HS4 abutment plate

[MorrisJohn]

I need an abutment plate as I’m changing my carburettor to an HS4 (to match the Marina 1275 engine).

Would a plate for an HS4 carb from a mini be suitable, or would the throttle and choke cables be on the wrong side?

[panky]

I have a Mini HS4 and abutment plate on my traveller. The throttle and choke cables are to the front of the engine, not sure if this is the same as a Marina

[MorrisJohn]

Thanks panky. My cables would be to the rear of the engine bay.

I had an interesting chat with a Minor specialist today, who implored me to leave the current set up alone. Currently I have Marina 1275 engine, HS2 carb, 1098 manifold, air filter and exhaust. I was told it should “pull like a train” on that set up and if I change to HS4 all I’ll do is ruin fuel economy.

The dizzy I haven’t actually checked, but I’m told it needs changed depending on which carb I’m running and that over-advancing is a particular problem on 1275 upgraded cars. It was suggested a slightly modified 45D is the best option.

I had been considering changing to a standard Marina 1275 manifold (which I was told today I’d also need to inlet water heat) corresponding exhaust, HS4 carb and K&N air filter. And after all that getting an SU tuning whizz to set it up. I thought keeping it all Marina made the most sense and would let the engine perform as intended. I was very much put off today though.

Very much back to the drawing board now. Not sure what to do??? I have most of the bits already (manifold, K&N & refurb HS4 carb), but I’m now thinking it might be a better idea just to have the SU guy tweak the current set up? Sell the current parts, or plough on…?

[panky]

Sticking with the HS2 will not allow the engine to run to it's potential, in my opinion you need an 1 1/2" carb at least (HS4 or HIF 38) and a similar sized bore exhaust system. The point of fitting a 1275 is to increase the available engine power and to restrict it so seems a bit of a shame.
If you do decide to carry out the modifications I would ditch the K&N cone filter and fit a slightly modified (inlet tract cut off and a few holes drilled in the casing) Mini air box with a K&N element inside - the cone filter can be quite noisy and there's little benefit over the air box set up.

[MorrisJohn]

Sticking with the HS2 will not allow the engine to run to it's potential, in my opinion you need an 1 1/2" carb at least (HS4 or HIF 38) and a similar sized bore exhaust system. The point of fitting a 1275 is to increase the available engine power and to restrict it so seems a bit of a shame.

Yeah, that was the type of thinking going on in my head. Air filter wise I fancy the K&N cone filter for nostalgic reasons. I had one fitted on my 1275 mini (my first car). The air sucking noise doesn’t bother me, in fact I quite like it.

What I have assembled parts wise is: refurb Marina 1275 manifold (with vacuum take off for brake servo), refurb HS4 carb (from a Marina) and K&N cone filter. I have a friend that’s offered me a suitable good used exhaust, taken from one of his cars.

I was going to fit all the above (hadn’t planned water heating the manifold) and then get an SU tuning guy from the mini scene to profile a needle, set up the mixture etc. I hadn’t planned on changing on the dizzy, but now it seems that’s something I may need to do?

I’m interested to know if these plans are a sensible way forward? I just want a little more top end poke.

[panky]

You can fit a water heated manifold (and they can be picked up pretty cheap) without connecting the water up but it's a simple job to re-rout the heater pipes to fit.
I'm a Mini man too and run a '91 Cooper. I grew a bit tired of the induction roar (getting old ) and re-fitted the original set up with the 'Cooper' embossed inlet tract. Goes just as well but a bit more sane.

This is the set up I have at the moment. !2G940 head on a 1098, HS4, alloy inlet manifold, Midget exhaust manifold into 1 1/2" system. But what you are planning sounds pretty good