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MG Midget and Sprite Technical - hif44 inlet manifold

Hi,
I have fitted a hif44 to me 1275, see hif44 float vent thread, and utilised a mini spares ally manifold.
I have cut down the top of the dashpot and piston, shortened the damper and filed down the lid of the damper. The carb clears the bonnet and the engine runs well.

But, I am not convinced it is running as well as it can. At idle the piston rattles up and down and I struggle to keep oil in the dashpot. Also, I do not think the piston can rise quite far enough.

I am therefore thinking about a manifold that is designed for the Midget - a steel one from Maniflow.
They claim it is fantastic and better than everything else on the market but they have no evidence of this.
Has anyone any experience of this manifold? Is it any better than the Mini Spares one I already have?

Thanks

Dave
Dave Brown

The Maniflow one looks a bit rough to me. I also think it could be a bit longer, probably made short because it will be to fit a Mini as well. Also a bit too expensive for me to try as an experiment!

I can't see the manifold making any difference to how it runs though, what did they do to it on the RR?



john payne

I bought a steel Maniflow because I wasn't happy with clearance for the piston at full lift using the MiniSpares one.
It's nicely made and fits well, giving easy access to the manifold studs and good clearance for the centre branch of the LCB. I've only tried it on a more-or-less standard 1275 whilst I finished my 1360/type 9 combo.
If you order one, you can choose to have a servo take-off added.

Mark

M Crossley

Mark

For my info, can you elaborate on your comment below please...

I bought a steel Maniflow because I wasn't happy with clearance for the piston at full lift using the MiniSpares one

Cheers

Mark
Mark O

Hi John,
I think it is longer than the cast ally mini manifold as it is made for the Midget which doesn't have the bulkhead proximity issue that the Mini has.
It will position the carb a little further away from the exhaust manifold which can't be a bad thing, I suppose.

I have attached the picture of the mini manifold from the Maniflow website. I don't know if both pictures are of the same manifold though!



Dave Brown

I fitted the maniflow one and have found a big improvement over the cast metro manifold that came with the carb - I had to cut an angle in the metro manifold to head mounting face to lower the carb and I'm not convinced I had an airtight seal which may have accounted for it's poor performance.
Suffice to say I'm very happy with the maniflow.
one thing to be aware of is that once you've fitted the carb and a K&N filter it's very close to the inner wing. A longer manifold would necessitate cutting the wing.

Graeme
graeme jackson

Does the Maniflow drop the SU far enough to avoid dented bonnet syndrome?

THere have been loads of threads about this issue. Other factors like luck and engine mounts seem to come into it. I though that without mods, only one of the Titan manifolds did the job.
Graeme Williams

Mark O,

I milled down a Metro manifold at an angle, but there wasn't a lot of metal left by the time I'd got bonnet clearance and tidied up the matching faces where the manifold nuts fitted.

I trialled the MiniSpares one, which wasn't just a bolt on. Definite interference with the bonnet.
I tried with a flat-topped cap, LZX 1389(?). Still touched the bonnet. Fitted old engine mounts. Not enough.

I considered shortening the dashpot top, which would require cutting down the damper rod and the steel tube of the piston to allow for full lift. I wasn't happy that I could do that properly or that there wouldn't be other knock-on effects.

So I bought the Maniflow. (£170)I'd looked for a Titan manifold, but couldn't find a cheap one. (£110) Maniflow is well regarded by Vizard. It also matches my new Maniflow LCB.
People with more ability and patience can solve stuff like this. I tend to choose the easy option.
The car is sulking in the workshop at the moment. I've only just fixed the clutch concentric after fitting the five speed. And I haven't tried firing up my new engine yet...

Too many projects, not enough patience or skill.

Mark

M Crossley

My HIF44 is fitted with an Osselli manifold that has the appropriate angle to get the dashpot below the bonnet. Works well. Second hand from Ebay but not as cheap as I would have liked :(
(just so you know there's another option Dave if you can find one)
Glynn (1275RWA) Williams

Graeme J, any chance of a pic of the manifold on the car and how close to the wing it is? I've not got an inner wing so no probs there!

