5.3 all day long

 

Yep, the longer crank eliminates the need for the crank spacer on the later ones... just make sure you use the flat flexplate!

 

I need to invest in a dremel tool so I can round out the bolt holes for my sbc converter.

 

Shouldn't be but 1/4" or so that you need to open the holes up to match the th350's pattern right? Ive got my flexplate, spacer, and verter sitting in the garage, just been to lazy to test fit to see how much needs to be removed!

 

Id take the 5.3..

 

Well too late Nonnie, I have the old 6.0 and it will be sitting in as soon as I tackle my converter issue.

 

OK ...just throwing this out there since I've never dealt with this particular situation ....

We all agree that you can use either the long crank with the flat flex plate or the short crankshaft with the spacer and flat flex plate and mount either configuration to a 700R4, TH350 or TH400 by simply elongation your holes for the convertor. Why can you use this same configuration with the 4L60E? The flat flex plate and spacer position the flex plate ring gear the same as the dished 4L60E style flex plate so why can't use the flat flex plate with the 4L60E and simply elongate the holes to fit the convertor bolt pattern?

 

It all has to do with the pilot length. The th350 coverter has a shorter pilot so the spacer or longer crank is required to support the center of the torque converter. Thats why you can remove the spacer and run a dished flexplate to run a 4l60e, but you're out of luck with the longer crank.

 

You're absolutely right!! I knew all that, but I still didn't realize it. Thanks for the insight!!!

 

If you insist on running a 4l60e you can have a custom TC made with a machined snout. Not worth the hassle since the 4l80e is stronger and the TH400 is cheaper.

Now what are people using to elongate the holes in the flexplate? Do I need to go borrow my neighbors dremel?