BMW ENGINE EXPERT NEEDED

[derangedrover]

I am trying to find out if the auto bell-housing from a Range Rover P38 2.5 diesel BMW-M51D25, will fit onto a BMW M52TUB28 petrol engine...??

I am building a Triumph Herald project and bought a BMW E46 328ci auto for a donor car, the problem is the ZF5HP19 autobox is fully electronic, so I want to use an older ZF4HP22 mechanical box, someone told me they think the P38 diesel bell-housing should fit but they can't say 100%.

Any help will be gratefully accepted

[ChasR]

They may fit, but the box bolt pattern may differ between the two.

For a few 'boxes these days, you can buy controllers.

For the engine pattern Q, I'll ask a friend. But he's fairly unfamiliar with M51s, but you never know.

Is converting the Herald 'box via an adaptor plate to the M52 unit not an option?

[nickwheeler]

Aug 30, 2020 6:51:13 GMT ChasR said:

They may fit, but the box bolt pattern may differ between the two.

For a few 'boxes these days, you can buy controllers.

For the engine pattern Q, I'll ask a friend. But he's fairly unfamiliar with M51s, but you never know.

Is converting the Herald 'box via an adaptor plate to the M52 unit not an option?

A Triumph Herald box behind an M52? One that was meant for  950cc and about 40bhp? 

[vitesseefi]

A Herald engine (61bhp max) is more than capable of destroying a Herald gearbox. An M52 will reduce it to shrapnel very rapidly.....

BMW engines come with decent gearboxes attached and interchangeability within the BMW family is good.

Herald chassis is very narrow in the gearbox area..... any auto box will be a challenge.

Nick

[legend]

have you tried the BMW engine landrover facebook group? they seem great at wiring up the engines and use all sorts of gearbox combos

www.facebook.com/groups/1106830676068639/about

[welshpug]

I've got a dead 5HP18 off an M51 knocking about if you want any pictures, I'm sure they sit at a different angle to the later engines I think, certainly the diesel variants lean over more than the M51.

[biturbo228]

Like Nick I'd be wondering how well an auto box would fit in a Herald chassis. It really does narrow very quickly past the bellhousing. It might well fit, I don't know quite how big a ZF5HP22 is, but be prepared for quite a lot of clearancing and reinforcing. Anything can fit with enough clearancing

You can see here how much choppng I had to do to my Spit's chassis to fit the saloon overdrive gearbox the second time round (out of 3):



The first time round I had the gearbox sitting higher than the top face of the chassis which caused it to foul on the seats. The third time I'd shifted the engine backwards 3" which is what you might need to do to fit the bigger engine (although the space requirements in a Spitfre are tougher than a Herald). Don't have good pics of the setup, but this pic shows some of the space requirements:



An interesting option could be the 5-speed manual from an E36 325i (and maybe 328i, not sure). They're very short, and might just fit before the chassis starts narrowing. They have a bit of a reputation for fragility amongs BMW folk, but I think that comes from people putting them behind M62B44 and turbo setups, rather than hotted NA efforts.

[vitesseefi]

The 4HP22 in my A8 was flippin monstrous, though obviously some 4wd gubbins on that too.

There have been a very few auto Heralds/Vitesse conversions which I think all use the relatively compact BW65 but even then fairly extensive chassis mods are needed.

Nick

[welshpug]

A8 would be quite different to a rwd box, as it has a diff in it.

[kevins]

This the 4hp22 in my range rover before the transfer box was fitted.





For an auto they have a narrow tapering sump, with some cutting you may well get it between a heralds chassis, rails the box above is quite a lump though, it's certainly going to need something larger than the usual Herald cardboard trans cover!

The 2wd tail housing will be more compact.


They used the 4hp22 on a lot of BMW's will none of these fit?

[biturbo228]

If you've got any measurements of the 'box I can do a quick look on my chassis and see if it might fit...

[ChasR]

Aug 30, 2020 8:20:25 GMT vitesseefi said:

A Herald engine (61bhp max) is more than capable of destroying a Herald gearbox. An M52 will reduce it to shrapnel very rapidly.....

BMW engines come with decent gearboxes attached and interchangeability within the BMW family is good.

Herald chassis is very narrow in the gearbox area..... any auto box will be a challenge.

Nick

Ah, my bad. I thought all single-rail boxes were the same, which were also fitted to the 1850 Dolomites etc.

The 4HP22 was also fitted to loads of Jags and BMWs of the 80s. As a result, it's popular gearbox for conversions. It fitted in fine into my Stag (that was from an E30). A Herald may be more of a challenge as stated.