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BMW P38 DSE engine into 1983 classic, possible???


orangemach5

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Hi all,

Ive been looking into repowering my 1983 rrc, it had a 3.5 v8. Ive converted it to a 3litre perkins turbo diesel, which is ok. The problem im having is with the 35" maxxis it doesnt pull as well as i would like.

Has anyone ever looked into putting the BMW diesel p38 dse lump in. On paper then engine looks great, 140hp standard and bucket loads of torque. Chip the engine and your looking at big increases! Ive seen a classic on ebay before with one fitted so it must be possible.

My main conern is the geabox, i have the 5spd long stick at the moment and would like to stick with it if poss. The manual versions of the P38 use the LT77 right? Can i fit the engine using a P38 bellhousing and clutch hydraulics etc to my box? I can probably get away with using the dse clutch aswell.

:-)

Any thoughts are much appreciated

Many thanks

Paul

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The manual box on a 38A in an R380.

I have no idea if that makes what you want to do easier or not.

"140hp standard and bucket loads of torque."

I don't know where that comes from.

Low down torque is NOT something the engine is noted for. Admittedly this is exacerbated by the fact that a 38A is heavier than a Classic. Note the manual box for the 38A diesel has a lower first gear than the manual box for a 4.0 38A.

1st ....................................3.321:1 ........................

Diesel models low first gear 3.692:1 .........................

For comparison with whatever you fit.

Overall ratio (final drive): . High transfer ... Low transfer

1st .....................................14.29:1 ........ 38.45:1

Diesel models low 1st gear .. 15.89:1 ........ 42.75:1

HTH

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Thanks for the replies!

Ive never had any goings on with R380's before, does anyone know whether the bellhousings are interchangeable between the R380 and the LT77???

The only other factor is whether the input shaft is the same length, splines different for the friction plate? shouldnt be a problem if they are as i could probably get away with using a HD Tdi friction plate.

Thanks again

Paul

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As David rightly says the horrible BMW 2.5 is not known for low down torque - why bother?You need a bigger unit like the Toyota 1HZ for your application.

My main reason for looking into the bmw is that landrover in theory have done the conversion work (if i can mate the r380 bellhousing to my lt77!!!)

When i put the perkins in it ended up costing me £300 to get a custom clutch made etc and the end result wasn't what i wanted. I was led to believe the bmw was reliable, any problems i should know about?

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My main reason for looking into the bmw is that landrover in theory have done the conversion work (if i can mate the r380 bellhousing to my lt77!!!)

When i put the perkins in it ended up costing me £300 to get a custom clutch made etc and the end result wasn't what i wanted. I was led to believe the bmw was reliable, any problems i should know about?

Why not use a P38 R380 in place of your LT77? That way, the clutch remains a standard item.

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Why not use a P38 R380 in place of your LT77? That way, the clutch remains a standard item.

Will it fit in place of the lt77 without too much grief though? Will my lt230 butt straight to it, the transfer box hangs on the wrong side on a p38 but does it still bolt the same?

cheers

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My main reason for looking into the bmw is that landrover in theory have done the conversion work (if i can mate the r380 bellhousing to my lt77!!!)

When i put the perkins in it ended up costing me £300 to get a custom clutch made etc and the end result wasn't what i wanted. I was led to believe the bmw was reliable, any problems i should know about?

I had a Range with the BMW diesel, and although it was a fine allrounder and great for cruising, I certainly can't recommend it for offroading with larger tyres. You'll constantly need to rev the engine to get going.

IMHO you'd be much better of with a TD5 or Tdi.

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I had a Range with the BMW diesel, and although it was a fine allrounder and great for cruising, I certainly can't recommend it for offroading with larger tyres. You'll constantly need to rev the engine to get going.

IMHO you'd be much better of with a TD5 or Tdi.

The 6 cylinder BMW engine has got to be better than a TDi hasn't it? It will be a in a lighter vehicle so should be reasonable IMO, just because its not great in a P38a doesn't mean it won't do the job in a lighter classic.

