gruntus Posted September 20, 2006 Share Posted September 20, 2006 Gents your advice please (be nice ), I have a C plate 90 2.5 TD that I have stripped down ready to rebuild on a galv chassis and bulkead. This motor is going to eventually replace my Disco for the forseeable future and hence want to do it all properly. I have wayed up the pros and cons of using the original 2.5 TD for now and then fitting a 200tdi in the near future and I also want the luxury of power steering (it nearly killed the mrs in my last series 3). I had a brain wave when I realised that I could actually use my 200tdi disco as a donor car (its only worth about £1500 and steadily having to weld it more for its MOT's). The engine was rebuilt about 25,000 miles ago with a new turbo and radiator so I know it is a good item mechanically to drop in the 90. I know the engine and gearbox should fit (some great articles in the tech archive) and that the power steering should also be fine. I also found out the radiator mounts on the chassis have to be shaved off and lowered for the disco combined unit to fit correctly. What I would like to know is what else I can use on the 90 or what problems I might have? I have been told I should be able to swap over the axles (and get disks all round) as long as I use the master cylinder from the disco however I don't know if this a worthwhile exercise (advice please). I have been told that cruising speeds/economy will also improve with fitting the Disco gearbox as the gearing in the transfer box is taller than the 90 and I will be using the disco wheels already fitted. One last thing...... The next (first) step in the project before getting excited with the mechanical stuff is the boring, laborious job of prepping the panels ready to paint. I decided to buy a new gun when I was informed that the industry is going over to water based paints and that HVLP guns are now the choice. Anyone have any advice at all? I have mostly used cellulose and one shot with two pack however I felt a bit out of date when confronted with the waterbased paints and not sure what to ask or what gun to get (a lot of choice with a range of prices). If anyone is interested or think its worthwhile documenting let me know. As always thanks for your advice Grant Quote Link to comment Share on other sites More sharing options...
western Posted September 20, 2006 Share Posted September 20, 2006 Use all the bits as identified in the Tech Archive thread you mention, you can use your Disco axles on the 90, their just a straight swap, don't think anyone on here has used the Disco master cylinder, as some have just had the axle on it's own. you can use the Disco maingearbox & transfer box too or leave the 90's gearbox's in place & just swap the engine over. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted September 21, 2006 Share Posted September 21, 2006 Cellulose paint is being phased out, not sure about twin pack epoxy paints though. The new water-based vehicle paints are damned expensive in the smaller quantities you will require to do a single vehicle. If you are going to use a flat colour, then buy it now, and then use your current spray gear. The 200TDi engine and disc brake conversion are well worth it. Les. Quote Link to comment Share on other sites More sharing options...
michael calvert Posted September 21, 2006 Share Posted September 21, 2006 think this is the link for the tech archive disco into a 90 Quote Link to comment Share on other sites More sharing options...
gruntus Posted September 21, 2006 Author Share Posted September 21, 2006 Thanks Les/Ralph Les, can you confirm if I need to swap over the master cylinder from the Disco for the axle swap (disc brakes) or if the exisiting master cylinder on the 90 will be ok? Cheers again guys. Grant PS this forum has changed my life!! Quote Link to comment Share on other sites More sharing options...
gruntus Posted September 21, 2006 Author Share Posted September 21, 2006 Ooops one more I forgot to ask.... If I change over the axles engine and gearbox from the Disco and the Disco being a longer wheelbase will the 90 propshafts still fit okay or does anything needed "adjusted"? Grant Thanks for the link Michael Quote Link to comment Share on other sites More sharing options...
Les Henson Posted September 21, 2006 Share Posted September 21, 2006 I don't know that you need to fit the Disco Master cylinder. I would have thought that the 90 master cylinder would be adequate for a rear disc conversion. I don't know enough about it to say for definite I'm afraid. As fitting the rear axle and changing the master cylinder are two seperate operations, I would suggest you fit the axle and see how the brakes operate, then decide. Les. Quote Link to comment Share on other sites More sharing options...
will_warne Posted September 21, 2006 Share Posted September 21, 2006 Grant, I think the reason you've been told you need to run a Disco master cylinder is that they, and RRCs, use callipers with double brake lines on the front axle. I can't remember what the systems called, though, as it's not dual circuit which is the front / rear split system. You've got a couple of options with axles; the first is to only change the rear axle (giving discs all round) and you're mastercylinder can stay, the second is to change both axles and then fit the original front calipers from the 90 to the disco axle. the only other thing you'll need to do is play arround with some of the braketry on the top of the swivel. Option 3 is to use the disco axles and mastercylinder. I'm not a great expert on discoveries so I'm not sure if the mastercylinder'll bolt straight up to the bulkhead, whether there'll be clearence issues with the bonnet etc. My chosen opition would be to go with either 1 or 2 depending on the condtion of the differant axles. My guess is the original 90 one will be better as disco diff pans have a habit of rotting through. Unless its going to be used seriously off road there's little benifit in weighting up the pro's and cons of each varient of rover axle to see which suits you. I hope that's of some use, Edited to add, yes, as long as you keep the gearbox in the original position (ie keep the original mounts) then the original propshafts are fine. As far as fitting everything in it shouldn't be too much of a problem. The gearboxes are essentially the same (both LT77s although the disco one may well be an LT77S by '92 which is considerably better). You're only headache will be the exhaust downpipe as there isn't a lot of clearence. Appart from that it should all fit together nicely. Oh, I'd also think about selling the radiator and intercooler from the discovery and finding a defender frame, intercooler and rad at Sodbury as it'll mean there's no chopping arround required. You could even use it as an excuse to upgrade the intercooler, and or, the rad at the same time. Quote Link to comment Share on other sites More sharing options...
