I'm about to get my 464 engine balanced. The combo is as follows. Indexed crank, late one without the "N". Romac balancer, conical SRP pistons, TA Sportsman rods, SFI flexplate. Should I do anything to any of these parts before having the balancing done? Or should I let the person who is doing the balancing know anything about the rotating assembly that might make it easier to do? Or is it a straight forward procedure? Any replies will be greatly appreciated.
Looks like a standard balance job to me. I haven't worked with the sportsman rods, they may or may not need work but should be weighed unless they come with weight card. The SRP pistons should not need work but should be checked. Get the bob weight used for future reference and file it somewhere. I like to scribe the bob weight on the crank counterweight. Remeber to take your rings and a rod bearing for the weights.
Thanks for the info Dennis. FYI the card with the rods says Rotate Wt. 546, Recip. Wt. 238, Total Wt. 784. The card for the pistons says 688. I'll have them all weighed JIC.:TU:
Looks like I will need 4 grams off the front of the crank and 75 grams added to the back. Of course the machinist never worked on a Buick before. He said 75 grams is a little extreme. I just read if the crank is out 1oz. At 5000 rpm it will seem like there is a 44lb weight swinging on it. Is this amount of added weight common with this type of assembly or is there nothing to worry about? Any feedback would be appreciated. : o No:
The culprit for the need for Mallory metal is most likely the SFI flexplate. Have your machinst balance the assembly with a stock plate, then remove weight from the SFI plate to get it back in balance. This is typical, I have yet to see one of those SFI flexplates be consistant in the weight placement. I actually did two on one assembly once, and the two new plates were not the same, on the same assembly that was balanced with a stock plate. I have done 5 or 6 motors now with those pistons and rods, and don't recall having to add any mallory metal to a crank yet. Only thing we typically have to add weight to is the stroker stuff. Not saying that he may not have to add a little heavy metal to your particular assembly, but I do believe going with a stock plate first, and then matching the SFI plate to the assembly that is balanced with the stock plate is the way to go. It's not uncommon for me to see 4-6 3/4 drill points in one of those SFI flexplates. JW
Thanks Jim. I thought it might have had something to do with the flexplate. Just wasn't sure. I never had anything balanced before. BTW it is a "JW" flexplate 4yrs. old with the lightening holes purchased from Torque Tech. JIC you run into one. A big thanks!! Now I know what is going on. :TU:
Are we talking internal or external balance? I've always had to add a fair amount of mallory even with stock flexplate with internal balance. Jim, you've done some with no added mallory? Bruce
External Balance, Bruce.. Billet crank motors get internal balanced, but that's all.. Never seen the advantage of spending the $$ to internal balance anything less than a Big $$ race motor. And the less Mallory you can get away with, the better off you are.. ask Rick Martinez why.. JW
Mine is internal with weights welded.....could be money well spent if it helps the block and crank live....cost was $550 vs $250 for external. Would like to minimize the amount of weight added though....alum rods would help, right? Bruce
