Gearbox options for V8 in a SWB Series ???

[henrycrabbe]

Hi Guys,

I need your help. I'm just trying to get my head around what gearbox to use in my Series 2a 88 when I drop a V8 in it. As far as I know, I have the following choices:

• Series 4 speed with adapter ring for the V8
  
• LT77 Short (2.5) bellhousing with adapter ring for the V8
  
• LT77 with SD1 V8 bellhousing
  
• LT95 4 speed with 101 style short V8 bellhousing
  
• R380 with Rangerover P38 V8 bellhousing
  

Now I'm not concerned about using permanent four wheel drive (I have a stage 1 V8 front axle if I need it) so no problem with the LT230 or LT95. I'd like full synchro with either 5 speed or 4+ overdrive that can take the power & torque of the V8 reliably. The thing that concerns me is the overall length and fitting it into an 88 without resorting to a radically short rear prop, and yes I do want to keep the set-back series front grille!

Can anyone shed any light on their experiences with any of these combinations? I'm not even sure if the R380+P38 bit is possible, but looking at pictures of the P38 transmission (on ebay etc) it seems to have a really short bellhousing that will go straight on the V8. So will this bellhousing swap onto a Defender/Disco transmission?

Your thoughts would be appreciated...

Cheers, Steve.

[Rich_P]

All I know is that people have run Series boxes with 3.5 engines with little trouble.

[missingsid]

I have been running a Series1 V8 on a Series 1 G/Box and T/Box for years ands my mate even longer.

We both have broken Layshafts but still driven home in top (4th). Actually I was driving his Series1 when his box broke.

Both times I was driving slowly.

I spoke to Dave Ashcroft by email about an LT95 conversion but be siad it would be very long and an R380 was a better choice.

See Ashcrofts web site.

Marc.

[FridgeFreezer]

I ran a 3.9EFi on a Series box with overdrive & 3.54 diffs and it lived long enough, but it's not a great combo IMHO, overdrives whine like hell and the box is designed for 62bhp not 162. Also the ratios are all to cock whichever way round you slice it - with Series diffs it's too low on the road, with 3.54 diffs it's too high in low box, and the high-ratio transfer box etc. cost several times what an LT230 costs.

Reliability wise, it's entirely dependant on your right foot.

I now run a 4.6 in front of a late Range Rover Classic R380 & LT230. I've no idea about P38 gearboxes/bellhousings. I run an LT230 with 2WD conversion just 'cos I like donuts

You do not need CV's in your front axle to run permanent 4x4, it is smoother with CV's but many run with standard series axles & LT230's.

In a SWB, the length of the combination is going to be the limiting factor, combined with your willingness & ability to engineer around it. Your first step is to get the tape measure out and wave it at as many different combos as possible. I've seen V8+LT77+LT230 in an 80" so it's certainly not beyond the capabilities of modern science.

[Jon White]

I ran LT77 with 4pot defender bellhousing and an adaptor plate no problems. I run LT230 with permanent 4wd on the standard series front axle and have no problems.

I'm now running 200tdi, but the gearbox is still the same.

This is the best setup in a swb in my opinion. Rear prop ends up about 4 or 5" shorter but doesnt cause any problems, and mines got a hell of a lot of rear travel. R380 comes out even longer which will put the gear lever too far to the rear. You wont be able to run the factory V8 bellhousings for the same reason as its all just too long. (can get away with it in a 109 as the bulkhead is furher back.

I wouldnt entertain using an LT95 these days - parts are getting very hard to find, and frankly used ones are all knackered!

Jon

[henrycrabbe]

Hmmm, well that narrows my thinking...

I think the LT95 is out of the running, as was said they are getting rare and the 101 short version even rarer.

I currently have a 2a half-synchro box in the car, but it's not in good shape (jumps out of third and 2nd is pot luck!) and my missus would never master double de-clutching anyway, so it has to come out and I might as well drop a 5-speed in its place.

Looks like the LT77 shorty with V8 adapter is the way to go then, but I'd still be interested to know if the P38 V8 bellhousing idea would work? I think I'll contact Ascrofts and ask them.

Cheers guys,

Steve.

[RPR]

My advice is stick with the Series box. They are not very expensive in the UK and you can afford to recon one and keep it aside for switching in if you blow it up. I have run a 3.5 V8 and lately a 3.5/3.9 efi hybrid in front of a long abused SIII box turning 5.99:1 portal axles and 36" tyres, for two years and only just broke it this autumn while doing something stupid at highway speeds. As Fridge notes, you control your destiny. Treat it right and the Series box will hold up - and there are those who believe the IIA crash box is stronger than the SIII box. Converting to LT77 or R380 and LT230 will be more complex, take longer, and cost more than you imagined. Do the removable gearbox crossmember, keep a spare Series box on the side, and stick with the Series box.

[henrycrabbe]

your messing with my head now

I was all set on 5 gears and a choice of LT230 ratios to give me some sensible cruising speed without the engine revving its nuts off and/or me destroying the low range crawling ability. Hmmmm.

I need to do the gearbox x-member anyway, the current one is toast.

Thanks again, I'm off to lay in a darkened room....

Steve.

[moore101]

i run a 2a box and standard swb transfer box in my v8 lightweight. with 3.54 diffs it will cruise very happily at 70 all day long. thats on 235/85s and low 1st is slightly higher.

i use the vehicle for rtv trialling and i cant honestly say id have a problem with the gearing if it it were a standard rangie v8 (i have an sd1 cam and carbs so it revs nicely on road but doesnt have as much low down torque)

ive only broken one thing in the gearbox which was one of the 1st gears (took a tooth off somehow. was going up a quite nasty hill with a load of axle tramp and wheels lifting off)

on road it gets fairly harsh abuse. if gearchanges arent rushed then a standard series gearbox should be fine. and as previously mentioned. they can be picked up fairly cheaply to keep as a spare.

