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I saw it on one of the Facebook Corvette groups. I should have taken a screenshot of it. It would be nice to be able to use the Eaton Truetrac posi and save some weight.
$4550 & out of stock - Hammerheads website is a joke. Pricing was off of GearFX. Detroit Speed seems offer them also, but also out of stock. I assume it's probably custom order.
I spoke with Fuzzy at GearFx last year, he is a nice guy who knows his stuff. He had asked me about some diff questions and wasn't too keen on doing vettes due to the long hours involved. Only guessing here but they probably build to order since there's not a huge market in expensive diff conversions and supplies have been back ordered due to covid. Many bearings were not available for months, not sure what that status is since I stocked up on bearings and haven't had to buy any in some time.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by ratflinger
$4550 & out of stock - Hammerheads website is a joke. Pricing was off of GearFX. Detroit Speed seems offer them also, but also out of stock. I assume it's probably custom order.
Man, that's a lot of money. Hopefully there's a significant strength improvement in that setup, as the differential housing is just about the least efficient place to spend money on weight reduction.
Man, that's a lot of money. Hopefully there's a significant strength improvement in that setup, as the differential housing is just about the least efficient place to spend money on weight reduction.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by Pale Roader
Aren't you using the aluminum C4 rear in yours?
Nope. C4 D44 units are damn expensive, and IIRC they don't package well in the stock C3 floorpan. I'm using the stock C3 differential (strong, cheap, and plentiful) but with a C4 D36 batwing (lighter than the C3/C4 D44 batwings, 20# lighter than the stock C3 cover/crossmember, and dirt cheap and plentiful). Did some cutting, narrowing, welding, and re-drilling to make the D36 batwing fit my differential. Here's an old picture, during the process, doing a test fit on an old C3 case.
Nope. C4 D44 units are damn expensive, and IIRC they don't package well in the stock C3 floorpan. I'm using the stock C3 differential (strong, cheap, and plentiful) but with a C4 D36 batwing (lighter than the C3/C4 D44 batwings, 20# lighter than the stock C3 cover/crossmember, and dirt cheap and plentiful). Did some cutting, narrowing, welding, and re-drilling to make the D36 batwing fit my differential. Here's an old picture, during the process, doing a test fit on an old C3 case.
Didn't want to chance the later aluminum C3 diff? Thats what i'll be aiming for... a complete 81' pullout, with the FG leaf, and maybe the C4 batwing like you have if i can figure it out. But i'll be running 350rwhp. Maybe as much as 400, but no more.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by Pale Roader
Didn't want to chance the later aluminum C3 diff? Thats what i'll be aiming for... a complete 81' pullout, with the FG leaf, and maybe the C4 batwing like you have if i can figure it out. But i'll be running 350rwhp. Maybe as much as 400, but no more.
Well, it didn't look like a good gamble when I was trying to fit the C4 suspension under my car. I know some guys are having some decent luck, durability-wise, with the C3 D44 unit, but I wasn't in the mood to gamble it behind a big block.
Would have been nice if the volume/economics of the original rear end had allowed continued production but with a change to aluminum in the housing material.
Tom Watt, of Tom’s differentials used to have an aluminum case on his website with coming soon written underneath it. They were thinking about it but never got it done I guess. I also wish someone would make a modified stock case which would allow a 12 bolt build with the taller 3 series gears. I like my 3.08’s with a 1 to 1 high gear. Hope I don’t kill my best of everything 10 bolt build. Oh well. Can only wish. Maybe these Hammerheads will be a good solution as power is just too easy to build these days.
Bill
Last edited by 69ttop502; Jan 25, 2021 at 05:09 PM.
Not quite what was being discussed here - more along the lines of a completely new alum HD diff
I took it as using 2008 Ford Explorer IRS 8.8 and adapting it to the Vette but that can’t possibly be economically cost effective. If someone just wants HP security a 65-79 iron housing and the kit is all that’s needed
Outfit called Hammerhead was and maybe still is producing a horribly expensive 12-bolt diff for a Dana 44 housing. Not sure of the gear set inside. Only cost effective if you are running 1000+ HP
Hopefully there's a significant strength improvement in that setup, as the differential housing is just about the least efficient place to spend money on weight reduction.