You have to work the 200/300 TDi's hard to get them to go. Even harder if they fitted them to the P38's.I'd be surprised if the DSE Range Rover is slower than a 200/300TDi & I think its probably heavier.

I imagine that with a larger intercooler, & a few tweaks a BMW diesel should perform quite well.

Have you considered the Isuzu 2.8 or 3.1TD's ? I have been quite impressed with them & they are dirt cheap. They perform well & return good fuel consumption. They rev much better than a TDi aswell. Easy to get a little more power out of them with a large front mount intercooler & an adjustment to the fuel screw on the pump. They are much better than a TDi in my opinion. The conversion kit is around £300 new but you can often pickup the bits used on eBay.

The Isuzu is also quite compact, much shorter than the 6 cylinder BMW engine. Its also a cross-flow engine which makes it easy to fit the pipework to a cheap intercooler infront of the radiator.

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The 6 cylinder BMW engine has got to be better than a TDi hasn't it? It will be a in a lighter vehicle so should be reasonable IMO, just because its not great in a P38a doesn't mean it won't do the job in a lighter classic.

I must admit the BMW isn't bad for cruising at high speeds (the DT will easily do 100mph), but it appears less lively on low revs than a Tdi. Which in my book makes it a poor choice for an offroader on large tyres.

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Why are you so attached to your LT? Isn't the R380 a better box, certainly in Defender form anyway?

If its to keep conversion costs down its a false economy. The best way you could tackle this conversion is get a written off P38 donor car. You're gonna need so many of the parts that provided you find the right donor it's gonna work out much cheaper to buy em all at once.

You're gonna have to make up some engine mounts anyway so throwing together a few gearbox mounts isn't gonna ruin your year...

I dont know if the R380 bellhousing differs in length depending on which engine it's bolted to but I do know that the Td5's R380 box and bellhousing can be sat on custom gearbox mounts in such as way as to use the original chassis mount holes and enable the use of standard sized LR prop shafts. And just as importantly for you - given that you need to squeeze 6 cylinders inline into the RRC bay - the set up will leave you with 100% of the useable length of the RRC bay to house the engine. You with me? What I mean is I know that once you have a Td5 and it's cooling system in a RRC engine bay it's pretty tight front to back.

Now that you've gotten me thinking about it I'd have to say do your utmost to root out whoever's done this before, photo's advice whatever - just to establish how they did it. I'd be curious as to whether they had to modify the front panel and/or bulkhead to make room. Maybe the BMW 6 is a very compact lump but either way it's a straight 6 and I know from experience a straight 5 is just comfy in the RRC.

About the BMW 6 - an uncle has a P38 D and he had JE do a performance upgrade on it, went from being massively underwhelmed by he standard car to being a very happy boy after the mods. That said apart from his shooting days he doesn't offroad and his right foot is his light foot.

I'm obviously biased but Td5 is just as tunable, will be much easier to find in donor car form, will come with an R380 with the outputs on the correct side and will overall be a much cheaper conversion. The only big money you'd possibly spend is a single piece flywheel for your offroading and possibly a GKN overdrive for your onroading...

IF you did have a P38 donor you could go the option of sticking portals on too, I'm no expert on them but wouldn't they solve your transfer case output problems!? Oh the joy of a snowballing custom build!

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Why are you so attached to your LT? Isn't the R380 a better box, certainly in Defender form anyway?

If its to keep conversion costs down its a false economy. The best way you could tackle this conversion is get a written off P38 donor car. You're gonna need so many of the parts that provided you find the right donor it's gonna work out much cheaper to buy em all at once.

You're gonna have to make up some engine mounts anyway so throwing together a few gearbox mounts isn't gonna ruin your year...

