RE: [Chevelle-List] Restoring Problem, Transmission Bad.

[Mark Weber]

I am in Lakeville MN.   The trans is a Raptor 700r4 ( http://www.transmissioncenter.net/ ).  Mine came out of Louisiana though.  The reason I bought it was because of all the high end stuff they put in it.  My brother is an ASE mechanic and has rebuilt about 100 transmissions in his life.  He just builds daily drivers though with shift kits in them and did not want to build a high HP one and then have to stand behind it when the BBC had at it.  He read the spec sheet and agreed with everything they changed or modded on the Raptor.  He said they would be more expert than him on this type of build.   The TV cable was set correctly.  We spent about an hour getting it installed and set (and welding the flimsy Holly brand cable bracket etc.  Nice job Holley - there was 1/8 to 1/4" of play introduced with medium pressure on the bracket).    We did not put a pressure gauge on it however.  I heard that lower pressure will cause soft shifts too.  A trans may last many years under normal conditions with lower pressure, but when they get beat on it can cause problems a lot faster.  Rebuilt pumps supposedly have a higher rate of low pressure.  They rebuild the pumps there to keep the price down.   I did not like the torque converter from day one. The car had a vibration when the engine ran.  I am suspicious that the torque converter may have not been balanced 100%.  The engine is a 454 with an externally balanced flexplate (bought from transmission center) and an externally balanced fluidamper harmonic balancer.  The cam is a non-overlap comp cams model. The engine was built to run smooth at low rpm, idle nice at stop signs, and have plenty of vacuum for accessories.  Everything other car I have spins smoother at idle.    I am not bad mouthing this shop. The people there seem pretty decent when I talk to them.  I understand this is an area that is kind of gray.  The failure rate on transmission rebuilds in the industry is 3% I found out.  The failure rate of the Raptor is, well, a little higher than the industry average.   If I have them rebuild it they will put the warrantee on it again.  I will probably have it rebuilt, and if it gives me problems again I will switch back to the TH400 and live w/o overdrive.   Lesson learned:  Get it in writing.  Perhaps better to source things locally that are heavy, expensive, or complex.   Mark 71SS -----Original Message-----  From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Capt Crunch Sent: Wednesday, July 24, 2002 2:00 PM To: [EMAIL PROTECTED] Subject: Re: [Chevelle-List] Restoring Problem, Transmission Bad. Hey mark... where are you located at and where did you get the tranny from? What exactly was done on it? I know a couple guys that do Hi-Perf 700r4's. One will actually crack the tranny open while you watch and explain exactly what went wrong and what he will do to repair the problem. I had one done up for my last street rod firebird and was the best tranny I have ever had. Price was very reasonable too. There also are a couple companies out there with extremely good reviews. One is a place that recently hit it big, but I knew of them from my cuz. They are located in LA and have what is called a "Raptor" 700R4. I also highly recommend Art Carr. His 700's are masterpieces and are run by racers, off-roaders, and street rodders all over.   In terms of what I know about 700's... you don't need a shift kit for them really. Most mods can be made by a  smart tranny tech by drilling, replacing springs, and passage mods. The 700r4 is still the most commonly screwed up tranny. They need top be updated with numerous parts and they commonly had a 1-2 shift problem even in the late models. Many shops try to fix this by modding 2nd to shift in faster, but forget to modify 1st to release quicker, thus it binds and burns up #2 which was not a problem at the factory. This can also cause overheating and TC problems. Many people use a corvette servo which has mixed feelings by different shops. The skinny, the vette servo makes the shift rough because it is designed for a vette tranny w/ a special aux. Valve body. It does have more surface area which is why many use it. I have also heard of people using caprice servo's or custom built ones. "Alto" clutch packs also have mixed reviews.   Mikey