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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Manifold for 1 3/4 SU ???

Anyone know where I can get an inlet manifold to put a 1 3/4 SU onto a 1275 ???

The mini places have mini ones but I believe the bonnet wont close because of the 30 degree up-sweep. Titan have stopped making the shallower angle (20 degree ?) ones and their last batch was sold to mini-spares who have sold out long ago.

Anyone know where I can get one from or anyone have a used one for sale??

UK preferably.

David Banks

There was a thread or two on this subject last year... and i even believe somebody on here had them made again?
David, might be usefull to check the archive on this.
Arie de Best

yepp I sure do...it even comes with 2 carter carbs...which carter was a good race name back in the day,,,just under holley

Hmmmm...well I thought it was 3/4 inch...you might have to drop a dime and ask

Prop

ebay # 250574720122
Prop

You might try emailing David at Maniflow maniflow@lineone.net if you like the looks of the one below. I am looking into one of these myself. FWIW the vacuum taps are NOT stock, but were added by Maniflow at customer request.
David "I can't just let this carb sit here..." Lieb


David Lieb

MG Metro (ally)

A
Anthony Cutler

nice find david....Hmmm, Im not sure but I think that vac port looks orginal...could be a monday morning factory job...LOL.

I am curious...how does the bias work on that type of manifold, do you have to mod the shape of the intake ports on the head? to me it looks like you will have alot of excess fuel on the outside of the curveture (inside the pipe) resulting in some flat spots thur the rpm range.

Prop
Prop

David -

A cheaper option is to find a manifold on eBay bearing the figure 4001 and the term 'hi-flow'. This is the alloy Mangoletsi 4001 (said to be still avalable new in the States from Pierce Manifolds) which has the 20-degree Spridget angle.

Tom
Tom Coulthard

Anthony Cutler...

Do you mean that an ally Metro one will do the job??? (and still be able to close the bonnet???

PS - many thanks to everyone for all the suggestions ....
David Banks

The Pierce website shows a list of Mangoletsi manifolds, including the MM-4001, described as "A type 10 degree". A call to their tech line revealed that they are made in the UK, that Pierce have none in stock, that the last one they sold was in 2004 and cost U$119, and that they will email Mangoletsi Manifolds and ask for a current price.
David "no ally Metro manifolds in this country, either" Lieb
David Lieb

David

My MG Metro manifold and HS6 fitted under the bonnet OK with a little fettling of both...

A
Anthony Cutler

Our one with a Metro manifold cleared the bonnet, but not by enough to avoid contact with a bit of engine rock. The result was a pimple on the bonnet, which grew somewhat after a keenly contested event in a field! Solution was to cut a wedge out of the manifold to change the angle and weld it back up again. Worked a treat and easy to do if you have alloy welding access.

We are doing the same with a new Mini manifold, fitting it tomorrow - will take some pics.
Paul Walbran

David. It was me last year who tried to get a batch of Titan manifolds made by Titan, but it proved prohibitively expensive for most people and we had a drop off of about 50 per cent so I abandoned the idea.
That still left me with the same problem you have.

I managed to pick up a "Minisport" manifold (which is not as steep as a Metro one but not as shallow as the Titan midget one)up at a car show autojumble for £10 and took it to my local engine machine shop and they took off a champfer at the manifold/head interface of zero at the top to 2mm at the bottom which gave the manifold enough "lean back" to clear the bonnet. I also took a little material out of the plastic dash pot top to give me a bit more clearance. It works really wel with an HIF44 carb.
Hope this helps.

Bernie.
b higginson

Thanks guys for all the help and advice - it looks like its going to have to be a Metro one that is 'adjusted'. Anyone got one they would like to sell???
David Banks

<<it looks like its going to have to be a Metro one that is 'adjusted'>>

Why, when it's not an especially good manifold - for our purposes - in the first place? The Mangoletsi is quite often on eBay, though never advertised as such, and often the 'hi-flow' isn't very legible, either. However, the '4001' is usually quite plain: just don't mistake it for the 400, which was meant for 998s and has narrow ports.

I believe the 4001's a bolt-on fit, and looks impressively designed. Of course the David Dorrington sculpture in David Lieb's pic above is probably the best of all, and a true bargain: cheaper than anything by that Giacometti chap, and much less spindly.

Tom
Tom Coulthard

This has bugged me for some time but has anybody ever had a go at shortening the dash pots?
This would also help people who try and fit twin inch and a half SU,s . And am i mistaken or does the TR7 have shortened dash pots?.
R Mcknight

I've seen the dash pots shortened, but it reduces the amount of thread for the tops to screw in so you have to be careful how much you take off.

Bernie.
b higginson

I shortened mine a couple of threads with no problems...