I dont know if the R380 bellhousing differs in length depending on which engine it's bolted to but I do know that the Td5's R380 box and bellhousing can be sat on custom gearbox mounts in such as way as to use the original chassis mount holes and enable the use of standard sized LR prop shafts. And just as importantly for you - given that you need to squeeze 6 cylinders inline into the RRC bay - the set up will leave you with 100% of the useable length of the RRC bay to house the engine. You with me? What I mean is I know that once you have a Td5 and it's cooling system in a RRC engine bay it's pretty tight front to back.

Now that you've gotten me thinking about it I'd have to say do your utmost to root out whoever's done this before, photo's advice whatever - just to establish how they did it. I'd be curious as to whether they had to modify the front panel and/or bulkhead to make room. Maybe the BMW 6 is a very compact lump but either way it's a straight 6 and I know from experience a straight 5 is just comfy in the RRC.

About the BMW 6 - an uncle has a P38 D and he had JE do a performance upgrade on it, went from being massively underwhelmed by he standard car to being a very happy boy after the mods. That said apart from his shooting days he doesn't offroad and his right foot is his light foot.

I'm obviously biased but Td5 is just as tunable, will be much easier to find in donor car form, will come with an R380 with the outputs on the correct side and will overall be a much cheaper conversion. The only big money you'd possibly spend is a single piece flywheel for your offroading and possibly a GKN overdrive for your onroading...

IF you did have a P38 donor you could go the option of sticking portals on too, I'm no expert on them but wouldn't they solve your transfer case output problems!? Oh the joy of a snowballing custom build!

Cheers for that post,

I had a prolonged chat to Dave ashcroft today, he seemed to think the only simpleish way around it is to get a p38 r380 and send it his way and he would rebuild the back end to fit my lt230. This however got me thinking on YET ANOTHER possibility.

If it just the rear end of the p38 r380 that would be in my way.

Why cant i get a 300tdi defender r380 box which has the long input shaft (the majority are this type right?) :blink: and the correct gearstick arrangement to replace my long stick lt77, source a P38 r380 bmw bellhousing. Put that on the front and then just connect the whole lot to my LT230, thats all relying on the only difference between the p38 and the def r380 is the back end ofcourse.

MY HEAD IS GOING TO EXPLODE!!! :blink::unsure:

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I must admit the BMW isn't bad for cruising at high speeds (the DT will easily do 100mph), but it appears less lively on low revs than a Tdi. Which in my book makes it a poor choice for an offroader on large tyres.

Yes the figures do seem to favour the TDi lower down the rev range with the maximum torque being available earlier.

2.5 DSE

MAXIMUM POWER OUTPUT: 134 bhp (100 kW) @ 4400 rpm

MAXIMUM TORQUE: 199 lb ft (270 N.m) @ 2300 rpm

200 Tdi (Couldn't find the 300's spec but its fairly close I'd imagine)

111bhp @4000rpm, 195 lb-ft @1,800 rpm

If the BMW 2.5 is happier to cruise at higher rev's you would get away with changing the transfer box to the defender 1.4 or even the 1.67 wouldn't you?

The 200 & 300 tdi's are quite flat higher up the rev range. I don't think they would be happy at 100mph.

100mph on 35" mud tyres is around 25mph over their speed rating & wouldn't be safe.

I'm not a big fan of either engine & not an expert. But in my opinion the BMW 2.5 is the better of the 2 engines, only marginally though, & I doubt it'll be worth the extra hassle in standard form.

The TDi's are simple to maintain & easy to fit. Just lacking in power in my opinion, but I prefer larger diesels & v8's.

The isuzu diesel has been the only small diesel engine I have been reasonably impressed with, I find the 200/300tdi's just are a little slow on road.

The TD5's & other modern diesels are great but expensive & complex to fit into a classic range rover.

If you can do most of the work yourself its still worth going ahead & fitting the BMW diesel. It should be nicer to drive with a BMW engine, I imagine the perkins is great off road but really slow on road, it doesn't rev very freely does it?

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Yes the figures do seem to favour the TDi lower down the rev range with the maximum torque being available earlier.