[henrycrabbe]

Thanks for your input guys

I'm gonna leave the final choice until I've got it stripped down and I'll see what comes along at the time. Before that I got to repair the rear half of the chassis with a new bit, but thats another story and probably won't happen too quickly

Cheers,

Steve.

[FridgeFreezer]

I'd have said it's harder to find a servicable Series box these days than an LT77, what with the thousands of rusty RR & Discos being broken as scrap. Also of note that Ashcroft and others no longer recon Series boxes but they do the others.

Obviously availability depends where in the world you are.

[Retroanaconda]

Thought they did?

http://www.ashcroft-transmissions.co.uk/part_113.html

Not cheap though. I'm sure it follows their other products in terms of good quality and service, but still a whole lot of money.

[FridgeFreezer]

Thought they did?

Must've re-started, I'm sure last I looked (admittedly years ago now) they didn't. I note the Series box costs about the same if not more as a recon R380, I know which I'd spend my money on.

[moore101]

help

im in a bit of a situation at the moment. my series 2a box is jumping out of fourth horribly since fitting a ground down input shaft to allow me to fit a meatier crank spigot bush. the bush works well and the box is quiter in all other gears so all is not bad. and it does cruise ok at 50mph in 3rd with rangie diffs so the vehicle isnt undrivable.

will a series 3 box go straight in as i have 2 sat at home (all i'll need to do is get input shaft ground down to size which shouldnt be too much of a problem i dont think)

something at the back of my mind is saying a series 3 clutch is a problem but not sure. maybe it was the problem of series 2 clutch release fouling that im thinking of.

[henrycrabbe]

If I remember right, the clutch slave cylinders are on opposite sides, otherwise its a straight swap. What gets in the way? only thing I can think is the exhaust ???

[Spongie2a]

series 2 and series 3 have a completely different clutch plate arrangement

SIII has a multi fingered plate 9.5"

SIIA has a 3 sprung centre which locates onto a metal bearing surface. 9"

some IIas have a multi fingered plate with a metal ring in the centre, this is the HD 9.5" SIIa clutch

the clutch slave is different and is on the drivers side (UK) for IIa and on passengers side (UK) for series 3.

HTH

[Phil Hancock]

What gets in the way when putting a S3 box in a 2a is the webs on top of the bellhousing crossmember, unless the 2a is a late one as then it has the S3 type crossmember.

[mickeyw]

In my 2A 88" I had a 3.5 carb engine mated to a standard SIII box and transfer assembly via a home made adapter plate.

I used the 9.5" standard clutch. You would need to re-drill the flywheel to suit the clutch, but it's not that hard to do.

I ran 3.54 diffs and 265/75x16 tyres, and cannot say that I had any gearing issues to speak of, could have done with another gear I suppose. It could easily do speeds that were quite scary in a leafer. On the flat 2nd gear was fine to pull away from standstill.

9 years use had passed without breakage before I sold the truck on. It is entirely down to how you drive, not to say that I was that gentle with it, but repeated chav racing won't do it much good.

[Spongie2a]

There is nothing stopping you using a series 3 box, just change the slave cylinder for SIII one and all is well.

[Spongie2a]

oh and RE: drilling flywheel, you shouldnt need to re drill flywheel at all as there should be a SIIa 9.5" flywheel or you could use the SIII flywheel

But then again I've never looked at a v8 too closely, my current 9.5" clutch did come off a 3.5v8 though and it was not re drilled...

[mickeyw]

oh and RE: drilling flywheel, you shouldnt need to re drill flywheel at all as there should be a SIIa 9.5" flywheel or you could use the SIII flywheel

But then again I've never looked at a v8 too closely, my current 9.5" clutch did come off a 3.5v8 though and it was not re drilled...

A clutch as used on a RRC is a LOT bigger diameter than a series one. You will not get a 9.5" clutch anywhere near the standard RRC fixing holes. That said, I don't know what the SD1 flywheel geometry was like. I do know SD1 flywheels were much lighter (anumillimum maybe).

[henrycrabbe]

but repeated chav racing won't do it much good.

That's the whole point isn't it

Alex, what flavour V8 are you running in your lightweight???

.

[FridgeFreezer]

RR clutch is 10.5", which adds a LOT of extra surface area but won't fit other than in a RR/Disco bellhousing.

[tacr2man]

I used hd diesel clutch friction plate , and 3.8 jag pressure plate, but you do need a strong left leg I used 2a box and 4.1 diffs with fairey o/d . and 235/85r16 mt . More than fast enough on road, and no lack of l/r torque. On road try and limit right foot travel in lower gears .

[moore101]

That's the whole point isn't it

thats what i thought as well! ive never raced boy racers in 106s and saxos, honest

Alex, what flavour V8 are you running in your lightweight???

its an engine allegedly out of a kit form 101. from memory i think the compression ratio made sense and put it at 8. something maybe, but the engine number doesnt tally with any records which has been fun with dvla.

the engine ran when i got it but badly due to a very very worn camshaft. i had an sd1 engine in bits which had a decent camshaft so that got swapped in along with the carbs on there which are autochoke jobbies.

the combination of the carbs and cam designed for high compression engine not low mean it runs a bit poor to be honest.

the other problem ive found is the engine is effectively now a car engine in a landrover, and as such the extra weight means its not quite what a v8 should be offroad. still got more torque than the original 2.25 and as long as revs are kept up a little bit then it picks up spot on and pulls perfectly.

think i will be putting series 3 box in next month unless i can sort the worn clutch sleeve. have the rest of the series 3 so have all the clutch bits i need.