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i am building my 1071 project and have the chance to puchase some h4s. i have been told that if i want good low down torque and mid range performance, i should stick with the h2s, as the h4s work better on the larger engines at high revs, what do you all think?

id stick with the hs2 on a road 1071

one of mine runs h4's and it has some fairly epic carb standoff at lowdown revs, its always ruined it (well, that and the 649 cam)

my gtm is a far, far sweeter engine to drive on the road with the hs2, and its certainly quick enough, its reving to past 7 with no fueling issues

What Rich says is true if you are daft enough to use a 649 on the road.

Personally I would never opt for H2's over HS4's on a mildly tuned road going S motor.

I have run 4 or 5 1070's with H4's & a 544 cam they have never been an ounce of trouble.

Both Downton & Speedwell also used H4's on their road going conversions in the 60's so I don't reckon they can be far off the mark.

I have never been a fan of modifying carbs, as I have always believed that to choose the correct one to begin with is the important thing, rather than modifying one that is too small to flow better.

the 649 was an error, I admit that!

my gtm is such a sweet car on the hs2 though, it has won me over

bmcman.ie wrote:i am building my 1071 project and have the chance to puchase some h4s. i have been told that if i want good low down torque and mid range performance, i should stick with the h2s, as the h4s work better on the larger engines at high revs, what do you all think?

...h4,s or hs4,s have surely got to be an upgrade in producing more bhp for any cooper or s ??..most of the original tuning companies would offer bigger carbs along with better cams and other goodies...my 1330 had h4,s fitted as part of a total upgrade to engine/gear box and once the car was set up/tuned on a dyno they have never given me any grief in 7+ years.....so go for it !!! foxy52

Let's face it, many people don't use a mini everyday, so you might as well have a noisy one with a ridiculous camshaft and silly manners.

A 1071 with a 649 must be quite exciting though

Dad used a single H4 from a Jag on the 850 racer, on a home-made manifold with a home-made cam engineered by simply grinding the heel of each lobe down and winding down the tappets. 'Revved to well over 8000rpm and mum drove us to school in it on Mondays after the racing.
She was very embarrassed as she had to rev it to about 4000rpm at the lights and dump the clutch to prevent it stalling. However, we thought it was great!

P.S. 2 x HS2s would be my choice

bmcman.ie wrote:i am building my 1071 project and have the chance to puchase some h4s. i have been told that if i want good low down torque and mid range performance, i should stick with the h2s, as the h4s work better on the larger engines at high revs, what do you all think?

I've known a few people that have run cammed up 1071s on H4's only to take 'em off and refit HS2s for the exact reason you stated there Ian. However I do have a lovely set of H4's to sell.

My 1070 ran fantastic on the HS2s , I tried it on HS4s and changed back, though it was on a ported and dowelled 179 manifold and Speedwell ram pipes, SW5 and 1.5 Minispares forged rockers, pulled from 1000 to 7500, upto 40mpg, 100+MPH 86 BHP AND SUPER SMOOTH, then again 1070s are ace

rich@minispares.com wrote:the 649 was an error, I admit that!

my gtm is such a sweet car on the hs2 though, it has won me over

yes.....I can vouch for the '649 being somewhat of an 'anti-road' cam having once bought an Australian MKII S with said cam and HS6s liberated from an X6 Kimberley (not by me). It was an impossible pig and behaved so much better when rebuilt and detuned to HS2s, 12G940 and a 731.

Ove got a +40 SA 1071 with a 544 and twin Hs2..... I'm fitting a SW5....
I cannot be arsed with the 544 on the road.
I'm a getting old?? Rich, I guess you know the feeling....?
I tried this on a single Hs6. That wasn't as responsive as the twin2s.

A friend of mine has got a 1380/266 in his Marcos, on Twin Hs2s
Suuuuuper smooth. My favourite road engine.

In the shed wrote:
A 1071 with a 649 must be quite exciting though

I built it when I was far more of a hooligan than I am now and thrashed it like a rented mule when you could afford to treat mk1's like that (and in the days before speed cameras...)

I often saw 8200rpm in top gear with a 3.9 final drive

it would tick over at 1200 rpm all day long, but had nothing under about 2500 rpm, so you had to either set of like your trousers where on fire, or tickle it way like a pensioner.

im ashamed to say that I haven't even seen the car for about six years, its been sat under a cover in a garage piled high with rubbish - it would need re camming before I could be bothered with it nowadays though