A
Anthony Cutler

Just to let you know that the correct manifolds in terms of angle of up-sweep etc are readily available from

Maniflow - 01722 335378 - £120 + VAT

and

Peter May - petermaymotorsport@hotmail.co.uk - £138 + VAT

It is my intention to do back to back rolling road tests with a 'Vizarded' HIF44 v. a Weber 45 and I will post the results - sometime early summer.

Thanks for all your help.
David Banks

I don't really see that it's the ideal function of an enthusiast BBS simply to steer people towards the specialist suppliers, much as one may respect them. Surely peoples' cheque books can do that for them? (I have similar reservations about tuning books aimed at the enthusiast - sorry, but I do.)

With a little knowledge (such as supplied on this BBS re Fiesta hydraulic clutch actuators, for instance), budget-conscious Spridgeteers can achieve the desired results at a fraction of the cost. This eBay ad for the Mangoletsi 4001 is entirely typical:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=180468406280&ssPageName=STRK:MEWAX:IT

(eBay Item: 180468406280, expires tonight just before 7pm, currently bid to £5.70. No personal connection, of course.)

Or am I just some lone, old socialistical voice crying in the wilderness??

Tom


Tom Coulthard

Classic Cars of Kent modify MGB manifolds for anyone wanting to fit twins to their spridget to maintain underbonnet looks.
Alan Anstead

No Tom your not alone, i would much rather sort out a problem myself and save money then get a pro to do it. I am thinking of doing a big brake conversion with princess calipers and allegro discs, yes i could buy a brake conversion off the shelf but prefer to source, machine and fit parts myself. Much more fun .
Roy
R Mcknight

Sorry if I have offended anyone.

The only reason I posted those contact details was to help anyone who was having the same problems that I was having in locating a decent manifold.

Wherever possible I do try to sort out problems myself - but I cant make a manifold and if I take the time it would take me to adjust a metro manifold etc (and end up with an inferior result) and used that time for working then I can earn a lot more in that time than the manifold cost. This also helps make sure that the Peter Burgesses and Maniflows ie small businesses are still around when we need them.

Again my apologies for any offence - I will think long and hard before posting again....



David Banks

wrong response David

this is a forum

many opinions make light work

all are right

some of the time

except MINE of course

:)

I do everything cheap

if I can
bill sdgpm

I think both sides are right. There are spridgeteers with two left hands and those who can turn scrap into performance parts. Both kind welcome tips and readily available information, if only to benchmark their own findings.
I just luv the BBS.
Alex G Matla

David -

<<I cant make a manifold>> I wasn't suggesting you made a manifold, I took the trouble to tell you about a highly effective manifold you could have bought for £16 on eBay, when your original post asked where there was 'a used one for sale'. You chose to ignore my suggestion in your posts (as you do again above, oddly) which is entirely your prerogative, but you can't be surprised by a small squawk in response - nobody likes being ignored.

I am a keen and energetic supporter of (good) Spridget businesses, albeit more through words than £££s. But I do get uncomfortable when information about fitting parts from other cars becomes a 'trade secret' not to be divulged to non-members of the Magic Circle.

Anyway I'm sorry if I offended you - and you do sound offended. However, I think these boards (like most of their ilk, I believe) require a certain robustness of approach ...

Alan -

Isn't it odd that the MGB log manifold seems to be regarded highly by tuners, where the A-series one is so reviled (mainly by Mr V., of course)?

Tom
Tom Coulthard

Tom
I dont think the MGB manifold was revered for its design it is just that it can be cut and tig welded to compact it sideways and it has enough meat on its lugs to allow for machining to bring the angle down. I, and another member, had to go that route to fit 1.5in S.U.s on his Frogeye and my Sebring rep.
I know of one Frogeye with a 1.75in HIF where the owner has used a stock manifold but then made an extension piece to go between it and the carb that lowers the angle. He, however, does have access to machinery whereas I do not.
Alan
Alan Anstead

hmmm

anyway

dashpot shortening- all well and good but you must check that by shortening it you retain enough "lift" for the piston damper rod

Geoff will tell you about doing that

requires a small adjustment (SNIP) to the steel rod that pushes into the plastic cap (It pulls out and has a turned ball end, which could be replicated with a file to let it clip back in)

It'ld be a bugger if you lost a great chunk of airflow by fitting the HIF/HS6 without checking

And "secrets"? No I'm not keen, I prefer disseminating info far and wide

Always have
bill sdgpm


I have the Titan 1 3/4 manifold, bought from APT. It's the same as Lieb's EXCEPT it has a steel pipe cast in with it to allow water heating (plumbed into the heater supply line). Mine leaked water (and rust) into the rear intake runner. I was not able to find the leak so eventually blocked off the water supply and sealed both ends of the pipe. I asked APT to replace it but they told me Titan had quit making them. Maybe the leaking was why? I always thought the choice of materials was a little questionable since steel and aluminum have different expansion rates. Other than that, I like the ease of dealing with just one SU and I have just as much or more power as I had with the original 2 carb setup.
JM Morris

