Hello,im new to the board here.with that said id like to give some of you an idea of how i see the world of automatic transmissions and an idea of my unique understanding of them.it is a gret thing to share technical information i have gathered on the gm family of automatic transmissions.if you are looking for real answer to real questions about the priciples of operation and theory of automatics as well as quick path to troubleshoooting anything related to them,just post and ill do my best to provide you with the facts.several questions are asked about recalibration kits etc ,so to start off id like to share some info that is commonly asked about them.i keep a huge database of my responses so they can be quickly accessed without having to start over.......we are successfully using the 700r4 at above 550 horsepower .there are several things that need to be addressed with the unit to make it live.because of the reversal of the held and driven members of the planetary geartain as compaired to the other common gm 3 speeds and overdrives ,the planetaries,input sprag and reaction tube are put under a severe strain when operating at speeds above 6000 rpms.using the 2003 and up 5 pinion planets and heat treating the reaction tube to a prescribed amount greatly reduces the rotating speed failures.when operating in overdrive the principles of operation dictate that output speed is faster than input.this generates abnormal rotating speeds at the sprag and input sun gear causing centrifugical loads on the sprag to remove lube oil and physically stress the dog bone holding elements of the sprag.correcting loss of lube at the output shaft and input housing doubles lube oil counteracting the reduced lube encountered during normal internal component rotation.our production of the 2.66 first gear 700r4 has proven to be the ultimate cure for rotational speed insecurity inside the transmission.this also produces a more favorable gear ratio for accelleration reducing the rpm drop between gears by bringing the ratios closer together.shift recovery rpm is also reduced .in a turbo,supercharged,n20 and some fuel injected applications this rpm drop is of no consequence because of the abundance and placement of torque in the engines operating range.with a carburetor however this rpm drop introduces severe vaccuum drop across the barrels of the carbuerator disrupting airflow into the engine and consequently reducing the engines ability to gain rpm against road load,inertia ,the weight of the vehicle and drivetrain absorbtion.the 3/4 clutch pack needs a specific thickness ,amount and type of friction and steel plate as well as controlled clutch pack accumulation in order to produce proper application.this has been studied and tested by us to produce the most effective means of carrying the compound planetary gearset at the same ratio as the turbine shaft to initiate third gear.this is no easy task due to the speed biasing and weight of the geartrain as well as loads on the output shaft due to the weight of the vehicle and other introduced loads as mentioned previously .hydraulic calibration is also an issue.some of the most well known builders of this transmission use trans go kits to improve shift quality.the kits removal of the main third accumulator orifice in the seperator plate introduces a unique set of problems specific to the 700r4.in the efficiency department the input clutch housing is as much as 2/3 s less power absorbtion in power loss when compared to the direct drum method of introducing direct drive.the clutch housing and frictions always turn with the engine to reduce operational power loss.we are also working on a way of using the reverse clutch in third gear,in the way some have done it with the ford aod.line pressure must also follow engine torque .we have developed an absolute for operating pressures for high horsepower.minimum line pressure at idle with 0 tv should be 90 psi.just what the tv limit valve feeds the plunger.maximum line pressure with full tv should be 235 psi.if the throttle opens from 0 degrees closed to 90 degrees wide open than we should understand that for every 25 percent,1/4 ,or 22.5 degrees of throttle opening the pressure should rise 36.25 psi.this should happen at a uniform rate which means the original line bias circuitry must be re engineered .this doesnt happen by blocking the valve wide open either.accumulator valve circuitry in another post.

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how much power are you guys putting thru these things?

 

With a well built one you can but 500-600hp hp through it no problem, PM 12CNDZ about it he is the 700R4-4L60E guru. and can build you a really tough tranny to take what you will give it.

 

Yesterday I was out driving my '86 IROC (it has a corvette 350) and I went out on the highway and stopped , warmed the tires up and then went throght the gears at the 1/4 mile we have marked off and when I crossed the finish line and let off and now the trans buzzes and there is no gears ,it bearly moves .
what do you think broke ?

 

do you have reverse?if you hear a buzzing sound with little or no movement it sounds as if you broke the pump rotor or converter hub.remove a cooler line from the radiator and start the engine.does 1 quart of oil exit the line every 30 seconds or just a few drops?no oil ,broken pump rotor or converter hub.if there is oil you may have broken the input drum ,input housing or the converter turbine.

 

I have no forward or reverse