CamMan83

I am having an issue w/ my 700R4 in my IROC. It was rebuilt some time ago, probably 25,000 miles ago. It worked flawlessly for that whole time, then one day I was out testing some new motor mods (550 HP supercharged SBC) and the trans gave out after about the 3rd time. I was stopped and hammered it down the track it would shift 1-2-3, no problems. Then on the 3rd time it felt like second was gone! I figured it was the band but I wasn’t too sure so I started to inspect things. The transmission has the Vette servo and the .500 boost valve. I also have a B&M cooler installed. The 1-2 accumulator is shimmed to about 1/8th in spring out. It is installed like so: housing-shims-piston-spring. I dropped the pan and the fluid was fine, did not smell burned and there was no excessive material on the magnet. I changed the fluid, replaced the servo seals and checked the governor. The 2nd gear servo (apply piston itself) was extremely hard to remove so I figured maybe it was binding and not applying the band. Well after installing everything again 2nd felt much stronger but the 1-2 shift was still very sloppy and rough. There is a lag/slip and it vibrates noticeably. 2nd gear holds when it’s applied all the way up to 5500 RPM and holds under boost. The 2-3 shift is very firm, like usual. It almost feels like a slip, then double apply into 2nd. The TV cable is adjusted properly. When it is shifting at lower RPMs it is worse. When I gas it up and let if shift automatically at a higher RPM it shifts firmer and smoother. Any ideas? I’m starting to run out? Feel free to ask any questions I will be monitoring and replying as quickly as possible. All your help is much appreciated.

bluechev

id try pulling out the boost valve maybe its hanging up