I've always used the MG Metro manifold and after attacking it with a file I've got about 3/8 inch clearance from the standard dash pot cap to bonnet. I'm always on the look out for a bit more power and have considered the Maniflow but as I said before it's an expensive experiment!

If I were to go for the Maniflow I'd probably try it with this filter as I think the K&N is a bit restrictive:

http://www.med-engineering.co.uk/catalogue/ancillaries/ram-air-kits/med-hif-44-stub-stack-system

It's either that or double the money for a Weber, but I'm quite attached to the SU and like the way it gives loads of power but is still easy to live with.

Like Mark I've got too many projects!

john payne

I'd love to see a side on picture of the maniflow manifold to see the relative position of the head and manifold sides.

I still maintain that one of the key benefits of the titan motorsports manifold compared to others is not primarily the magic angle but that the carb is simply mounted lower in relation to the head than many.
Dean Smith ('73 RWA)

I tried one of the MED filters. Its a while ago, so don't take this as gospel.
The Dzus fastener points upward as standard, so bonnet clearance was a problem. I tried re-drilling the backplate and stub stack. That inverted the filter, but the s/stack needed another flat because its not central in the filter case.
At present I'm using a Ramair, one edge of which presses against the inner wing.

The pic isn't very clear. The manifold enters the head pretty much horizontally. The internal finish is smooth and aligns well with the gasket and ported head. I'm using the standard 1/2" insulation spacer and a 1/8" ish stainless cable location plate that doubles as a heat shield for the float bowl.

M Crossley

Another view

M Crossley

From the third pic you can see that the manifold is basically a tube bent in a 'U'. The angle of the carb is dictated by the position of the carb mounting flange.

I like the good access to the manifold studs and the fact that the flange thickness matches that of the Maniflow LCB.
The Maniflow chaps are really helpful. They put lambda ports in two of the LCB branches, which I have subsequently had ceramic coated.
Its future-proofed for the injection system I intend fitting (See previous comment re too many projects too little skill)

M Crossley

Dean,
this is mine on a Titan manifold. - the correct Spridget one, not their more common mini version. Photo angle isn't quite right to do a proper comparison but I think you can see that the carb sits flatter than on the Maniflow version. No problem at all with bonnet contact and I didn't need to cut down the carb damper top either.
The large filter is a K & N twin SU one with a lowered replacement back plate to suit the HIF

Guy W

Mark

Many thanks - now understood. Little consolation perhaps, but mine sits a little like Guy's with no issues re bonnet or wing. Ebay purchase.....Lord knows what make, but I feel that as I also have a type 9 box fitted, the engine mounts may well be a little lower - which obviously helps matters.

Worth perservering with for the improvement of the HIF 44 over standard I feel.

Mark
Mark O

Guy

Thanks for the pics. It has always been my hypothesis that the angle is NOT the main thing to focus on. - It is the relative height of the carb mounting to the head.

My Titan was advertised as a mini manifold (back in 2006) and works just fine on the Midget.

I had another manifold with the identical mounting angle that didn't because it sat the carb higher.

I would appear from those pics that the Maniflow is the same - it sits the carb low in relation to the head rather than simply at a magic angle.

In the 10 (?) years the titan manifold has been discussed I dont think anyone has managed to picture a "mini" version and "Midget" version next to each other to show any difference.

In fact I'm not sure I recall anyone having any Titan that wouldn't fit under the bonnet - but that is only my recollection.

Dean
Dean Smith ('73 RWA)

I am still trying to get Maniflow to send me details of the tests David Vizard did on their manifolds.
Aparently, they were in the first edition of his book.
I don't know which book - tuning a series engines or how to modify you mini.
When they come up with the data, I will post it. Don't hold your breath.
Dave
Dave Brown

I'd be interested to see those results as well! I think Vizard was fairly happy with the flow characteristics of the MG Metro one, or am I thinking of Des Hamill?
john payne

This thread was discussed between 14/01/2015 and 21/01/2015

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