I think I raised the option of buying say 20 boxes from him once; he didn’t seem that interested.
I agree that once available the boxes should sell well. I would certainly buy at least one.
I agree that I wouldn’t hold out for the JT5. I held out for about a year and then gave up. The Jag shop who did my transmission offered to buy 10 from him and it didn’t change anything. I also was told that if he ever does produce them again he will only sell to certain shops and not to individuals but who really knows.
I’m going with the driven man(American Power Train) tremac 5 speed. This is for my D build we are currently working with Centreforce/Tilton on a slick release bearing set up.
An important bit of advice for anyone ordering a five speed based on T5 gear sets. Decide on your tire size and pick your speedometer. Then have the builder install the correct speedometer drive gear on the tail shaft (there are many options: 6,7, 8, 9 or 10 teeth). This is a simple choice while the transmission is a-buildin’. Once the box is assembled and in the car, it becomes a big, expensive job to change. If you pick the right drive gear, it’s a snap to recalibrate the speedometer by swapping driven gears in the the transmission pickup. If you pick the wrong one, you will never have an accurate speedometer.
I’ve put up an Excel spreadsheet that will help with the calculation. The green box allows you to vary input data. When it opens, it’s set up for stock tires and a 3.54 rear. To perform the calculation for your own situation, you need the tire width and aspect ratio, differential ratio, and the TPM of the speedometer head. If you want to check the accuracy of your speedometer using an electric drill, you can input the RPM of the drill. You can change the tooth count of the drive gear as well. Finally, you can experiment with % tire wear to see the effect of that. What you want is a drive gear that allows you to pick a driven gear towards the middle of the range…say a blue or white gear. That will allow you to easily recalibrate if you later play with tire size.
http://www.coolcatcorp.com/Speedometer/Speedometer.xls
Illustration of drive and driven gears, along with output housing and retainer:
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Going way back to near the top of this topic, did I read correctly the advice to raise the gear-lever height adjust the bulkhead stabiliser? That sounds a recipe for torn bulkheads. The stabiliser is just that, a stabiliser, it shouldn’t form part of the engine gearbox support structure.
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It doesn’t become a support structure. But if you have to adjust the height of the transmission, the stabilizer height needs to be adjusted accordingly.
If you mean the reply from Uryk, that was not to raise the shifter height. That would be dangerous because you’d be asking the stabilizer to take the weight of the engine/gearbox, very bad. He was suggesting using the stabilizer to push down the assemble a bit in case there are interference issues with the shift tower. In this case the only force the stabilizer is working against is the spring force from the rear transmission mount. It’s quite negligible really.
Thank you for this. It answers a lot of questions I had.
I might just be over cautious but I’d still be reluctant to ask the stabilizer to perform a function it wasn’t designed to do.
If you think about it, it’s taking these same forces while driving. The sprung gearbox is bouncing up and down. If excess wear was going to show up, it would manifest first in the two rubber stabilizer bushings. I can’t imaging bulkhead metal getting distorted. That sort of thing happens when someone fails to fully tighten the stabilizer stepped washer and the engine gets lifted as the nut is tightened.
If you preload the transmission mount spring, compress it beyond what the normal weight of the transmission would do, wouldn’t that leave a smaller amount of compression travel which could lead to the spring being more easily fully compressed during normal operation. That will put an undue stress on the stabilizer mount.
I get the feeling from our exchange that the amount is rather trivial. For example he says that the 4.2 hump clears fine, and it isn’t much taller than the 3.8. 1/4" maybe? I certainly would think twice before stealing an inch of travel, but a very small amount seems fine to me.
When I first got my S1, the firewall metal where the stabilizer mount is welded was cracked. I assumed it was due to improper stabilizer adjustment.
Tom
My bulkhead was torn. So I guess the metal gave before it could get distorted