Trinten's SBC/F23 build - The work has begun! (Page 60/76) Will MAR 23, 09:47 AM I @$$ume you're talking about this GForce: https://www.gforcetransmissions.com/ I don't see axles and driveline components on their website, though. Trinten MAR 23, 09:52 AM As far as custom axles go? GForce is one of the people I've been talking to. While they don't list separate components on their site, I know they will sell at least a few parts individually (I asked and got pricing). They will sell their billet output and drive flanges. I'm also talking with another shop that does custom axle shafts, and sends the shaft along with some additional parts (boots, grease) for the end user to assemble. They do ask that the flanges be sent to them so they can ensure proper fit and what not. They are currently the way I'm looking to go. Other places I've reached out to haven't gotten back to me, or don't have the center shaft material in stock. La fiera MAR 24, 10:31 PM Me like a lot!!! Trinten MAR 26, 09:15 PM Today we got out the plasma cutter and took off the dogbone mount to get it out of the way, and did a little trimming on the 'box' for the decklid hinge on the passenger side. It'll eventually come off completely for FieroGuru's cool hinges to go back on, but for now just needed to notch it a little to give clearance for the coil pack bracket. With the engine back in, Mike took apart the inner side of the cv axle, and we put the output flanges in so we could take some measurements for the custom axles. Mike wasn't happy with the amount of wiggle on the output flange on the passenger side, so when everything comes back out again, he wants to dig into the transmission and make sure everything is okay over there. This is the still-unused transmission I got from Triple Edge Performance, so I really hope this is just fluke of some kind. He jiggled the one on the driver side and then the passenger side so I could see the difference, and I took some video of it. We also mocked up things for the A/C hose and marked them, so I can get the Fiero body-side hose ends put on the LS4 hose. With the measurements in hand, and worried about time constraints, Mike suggested something I hadn't thought to investigate, he suggested I call around to race shops that have machine shops (like the place that did my engine) and ask them if they can cut down my existing Corvette axles and respline the ends. We won't be able to beat on them, but it should let us drive the car and get it dyno tuned. Then the car can move under it's own power while we wait for the heavy duty axles to show up. Will MAR 28, 09:17 AM Where did you you get your 4T80 output flanges? Trinten MAR 28, 10:13 AM Hey Will, That's the best part. The output flange for the C5 Corvette is the same as that found on late model cars that came with the 4T80E. For example if you look on some Cadillacs that came out in 2000 (such as the DTS), it's output flange (what they call the inboard) is 41 splines female. Same as the C5 Vett. For comparison: GM8248 - Caddy part number ( O'Reilly auto ) GM8214 - Corvette part number ( O'Reilly auto ) When we mocked everything up, we had in the flanges from the Vette on one side, and the Cadillac on the other. Will MAR 29, 11:27 AM That's pretty awesome! I wonder if the same applies to the current 6T70/75/80 transmissions... Trinten MAR 29, 01:16 PM quote Originally posted by Will: That's pretty awesome! I wonder if the same applies to the current 6T70/75/80 transmissions... At first glance it doesn't seem to be that way. I pulled up a CV axle for a 2010 Buick Enclave (which should have the 6T75). The output flange (inner) is 27 splines. It appears there were two different generations of 4T80, earlier ones had a different spline count, so it could be the same with 6T75s, a more thorough check across their estate would be needed. Will MAR 29, 05:03 PM The F35 and F40 manual transmissions also have 27 spline side gears in the diff. Interdasting. Did GM finally standardize? Trinten MAR 29, 10:35 PM I would be amazed if they did. I would guess instead that the mathematical factors that the mech. engineers cranked out all were met by the axles (or at least output flange?) of cars that used the 6T70 transmission, so they reused in places? Like I had found an article on a Bonneville forum were a guy discovered that the same tripod and drive flanges (he called them 'tulips') were found on another car, which made it better for them versus hunting down the "Rare" SSEI axles. So I think GM just has some master database on parts like this, and they can drop in various forces or factors, and the spreadsheet goes "oh yeah, you guys made a few things that meets all these requirements..." I just wish us plebes could get access to that!! --- assuming such a thing exists.