trojan Posted September 7, 2006 Share Posted September 7, 2006 i have a question for someone who knows about gear ratios and the like , cos i can't work it out i'm in the process of changing the gearbox on my 90 ( lt77 ) and i have the choice of 3 transfer boxes and i don't know which one to use . i have a 90 with a discovery 200tdi conversion , a standered lt77 gearbox , standered diffs , but i'm running 33-1250-15 mt tyres . fitted to it now is a disco 1.222 transfer box ( 28d ) , but i have a 22d- 1.410 and a 13d- 1.410 . i realise the last two are the same ratio but why the different model numbers ?? as it is now with the disco 1.222 it does seem a little high geared at low revs but it pulls like a train when the turbo wakes up . i'm not after f1 performance , ( if i was i would'nt have a landrover ) and i'm not bothered about speedo readings ( we can sort this out later ) . but i would like a good compromise if possible . and can somebody explain what the numbers mean cos i'm not sure !!! . it's a bit like sheet music , i know what it is but i don't know what it says . also , got me one of those x brake disc handbrake thingy's today B) B) and boy does it look good , i don't even care if it works or not i have to be honest and tell you that i almost licked it doe's that make me sad or what !!!!! Quote Link to comment Share on other sites More sharing options...
Mark90 Posted September 7, 2006 Share Posted September 7, 2006 A 1.4 ratio box is standard on a tdi defender. Yours is as you say a bit overgeared with the 1.222 disco high ratio transfer box and 33" tyres. Remember teh 1.222 ratio transfer box was designed fro 29" tyres and the 1.4 box for 31" tyres. I would fit the 1.4 box it it was me, although some people like the overgearing to gave more relaxed cruising at the expense of acceleration/towing ability. Note that the low range will be unaffected, both boxes have the same low ratio. Quote Link to comment Share on other sites More sharing options...
western Posted September 7, 2006 Share Posted September 7, 2006 different model number -- 13D,22D for different versions/engine combinations. Quote Link to comment Share on other sites More sharing options...
trojan Posted September 7, 2006 Author Share Posted September 7, 2006 different model number -- 13D,22D for different versions/engine combinations. it sounds like i may be better off dropping back down to the 1.410 then , does it matter whether i use the 13d or the 22d i don't suppose theres any gear difference then . Quote Link to comment Share on other sites More sharing options...
landmannnn Posted September 7, 2006 Share Posted September 7, 2006 Having used both with 33" tyres (albeit with a low power V8) I found 1st high was too low on the 1.4, I normally/often pulled off in 2nd. With the 1.22 first gear is just about right although the very high 5th is more like an overdrive, I just use 1st to 4th unless on motorways. I never do any towing. Quote Link to comment Share on other sites More sharing options...
trojan Posted September 7, 2006 Author Share Posted September 7, 2006 Having used both with 33" tyres (albeit with a low power V8) I found 1st high was too low on the 1.4, I normally/often pulled off in 2nd. With the 1.22 first gear is just about right although the very high 5th is more like an overdrive, I just use 1st to 4th unless on motorways. I never do any towing. i agree , its' the same with with the 200tdi don't use 5th gear that much and running round town i just need 3rd and occasional 4th , it doe's pull well though when it's warmed up probably matches the engine revs better when the turbo kicks in . how doe's your speedo match up to your actual speed have you checked it ??? Quote Link to comment Share on other sites More sharing options...
landmannnn Posted September 7, 2006 Share Posted September 7, 2006 i agree , its' the same with with the 200tdi don't use 5th gear that much and running round town i just need 3rd and occasional 4th , it doe's pull well though when it's warmed up probably matches the engine revs better when the turbo kicks in . how doe's your speedo match up to your actual speed have you checked it ??? My speedo did under read, I then put bigger tyres and lower diffs on and it is now about right. I am not a great fan of close(ish) ratio gearboxes, my last road car was a 6 speed - drove with one hand on the wheel and the other on the gearlever. Quote Link to comment Share on other sites More sharing options...
trojan Posted September 7, 2006 Author Share Posted September 7, 2006 i know what you mean about gear changes i drive wagons for a living and i do get sick off changing gears all the time , i tend to keep my landrover in 3rd around town when i can and as long as i keep the turbo spinning its ok . my speedo seems ok up to about 50 and then its way out, but i think the cable is knackered so its having a new one aswell . Quote Link to comment Share on other sites More sharing options...
Andy Posted September 7, 2006 Share Posted September 7, 2006 im running 32" tyres on a disco with the original diffs/tbox my speedo reads 9% low. im considering a 1.4 tbox when i go for 33s. not going to hunt for one though as it feels it will pull it ok. just when my rattling center diff gives up i may well look for a 1.4 box. my engine is quite well tweaked though & i can now climb hills in 5th that my car needed 4th for when it was standard. Quote Link to comment Share on other sites More sharing options...
trojan Posted September 7, 2006 Author Share Posted September 7, 2006 im running 32" tyres on a disco with the original diffs/tbox my speedo reads 9% low. im considering a 1.4 tbox when i go for 33s. not going to hunt for one though as it feels it will pull it ok. just when my rattling center diff gives up i may well look for a 1.4 box.my engine is quite well tweaked though & i can now climb hills in 5th that my car needed 4th for when it was standard. sounds like i've got basically the same running gear as you then ,and i'm a few hundred kilos lighter , it keeps up with my mates 300tdi defender ok so maybe it's just me i've considered a pump tweak but i'll leave that till i find someone i can trust to do it . Quote Link to comment Share on other sites More sharing options...
