SBC engine question need help

I am building a stroker motor and i have installed the crank, rod and pistons.
When the ***embly rotates the pistons and the counter weights have zero tollerance. My question is will they stretch at all. It has been balanced.

 

Crank counterweights are real close to the piston skirts?

What kind of pistons, cast or forged?

 

I am using forged pistons, But i am talking touching the counter weight.

 

When the piston is all the way down in the bore, how much skirt is sticking out past the bottom of the cylinder block?

 

I am not sure off the top, But i will take a look at that. I am ***uming that at worst case it will just rub for a slight moment. i am not going to over rev at all just building a tire burner.
Thanks for the help

 

Sounds like a grenade in the offing.LOL
More details please.

 

Are you sure you have the right piston for the rod length you are using?

 

FIRE IN THE HOLE !!!-SOLO****KABOOOM***LOBO p.s. right, not going to rev it up much, just enough to fry the hides, thats like telling her your just going to stick it in a little bit. Just jivin ya bro, Good Luck!!

 

sounds like somebodys skirt is too long...no pun intended! Yep, if you are running 5.7 rods and a "stockish length" skirt on a stroker crank there will definately be contact. To answer your question if everything will stretch, yes, but not nearly enough to help your situation. Also, using the counterwieghts to "rub-off" the bottom of the skirt for clearance during intial start-up.... not the best of ideas.

 

Well ****! I better pull it all back down and figure this out. I dont want to launch this.
Thanks

 

how far down the bore are the pistons at tdc? If you have a 6.0 rod with a "5.7 piston" it should be above the deck a good amount. If you have a a 5.7 rod and a 6.0 piston, it should be down the bore a good amount. and if your right around deck height, then id say your skirts are too long. now, i am ***uming you are dropping a 3.75 crank into your 350 here?

 

maybe you have a set of 400 rods instead of 6" or 5.7 rods?I think the 400 rods are 5.65"??? Nothing should be "touching"in a rotating ***embly...even a little.Is the piston down in the bore when its at TDC? It should be at the top of the deck or real close.

 

Did you buy this as a rotating ***sembly or did you make it up out of mismatched parts? If the former, I'd get back with the supplierand get them involved with the answer as to how this happened. The supplier of a complete rotating ***embly SHOULD have this issue figured out and if there is a mixup on their part I'm certain they will be more than willing to correct the eror.

Frank

 

might wanna check to make sure you have the "right" pistons. most, but not all aftermarket 383 pistons have a shorter skirt and the pin height would also be different. 350 block, 400 crank, 350 or--late-- 327 rods, 383 pistons. if the shop "sold" you this set up and it is wrong, you might wanna double check other items?!?! brng. sizes, ring/bore sizes, balanced with correct flywheel/flexplate, harmonic balancer...etc. just an opinion...Ken


By the way...SELF CLEARANCE EQUALS SELF DESTRUCTION!!!!



ALSO...from another post....


"Try not to get many "chips" in the engine while grinding or filing on the piston skirts."


NOT BEING AN *** HERE< BUT.... Take the motor apart to find out the problem!!! 3 hours to pull apart and find the problem is LESS time and expense than to redo it all after that self clearancing destruction.... ASK any engine builder on here and I am sure they WILL AGREEEEEEE!!!!!!

 

If everything mentioned here about the piston being even with the cylinder head deck when at top-dead-center is okay....you might be able to remove a little bit of material from each piston skirt for clearance purposes.

Weight wise, it should be insignificant enough to affect balancing. Don't take anymore than you have to because the piston skirts are what keeps the piston from rocking in the bore.

Try not to get many "chips" in the engine while grinding or filing on the piston skirts.

 

I love it.
I once heard another guy talking about if it just touches a little bit it'll be okay it'll clearance itself just a few days before there was a hot rod layin on the track just past the burnout box.LMAO
You are really gonna have to give up some details for help here.
If ya don't know the details you need to find someone in your neighborhood who does to perform the laying on of hands etc to diffuse this bomb.


"Try not to get many "chips" in the engine while grinding or filing on the piston skirts"
Spoken like a true prodigy.ROFLMAO