Hey guys. I have built many bbc's, but this is my first 496 stroker build. I am using a forged 4340 Scat crank with 4.250 stroke and Scat h-beam 6.385 connecting rods along with a gm 4 bolt 454 block. I also am using a Moroso pan that is good to 4.500 stroke. I am pretty sure that i don't need to clearance the block for the extra .250 stroke, but wanted to see if any you guys that built one of these ran into the need to clearance. Thanks

You knew this was coming...

It will probably fit fine, but you should check anyway!

I'm just about to assembly my 489. It's a '74 454 block with the same size Eagle crank and rods. Everything fit fine and I had plenty of clearance.

If you can, you should really check it though. Just lay down the bearings on the mains, drop in the crank and just use one piston/rod combo and install it in each cylinder. Took me 20 minutes...

Jason

we haven't had to clearance any of the ones we have built yet at the machine shop where I work.

Definitely check the clearance, cheap peace of mind. I had to clearance my block for my 489 some of the clearances were pretty tight (was looking for at least 060 clearance).

As said, you should check for peace of mind.

It will just cost you your time..... instead of a motor!

I would have nightmares wondering!

Good luck!

I always check all clearances. I just wanted to know what you guys have ran into on the bbc stroker builds. Hopefully it needs no clearancing, we will see. This should be a reliable and potent piece.:D

Use a 12" long piece of 1/8" dia. plumber's copper pipe soder wire as a pinch-point checker!

And I figure my '75 "TSC" code P/U block may take a 4.375" crank w/ very little rework, there's that much room around my 496 rotating assembly.

pdq67

Use a 12" long piece of 1/8" dia. plumber's copper pipe soder wire as a pinch-point checker!

And I figure my '75 "TSC" code P/U block may take a 4.375" crank w/ very little rework, there's that much room around my 496 rotating assembly.

pdq67


Good to hear pdq. Thanks:thumbsup:

6.535 rods a must

I had to clearence the block at the bottom of the bores in the 496 I built for a friend. didnt need much grinding, but it still needed it. 4 seperate places. I used capscrew 6.385 rods, and the rods are what made contact.
I am confident I could fit the 4.375 stroker in there w/ a tiny bit more grinding.

The last two I built both required clearancing at the bottom of the bores next to the cam tunnel. Next to the pan rails was fine.

One was a SCAT crank and Manley H-beam rods in a `73 passenger car block and the other was an Eagle crank and SCAT H-beam rods in a `77 pickup truck block.

Neither would rotate w/o clearancing.

http://www.vintagemusclecarparts.com/496/A27_Clearance_for_rods.jpg

Eric

Definitely check the clearance, cheap peace of mind. I had to clearance my block for my 489 some of the clearances were pretty tight (was looking for at least 060 clearance).
Same here, had to clearance my block too.

Back again, "truck rods" here and I had to cam-cut the crank b/c of piston pin boss/crank counterweight lock-up!

Long story, but everything turned out fine in the end.

pdq67

Hey guys. I have built many bbc's, but this is my first 496 stroker build. I am using a forged 4340 Scat crank with 4.250 stroke and Scat h-beam 6.385 connecting rods along with a gm 4 bolt 454 block. I also am using a Moroso pan that is good to 4.500 stroke. I am pretty sure that i don't need to clearance the block for the extra .250 stroke, but wanted to see if any you guys that built one of these ran into the need to clearance. Thanks


Doug,

I see our 45 minute phone conversation meant nothing to you ????? Call your buddy Ray where you bought the block from. Maybe he will tell you what you want to hear!!!!!

Ron 92Camaro :beers:

Doug,

I see our 45 minute phone conversation meant nothing to you ????? Call your buddy Ray where you bought the block from. Maybe he will tell you what you want to hear!!!!!

Ron 92Camaro :beers:


Ron. I don't believe we spoke about clearance for the stroker kit.:confused: I bought the block from Ray's, that does not mean they are my buddies.:confused: Not sure if i sense a bit of attitude and why there would be any for that matter. The phone call i made to you was about your headers, not advice. I started this thread to see what others have ran into. I listen to all opinions, doesn't mean i will take the advice offered! I have built many cars and every one of them far exceeded expectations for et! I know you have built a few 496's and sorry if you think i was ignoring something that you said. By the way, i didn't buy your headers because i thought it best to buy a 2 inch primary header. I am not building this to drag race all the time, mostly it will be a weekend cruiser with occasional strip time. Sorry if i offended you in some way. Doug