Better Gears for a 450

[drm261]

Does anyone know where I can get performance rear gears. I think that the stock gears are 3:06. I`d like to find a ratio closer to 3:70. I`ll even consider changing the rear with another model that will bolt in. I stopped by Renntech in West Palm Beach but unless they are doing the work, they don`t say much.

[smallblock450sl]

Originally Posted by drm261

Does anyone know where I can get performance rear gears. I think that the stock gears are 3:06. I`d like to find a ratio closer to 3:70. I`ll even consider changing the rear with another model that will bolt in. I stopped by Renntech in West Palm Beach but unless they are doing the work, they don`t say much.

I've been searching the same issue. I've heard of 3:46 gears (like out of a 80's 350sl 4 speed car) Some very knowledable moderators have quoted "they are a bolt in replacement". I understand that the differentials have the gear ratio's "stamped" on the housings. (haven't had mine up in the air yet to check. I tried different gear manufactures on line-emailed-no awnsers back. Hope other posters will comment on this topic. I'll be watching this post for shure.

[Bondavi]

A 450?? Are we talking the same 4.5 liter with 3 speed auto here? Changing the rear end to a lower gear will REALLY kill fuel economy.....and the engine! It already does 3500rpms around 80mph, so imagine ~4k rpm's doing only 60.

If this is going to be a dragster, disregard my post.

Good tool here: http://www.corvetteactioncenter.com/tech/tools/rearend.html

[drm261]

First, if I gave a rats rear about gas mileage I`d buy a Hybrid. Second, this is my sporty little baby with little spunk. I know what your saying about RPM`s but I only drive my 450 around town. When I get on the highway I drive my Hot Rod thats faster than radar. I`m looking for stop lite to stop lite fun.

[smallblock450sl]

I can't speak for drm261, but we both have 450sl's with Chevy smallblocks and 700r 4 speed auto tranny's. I dont want a dragster, but I do have a more powerfull engine plant and a better 4 speed tranny than came with my wonderfull "SL". My problem is not RPM's it's MPH. I don't live in a state with unlimited speed limits (like the autobaun-these cars wear designed for). I do have a passion for cars, weather it be "Factory Correct" (I spent 15 plus years in Vette clubs and know where "purists" are coming from) or "Modifeid" to my liking. If you had a chance to drive either one of these cars..............You to might consider the change, reliable/inexpensive parts (relativley)/more power/more tourqe/more gears, ect. I'd just like more gearing in the rear end to make my 3800 lb car perform. That is why I have asked these questions on this forum, becuase "Who" would better know Mercedes cars better than Mercedes owners and Purists. Thanks for reading and I would look forward to any comments and any help on the rear end upgrade. Dave

[page62]

A better swap would be a manual transmission. You could find an early R107 350SL and use it as a donor.

Even if you swap out the rear gears, you're still dealing with that nasty old slushbox...

[t walgamuth]

the 369 ratio from the 240d may work.

tom w

[jdhill]

See if these help.