wattsworth

I did a recon at two local pull your part yards and found a number of Toyota live axles with 4 link suspension, panhard bars, drum brakes, and ratios from 3.4 to 3.9 from as early as 1978. Also present were two Toyota IRS limited slips: a 7.5" two-pinion from an '85 Celica Supra with the unfortunate trailing arm design and an 8" four-pinion with ventilated disk brakes from an '87 Supra with wishbone rear suspension. Seems like finding a good rear axle system for my project won't be so hard after all -- even if the elusive '85 AE86 live rear axle with disk brakes and a limited slip can't be found immediately. Any opinion on the merit of four pinion diffs vs only two pinions? One available choice is a 6.38" ring gear with a 3.909 ratio and four pinions. Would this be stronger or weaker than a 4.3 ratio 6.7" ring diff with just two pinions? I presume the 6.38" diff would be slightly lighter, which could be good.

Anybody in California have a 1985-ish AE86 Toyota Corolla GT-S parts car with a T282 or T283 rear axle they want to part with? Look on the placard in the engine compartment on in the driver's door jam for the code that looks like this: C/TR/A/TM 138 HR11 T282 T50 or C/TR GJ7/KQ41 A/TM T283/T50. These numbers are the Color (paint) code, Trim Code, Axle Code, and Transmission Code. Any help is appreciated!

You've convinced me to do a live axle. Thanks very much for making the pros & cons clear! I've found a stock axle that is perfect! It's a Toyota, lighter than an 8" diff, matches my doner well, has a triangulated 4-link suspension deisgn with rear disk brakes and an available LSD. Anybody in California have a 1985-ish AE86 Toyota Corolla GT-S parts car with a T282 or T283 rear axle they want to part with? Look on the placard in the engine compartment on in the driver's door jam for the code that looks like this: C/TR/A/TM 138 HR11 T282 T50 or C/TR GJ7/KQ41 A/TM T283/T50. These numbers are the Color (paint) code, Trim Code, Axle Code, and Transmission Code. Any help is appreciated!

Did some searching and found some enlightening answers: http://www.semasan.com/main/main.aspx?id=61557 Turns out the engine is the most important item and their are two ways to approach it: 1 -- Go through the SB100 process claiming that your Lotus 7 look-alike resembles a 50 year old car and pray you're get one of the 500 such VIN numbers they give out each year (Gone by Jan 3nd, incidentially). 2 -- Avoid the SB100 process completely and title the vehicle in the current year and depend on the Bureau of Automotive Repair inspector to decide the year for smog inspection purposes. If a range of model years applies to any particular engine configuration, vehicle owners will have the option to select the model year of emissions controls to be used. My doner has an engine of a range of model years that started in 1970 and ran through 1984. There's a good chance the inspector would decide it would be pre-1975 if I configure the engine as it was in that time period. I might not ever need to get it inspected again.

Anybody been through the California registration process for kit/built cars? How much can you change/alter/build a car before it isn't legally the same vehicle? As long as you retain the firewall and dash VIN placards, is it the same vehicle? I suspect you can do whatever you want to the suspension, gearing, driveline, and tires, but CA only really cares about engine alterations and emissions controls. So, perhaps starting with a 1975 or earlier doner, things get much easier? Or am I completely wrong? If you have to go through the whole process anyway, what is it? What are the pitfalls to avoid? Any help is greatly appreciated!

Guys, thanks for the ideas and feedback! Perhaps I should say what I'm after. My aim is to build a fun Locost 7. I'm not planning on putting in any major horsepower. I like simple, efficient, reliable equipment that I don't have to fix very often. Becoming a slave to a toy ($$ and time) just sucks all the fun out of it for me. Hence an easy to work on, rather bomb-proof old Toyota doner to start with (1600cc 2TC or upgrade to a bigger 3TC engine) . I might never visit a track -- just enjoy some twisty roads in good company. I'm willing to go to some extra trouble if it looks to be worth the effort, but I don't want to loose sight of my intended purpose ... fun! While the MBZ IRS is a trailing arm type of design, the hinge axis is not parallel to the half-shafts driving each wheel. As the suspension compresses, the top of the tire angles inward. When unloaded, the opposite also happens -- changing the camber. Have you guys looked at this? Is it worth anything? One thing I like is that the entire IRS from the MBZ is bolted to the chassis via elasnomeric mounts. Just loosen a few bolts and out drops the entire IRS with disk brakes at the wheel and parking brake cable. If the track-width is right and the weight isn't too bad, you can just bolt it to your frame and have the driveshaft altered to fit. It doesn't get much easier ... but is the complication of the MBZ IRS worth it? On bumpy roads the MBZ has some wheel-hop which I really don't appreciate. There were some MBZs with limited slips, but I suspect finding one in junkyards in my area is probably a lost cause. I agree that a live axle would be simple & reliable -- which is very attractive. But having basically no experience driving performance cars (my MBZ has a nice cushy ride, but it has no pickup at all), I don't really know what I'd be giving up by choosing a live axle over IRS. I do know that I can find all sorts of diffs for a Toyota 8" if I want to spend the money. Yes, I could probably arrange a rear disk brake conversion for a Toyota 8" axle to make stopping much more dramatic. I would also do a triangulated 4-bar linkage, probably with coil-overs. I do actually like a fairly hard ride so I can feel the road. So which set-up am I going to like better in the long run given my stated purpose? I really appreciate your help steering me right because I don't want to waste time or money and end up with something I don't like.

Locost builder newby here trying to weigh the merits of a trailing-arm independent rear suspension with few differential choices vs. a live axle with many choices for differential and gearing? For this Toyota-based Locost build, the rear axle choices are a Mercedes 240D or 300D IRS with disk brakes (LSD might be found, but they are kinda rare and very few gear choices are available) or a drum-brake 8" Toyota live axle with lots of different differentials. While I have both in hand now, are there better choices out there with a 5 on 4.5 wheel bolt pattern?