Morris Minor Owners Club

We have just renewed the insurance on our 1098 for the bargain price of £630! (19 year old son is primary driver).

we also asked them about going to a 1098 midget spec (twin carbs, better exhaust and around 10hp), apparently this won't cost any extra.

So time to get cracking, We have the twin carbs which will be re-built, (I know a single HIF is easier to set up but we have them and I have never had any problem setting up twin su's in the past) but the real question is around exhaust we have looked at A Maniflow LCB system which seems good value, any experience of this and what other alternatives are there?

LCB systems are great, although I think the 3-1 options maintain a little more torque higher up for some reason or another.
When Marina cast iron manifolds were easier to get hold of using those was a popular option to get a larger bore 3-1 setup, with a specific downpipe (link).

Changing one thing at a time will give you a feel for the effects - perhaps start by hacking the inlet part of the original manifold off and try it standard first?

I'd recommend the Maniflow system. I fitted one to my Midget-engined Traveller, and it fitted very easily and makes a pleasant note.

I suspect to get the extra 10bhp, you'll also need to fit the 12G295 cylinder head, or re-work your existing head.

You can have this twin outlet Marina manifold if you want

Unless you are increasing the valve overlap i.e. fitting a sports camshaft there is little to be gained by fitting a LCB exhaust manifold.
The later Marina inlet/exhaust single outlet manifold with the inlet side of it removed so that you are left with using the exhaust side is a good way to go. Vizard in his book on tuning the 'A' Series gives it good reviews.

Thanks for the kind offer but I suspect by the time I have had a downpipe made It will cost more than the LCB manifold.

On the chart shown above is there something wrong? power is the product of torque and engine speed but the higher torque line does not correspond to the higher power line?

It has standard sized valves re-worked ports (pretty much in line with Vizards's suggestions for small bore engines), a 9:1 CR and piper 255 cam it's a road car so we are really interested in optimising the low and mid range torque, the improvements there look impressive for the LCB.
It's got a mappable ignition system that is something else we could play with, might even be worth taking it to a rolling road afterwards.

On a bored out 948 (now 1030cc) I've found the Maniflow small bore system including LCB far better than the Marina manifold and free flow exhaust I had previously. This is with a mild cam which is actually more increased lift than longer duration. The Difference between the 2 systems was very noticeable, given that I had also read that, as per Phil's comment, there is little to be gained from an LCB unless using a 'long' cam.

I can't recommend a rolling road session highly enough, to ensure you're getting the most out of the mods you end up choosing

More lift which means more flow capacity can give similar results to a larger overlap of valve timing so a LCB can be of benefit.
The overall combination i.e. head, camshaft and carb(s) will determine what exhaust manifold is required.

What I'm gathering is it may not give a big improvement but it's unlikely to make anything worse, on that basis we plan to go for the maniflow small bore LCB one and a matching 2 box exhaust.

If we manage to release a mighty 10hp more (ie similar to 1098 midget) I Might have to think about doing something about the ropey gearbox and bouncy rear suspension as well (first plan is to replace the damper oil with something thicker and not 50 odd years old) I was thinking of the heavy version of this

https://www.afbmotorcycles.co.uk/motorc ... o-fork-oil.

I used something similar in my traveller, made a big difference to the ride. The car felt more sure footed and a lot less bouncy.

A straight 30SAE is more than adequate to refill the dampers fitted to a Minor. Available from most garden machinery centres or 'e' bay.
No need for fancy oils.
https://www.ebay.co.uk/itm/370567523163 ... SwIcxgCu4V
Non detergent oil is best for this application.