Greetings to all, well, I'll be ready to hone my cylinders soon. Everyone with whom I've spoken says it's advantageous to use a torque plate. Problem is, neareast one to me (that I know of) is about 700 miles away, and they are very heavy ($) to ship. And really, don't you need two of them to really do the job right? Many shops that even have one, just have one, not two. We all know that there will be some shifting of the cylinders when heads are bolted one. Some blocks may shift a lot, others hardly at all. I'm using the meatier 1976 block, so perhaps mine won't shift as much as an earlier block. What if I measured the cylinders and then bolted on the cylinder heads. Then, I could measure the cylinders from underneath. Would it not be possible to get a pretty good idea of how much distortion is now present with the heads torqued on? In this regard, if distortion were minimal, I would feel pretty good about not using the torque plate. Any thoughts? Craig Stangohr/Aiken, S.C.
Craig, Are you honing the bores to clean up the originals and use stock size pistons, or are you having a machine shop bore the cylinders oversize (i.e. .030 over) which will be used with new pistons?
poor-man's torque plate Steve, the block was bored .030" about 25K miles ago. Ran .005" clearance then cuz I used forged pistons. I would like to use the .038" Wiesco flat tops, and the machinest thinks cylinders can be cleaned up and made round for the 4.350 bore size needed to use those pistons, also with .005" clearance. Any thoughts? --Craig Stangohr/Aiken, S.C.
I don't know much about this. I am not a machinist. I always figured that the distortion you were trying to correct by using a Torque Plate is that the cylinder bores expand slightly out of round around the bolt holes when the heads are torqued. I suppose you could attempt to measure the degree of distortion from underneath, and you'd have a heck of a time getting accurate measurements doing it too. Even if you had the measurements, there's no way you could accurately bore to correct that without a torque plate. All of that having been said, how hard would it be to make your own torque plate? I should think with some 2" plate and a head gasket to use as a template, your shop could probably fab up a low-cost adequate substitute. - Freed
I had the same thing done to my block. The machine shop i use ,Used the torque plate and he said it took him two days to hone the cylinders I don't remember why it might of been do to the block getting warm.
Actually this is in my opinion the best way to do it. It does take forever to do, granted, and the math involved can become overwhelming. You have to be very careful and take your time. If you use a torque plate that is about the best we can get. BUT, I have done this both ways(w/t-plate and the head/math route) and the torque plate measurements ARE different than with the head itself bolted on. Hone it with a plate and then bolt the head on, measure from the bottom, and see for yourself. The reading on the dial bore gauge WILL be different. I had a customer when I was machining in Tx. actually request I do this on a pair of ford engines for a race boat. Talk about a nightmare, it was. But in the end he was happy. If I were you, and these where your 2 options, I would buck the freight and use the torque plate. The time involved to measure from the bottom and hone it, then repeat, will kill you on the final price. There is surely someone closer, that your machine shop could borrow or rent one from. When I was learning about this stuff thats what I did, borrowed from the Conleys in Houston actually. Anyways.......I would say look around some more and see if you can locate a plate. Anyone that can run a hone will have you done in an hour(2 tops) pending amount left to hone. Anymore than that and your getting taken to the cleaners. later........................
one or two torque plates? Well, anyone know who has a torque plate to rent? Actually, do we need two of them? I'm sure I read that Finish Line uses two when they do the job. Or, could we get by with just one, bolting a cylinder head to the opposite side? Regards, Craig Stangohr/Aiken, S.C.
