I've told this several times before so will go through it again to help keep you from making the same mistake I did.
I bought Lunati's, (probably last), 4.25" welded crank AND totally missed the part where the guy said, "oh, by the way, you need to run 1/4" longer rods with our crank so hopefully you won't need any Heavi-metal to balance it"!!
Anyway, I bought a set of 9.5 to 1CR. ROSS 496 stroker pistons that fit the good stock truck rods I am using thinking that everything was cool until I bolted the sucker together AND it locked up at BDC b/c the pin boss was jambing against the crank counterweights!!
I had FLAT forgotten about the extra 1/8" needed at BDC but thought the stroker piston took care of it b/c it didn't stick out the top the other 1/8"...
What really pissed me off was that a local Machine Shop that I got to balance the rotating assembly DIDN'T tell me it locked up AND I WILL bet you a dollar to a donut hole the father of the shop knew it BEFORE they balanced it!!
I put it together it locked up, I took it back and the SON said, no problem, I will get DAD to cam-cut the cranks counterweights after I called Lunati AND asked them what to do!!
Needless to say, my stuff sat for three weeks before I went to the shop and asked why they weren't fixing my problem? The SON said, that DAD didn't want to do it and he didn't call me like they didn't the first goaround!! AND I NEVER got upset at all and was very willing to pay my money until I found out they backed out AND didn't tell up front!!
The SON overloaded DADDY'S dear old As- and DADDY backed out!!
I gathered up my stuff, called Lunati and made an appointment to get the crank fixed along with the needed previously balanced "Bob-weight". Next took a days vacation and drove down to Memphis, dropped the stuff off and drove back while coming from B'ham, AL where I visited my buddy and picked it all up and was done with my MISTAKE!!!
And the cost of all this at that time was not quite what a set of hi-po, 1/4" longer rods would have cost b/c this was before everybody AND their brother started making/selling longer cheap BB rods!!
Everything worked out fine but I learned a good lesson!! And the cost wasn't all that outta line but now I know I can build another 496 or bigger cheaper then the $3800 to $4000 I have in mine, including new cast-iron, Merlin ovals!!
Please read this carefully AND let it soak in what I went through to save you the same hassle..
As always, just pdq67