Well, I was very pleased to see your posting Tom as I bought just that same bit of Mangoletsi 4001 kit off e bay last year as the angles looked about right. Time and lack of garage space has prevented me actually doing anything with it but as you reckon it will bolt on with no bonnet issues I am resolved to get on with it soon! I do like my twin SUs but I'm never entirely convinced I've got them in tune or balanced, but I'll keep them set up as they are and if the single carb conversion doesn't work out I can bolt them back on and flog the hif 44 and manifold back on ebay and might even make a profit!
Matt 1275 Bucks

Tom,
I agree with you in principle. Bear in mind that such auctions generally are not interested in the hassles of selling overseas (who can blame them?), so those of us stuck on the wrong side of the pond get a trifle annoyed at hearing about Princess calipers, Metro intakes, Riley brake drums, etc., most of which are unobtanium to us.

I intend to try an HIF6 one of these years, but I am not so interested as to spend that much money on it when there are other issues needing resolved a bit more promptly.
David "what tuner book?" Lieb
David Lieb

And yes, most online gatherings like this require that you
1. Assume everyone is your friend and simply has trouble expressing it.
2. Put on another layer of thick skin every day.
3. Realize they don't mean it that way.
4. Don't let the prescription lapse on those rose-coloured spectacles.
David "equal opportunity offender" Lieb
David Lieb

David,
I'm sure there's enough of us on here who would trust you enough to bid on, buy and ship old BMC scrap (provided its small and relatively light!) off ebay on your behalf in return for the promise of an envelope with a few dollars in it.
A whole new engine for Prop might be another matter though.....
Matt 1275 Bucks

Just musing here...
What about using a stromburg rather than an SU on the mini manifolds. They are a lot lower...
Tim
T Dafforn

Matt,
Thanks for the offer. Might take you up on that one of these days ;-)

Meanwhile, I found one of Tom C's Metro manifolds at a reasonable price (to me, anyway) from a vendor willing to ship it to me without gouging.

Now about some of the other bits...
I imagine I can build some kind of a heat shield for it.
Hmm, air filter?
Carb spacer?
Our local British car swap meet is Sunday, so it would help to know which marques might be useful ;-)
David "maybe Harley?" Lieb
David Lieb

<<It is my intention to do back to back rolling road tests with a 'Vizarded' HIF44 v. a Weber 45>>

David,

Will be very interested to see the results. We did the same at one of the 'Power Shoot Outs' a while ago with our 1380 and the difference was +4bhp to the Weber - 102bhp -> 106bhp. The SU is mildly 'Vizarded', but also had a Metro air box with K & N filter. The Weber had short ram pipes inside a quite large K & N filter.

For the next shoot out I only used the HIF6 and got 104 with the CR up to 10.4, and just as a quick experiment took the whole air box off and got 112bhp, which means that the air box was robbing the SU of 8bhp!!

I have since fitted a stub stack and round K & N filter to the SU, but no RR results yet.

Not sure that we found any conclusive difference? But I wonder whether the Weber would come more into its own with a more adventurous cam - ours is a 276. Oh and coming back 'on topic' it has a Titan inlet manifold - but then there is plenty of room under the bonnet of a Minor!! Sorry about that.

Richard
Richard Wale

Richard -

The Titan actually has quite narrow runners (29-30mm at the ports): with a 276 and 1380cc, could you not do with shifting a bit more air at high revs? If so, you too could use a Mangoletsi 4001 (port size 33-34mm) or the lovely Maniflow steel, which is probably 34mm all through.

Thanks for posting your dyno comparisons – real-world figures are always fascinating. Was the Metro airbox the 90 degree elbow device? Rather than another HIF/Weber shoot-out, how about a HIF/Weber/Mikuni HSR45 showdown? Now that might make for some cat/pigeon interpositional interest.

David (Lieb) –

I will try to come up with some HIF-equipped BL models, but they didn’t sell many in the US, did they? Something to do with the American public having finally lost patience, I believe ...

Actually I can’t be 300% certain about HIF clearance because I don’t have a steel bonnet on any of my cars – don’t hold with the things. (If God had intended Spridgets to keep their steel bonnets, He wouldn’t have brought John Sprinzel among us ...)