2.5 DSE

MAXIMUM POWER OUTPUT: 134 bhp (100 kW) @ 4400 rpm

MAXIMUM TORQUE: 199 lb ft (270 N.m) @ 2300 rpm

200 Tdi (Couldn't find the 300's spec but its fairly close I'd imagine)

111bhp @4000rpm, 195 lb-ft @1,800 rpm

If the BMW 2.5 is happier to cruise at higher rev's you would get away with changing the transfer box to the defender 1.4 or even the 1.67 wouldn't you?

The 200 & 300 tdi's are quite flat higher up the rev range. I don't think they would be happy at 100mph.

100mph on 35" mud tyres is around 25mph over their speed rating & wouldn't be safe.

I'm not a big fan of either engine & not an expert. But in my opinion the BMW 2.5 is the better of the 2 engines, only marginally though, & I doubt it'll be worth the extra hassle in standard form.

The TDi's are simple to maintain & easy to fit. Just lacking in power in my opinion, but I prefer larger diesels & v8's.

The isuzu diesel has been the only small diesel engine I have been reasonably impressed with, I find the 200/300tdi's just are a little slow on road.

The TD5's & other modern diesels are great but expensive & complex to fit into a classic range rover.

If you can do most of the work yourself its still worth going ahead & fitting the BMW diesel. It should be nicer to drive with a BMW engine, I imagine the perkins is great off road but really slow on road, it doesn't rev very freely does it?

I currently top out at 70, although 65 is comfortable. As soon as an incline comes along down she goes! Offroad its fairly good but i do find a few situations where the engine is too gutless until its on boost, it will rev too 3500 quite happily. I fitted Methanol injection 50/50 mix of methanol and water, which improved it greatly but only comes in after 8psi of boost. Its the Jap designed perkins. The engine never came turbocharged and so is retrofitted with a turbo, the engine is 80hp N/A. The main problem is that the fuel pump hasnt been changed so it doesnt increase the fueling when on boost, i think this is the main downfall.

A chip from twisted will increase the bmw 30hp and increase the torque by 60nm, JE also do a chip that produces similar results.

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how do

iv got a disco running a bmw motor

its the earlier motor tho , so very simple with no electrics , lots beter than the p38 . i had a deisel p38 and theres far to much elecs on it

the set up came from a rrc

im running 37" boggers , lt77 gbox and a 1.6 lt30

on the road it goes ok , thing with the bm motor it revs lots , iv seen near 6000 rpm from it ! but theres not that much low down , thing with the early motors is they had smaller turbos so the boost comes in earlier

off road u need to keep the revs up or it dies , im looking at changing to auto tho so it aint gona be a problem , or i may pull it all out a go v8 auto !!!

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I'd go for the Tdi with a bigger intercooler. Plenty of go - especially the 300 which seems to have a smoother and wider power range than the 200.

My 200 runs a Brunel Performance upgrade and I can recommend Jon's prices and advice.

Edited to add: My mate has a RRC with 35" KL71's, 200 Tdi and LT77. To counteract the tyre size he had fitted a 110 transfer box and with the Brunel I/c and his is quite sprightly. Although he won't do a hundred mph in it, especially with over a 5" lift!

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Thanks for all the replies guys,

Im going to have a long hard think about the way to go from here, still leaning towards the bmw (complete engine with loom and ecu for £100 locally gwo apparently :P ), however the simplicity of a tdi is very tempting!

Thanks again!

Paul

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I wonder how much different the BMW unit is to a VW/Volvo straight 6?

I tried a Classic with that engine once, bolted to the ZF slushbox and it was a really nice drive and felt quite powerful. The only reason I didn't buy it was because the guy wouldn't budge on price over an oil leak from the rear crank seal.

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  • 2 months later...

i had a m20 bmw turbo diesel in my disco , its the older version of the p38 motor

i still have the convertion plate to mate it to a lt77

but id not recomend it for a off road truck , it has no low down power

if u rev the s**t out of it it went realy well on the road

of road it keeps stalling and makes it hard work

it did sound the dogs tho , i had a straight through exhaust on mine

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