Amy Wade Posted July 11, 2022 Share Posted July 11, 2022 (edited) Hi peeps, Does anyone know if a gearbox from a late 1500 will be a an easy fit into my Mk3? Will I need to use a 1500 flywheel & clutch etc? Edited July 11, 2022 by Amy Wade Correction Quote Link to comment Share on other sites More sharing options...
Clive Posted July 11, 2022 Share Posted July 11, 2022 for the clutch you can use a dolomite 1300 clutch plate. The other problem will be propshaft, it needs to be a few inches shorter (in fact a mk3 od propshaft is the same length as a 1500 non od prop) and the diff has a small flange, but a 1500 box has a large flange. Quote Link to comment Share on other sites More sharing options...
PeteStupps Posted July 11, 2022 Share Posted July 11, 2022 Clive could the 1500 gearbox output flange be drilled for 5/16" bolts? Or the prop flange for 3/8. I remember that being suggested when I had a mismatched OD. Quote Link to comment Share on other sites More sharing options...
RobPearce Posted July 11, 2022 Share Posted July 11, 2022 If a 1500 OD propshaft is the same UJ system (rather than a CV one, which I believe some were) then it's possible to swap one of the flanges to suit the diff. Otherwise, using the 1300 Dolomite clutch as Clive said, and the 1500 mounting plate, it should fit fairly easily. Bear in mind that the shift pattern is different and you'll need the 1500 gearstick. Quote Link to comment Share on other sites More sharing options...
glang Posted July 11, 2022 Share Posted July 11, 2022 Hope the gearbox cover will be ok as have read of problems because the gearlever pivot point of a single rail is quite a bit lower than the original.... Quote Link to comment Share on other sites More sharing options...
Clive Posted July 11, 2022 Share Posted July 11, 2022 1 hour ago, PeteStupps said: Clive could the 1500 gearbox output flange be drilled for 5/16" bolts? Or the prop flange for 3/8. I remember that being suggested when I had a mismatched OD. Not sure.... I have seen several diffs (round flange type, so NOT original early spit/herald type) that have the flanges redilled at 45degrees to mate to a smalll flange prop. Quote Link to comment Share on other sites More sharing options...
drofgum Posted July 12, 2022 Share Posted July 12, 2022 Amy, At the differential the small flange from the existing prop shaft could be moved to a 1500 prop shaft. The universal joints are the same. Cheers, Paul Quote Link to comment Share on other sites More sharing options...
Amy Wade Posted July 12, 2022 Author Share Posted July 12, 2022 Thanks for all the replies, at the moment I'm negotiating purchase of a complete 1500 car to strip for parts. It has an overdrive gearbox & was expecting to have to use the propshaft, I wasn't sure about things like the flywheel/clutch. It looks like I'll need to look at either swapping differentials or doing mods to suit. As for the car I plan to strip for bits, the tub is made of Swiss cheese, mice have used it as a home & the engine is rusted up solid. Anything salvageable that I don't need or have use for will be offered through the forum to hopefully keep some better examples on the road. Quote Link to comment Share on other sites More sharing options...
Clive Posted July 12, 2022 Share Posted July 12, 2022 You will indeed be able to use the prop, and you can use the 1500 diff (assuming a spitfire!) Using the rear spring, and matching front ARB is a good idea too, the car will feel better for it. Quote Link to comment Share on other sites More sharing options...
Amy Wade Posted July 12, 2022 Author Share Posted July 12, 2022 13 minutes ago, Clive said: You will indeed be able to use the prop, and you can use the 1500 diff (assuming a spitfire!) Using the rear spring, and matching front ARB is a good idea too, the car will feel better for it. I had done the swing spring conversion last year & it transformed it. 1 Quote Link to comment Share on other sites More sharing options...
