Pressure plate bolts...

[aarvig]

Question for the tech heads out there: I was assembling my engine and trans tonight and discovered that my 8mm pressure plate bolts from ARP do not thread into the flywheel. Upon doing some research I have discovered that some Ford flywheels have 5/16 threads. Does anyone know why? I am assuming this is why I am having issues as I don't have any 5/16 x 18 bolts to just thread in and see if they fit. Interesting as well, the flywheel dowel pins slid in by hand...I would have thought I needed to hammer them in. I have a 157 tooth 28oz internally balanced flywheel. Something isn't right, not sure if I have the wrong hardware or the wrong flywheel. Flywheel did bolt right onto the crank....

[edwardb]

SBF's I've worked on all had SAE flywheel and pressure plate bolts. Pretty typical for engines of that vintage. I would guess very likely the pressure plate bolts are 5/16 x 18. The dowel pins should be a very tight friction fit. I always freeze them and they still take some good raps to drive into place. Sliding in by hand isn't right.

[Bobby Doug]

I had an issue with my flywheel holes not being threaded all the way thru. I tried both metric and SAE bolts. It seems the cutting of the threads started on the block side of the flywheel and the person at the factory who was supposed to do the thread cutting only ran the tap till it showed on the pressure plate side. My engine builder said to check this by starting a bolt on the backside of the flywheel. I do not remember if the bolt holes are metric or SAE. I had to finish the cutting of the threads with a tap I purchased. You might try the same.

[aarvig]

I agree, I thought they should be tapped in with a hammer. Talking to the engine builder this morning he says this particular style of dowel is stepped and that the thicker end pushes into the flywheel by hand and the thinner end goes through the pressure plate. Once the pressure plate is bolted down it holds the dowel pins in position. Sounds logical but has anyone seen this before...I'm just used to tapping those dowels in.

[bobl]

I agree, I thought they should be tapped in with a hammer. Talking to the engine builder this morning he says this particular style of dowel is stepped and that the thicker end pushes into the flywheel by hand and the thinner end goes through the pressure plate. Once the pressure plate is bolted down it holds the dowel pins in position. Sounds logical but has anyone seen this before...I'm just used to tapping those dowels in.

Same here, just installed a Center Force dual friction clutch and the dowls were the same way.

[aarvig]

Same here, just installed a Center Force dual friction clutch and the dowls were the same way.

Bob, do you mean that your dowels were able to be installed with finger pressure...?