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Spridget race clutch questions

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Hi Billm - a jack Knight box has dog engagement like a Taylor but does not use Taylor/Hewland style gears. I guess they look like the standard straight-cut gearset. I suppose the way to identify it is via examination of the synchros - dogs rings and BMC-style synchros with the htree lugs do not look alike, as far as I know. If it is a dog box I might be interested, of course, offers like this always appear when I've popped the money for an alternative! I have my new SC gears and all the new parts needed for a new SC box, have the mainshaft assembled and will put the rest together this coming weekend.

Would this gearbox you have also have a front seal installed on the cover? just curious. Good thing my wife doesn't read these threads and get any ideas...

Perhpas you coulkd post a pic of the dogs/synchros so that an expert could opine as to what you have?

Ran a stock late-model box the last MARRS race, won on Saturday, had a big lead but frittered it away on Sunday and ended up 2nd. Interestingly, I drove the whole weekend using only 3rd and 4th, trying to save this street box. Got down to 1:29:46 driving that way, which was faster by over a second on previous best lap time. Go figure - think less, go faster. Thus endeth the rookie season after 35 years away from the sport.
 
By the way - how many needle rollers do the 2nd and 3rd gears take? My Bentley manual says the trans contains 58, which means 29 each. NFW I could fit more than 26 to either gear. I didd not count them taking the trans apart - and i simultaneously torn down both my broken SC box and a street box, in the process no doubt droping one or more needle brgs on the bench, so unable to work backwards to the right number. They are in tight, and I could not possibly have jammed in any more (smeared thin film of grease to mainshaft, placed needle rollers in position, then fitted each gear).
 
Here are some pictures of the trans-
It has NO input shaft seal.
I am asking $1000 (about 1/2 of MiniMania's price) and tax & shipping is included
Bill
 

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From what I can see (namely, 2nd gear) that appears to be a baulk ring box, not dogs. $1000 is a fair price - again, wish I'd known about this prior to obtaining a new gearset from England. Will mull it over as a possibility, though at this point I think I'm best advised to use the same money on horsepower. Regardless, you should be able to sell it fairly easily. Post it on the Prodracing.com site and see if you get any nibbles -
 
Bill, that SC/CR box looks pretty good inside, thats a very fair price for a assembled ready to go gearbox. You should have no trouble getting rid of it.
 
Bill, good deal, Oh and for anyone wanting a SC/CR box that may have missed out on this one, I have a good racing friend who has a good used one, he built himself, he builds race gear boxes. He is in the process of making his new line of Spridget dog racing gear boxes, so it's time to sell this one form his private stock. We in the future we also be making a dog race box based on the MGB 4 syncro gear case. These gearboxes and the Spridget dog boxes will be made of the best metals, best hardening prcesses and even REMed, chromemoly shift forks, first class stuff throughout. The Spridget dog race boxes should be ready by spring/summer 2011, the MGB box, a little later. I'll post details/updates here as they come available. All these gearboxes will have on track useable first gear ratio.
 
You have a mechanical issue. It is likely not a clutch issue..Might want to check for input shaft deflections or harmonic concerns , flywheel distortion or wobble at speed. Might even take a close look at the bellhousing or engine plate or input shaft bearing, pilot bushing? I have seen lightweight alloy flywheels do stupid stuff....no matter how much money you spent on the stuff. I race a car that is mild and pulls a real 105 to the rear wheels and I use a steel flywheel and borg and beck clutch. I have a new tilton unit hanging on the wall it has been there for a few years. I told myself that I would use it if the stock unit failed. I have never come off the track and said "danged if I only had a better clutch.
 
whatever, JR. All I know is that since I put in the tilton-style clutch my problems have been solved. Should have spent the money at the outset. This off-season's improvements include twin-master brake system (home fabrication, not too shabby thanks to my fabricator friend), rear disk brake conversion, re-calibrate corner weights, plus some minor things like improved cool air to carbs, ceramic coating of exhaust header & collector, and so on. Can't wait for the season to begin.
 
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