Thread: RRC 1990 ls1, t400 & LT230 conversion

Most of time the drivetrain for those two models are interchangeable. You shouldn't have to change anything to swap the Borg Warner TC for the LT230. ( The BW TC should bolt up to the adaptor plate fine - it's the same as the LT230 )

A tip: Give the LT230 some new bearings and seals ( input/output/intermediate) and maybe give the centre diff some new shims. Also grab a cross drilled input gear (As the 85 isn't and lack of lubrication wears the gearbox output shaft splines)

Thanks for your reply langy,

I will be calling marks4x4 and have a chat with him today about using the borg warner TC.

If not i will be using the LT230R from the 85.

Is anyone able to tell me if there are any differences between the 85 to the 86-89 models?

Is there anything i should be looking out for during the conversion?

Thanks

Adrian

If the LS1 is going to put ot any reasonable amount of Power ,plus 220KW , then Weld up the center diff , same as Tebone has done with his Blown 383. Then look at getting the front/rear diffs strengthened !! yeah , Centers,axles,CV's , the 10 spline jobbies you got wont be lasting long with that sort of power !!!

Hi 400HPONGAS

When thing break then they will be changed. LS1 is stock.

I called MArks4x4 and they have no idea about if the borg can bolt upto the adapter.

Can someone confirm that the input and bolt patern of the borg and the LT230 is the same. If so i wont worry about the swap just yet and just keep the borg until it breaks.

OK ,you were only fishing ! ,I think Langy has allready answered your question re the Lt230 .you would be better off deciding what ratio you need in the transfer case and then building one to suit.

hey 400,

Yes he did i mis read his post, thanks.

OK so for now i will be keeping the borg in to get all the conversion of the LS1 working. I have a 1985 transfer to use but my research tells me that it is an LT230R not T. This being hard to get parts for as it is a roller bearing design not a taper bearing.

Can someone confirm.

Ok then as 400HP said, ratios, damn where to start. I have a 3 speed turbo 400. borgwarner TC, 33's and standard diffs.

Once we start the pulled down in the next couple of weeks i will post a new thread under projects.

Cheers

Adrian

yeah , you will have a big problem going down steep hills with the T400 gearing , so perhaps the Defender 1.4 ratio may better suited , but then theres the cruising at 110KPH and only 3 speeds so maybe a 1.003 out of a 84/85 torqueflite .then maybe a middle ground 1.222 which is the most common (RRCs 1986-1988 and most D1's 92-98) So is it fuel economy or off-road performance .Hope you specify a nice tight convertor (say 80% at 1000RPM )or a big brake upgrade .

so at the moment with the borgs it has a 1.2 ratio. the 85 then has the closer to 1:1 ratio so maybe using that and re-building with a high low range gear might be the trick.

Yeah i have to find a torque converter still. The one i have is a 3.5k. Do you know of any going for t400 and LS1?

BTW this is not a daily although we do need to travel to the offroad playgrounds which is alot of 100km zones.

Also i am looking for a fuel tank. Either stock or cell. Any ideas?

Cheers for your help.

Adrian