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GI 2.93 1" gearsets, "Mr Norris' third fist" brace



Although I'm not a transmission expert, I doubt bracing will make the 7/8" chain much stronger. It can't hurt, and will help a little.

The reason I say this is in my business, we work on turbo snowmobiles making as much as 600HP. We have a chaincase setup that is very similar to the 4t65 transmission.
The stock chains are "silent chains" and are weak. They stretch, start snapping links and then break at 300HP with good traction. The solution is a set of 15 wide Hyvo gears and 7/8 Hyvo style chain.
Which is easily twice as strong. We are able to handle 600HP with that set up for racing application. The factory bearing setup in the chaincase is a "swivel" bearing able to compensate for chassis flex and driveshaft flex. The chaincase is a super weak and brittle magnesium. Very very thin material, around 1/8" thick ... yet it can hold a lot of power.

There are aftermarket mounts that completely eliminate the flex in the chassis allowing for standard bearings to be used. This is no way helped the stock chain hold more power. Hyvo gear setup is still required as it is the chain that is the weakness. A slight amount of flex will not hurt the chain.

So the chain and gear style/size strength is really the weak point in our setups and I think short of a 1" GMR chain, not much will hold the power the turbo cars can produce on the long run.
 
it's really difficult to get pictures of but I have almost 5thou deeper grooves on the stator support side of a GMR Gear from a 870 wheel horsepower car that would seem to indicate that the twisting and misalignment means that only half the chain is actually carrying the load. Without that misalignment more of the 7/8 chain will carry the load.
are 1 inch chain has not had near as rough of a life but even then you can see the inside shows more wear than the outside.
funny thing is is you know damn well GM knew it was a major issue so they fixed it with the 80e with the additional bearings, as well as the large ball bearing for the sprocket.
considering how large and flat half of the casting is around the 65e stator support I would guess that it's deflecting even at lower horsepower levels.
 
I'd be in for one.

I already told Dave I was down for it when I was up there eating all of his food and drinking all his beers.
 


Turbocharged400sbc said:
it's really difficult to get pictures of but I have almost 5thou deeper grooves on the stator support side of a GMR Gear from a 870 wheel horsepower car that would seem to indicate that the twisting and misalignment means that only half the chain is actually carrying the load. Without that misalignment more of the 7/8 chain will carry the load.
are 1 inch chain has not had near as rough of a life but even then you can see the inside shows more wear than the outside.
funny thing is is you know damn well GM knew it was a major issue so they fixed it with the 80e with the additional bearings, as well as the large ball bearing for the sprocket.
considering how large and flat half of the casting is around the 65e stator support I would guess that it's deflecting even at lower horsepower levels.
Click to expand...

I guess it's possible if the alignment is that bad, that could cause the chain to break prematurely.

Just as a reference to my post here are the 7/8" hyvo chain/gears we use in the race sleds.

Here's what happens to stock chain right before snapping...

images


Stock setup and magnesium chaincase

2012ArcticCat122.jpg



gears__34133.1405429839.1280.1280.jpg
 
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Funny you should mention yet another way the 80e is better yet most people still insist on band aid over band aid over band aid to make a 65e work..........

I wish James and Dave would focus on making the 80e a viable option that in the long run cost half as much with half as many band aid issues to worry about!

Minus the fabrication part of an 80e install and the soft third, how is this not superior in every way? The time and money invested to bandaid a 65e baffles me.
 


yeah, we wish we had a sweet ass sprocket setup supported by two bearings across a 1.5 foot gap. only deflection you get is probably from the shaft flexing in the middle and slight bearing wear.

by contrast the 65e input drive is in a fluid support on one side with no mechanical limiting of radial play inside the converter (turbine) while at the other end its supported by a small needle bearing at the sprocket centerline with a sleeve/teflon seal design thats supposed to let it move around and account for tollerance stacking of the trans case parts....

now see that the needle bearing and the turbine are no more than 5" apart....so not only does it have massive play built into the design, the bearing, the only solid runout controlling part of the whole mess...is located in the middle of a 12" dia 3/16ths to 1/4" thick cast aluminum plate...with no real room for stiffening ribs due to packaging constraints.

the driven sprocket is nearly just as miserably mounted

your chain drive means the strength gain from widening should be fairly linear as the inboard and outboard links can carry nearly the same loads.

on ours 1/2 of the chain width is carrying the brunt of the loads while under the most stress. we gain only half the strength of a wider chain.

mount your far side bearings in rubber and see what i mean.

i know one drawback to that style case is that the shafts can "whip" as they flex which ****s **** up especially if the resonance frequencies end up reinforcing at some point (there's a whole lotta math i dont frankly follow) but its analogues to the rogue wave, where momentary overlap of varying waves great a single massive spike/anomaly.

ive seen the billet cases that include a third bearing to support those gears by both sides... only deflection possible is bearing play and the case flexing itself

id give anything to have that. but alas the 65e is a compromise to increase the strength of the 440t4/4t60/4t60e, where the 80e seems to have been designed from the get go to drive a small military tank...or a cadillac...remember back in the day when the american dream was a cadillac in every driveway?

cadillac coulda put some sweet sc 3800's in those tanks and made a killing...but nooo someone decided that the awesome "success" stories of the quad 4 and LQ1 should be in a similarly awesome "modern" v8 when they ditched the 4.5/4.9L

im almost positive thats why GM went so bonkers on the ecotec 4 banger drag program to make sure those ****ing motors were good lol

show me a awesome N*/3.4 TDC/dohc quad 4 owner and im sure they can tell you the number of expletives and dollars invested is proportional

dude ive been fighting this damn TR's trans for years after what was a nearly headache free tenure of junkyard 80e's in a whipple riv. i ****ing hate the 65e
 
James, was it ever confirmed that LSmotors won't fit? While I was doing the oil pan last night on my motor it really had me wondering
 
the primary reduction planetary in the 80e occupies the same space with the lower ls4 block skirt. since the block/trans is alum and weldable its possible it can be made to work
 


the final reduction planetary is the diff plantetary. on the 80e all ratio changes are through this planet, this keeps the tq loading of all the other gearsets far lower than normal 65 which has different chainsets that change the tq the geartrain see's.

imagine this when you look at the pics you took of the underside of your cradle (you did take pics right?)
 
id say that looks like a whole lotta "yer fawked"...i tore one apat for the trans case core (gotta be skillfull to remove starter and not snap the damn bell)
there was like zero room, the engine to diff brace/bracket is like 1/2" wide and the 80e is at least two inches bigger OD at the diff surface.

id bet it'd be possible, but it'd take modifying the case and block
91parkave said:
tvmlaGM.jpg
Click to expand...
 
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