Dual/Twin SUs

[ScottieJ]

I have been discussing the idea of building a Twin SU set up for the 1.3/1.6 8V engine with a guy from the US as I feel that it would net more power gains than a single HIF44 set up. It will require quite a bit of work to build an inlet manifld but I dont think it is going to be too hard to do, the main problem is that I can't TIG weld so I will be relying on a few favours from my old boss

The idea came about during a disussion on the single SU carb set up as they do not really have SU carbs available easily like we do in the UK and looking at this graph a HIF44 is more suited to 1500cc and smaller. so why not run 2 HIF38s instead?

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The hardest part to overcome will be re directing the water jackets in a stock inlet but this shouldn't be too hard to do.

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Then the idea is to either have the carbs mounted entering the inlet here

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or coming in above the water jacket like so

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[Tramp]

Looks Like a brilliant Idea, Could you do away with water in the manifold altogether, on the old minis (with hifs) did they just use twin swan necks?

Also It reminds me of an old post on Difflock where some foreign bloke had an sj with the 1.6 vit engine with twin twinchoke webbers, I thought it would be great I mean the webbers good on its on but twin.... Like a drag strip racer

[twiss]

The only thing with that is water actually cooling the engine.
I'm not so sure about on the mini but on the sj all of the coolant goes into the engine through the inlet

So you would have to have water in it still.

I suppose you could use the swan neck things like on a mini but you would still have to get water into the engine

[dan_2k_uk]

It could be alot of work for nothing though!

Both axis on the graph say aproximate so im sure there is a bit of room to move.

Also with it being a zero contact engine it will never actually be intaking the full capacity of each cylinder anyway so the ammount of air actually required is probably less than a 1500.


If you want my old 1300 manifold to cut up and have a play with you are welcome to it when you pick up your other bits.

Dan

[ScottieJ]

Yeah I know it's a lot of work, but I think it should net a few performance gains over a single hif44. that would be cool, if I could have that, It might take me more than 1 attempt to get it right was looking at a few mini forums about it and they think the hif44 is good for 100bhp but if you look at old MGs, the 1600cc+ engines run twin HS4s, they are the old version of HIF38s

I did try phoning you last weekend about popping round for those bits but I couldn't get through.

[dan_2k_uk]

I've been in deepest darkest Norfolk.

I'm back now so you can pop over whenever you fancy it.

Just gimmie a call first

Dan

[lazy rambler]

Hay, there's nothing deep and dark about norfolk, it's a great place to live, just not so good for off-roading

[Henry]

Like the thinking scott, but would it not be cheaper, easier, and more reliable to fit EFI, and chip it a few inches from explosion?

[dan_2k_uk]

I love Norfolk.

Was just refering to the phone signal.

If I wrapped myself in tin foil and did a handstand in the right spot I could get 1 bar

[ScottieJ]

Like the thinking scott, but would it not be cheaper, easier, and more reliable to fit EFI, and chip it a few inches from explosion?

Maybe, but there's less electrics to go wrong with SUs

Either way Tan Zuk liked the idea so much he's already made a start, I'm gonna source some hif38s for him and send them over to the US because he can't find any other there

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