Nixxa

I have looked into the archives and have seen many discussions on the X member and several pictures, any current member use this type of reinforcement(reference to the X instead of the H or hybrid? have any pictures? any other ideas for frame strengthening and rigidity?

Also where can I find a beefed up rear diff that will fit this car with little to no mods. Dana? Currie? Any other ideas?

thanks in advance for the help! :thumbs:


[Modified by Nixxa, 10:38 PM 4/21/2004]

GrandSportC3

Don't know any upgrades to the crossmember.. However - the only real upgrade to your posi case is to go with the 12-bolt internals.. However - that's only needed if you have over 500 HP and run slicks. If you don't run slicks - the standard differential internals will be strong enough..

Nixxa

what about a torque rating on that too?

LT1driver

contact Toms, not sure of web address but someone will chime in, check archives and it has been listed

GrandSportC3

I would estimate that a stock differential can take 400 - 450 ft/lbs of torque on slicks... It might witstand more.. but not for too long...

GTR1999

You can do some mods to the differential to help beef it up without going the 12 bolt route. Polish the carrier and deburr it. radius the edges,Use 10-17 posi gears and "tune the clutches"and use the solid steel ones. Switch to socket head cap screws on the bearing caps or step up to steel bearing caps with 1/2" bolts. You can get treated gears and side yokes too. If thats not what you want then you can start with more intense mods,like HD splined yokes,or the 12 bolt. How much Hp/Tq are you going to apply and what are you plannig on for the car?
Gary


[Modified by gtr1999, 9:06 AM 4/22/2004]

Nixxa

I have no definites yet for components of the motor but am looking in the range of 450-500 hp and around 500-525 ftlbs of tq. Although I know there are those out there ready to just jump at it being more of a street car, and eventually I would think I'll be able to get it to show quality, not necessarily to stock specs, haven't really considered drag strip at this point as I'm not even close to throwing it on the street anytime soon. But thats definitely what I'm looking into for power rating of the motor. but i just want to make sure i have all the bases covered for any possible future probs that may affect the frame and rear gearing with that kind of motor.

Solid LT1

Unless you are going to seriously drag race your Vette, the blueprinted stock differential as described above is a good way to go. The Vette rear end "lived" behind 600HP L-88 stuff in endurance racing so a street motor should'nt be a problem. I have a polished posi case, 17/10 gears, chromemolly side bearing cap with 1/2" bolts (driver's side only) and 18 plate (solid posi plates NOT the "daisy" plates, they are JUNK and I don't think much of the new carbon fiber stuff) posi unit. My rear end was done in 2000 by myself with input from my fiend Dave Herlinger at Corvette Repair in Mtn View, CA (do an internet search.) The differential has survived many strip passes with slicks (I don't "side step" the clutch but agressivly engage it at about 3000 RPM.) I sure do scare my friend Dave with my starting line technique but the diff is still doing well at the drags and autocross races although I have a little howl on the coast side when deaccelerating. Tom's differentails has many good parts ncluding the solid posi plates BUT, I would use International Axel parts for side yokes and spindles before I bought Tom's K/A stuff! My 2 cents, Eric

NHvette

Another cheaper option would be to weld in the mounting brackets for the older
style steel crossmember and iron case. I'm no expert here, but I thought I
read that the aluminum case was the weak link.

:seeya

Solid LT1

I think the iron case and aluminum one have the same mounting surface as I recall. I did not know the guy was fighting one of these POS! and yes they are a POS! compared to the ease that an early differential can be set-up. The aluminum case pinion shims are positioned between the bearing races and the case and the differential side bearings hold the side pre-load spacers between the posi case and the bearing, these things are a total POS! to work on!

71coupe

I think gkull had a new Tom's axle go bad. You may want to look him up.

kanka

Hi Nixxa , Maybe I can help you a little. I have a 1978 with a 406 cu.in. in it with about 475 hp. I run a th350 auto trans. from B&M ,Ialso have a hole-shot converter with 2400 rpm stall. I had Dan Vansteel build my rearend, it has 4-11 gears. Trust me your fram and diff. will not be your weak spot. The big problem areas will be u-joints and your rear spring. I switched to brute force u-joints (on grease fittings) .Dan said to use a 420# carbon fiber spring to keep the half shafts from going horizontal on launch. I also used poly bushings on my trailing arms and strut-rods. NO problems.