8BA stroker kit

[3twinridges]

Machine shop called me this am to tell me the 4” crank I brought them was cracked on a main journal. Time for a stroker kit.

This is a stock engine, stock carb/ignition. How big of a stroke can I go with? I want to go with at least 4 1/8 stroke but would to go 4.25 if possible, thoughts?

JB

[3twinridges]

4” crank on the way. I just didn’t like having to bore this good block out to 3 5/16 for the 4 1/8 and 4 1/4 stroke. 4” is plenty

JB

[GB SISSON]

Good choice. Did you order a brand new 4" crank?

[3twinridges]

Originally Posted by GB SISSON

Good choice. Did you order a brand new 4" crank?

I did.

JB

[KiWinUS]

Just an FYI. you don’t need to bore block just because you install a 4 1/8” or 4 1/4” crankshaft. Either would have been a great addition and additional c.i.

[Tim Ayers]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by KiWinUS

Just an FYI. you don’t need to bore block just because you install a 4 1/8” or 4 1/4” crankshaft. Either would have been a great addition and additional c.i.

I was wondering the same. I think because the stroker kits usually come with pistons, rods, etc. as part of the "kit".

[38 coupe]

If anyone knows of affordable (same price or very close to 4" stroke) cast pistons for +0.060 or smaller overbore and a 4 1/8" stroke please let me know.
All the available 4 1/8" and 4 1/4" stroke pistons I find these days are +0.125 or larger over bore and many are forged. Unless building a hot rod engine these don't make sense to me. Given piston availability the 4" stroke crank makes sense to me.

[Tim Ayers]

Originally Posted by 38 coupe

If anyone knows of affordable (same price or very close to 4" stroke) cast pistons for +0.060 or smaller overbore and a 4 1/8" stroke please let me know.
All the available 4 1/8" and 4 1/4" stroke pistons I find these days are +0.125 or larger over bore and many are forged. Unless building a hot rod engine these don't make sense to me. Given piston availability the 4" stroke crank makes sense to me.

38 Coupe,

Have you called Egge? I'm pretty sure they'll do any size. Ross will as well, but I'd assume they would be out of your budget range judging by what you said in your post.

[3twinridges]

When I talked to H&H yesterday it seemed like a 4.125 stoke was not in the cards without a 5/16 bore. But I see a 4.125 scat with standard size rod journals and Ross makes a 4.125 stroke 60 over piston so not sure why that combo will not work with standard rods. I am going to call H&H this morning and dig around a little more.

JB

[Tim Ayers]

Originally Posted by 3twinridges

When I talked to H&H yesterday it seemed like a 4.125 stoke was not in the cards without a 5/16 bore. But I see a 4.125 scat with standard size rod journals and Ross makes a 4.125 stroke 60 over piston so not sure why that combo will not work with standard rods. I am going to call H&H this morning and dig around a little more.

JB

This went from being a stock build to a stroker motor real quick and I love it! LOL!

[tubman]

I would not build an 8BA without a 3 5/16 bore. I have done 3 of them and the machinist said they all would have gone more. ("OL' Ron" has mentioned 3 7/16"+ engines). To be fair, I did have to have one cylinder sleeved because of a casting flaw that caused a pit in the wall. The machinist said we could run it as is, but a sleeve would be good insurance.

The pistons cost about the same and like they say, "There is no replacement for displacement".

[Tim Ayers]

Originally Posted by tubman

I would not build an 8BA without a 3 5/16 bore. I have done 3 of them and the machinist said they all would have gone more. ("OL' Ron" has mentioned 3 7/16"+ engines). To be fair, I did have to have one cylinder sleeved because of a casting flaw that caused a pit in the wall. The machinist said we could run it as is, but a sleeve would be good insurance.

The pistons cost about the same and like they say, "There is no replacement for displacement".

Exactly!

[Bored&Stroked]

Yes - I would bore to 3 5/16 as well and if you're ordering a kit (depending on the rods you'll be using), I'd go to 4.125 or 4.250 stroke. There is nothing like the additional torque and cubic inches to bring a broader smile to your face! LOL

Here is the kit I'd order:

https://www.scatcrankshafts.com/product/1-94617bi/

[tubman]

These are not modern castings that are "done" at .060" over. Henry made 'em to last.

[3twinridges]

The problem with the 4.125 crank is the lead time on 4.125 60 over pistons. Well over 4 weeks to have them built. 4” 60 over are much more readily available.

JB

[19Fordy]

Gosh, I remember when I bought a complete 296 stroker kit with floating rod bearings and Jahn's pistons from Crankshaft Co. in CA in 1967 for about $500. Then it cost me a whopping $5 per hole to have it bored. My pay back then was $1.15 per hour. Took a lot of "saving up".

[Ggmac]

3twinridges , I sent you a email or pm , I forgot what I clicked on . Its about a motor I have that I’ll not be needing now . It sounds exactly like the one you want to build .
Gary

[3twinridges]

I am going stay with the 4”. Machine shop talked me out of a 4 1/8. They were afraid the extra stroke would put strain on the bearing caps and introduce more wear than a 4” for not much gain.

[3twinridges]

Originally Posted by Ggmac

3twinridges , I sent you a email or pm , I forgot what I clicked on . Its about a motor I have that I’ll not be needing now . It sounds exactly like the one you want to build .
Gary

Appreciate it but the purpose of the build is to introduce the kids to an iconic engine build. I want them to see one get put together and help me. Again appreciate the offer. Follow along as we have fun with it!

JB

[Tim Ayers]

Originally Posted by 3twinridges

I am going stay with the 4”. Machine shop talked me out of a 4 1/8. They were afraid the extra stroke would put strain on the bearing caps and introduce more wear than a 4” for not much gain.

For what you are looking to do, makes sense.

While you are in there, may I suggest cleaning up the exhaust and intake ports?

You can do this with sand paper rolls and a long arbor. The little effort/time it would take, it would make a difference and it will sound a little more like a hot rod flathead if you can get it to breathe better in & out.