I have a 1970 Skylark with a TH350 and a 455. Previous owner installed a TransGo Shift Kit. The shifts are OK, but I would like to make them slightly higher (in RPM) and more firm. I did as search here (lots of info) and noticed that you could drill out certain holes in the Valve Body Plate to make shifts more firm. I have no instructions to look at but I would like to check and perhaps inlarge these hole to make my shift feel more firm. Should I just purchase another kit from Summit or Jegs, or does anyone have the instructions available? Thanks in advance, Brandon jbrandon3@yahoo.com
get a turbo 400. much better suited for a 455. All you have to do for it is modify goverrnor weights. I never tried to mod a 350
Keep your TH350 since it is working condition. You have to be careful what you do as far as making the 1-2 shift overly firm. I can guide you through it and make it shift firmer without breaking stuff and you won't need to buy another kit.
Jakeshoe, Can you give me some info soon? I would like to make these adjustments over the weekend if possible. Brandon
Brandon, Yes. I forget that I don't have any contact info listed here. Anyway, http://www.nastyz28.com/forum/showthread.php?t=53671 This thread will cover alot of what you need to know/do. This picture will show you which holes to drill to firm up the shifts further. Don't drill the 1-2 hole over .140" in any circumstance, I usually drill to .125" especially if the trans has the stock roller clutch setup internally. The 3rd feed will work well at .140". You can also take apart the 2-3 accumulator in the valve body, remove the spring, and use a piece of tubing or washers/nut. Remove spring, re-install piston, then shim the piston so it can't move, and then re-install the e-clip on the pin. Or you can block the hole in the plate that feeds the back of the piston. Aluminum welding rod of the correct diameter can be used if using that method. Jake
jakeshoe, Could you give me a little more info on the 2-3 accumulator mod. I have seen one on my 2004R when I added a shift kit to it, but I'm not sure exactly what to do to the TH350. The 2004R required new springs - which I had no problem changing. I just need more help on the washer/nut or rubber hose thing (explain how to shim up the accum). Thanks for all of the help. Brandon
No rubber hose. You remove the e-clip, then the piston, then the spring behind the piston. Put the piston back in the valve body. Stack washers, a nut, or a piece of metal tubing between the piston and the groove for the e-clip, then re-install the e-clip. That is it.
