to gain so little unless you are going to do some serious head work.

Do you happen to have one of the Ultra Rare Super Marauder engines?

Why are you stuck on doing a 430?

Cranks on the 430 & 462 are 2.6 R & 2.9 M

 

I have a 59 engine that uses the FE bell pattern. I'm going to run a 4 spd. I'm going to have the block sonic checked to see how far it can be overbored.

 

Hank the Crank, phone # is 562-861-7682

 

Back when those things were new people ran a few of them in dragsters at 508 cid. I would assume the crank was ground offset to use SBC or similar bearings. The obvious thought is the 472 version. I recently had a four throw billet 4340 crank made at Crower and it was around $2600. But you get to have the flywheel flange made to accept a 460 or other flywheel of your choice as well as the dampener/snout. Helps when you are looking for the rest of the parts. You could use BBC throw dias. and BBC rods and bearings. Saves a few bucks down the road.

 

Thank you very much...that was someone I thought long out of business.

 

Thanks 'warp. I forgot about the .030 over. I helped build one of those many years ago.