Gearbox upgrade - MX5 to M series engine

Have you looked at the lexus IS200 box...

www.cars-data.com/en/lexus-is-200-executive-specs/20630/tech

Similar numbers and I think its what Keith is hoping to use :whistle:

re the viscous coupling - could this be a cush drive type idea to smooth it out somehow?

Busta - I dont think John is after quite the performance style of the MX5. Ive driven his before the chop and tis surprisingly nippy for a 1.3 and a lot faster than many standard Jimnys ive driven (faster than my 1.8 was then too), The further mods should help, along with the weight loss. I agree that the gearbox change purely because of ratios is a bit much, but some improvements are to be had from the 6 speed arrangement and the slightly smoother progression through those gears, making two good reasons to look at it

I hadn't considered the Lexus box at all Riccy..... It is a nice gear set but I've never driven one....

Keith sent the CAD files as mentioned and also sent some pictures of his freshly machined alloy weld on bell housing adapter. Super impressed, he"s quite the engineer.... I eagerly await his progress. He might have a customer before he finishes the job lol. In the meantime, I am going to go for a test drive in a manual Lexus if I can find one in a local dealer....

I will be speaking to the CAD designer either later this week or early next, whist there, I will ask as to why viscous couplings were mentioned, they may do something with them on their built cars. Intriguing.....

Busta - I feel that no matter my approach to the car, you would be negative, you seem to be that way...... If you could have "no interest", that may be best....

sniper

I have the answer. Quaife. 7 speed close ratio sequential. Rally car styleee! Brrrraaaaap!

I would fit a Quaife box at the drop of a hat Lambert, happy with a 4 speed but even that is around 2k..... Sadly the car does the brraaappp thing now lol, just not the go to match :laugh: :laugh: :laugh:

sniper

sniper wrote: Busta - I feel that no matter my approach to the car, you would be negative, you seem to be that way...... If you could have "no interest", that may be best....

sniper

I do have an interest, hence involving myself in the discussion and sharing my experience from similar investigations into the compatibility of MX5 parts with the Jimny. If I come across as miserable it's because I struggle with all the bold claims, waxing lyrical and hyperbole. Unfortunately I'm only actually interested in what works and what doesn't.
You seem to object to me pointing out some facts that I have learnt from my own research into the matter. I'm always happy to be corrected if the information I've given is wrong but you dismissing my points with your blind faith in some unnamed engineers doesn't help the rest of us understand if it's worthwhile, or to persuade anyone to part with their money.
The simple fact of the matter is the proposed gearbox swap will do nothing to achieve your primary goal of shortening the ratio of 2nd gear. I'm very sorry that that information had to come from me and not someone you'd consider an authority on these matters.
I'll leave you all to fantasise about gearboxes now. I've got an engine to fit.

Boom