However, I have done a Giant Test of manifolds and measured – principally – the height of the top of the standard piston damper’s plastic ‘top hat’ relative to the underside of the cylinder head. The other two figures are horizontal distances: the highest point from the manifold face of the head and the furthest projection (the fuel float bowl) from the manifold face:

Titan Spridget (20% angle): 207 / 145 / 227

Mangoletsi 4001 (10% angle): 207 / 156 / 215

Minex: 214 / 141 / 211

BL MG Metro: 216 / 126 / 206

Howley: 218 / 119 / 221

Janspeed: 226 / 108 / 238

Mangoletsi 400 (small ports for 998): 232 / 127 / 249


Sadly these measurements are not ideally accurate, as I lack the equipment for 3D. Assume an error of at least 1-2mm, but hopefully they’re generally indicative. For comparison purposes, a single Metro phenolic spacer with gaskets each side was fitted between carb (an HIF44 from a MG Metro) and manifolds, without a heatshield, and a well-flattened secondhand manifold/head gasket was used.

Both the Minex and Metro items are markedly swan-necked, and the Minex looks very similar to the period Maniflow alloy manifold, unmarked clones of which are all over eBay. The Metro is certainly the shortest - huddling over the centre exhaust outlet like a BL striker over a picket line brazier. The Howley, Janspeed and both Mangoletsis rise up at more uniform angles. The Titan is more or less level.

You could gain a few extra mm clearance by losing the spacer (with a possible small loss of airflow around the butterfly), and quite a few mm more by substituting the flat-topped piston damper mentioned in the archives (LZX 1389 – though having tried it 6 years ago, I complained of ‘engine pick-up’ being ‘rougher’ – whatever that means).
Alan –

I think I was remembering Peter Burgess’s comment: “The factory inlet manifold for the SU is an excellent piece of equipment which can be used through all states of engine tune.” It may be that the MGB port runners are big enough to get over the stickier laminar flow problems of the A-series log manifold, but this is nevertheless shocking to read for the likes of us brought up on David Vizard’s swingeing indictments.

You can’t help feeling there was some special pleading going on to reinforce Mr V’s approach that the inlet side was all-important, when traditionally tuners knew that sorting the exhaust out was the major priority. (His tests for manifolds are almost wholly based on outright airflow, when the biggest constriction in the inlet tract occurs at the valve.) However I will not join with those who reckon it was all because Mr V had shares in K&N!

Peter Burgess’s comment above is from his book in Veloce Publishing’s Speedpro Series How To Power Tune MGB 4-Cylinder Engines For Road & Track, which should be on every Spridgeteer’s shelf. It is well-written, clear and hugely informative (and so much better than the A-series one by D*s H*m*ll). And yes, the A-series really is just a smaller version of the B-series, that’s how it was designed, though of course there are occasional subtle differences.

Tim –

I don’t think there is much wrong with the Stromberg CD – it just suffers from having been Tr*umph’s way of getting round the SU patents, when BMC started charging over the odds for SUs. Its rubber diaphragm can perish (Tesco’s 99 might be a no-no?) and the needles wear, as they do on SUs. Mind you, the Tr*umph connection alone is enough to get many people shunning them. How marqueist!

Tom
Tom Coulthard

Is it OK to use a ZS off an MGB? or move up with one from a Lotus? or get reliable with a Volvo one? or get luxurious with a Jaguar one?
How silly.
I love SU, and I was a dealer mechanic for TR and Volvo, so I've seen all the problems of ZS, including when TR told us to throw away the ZS complete with manifolds on early TR4 to fit the warranty replacement SU system, but:
I think it's a true neglected treasure, and at least over here, you trip over them everywhere. HIF6/44 are nowhere on this side.
Concentric float bowls too.
Not a bad idea to eliminate the thermo idle screwer-upper on the side of early ones though!
And the right early ones have adjustable but fixed center needles, or you can easily make adapter bushes to take them or SU needles, so that gets better.
The diaphragm vs the precision matched vac chamber at least means ham fisted amateurs don't do permanent damage.

FRM
Fletcher R Millmore

As expected, no spacers or air filters for 1.75" SU carbs at the swap meet today, although there were a few 1.75" SU carbs.

I did pick up a few odds and sods I didn't really need, including three Johnny Lightning Bugeye models (yellow, blue and leaf green), and a cunning little in-line ammeter by Hoyt (see photo).
David "currently still looking" Lieb


David Lieb

David -
Seriously jealous about that way cool & useful meter!

FRM
Fletcher R Millmore

David (Lieb) -

Drop me an email with a postal address and I will send you a spacer.

Tom
Tom Coulthard

Air filter wise I used a K&N 56-9135 for my HIF44.
Dean Smith ('73 RWA)

Tom,
Congratulations! You have managed to get the spacer to arrive on my birthday! Now I will have to get this manifold and carb onto my Midget. Thanks so much!
David "I am running out of excuses" Lieb
David Lieb

This thread was discussed between 04/02/2010 and 25/03/2010

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.