Jump to content

v8/auto conversion


gelf

Recommended Posts

been offered a v8 3.5 efi....... as ive decided to go down the v8 route..... it only gets used now and then so i think i can cope with costs.

the engine comes with a 4sp auto box and i was just wondering how much of a headache it would be to fit them both......... as im not the worlds best mechanic.

my box is currently a LT77.

graham

Link to comment
Share on other sites

I'm not the worlds best mechanic either and I've just stuck a V8 and ZF in to a 90, ok it's not on the road yet, but that's besides the point :rolleyes:

You have an LT77 and IIRC a 2.5 diesel at the moment. So you need to move the engine mounts and the gearbox mounts will bolt up to the existing mounts when the LT77 mounts are removed. You'll need to chop the seatbox and tunnel about a bit to fit it in, I got away with this as mine was an original V8 90 with an LT85 and hence the much bigger transmission tunnel anyway. The rest it mainly spanner work.

Before starting out I knew nothing about auto's, torque converters, etc, but it's not that difficult really. I bought RR rolling shell complete with engine and gearbox so I got all the bits needed (see below), carefully split the box from the 3.5EFI engine and mated it up to my 4.2 and then fitted to the 90.

You will need.....

ZF box complete with:

dip stick / filler tube

kick down cable and assembly

shifter lever and cable (very expensive to replace)

torque converter

drive plate

boss that connects drive plate to crank

gearbox mounts, both sides including the one that bolts to the LT230 (I had to take a little nick out of the off side mount to clear a seat box mount)

gearbox wiring loom for start inhibit and reverse light

transfer lever and mounting

See why it's easiest if you have the complete RR to raid for bits rather than buying a box off the floor.

Also need to fit an oil cooler, you can use the RR one or fit a mocal type, which is the route I'm taking due to space limitations.

Worth doing an oil and filter change on the box as a minimum IMHO.

You will need a new coupling shaft from Ashcrofts if you want to fit a transfer box with a cross drilled input gear. The 1.22 ratio box that will most likey be with the ZF may be a bit high if you are on 35's.

Obviously you have fuel, electrics, cooling, etc to sort for the V8 if you are converting from a diesel.

Erm I think that's it, well it's all I can think of at the moment.

Link to comment
Share on other sites

have fitted an 8 before , just the autobox im unsure about :unsure: ............... let us know when youve finished, and wether its worth it.

also a little concerned obout engine braking etc when off roading on steep decents.

Link to comment
Share on other sites

Could be a bit yet before it's finished, work on that project has stopped for the winter while work on the house is carried out :unsure:

I've not used an auto off road in anger myself yet, but speaking to those with autos seeing them in action was enough to convince me it's the way to go. Low speed control and winch assist with out the need for an under drive, kinder on the drive train, on balance I think the pros out weigh the only con of lack of engine braking, but you still have brakes you can apply, with care. More and more people seem to be changing to auto for serious off roading.

Link to comment
Share on other sites

Could be a bit yet before it's finished, work on that project has stopped for the winter while work on the house is carried out :unsure:

Come on Mark, i thought the 90 would be back on the road well before the Tomcat makes a appearance :P , Im deeply regretting selling it now

why I why did i get drunk that nite & decide to build a new one :blink:

Link to comment
Share on other sites

I thought it'd be back on the road before the tomcat too. I sometimes think I should have stuck the manual box back in rather than faffing around with the auto conversion, it'd probably have been done by now. Oh well, only one more room to decorate and I can get back to the 90 full time, might be warm enough for working outside again by then :rolleyes:

Once the tomcat's finished I'm sure you won't regret it. I thought I should have kept Alf so i had something to use while the 90 was being sorted, but then it'd never get finished :ph34r:

Link to comment
Share on other sites

where does the engine sit?................ when i fitted an 8 to the lt77 it was along way back......... aslo would my transfer box fit on a ZF auto?...as the ratio would be better? ;)

Link to comment
Share on other sites

A long way forward, as in the standard V8 90's. If your V8 was a long way back I assume you fitted it to a 4 pot LT77 with an adaptor plate rather than using the much longer V8 LT77.

Here's a couple of shots showing mine. That's mounted using the ZF brackets from the donor RR on the original gearbox mount chassis holes, which I think are in the same position on all 90 chassis. The engine sits on the original engine mounts, it's an factory V8 90 with an LT85 originally.

red23.jpg

red28.jpg

Yeh, any ratio LT230 can be fitted.

Link to comment
Share on other sites

V8/ Auto,, worth all the effort guys,, Ok I bought with it all done :) , but would not want to go back to a manual box !!,,

On std ratio's ?, and yes,, downhill on 35" simex, is "interesting", but as Mark points out,,brakes are fitted, :P ,,

The auto,is very good on slow rock work etc,, first real time i used, was the river bed at seven sisters, the auto made it so easy, with the V8 to back it up :D

Link to comment
Share on other sites

V8/ Auto,, worth all the effort guys,, Ok I bought with it all done :) , but would not want to go back to a manual box !!,,

On std ratio's ?, and yes,, downhill on 35" simex, is "interesting", but as Mark points out,,brakes are fitted, :P ,,

The auto,is very good on slow rock work etc,, first real time i used, was the river bed at seven sisters, the auto made it so easy, with the V8 to back it up :D

Totally agree. Auto gives sooooo much control and you can get engine braking back although it will hurt the wallet. I'm still very much learning to use mine but I love it.

Link to comment
Share on other sites

do you still keep the original props as ive not long had some new wide yoke ones? :(

Dunno mine didn't have props when I bought it. Has a TD5 front prop fitted now and that seems ok. I'm after a V8 90 rear prop for the back.

Link to comment
Share on other sites

Having the larger LT85 tunnel meant mine didn't need any modification to fit the ZF and I've simply mounted the auto shifter with a bracket to the seat box, not quite solid enough for my liking so will have to brace the bracket, cubby box will fit in the center over the hole the cable will pass through.

red31.jpg

Link to comment
Share on other sites

This was how I did mine many moons ago......

Workinprogress009.jpg

Workinprogress026.jpg

Workinprogress011.jpg

Workinprogress029.jpg

Got an LSE console from Sodbury and used ally angle for the frame and brushed ally for the top and the CB housing. The window switches got used for the winch controls.

Well this is mine, which i belive Dan did (his post copied from here )

Link to comment
Share on other sites

Well this is mine, which i belive Dan did (his post copied from here )

That does look very tidy mine is a little more basic but I do pressure wash my truck inside and out after every outing so I would posibly wreck it.

I fitted the 4.2 auto to a mate's 110 and found it very easy just conecting all the cooler lines up was a pain as it gets a bit conjested under the right hand side of the crank pully with athe auto cooler pipes and then the engine oil cooler pipes as well then on mine all the winch power lines come through there as well. The Auto istselfe was easy but I did not split it from the V8 and I had the LSE Braker just outside the workshops ready to nick any bits needed.

My 90 is a 4.2 Auto from a LSE.

ixi15.JPG

Link to comment
Share on other sites

Guest diesel_jim
like the look of the nas center console that Will has used........... just alittle pricey

so if anyone has piccies of home made ones lets see them.

thanx

gelf

Frogs island do a NAS copy of the center console. £295, but still considerably cheaper than the £600 odd that LR would fleece you for! B)

Thats what i'm going to stick into my 90 ASAP.

Link to comment
Share on other sites

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy