I am rebuilding my 4L80E, using Alto Red Eagle clutches and Kolene frictions, however, I cam across a statement that Kevlar or kevlar relined bands are not recommended for street cars. Any opinions?

 

When building on of these units, use the Borg Warner Hi-Energy clutches for 2nd gear, 3rd gear (not the Alto Reds), & the 2nd gear band (the late extra wide band, it is Hi-Energy also). Increase the clutch count for third by using a direct drum from an early Cadillac (1965-1971). The Kolene steels are fine, make sure you take 1,000-1,600 grit and polish all the Kolene steels in the direction of rotation (Alto approves of this by the way) to remove the roughness of the surface, the smoother the better. I would use the Trans-Go Performance Shift kit setup. Do not block any of the accumulators, work with them. Use the turbulator (low drag) steels in the overdrive & overrun areas. The stock OEM low/reverse band works best. Use the solid teflon rings on the stator & center support and cast iron rings on the accumulators. Install the "orange" spring in the low/reverse band apply area, this helps with the 1-2 shift. The fluid to use here should be high quality. For synthetic, use the Amsoil or Redline, for non-synthetic use Mobil or Aamco dexron III for "best" results. This should give you a good start at things. In answer to your question on Kevlar Bands, NO!

 

I was searching for info on building the 700r4 and came across this one. I just wanted to find out why the big NO for using the kevlar band?

 

The Kevlar band has less holding power & generates more heat. Yes, it can handle more heat, but it creates more. They do not last as long as the stock band in most cases. The Borg Warner Hi-Energy band has a little Kevlar in it, but not enough to create any problems. The BW Hi-E 2-4 band is what I have found to work the best in all applications.