RobPearce Posted July 12, 2022 Share Posted July 12, 2022 30 minutes ago, Clive said: you can use the 1500 diff I have 1500 Spitfire type (3.63:1 ratio) diffs on all three of my Triumphs and do feel they're a good option. However, mine are all 1500 or 2L engines - the longer gearing may not work so well if you're still on a Mk3 1300 with the hotter cam. Quote Link to comment Share on other sites More sharing options...
standardthread Posted July 12, 2022 Share Posted July 12, 2022 16 hours ago, Clive said: for the clutch you can use a dolomite 1300 clutch plate. These are like elephants' eggs to find, same size as the Spitfire etc but different splines. I've driven Heralds for decades with no problems with the three rail gearbox and re-built a few boxes. I have also driven Dolomites for the last five years and had trouble with the gearboxes (single rail). The first 1300 Dolomite I had the box went and I did a straight swop with a box from a 1500 Spitfire, I didn't even attempt a box re-built, it looked more complex but I kept it for spares. The flywheels between the 1300 and 1500 Dolomites (1500 Spitfire and MG) are apparently significantly different between the Dolomites. The Triumph Dolomite Club site goes in to detail if you do a search). If it were me I would keep the three rail original box, or look around for a MkIV box with OD, it's straight swop, I've done it on my Herald Estate and the saloon apart from the needed propshaft change. Then sell the parts you break from the 1500 Spitfire Quote Link to comment Share on other sites More sharing options...
DennisA Posted July 18, 2022 Share Posted July 18, 2022 If anyone is interested I have a single rail tranny with the J type overdrive they need to be reassembled with the new parts I bought for the rebuild. I’m doing a 5 speed conversion. Dennis Quote Link to comment Share on other sites More sharing options...
Dogsbody47uk Posted November 17, 2022 Share Posted November 17, 2022 Fit the 1500 flywheel and clutch. Spacers are needed in the fly wheel mounting holes so that the smaller original bolts can be used. Doing this means that the larger 7 1/4" clutch can be used and it has the correct number of splines to match the J type input shaft. Spacers can be obtained from Canley Classics or Rimmers, I believe. Quote Link to comment Share on other sites More sharing options...
glang Posted November 17, 2022 Share Posted November 17, 2022 Why bother when the correct clutch plate is easily available (see previous thread)... Quote Link to comment Share on other sites More sharing options...
Dogsbody47uk Posted November 17, 2022 Share Posted November 17, 2022 Hi Glang. Personal choice because I later swapped out my 1296cc for a 1500 Spitfire engine so no need for any further mods. Cheers, Dave Quote Link to comment Share on other sites More sharing options...
glang Posted November 17, 2022 Share Posted November 17, 2022 Each to their own of course but I think Amy's mk3 should keep its 1300 engine! Quote Link to comment Share on other sites More sharing options...
RobPearce Posted November 17, 2022 Share Posted November 17, 2022 If my Mk3's engine had been salvageable it would have kept it. Even then, it probably would have got an FD engine to replace it, had I not already had a spare 1500 (with Herald flywheel and clutch) lying around. I definitely wouldn't have gone for a single-rail gearbox, but that's personal preference. Quote Link to comment Share on other sites More sharing options...
glang Posted November 17, 2022 Share Posted November 17, 2022 I know what you mean but 3 rail OD gearboxes in good order are getting really hard to find these days so I think Id rather have a gamble with a single rail as they are a stronger box, have J type OD, newer and produced in relatively large numbers.... 1 Quote Link to comment Share on other sites More sharing options...
Amy Wade Posted November 17, 2022 Author Share Posted November 17, 2022 6 hours ago, glang said: Each to their own of course but I think Amy's mk3 should keep its 1300 engine! My Mk3 will be keeping the original 1300 engine. I'll use the 1500 flywheel as I have a NOS Ferodo clutch kit. Quote Link to comment Share on other sites More sharing options...
.thumb.jpeg.b15b81ef10abeea1c3039ae03c4a9f3a.jpeg)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.