Andy Posted September 8, 2006 Share Posted September 8, 2006 pump tweaks are easy enough, just do small amounts at a time & keep a record of what you've done for if you need to reverse it. ive got a tweaked pump, full width intercooler & running 18psi of boost (stock is 12psi). oh & it runs on 60% SVO. with any TDi i owned now i would do the most basic pump tweak, wind the smoke adjuster screw on the top of the injection pump in a couple of turns. you get so much more power before the turbo is fully working its a much nicer engine to drive afterwards. i can use 5th from an indicated 30mph on the flat nowdays. its not quick but it doesnt seem to struggle over it. Quote Link to comment Share on other sites More sharing options...
mwncidur Posted September 8, 2006 Share Posted September 8, 2006 In my 110 i have just put a 200 disco and a defender r380 but have kept the 1.6 transfer box. its ace! flat out is about 76mph, that is with 205 fedimas. but i do a fair amount of towing so the low gearing suits me. try a 1.4 and see what you think, you can always change it! Quote Link to comment Share on other sites More sharing options...
trojan Posted September 8, 2006 Author Share Posted September 8, 2006 pump tweaks are easy enough, just do small amounts at a time & keep a record of what you've done for if you need to reverse it. ive got a tweaked pump, full width intercooler & running 18psi of boost (stock is 12psi). oh & it runs on 60% SVO.with any TDi i owned now i would do the most basic pump tweak, wind the smoke adjuster screw on the top of the injection pump in a couple of turns. you get so much more power before the turbo is fully working its a much nicer engine to drive afterwards. i can use 5th from an indicated 30mph on the flat nowdays. its not quick but it doesnt seem to struggle over it. i may have a go with the pump tweek at some point , sounds like it should be better . the trouble is i get a bit paranoid about things like that i've changed the air filter and replaced it with a pipercross cone thing , (ya know one of them boy racer things ) and that made a big difference on it's own , but i may have to rethink that because i'm starting to go greenlaning and i need a snorkel ,don't like the idea of a big sponge under my bonnet , i quite fancy the full width intercooler , which one did you use ? and where did you fit it . Quote Link to comment Share on other sites More sharing options...
Andy Posted September 8, 2006 Share Posted September 8, 2006 full width intercooler from www.straightforwardsupplies.co.uk fits nicely infront of the rad. you need to make brackets & lengthen the pipes to suit. brackets = bent bit of plate in my case & some 2" zorst pipe inserted in the middle of the original hoses completed the package. you can get insert filters to fit the original airboxes, that'd keep your improved performance & allow a snorkel. my theory on the pump tweaks was i aint gonna kill the thing with one turn of a screw. so i just kept a record of what i turned so i could put it back if i didnt like it. took me about 2 weeks of fiddling before i settled on how i liked it. just for info when i turned the boost up i had to put the diaphram almost back to stock, wind the smoke adjuster right out, wind the max power in and i've never found any advantage to moving the starwheel. Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted September 8, 2006 Share Posted September 8, 2006 If you're concerned about the level of performance you can get with pump tweaking etc, an EGT gauge is a good investment to protect your engine (so long as you appreciate the limitations of the kit). Quote Link to comment Share on other sites More sharing options...
trojan Posted September 10, 2006 Author Share Posted September 10, 2006 If you're concerned about the level of performance you can get with pump tweaking etc, an EGT gauge is a good investment to protect your engine (so long as you appreciate the limitations of the kit). whats an egt gauge , am i right in assuming its some kind off emissions test thingy ??? and i'm gonna swap my transfer box over to the 1.410 and see what that doe's , as someone has already said i can always change back . ohh , i fitted my xbrake handbrake the other day and it was probebly the quickest and most simple job i've ever done , looking forward to not having problems with my handbrake anymore . Quote Link to comment Share on other sites More sharing options...
western Posted September 10, 2006 Share Posted September 10, 2006 whats an egt gauge EGT = exhaust gas temperature gauge, it to monitor the exhaust temp leaving the turbo's turbine/engine so that you don't melt the turbine blades/damage the engine, more use on a diesel engine thats had it's injection pump tweaked & larger intercooler. more info on how to fit one here Quote Link to comment Share on other sites More sharing options...
trojan Posted September 10, 2006 Author Share Posted September 10, 2006 EGT = exhaust gas temperature gauge, it to monitor the exhaust temp leaving the turbo's turbine/engine so that you don't melt the turbine blades/damage the engine, more use on a diesel engine thats had it's injection pump tweaked & larger intercooler.more info on how to fit one here cheers western , but i think i'll leave the pump tune for now , the reason is i'm not sure what mileage is on this engine and i don't really need it to be better than it is now . one for the future though . and just out off interest doe's anybody know what the egt kit cost's ??. Quote Link to comment Share on other sites More sharing options...
western Posted September 10, 2006 Share Posted September 10, 2006 don't think there's a 'kit' as such, most of the guys who have fitted these gauges have built it up from a selection of parts they have decided on. Quote Link to comment Share on other sites More sharing options...
SOA 93 Posted September 10, 2006 Share Posted September 10, 2006 don't think there's a 'kit' as such, most of the guys who have fitted these gauges have built it up from a selection of parts they have decided on. EGT kits can be had from these people, http://www.turbobits.co.uk/acatalog/digita..._egt_gauge.html Andy Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted September 11, 2006 Share Posted September 11, 2006 Mine was £120 inc postage from Thermoman, search the archives for his (Australia-based) website. Quote Link to comment Share on other sites More sharing options...
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