Günther-C3

Hello!
After this season I will complete rebuild my motor. It is a L36 427/390hp. I have searched for stroker kits to 489ci or 496ci but all say, the starting point is a 454ci. Can I also stroke the 427 with the same kits? Can you recommend a kit (best bang for the bucks) and do I need internal balanced or external?

Thanks, Günther

ddawson

Yes you can, you just need to clearance the rod bolts.

See those little half cuts on each cylinder. They need to be larger.

ddawson

BTW I went internally balanced.

Günther-C3

Hmm, I already have these halft cuts

ddawson

When you install the new crank rod bolts will hit those areas. As you turn the crank you will see the bolts pass by.

I took my stock 427 and installed a 496 rotating assembly from Eagle.

Here is a good thread with pictures.
http://www.yellowbullet.com/forum/sh...d.php?t=465190

cardo0

Well i really dont know dirt about BB's but a trick i proposed to use for stroking small blocks may work. Just measure the clearance from the block/pan rail u have now. Add half the increase in stroke - i.e. from 4" stroke to 4.25" stroke would be = 0.125". Then find a wire or tube with this dimension (current clearance + 1/2 new stroke increase) and use it as a gauge to carve a large enough clearance for the new stroke using current crank and rod before the new crank arrives so you can clean the block. BTW u would still need to verify w/new crank.

Just my 2 cents worth.

CanadaGrant

The later 427 blocks from 69 were used in both the 69 427 L36 and the 70 454's. The casting number for both blocks (same) was 3963512 so it shouldn't be much of a problem to convert. You can go internally or externally balanced depending on what parts you want to use.

Danish Shark

Hi Günther

Just curious, why do you want to do this? Do you want more power or is it just because building a 427 is too expensive?

In my case it was the latter so I got a complete kit for 4.25 stroke.
It's not a problem building it but there are some issues, like the oil pan.
You need a bigger oil pan an then put a smaller amount of oil in that because of the larger crank.

Only 5 liters of oil in an engine that large just doesn't sit well with me.

/Karsten

gkull

No you buy 7-8 quart pans. You have to know your bore size and then you buy a 4.250 stroker internally balanced rotating kit. You might end up with a 489 ci

http://www.roadsters.com/bbc/#bore

http://www.callies.com/components/rotating-assemblies/

CA-Legal-Vette

I'd be curious about this as well. I've always wondered why 427 parts seem to be so expensive. Is it just lack of demand?

gkull

The reason is: GM quit manufacturing 427's 46 years ago. They opted for 454 as the big block installed in everything up to the modern era. Kind of like the smaller small blocks when the 350 came out.

dmaxx3500

ive got a 572'' BBC just off the dyno ,ready to put in your car,with aluminum heads,holley carb,roller cam

CA-Legal-Vette

I suppose that makes sense, for the OEM stuff at least. The same lack of availability seems to occur for the aftermarket stuff too. A 427 crank will be hundreds more than a 454 crank. I doubt that internal balancing would account for it.

L88Plus

Bought a Scat 3.766" 4340 crank this year with center counterweights, around $700, same price as the 4.00" and 4.25" stroke cranks. CNC piston manufacturing lets 'em move anything anywhere, so those aren't an issue any more. I'm planning to run a 6.700" Scat rod in mine with a 1.200 pin height piston. $80 for the first change to a piston and once that's paid, you can move pin, change diameter, valve pockets, chamber shape, you name it.

PAmotorman

do not rind too far or you will be into the main oil gallery along the pan rail.

Danish Shark

Are you saying you can buy custom pistons for only 80$ extra??? Or how to understand that?

MotorHead

You should be able to find a crank, rods and pistons for your 427ci pretty easy just look around the net.

L88Plus

Danish Shark, that's correct. When I go through my supplier at Scoggin-Dickey for Diamond pistons, I can order custom for only $80 more. Once you've made a change, the rest of the changes are free. Bore on my block is 4.632, so I'll get custom diameter and custom pin height (there are none at 1.200). I have the Bowtie heads that are approved for Super Stock and they have a unique chamber. Diamond has a line of pistons with domes for that chamber shape, so that'll be the starting point.
I learned about this while hanging out at a performance engine shop. If an engine was torn down for freshening and needed to be honed, sometimes it took the bores too large for recommended piston-to-cylinder tolerance. Instead of wasting cylinder wall material by boring it to the next shelf piston size, they honed the worst of the bores to new size and ordered pistons from there.
Ain't technology cool???

dmaxx3500

I remember '' world products made 5''x5'' bore/stroke blocks,heads,and they would go to 700-800ci'',a 10.0 comp eng made 900hp+

should bolt right in