1500cc Midget engine swap

[davidpidge]

Hello all!

I'm looking to upgrade my travellers engine soon. I was obviously looking for a 1098cc to replace the 948cc it has. I assumed this would be a 'straight swap' (ignorance is bliss!) so was scouring ebay etc. but have found a 1500cc midget engine and gearbox. Would this be a viable alternative? Obviously the plan is to not have any structural mods. I want to use the existing gearbox crossmember if possible. It's a '56 traveller with the original 948cc and smooth case box.

Other than that whats the easiest swap? I assume any swap will involve a new/modified propshaft?

[philthehill]

Can be done but not easy.
Better and easier with a 1275cc Marina or Midget engine.
All the parts for fitting the Marina or Midget available off the shelf where as you will have to manufacture and fettle if fitting the 1500cc Midget engine/gearbox.
As regards the propshaft - using your existing gearbox with the Marina / Midget engine no modified propshaft required.
You will need a special propshaft when using the Midget 1500cc engine and gearbox.
The 1500cc engine has the exhaust and carbs on the other side of the engine so new fabricated exhaust as well.
The body area around the gearbox bell housing may require structural modification and at least a new gearbox cover.

Here is a Midget 1275cc engine and gearbox all ready to drop in.
http://www.ebay.co.uk/itm/Mg-Midget-Spr ... SwyjBW5tth
Might seem expensive but you will not be far short of the cost of the above if fitting the 1500cc engine /gearbox.
Phil

[bmcecosse]

Avoid the 1500 engine - it's not very strong, and as above - a LOT of work...

[davidpidge]

Thank you for the detailed reply. I do want to make everything as easy as possible. The plan is to get it done in a weekend.
Hahaha

[bmcecosse]

Well - stick with a 1098 swap then - even a 1275 swap can become slightly complicated depending on what version of the engine you install.

[davidpidge]

Well - stick with a 1098 swap then - even a 1275 swap can become slightly complicated depending on what version of the engine you install.

I think it's highly likely i will do that. Will a 1098cc engine and box mean altering the prop?

[philthehill]

No.
The propshaft from your 948cc engine / gearbox will fit straight onto the 1098cc engine / gearbox conversion.

[davidpidge]

We'll be done by lunchtime then!

[philthehill]

Or in my case 9:27am exactly.

[trabant]

Much previous experience has shown the 1500cc triumph unit is very weak in the crankshaft area if anyone does decide to go down that route check for crankshaft end float.

[davidpidge]

Cheers for the advice everyone. I'm definitly sticking to a 1098cc upgrade but if i happen to find a 1275 on the hunt, I'll have one of them.

[Fingolfin]

The best swap is to take a 1275 from a Spridget - the engine and transmission drop right in, and the 1275 has great potential for tuning, etc. Midget owners tell me it's bulletproof. I am presently working on doing such a swap - though I hear Spridget 1275s are harder to come by in Britain than in the States.

[Mark Wilson]

Yay - welcome back Fin!

[bmcecosse]

All the 1275 Spridgets here have either been restored - or already robbed of their engines...

[philthehill]

The best swap is to take a 1275 from a Spridget - the engine and transmission drop right in, and the 1275 has great potential for tuning, etc. Midget owners tell me it's bulletproof. I am presently working on doing such a swap - though I hear Spridget 1275s are harder to come by in Britain than in the States.

I would not say that the 1275cc Midget engine is bullet proof but it is better than the 1098cc Midget engine but not up to Cooper S standards though very very early 1275cc Midget engines had EN40 crankshafts and EN24V con rods the same as the Cooper S but the high spec parts were soon discarded in favour of a lower EN spec crankshaft and EN con rods to save production costs.
If a 1275cc Midget engine is required for tuning the thick sump flange is the one to go for as the thick flange stiffens up the block considerably.
Whilst the availability of 1275cc Midget engines in the UK is constantly reducing they are still available but at a cost.
For ultimate 1275cc reliability the Marina/Ital 1275cc A Plus is the block to use (if regulations permit) with steel main bearing caps (4 bolt for the centre one), a specially made EN40 crankshaft and Cooper 'S' EN24 con rods which are definably getting rarer by the day.
Phil