TR7 and LT77 quandary

[nitemare]

a mate has been given a tatty old TR7 (back of shed find) that supposedly needs not too much welding (no idea of what other work it'll need) with a dead or no engine in it and apparently it has an LT77 gearbox

now the question(s) is, was the bellhousing a special one for the TR7 to attach it to the engine or was the engine adapted to fit the gearbox ? (special backplate)

if not a special one for the TR7, what other engines were bolted to the bellhousing ?

he has a daft idea of power plant (no not V8) that is pretty commonly used in rover motors and i'm reasonably keen to help him get this sorted as he's helped me out quite a bit in the past with bits and pieces ( i feel i owe him)

he's trying to keep this project very quiet at present so i'm not at liberty to divulge the powerplant intended and i haven't even seen the car to date so no idea if it's a hardtop or ragtop, condition or anything but i'm always up for daft challenges

the only real thing i need to know at present is bellhousing stud pattern (which is why i need to know if it's specifically for the TR7) as i'm pretty certain i could build my own engine backplate/adaptor if needs be, although i "might" struggle with starter location

Cheers
Pete

[colnerov]

Hi, the bellhousing for the TR7 only fits the TR7 four pot. The V8 one is different. The one for the Sherpa Petrol 'O' series and Prima diesel engine, and the Rover 820 'M' and 'T' engines are different again. If it is a further different engine again then you will either have to make, as you say, an engine backplate. Or alternatively a plate to mate the new engines bellhousing onto the front of the LT77.

Colin

[nitemare]

Thanks Colin, i'll pass this onto him

would the sherpa and TR7 bellhousing be the same depth ?? as that might be a way around it

[colnerov]

Hi, they will be similar depth, the first motion shaft is the same length. I do have both bellhousings in two seperate locations so can measure for you but not straight away.

Colin

[nitemare]

excellent news that the first motion shaft is the same length, this potentially makes his decision on which engine to fit a little easier

the measurements would be appreciated

Thanks
Pete

[colnerov]

Hi, Pete, the bellhousing depths from engine rear face to the gearbox front face are as follows-

TR7 6 5/8" or 168mm

Prima 7" or 178mm

Colin

[vitesseefi]

Dolomite Sprint engine will fit straight on the TR7 bell.

Nick

[nitemare]

thanks for the measurements, it gives us different possibilities

i don't think he wants a dolly engine, something a little more offbeat is his thoughts

[Smiler]

I fancied building a TR7 and had plans to fit the engine and gearbox from a manual Jaguar S-Type (approx £600 from ebay for a donor car). All alloy 3.0ltr V6 with 240bhp and a 5-speed gearbox.
I ended up with a Scimitar instead but I do now have an S-type engine & box to go in it.

[MrSpeedy]

Mar 10, 2015 20:51:32 GMT vitesseefi said:

Dolomite Sprint engine will fit straight on the TR7 bell.

Nick

Are you 100% on that?

I seem to remember having to make a modification to the back plate when I had an LT77 on a Sprint enigne. Although it was in a Spitfire and a fair few years ago now

[misterbob]

Mar 11, 2015 22:21:56 GMT MrSpeedy said:

Mar 10, 2015 20:51:32 GMT vitesseefi said:

Dolomite Sprint engine will fit straight on the TR7 bell.

Nick

Are you 100% on that?

I seem to remember having to make a modification to the back plate when I had an LT77 on a Sprint enigne. Although it was in a Spitfire and a fair few years ago now

Should be a straight swap. 1850/Sprint and TR7 engine uses the same block.
I've helped put a 2.0 TR7 lump in an 1850 Dolly, so it does work.

The V8 LT77 has a different length input shaft, from memory.
Tried swapping a V8 bellhousing onto a 2.0 TR7 LT77 and it was clear, before we started, that the bellhousing depths were very different.

[MrSpeedy]

Yeah, I know they're the same block, I just seem to recall something about the clutch slave cylinder and having to grind a bit of the back plate away ?!