Bargain at $210K. Too much money for that car. I know what I would prefer, 10x 348s for the same money.
Fair bit of banter here, especially by non TR owners so here's the real goss from someone with three or four of the mongrel things. The 512M diff is a very robust unit and none have been known to break, even under racing conditions. They ARE backwards compatible and ANY Testarossa or 512TR / 512M from 1984 to 1986 share the same diff. Even a 365bb / 512bb can take this diff. The 512TR and M do use a different crown wheel and pinion but this isn't a concern unless you break the CW&P when your diff explodes. And I say WHEN not IF as it will happen at some point because it's a design flaw and a known POS! Yes, there are options, but these days if you purchase a factory part you will get an M diff. Newman in Canada makes a beautiful diff housing but you need to fill the guts of it with your own shafts / spiders / clutches etc and this can be difficult because when a diff lets go in a serious way, there is a better than average chance that the internals will be damaged also, as mine were. Modena engineering make a complete diff but supplies are seriously limited as they only do runs of ten units and who has a spare $80k to keep them in stock. Forza components in the UK also do a full replacement diff and I'm the Southern Hemisphere agent for this product. The other HUGE issue with the 365 / 512 / Testa / 512 series is the quill shaft that transmits the drive from the reduction gearbox through the diff housing and into the gearbox mainshaft. These have phenomenal twist loads on them and at some point the steel will lose it's 'memory' to return to the static position (no twist). The next time the car is driven, the quill shaft will snap like a ripe carrot and bits of hardened spring steel will distribute through your diff housing, potentially smashing the teeth off your CW&P. Not nice. CW&P from factory is $10-12k and there is only one or two known aftermarket manufacturers who still demand circa $7k USD for a replacement. With the upgrade of the heavy diff for the 512M (released in the last 6 months of 512TR production) the factory also released a larger quill shaft, up from 17mm to 19mm OD. Unfortunately they didn't do their homework and the new shaft didn't break, but it didn't twist as much as it was required to either. The consequence is that the new M quill shaft has a bad habit of tearing the end off the gearbox input shaft. $19k USD replacement, thanks very much Ferrari! I have new quill shafts manufactured and have sold them to all corners of the globe. They have been fitted to anything between a QLD 365 and a Koenig Twin Turbo Testarossa and 512BB LM race car. So here is the real low down. Buy a Testarossa / 512 and send me $5k USD and I will supply you with a new quill shaft and a complete new diff all ready to bolt into your car at it's next engine out service. I even have a selection of shims available to help set the diff up correctly and any good Ferrari specialist should be able to set up the diff in a day of mucking around if the engine is already out. Yes, if you run the gauntlet and you blow your diff you could be facing a $55k repair bill, especially if you damage your CW&P, or alternatively, don't drive it, don't push your luck, just have it serviced spend $10k on parts and labour to fit a new quill shaft and diff center and drive off into the future confident that under normal use, your Testarossa will not let you down. Until the fuse board catches fire and the ***** burns to the ground of course! But........................there is a simple fuse board fix for the 6 overloaded circuits that costs bugger all which I designed a few years ago. Fuse Panel Connector Failures Fuse Panel Repairs Page One
You have me a little confused Rob, if the diff explodes you could be up for a $55k bill but you have a diff for $5k ready to bolt on so couldn't a mad testarossa owner just drive it until the diff goes boom and then get a $5k diff off you ? Being backward compatible makes it a nice fix for the other model owners as well. You're a man of many tallents
C'mon John, read the damn post. Which part of when it goes boom it takes all sorts of thing with it didn't you get? CW&P for starters. $10 - 12k. Side diff carrier $2700. Quill shaft etc. Plus the gearbox strip down labour to make sure that all the little metal filings that floated into the gearbox are removed as they share the same oil. AND...................they have been know to explode so bad that they crack the gearbox casing. Do you really want to risk that? Seriously!!
I wish there was a feature where you could thank users that post useful information. Pity Rob Lay lives in 1978
Certainly does! Trent has a car in the event on a regular basis. Trent and Valentino discussing the steering in Trents Miura Image Unavailable, Please Login
Cheers mate, hope all has been well. Lol, born in 1978...........stuck in 1978. Yes, but let's keep that between us.
I always read everything you post Rob, it was just an observation. I have seen the prices of the gears when a property developer here blew up his testarossa gearbox and did "minimal" damage ($8k for a few cogs !!) I wouldn't go near a Testarossa, I'm not taLLented enough to muck around with one of them
Just because its in an Italian case its just a gearbox. you can have them made for a lot less than that. As good as Ferraris are there quality control has been some what lacking in the past.
