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re-posted from gtr uk site, tim @ svs who are quaife agents in uk, some background

Originally Posted by tim at svs xviewpost.gif.pagespeed.ic.71XfELIRfj.jp
Hope you dont mind me jumping on this thread. A little bit of history for you.
The original Quaife H-gate 6 speed was developed back in 1991 for Trust (aka GReddy) Japan. In those days the primary objective was to get an extra gear, with two overdrives (5th and 6th) so the top speed trialers could make 300kmh. It was never really designed for lots of extra strength. When you fit a new cluster of gears into any stock gear casing, you cant alter the diameter of the gears because the shaft positions cant change. So all you can do is improve the tooth design and possibly the width of the gears. All that was done as that product evolved during the '90s. Thing is though, by then most serious cars were making 750hp or more so the gears would eventually fail - due to their stock diameter. It was obvious something more serious was needed. The sequential is a completely different thing altogether and is completely different internally to the older H gate kit. Its a direct derivative of Quaifes universal 6-speed sequential, an entirely different product altogether. It was re-designed in fact to fit a new car specific 32/33 GTR casing, I know cos I lent them my car to model it on. The sequential has enormous gears by comparison to the H. I think there are about 65 sequential boxes around the world now and remarkably few spares have been supplied during the 11 years they have been out there. Spares are generally available at the moment, whereas for the older H-pattern, none have been made since 2001, so spares if not on the shelf have to be made to order, meaning much longer lead times. I think the most important thing to remember about the sequential, is its a racing transmission. It uses straight cut gears and is as noisy as you like. Not the preferred option for a daily driver really, but lets face it, there arent too many options available for the GTR. What I really wanted to do here was just answer the heresay and explain the product. The same basic principle goes for anything on the market - if the gear diameter is the same as standard, the strength is ultimately limited by that factor alone, so watch yourself spending fortunes on anything that fits into the standard casing.
The Getrag really intrigues me, so little info out there,but if you want to fit one of those in a 32/33, will need a 34 transfer and 34 gear ratios in the front and back axles, because all the ratios are completely different. As the 34 had a dual mass flywheel (as do Supras,M5's and 911 turbos), when you switch to a twin or triple with a solid flywheel, it seems to put alot of pressure on the constant meshing gears, or input driven pair as they are known. Whether these ultimately fail or just get noisier and noisier I really dont know. Getrags seem to manage 700hp quite successfully in the 34, Supra and others, so I assume it has bigger gears than the 32/33- Anyone care to comment on that ? The Quaife sequential is noisy in all gears however, as all of them are straight cut. As far as using it goes, you will either love it or hate it. It needs you to shift definitely and aggressively, mainly due to a mixture of the large gear diameter and the sequential mechanism being mounted on the side of the box. Treat it like a motorcycle gearbox, pushing it hard into gear, and you will get on with it just fine. Press it delicately and it probably wont engage the next gear up or down. What did Richard Bell say out of interest ? He hated his initially whereas Brian loved it. I sat next to Rich at that drift place in Wales and made him have a go with it properly, by about the 3rd lap he loved it. So much so that after two more sessions, he broke his lovely new engine !
Anyway, hope it was ok to post, just thought a bit of background might help
cheers, Tim

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