Pilot Bearing Bore Diameter on SCAT 4.25" Crankshafts

[Wreckless Warren]

I ordered a new C-6 & convertor for the 445 in the red 65, from Paul at TurboAction Transmissions in Jacksonville Fl.(same folks who build the shifters). It has a blown TCI StreetFighter C-6/Convertor in it now.

After giving him all my build specs and he wanted to be sure of the diameter of the pilot hole in the back of the SCAT stroker crank (over the years there has been issues dealing with aftermarket cranks and that dimension}. He asked me to measure it but the old trans is still in.

So I tried to measure the SCAT 4.25 crank in my current 445 build with my calipers but it's hard to get a good angle with the stand in the way. My reading went from 1.831" to 1.845".

Paul says it should be 1.850 +/- .003". I called SCAT, they say it has two pilot holes, one 1.375" and one 1.845".

I know the 445 crank in the car now accepts the TCI 10" convertor connected to it successfully but I don't know what the diameter of the snout on that convertor is.

If I understand Paul correctly, his convertors require a close tollerance between the snout of the convertor and the pilot hole in the crank so that is what's centering the convertor to the crank and not the mounting points.

Please help shed some light on this. What have you measured on these cranks and what issues, if any, have you had mounting torque convertors to them? You input is greatly appreciated. ww


http://i226.photobucket.com/albums/dd31/65cobrajet428/390-445%20Build/crank_pilot_hole_spec005c2_zps269a9e21.jpg

[jayb]

Seems like every time I put together a motor I'm fighting with the same issue.  The last Scat crank I did measured 1.848" ID.  I think in all cases with aftermarket converters they rely on the pilot hole in the crank to center the converter, not the bolt circle on the flywheel.  I'd have him do it big, like 1.850", and then have it turned down to fit if necessary once you get the trans out and can take a reliable measurement.

[Wreckless Warren]

I borrowed a set of telescoping gauges to get an accurate measurement of the pilot bearing hole. It's 1.847". That's within the 1.850" +/- .003" he specified.  The new trans & convertor are suppose to be ready this week. I sure hope it goes in with no drama. I'll post the results when I have them. ww