JST Posted September 21, 2006 Share Posted September 21, 2006 all as above. i have a 90 with rangie rear disc and run the std 90 M/c as i didn on previous 110 and most of mates also do with this conversion. Where did you hear you need to change them over? disco t box is 1.2, defender td one is 1.4. def wil be quicker with the higher ratio disco box but if you live in a hilly area, tow alot then may not be ideal solution. if you do alot motorway miles then prob worth changing them over. Check mainsahft G box wear. I would leave the G and T box of exisitng def and fit disco engine to it. you can always change them later if you wish to make use of the 1.2 disco T box. use 90 props. with either g box and t box in original position it will al fit. may need to change the drive flange on the disco axles noses as i think they are 3 holed not 4, easy job, rest will all go together. Quote Link to comment Share on other sites More sharing options...
gruntus Posted September 21, 2006 Author Share Posted September 21, 2006 Hi Will/James, Excellent information thanks. Option 1 sounds the best (I like to keep things as simple as possible) and I am fairly certain the Disco (93) has an LT77s gearbox. With regard to the downpipe from the head I did find a link to a company who made the item but were approx £80 (www.steveparkers.co.uk). I will speak nicely to my old man and get him to try and knock me one up.... Unfortunately I live in Scotland so a trip to Sodbury to source the correct radiator/intercooler frame is a bit too far to go........ I would like to upgrade the intercooler at a later but would like the motor to be up and running for a while before upgrading (not to mention keeping the budget below the wifes radar! ) With regard to an intercooler upgrade I don't have a problem fitting the DIY kit but have never adjusted the fuel pump before, is there a rule of thumb for adjustment as obviously I don't want to break the engine!! Regards Grant Quote Link to comment Share on other sites More sharing options...
Ivan Posted September 21, 2006 Share Posted September 21, 2006 Info and pictures of fuel pump tweeking can be found here Ivan Quote Link to comment Share on other sites More sharing options...
gruntus Posted September 21, 2006 Author Share Posted September 21, 2006 Thats a great post Ivan thanks, It would be a great post for the Tech Archive.... Grant Quote Link to comment Share on other sites More sharing options...
will_warne Posted September 21, 2006 Share Posted September 21, 2006 Grant, you can do anything to fueling as long as the EGT (exhaust gas temperature) stays sensible. Arround 750 degrees C is as far as you want to go for a reliable, road engine. Quote Link to comment Share on other sites More sharing options...
Diff Posted September 21, 2006 Share Posted September 21, 2006 You may not be able to use the disco gearbox as it is. The disco LT 77 has a much longer bell housing and input shaft than the defender version. This will put your engine further forward(like a 300tdi is fitted). This will mean moving the engine mounts forward on the chassis(cutting and welding). Also, I am pretty sure that the gearlinkage positions on the disco box are different, so will not line up with your current gearbox tunnel openings. I'm sure someone else will be able to confirm this. Regards, Diff Quote Link to comment Share on other sites More sharing options...
JST Posted September 21, 2006 Share Posted September 21, 2006 ref the intercooler and rad etc use the disco one chopping around is not alot of work see my thread and Les's in tech archive mins work rather than the hours if your going to mkae up your own downpipe. i would go for the steve parker option. Quote Link to comment Share on other sites More sharing options...
B reg 90 Posted September 21, 2006 Share Posted September 21, 2006 I fitted a disco rear axle to my 90. Just pumbed in the brake line and drove. But without the pressure reducing valve in the rear brake line that disk braked 90's are ment to have the rear end would lock up on heavy braking - not the best handling characteristic. I then fitted 110 calipers to the front to adjust the brake balence as the 110 units have bigger pistons. The braking is now perfect and the 110 calipers have reduced the pedal pressure required. Adrian Quote Link to comment Share on other sites More sharing options...
white90 Posted September 21, 2006 Share Posted September 21, 2006 Thats a great post Ivan thanks,It would be a great post for the Tech Archive.... Grant Different version already in our tech archive. Ivans link is a decent one too as pics are included. maybe a "how to henson" opportunity Quote Link to comment Share on other sites More sharing options...
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