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MG Midget and Sprite Technical - Grinding carbs and inlet manifold

Good afternoon,

As the temperature decrease, I am looking for some jobs which I can do from my living room, instead of in front of the car (1275cc from 1972, twin SU carbs) :)

I was looking at manifold, and found some reading in the archives about how to improve the flow through the carbs and inlet manifold.

https://tinyurl.com/y68vgjgl
https://tinyurl.com/yxfhhpqh

What do you think of it ? Is it worth it ? Do you have advises ? Is it possible to find more accurate description/pictures ?

Regards,

CH Hamon

Cedric,
whilst you have parts like that off the car you can not drive the car. Unless there is a big problem leave this sort of thing until you have completed all your 30k-mile servicing, maintenance and repairs and done a 12 months of year round driving.

Driving the car will at the moment help more than any small increases, if any, that this type of thing will make to your car at the moment.

Checking the carbs and linkages are fully functioning would give more benefit and would be needed to see any real gain from tinkering/reprofiling with the manifold.

Did Aldon chaps adjust your carbs on the RR?

How many miles are you getting from a pint/litre use of engine oil?
Nigel Atkins

I know, I know, the basics first... ;)
But it looks like an "easy" thing to do, and a perfect excuse to buy a grinder machine :p

My oil consumption is slightly higher than this... Need to check it precisely
CH Hamon

I you want a good (and long) winter read on tuning 'A' series engines get a copy of David Vizard's Book

'Tuning the A series Engine'

That should tell you want you questioned and probably confuse you as well as to the next step - and the next step etc, etc, it never ends !

You noted that you have K&N's and a tubular exhaust - worth a check that the carb needles have been changed to suit the improved breathing. Moss parts book list options for both fixed and bias (sprung loaded) needles - page A22 in the copy I have.

If you are playing with the carbs its worth checking for play in the spindles (air leaks)and if you have bias needles there can be wear in the jet tubes (all part of a rebuild kit).
I don't think grinding out the manifold would be top of my list unless I was carrying out head mods as well.

R.
richard b

Cedric,
good to meet you on Sunday, hope you got back to London ok, I've got bits to do over the winter with my carbs, ticking over too fast, think it might be wear in the throttle spindle, trial and error though !
Scott Coe

Don't do anything that will take the midget off the road over winter that's when you get some of the best Spridget driving opportunities. Less horses, cyclists, walkers, motorbikes and doddery old classics, bimbling to a meet or show, on the roads at this time of year. Plenty of dry and sunny times too, often more pleasant weather than in the other three seasons and the carbs love the crisper air too.
Nigel Atkins

Both my Spridgets are safely hibernating for the winter now. First salt on the road on Monday here so they won't be out till spring. It's a perfect time to get it off the road and do some jobs.

I did a bit of work to the inlet manifold when I rebuilt the carbs earlier this year, there is a bit of info about it in Vizard. Whether it makes any difference is anyone's guess!
John Payne

Cedric,
if you want to tinker and improve your car then Daniel Stapleton's book
"The MG Midget & Austin-Healey Sprite High Performance Manual", is a good read.
Available here:
http://www.amazon.co.uk/gp/offer-listing/178711001X/ref=tmm_pap_new_olp_sr?ie=UTF8&condition=new&qid=&sr=

You may also like to try Peter Burgess' rolling road the next time you need your Midget set up. He knows our cars inside out.
Jeremy MkIII

You all want me to read more: is my English writing so poor ? ;)

>>> Yes Richard, breath out has been slightly improved by PO, but not sure anything has been done for the breath in: that's why I was checking how to do it in a fast, cheap and simple way.
(As said by Nigel, I should first concentrate on servicing the car properly for few months before looking for big improvement)
=> For the needle, do you think I should go (if not done already) for H6 or AAQ ?

>>> Hi Scott, drive back was perfect: under the sun and before the night :) Look like we will be both busy this winter :)

>>> Hi John, no garage sadly for the Midget... And as said by Nigel, sunny and cold journeys are great in the Midget ! But you're right, I try to avoid salt as much as the plague...

>>> Hi Jeremy, thanks for the book ! It is definitely in a corner of my head to go to Peter Burgess with the Midget "one day :)". But I would like to have better compression value before that, which mean engine out first... Which mean I will wait to need a new clutch :)



CH Hamon

H6 needs centering in the jet. AAQ has a bias spring, does not need centreing, but does rub lightly on the jet and will wear both jet and needle over time.
Rob
MG Moneypit

Cedric,
as I remember it you have K&N air filters and a standard(?) exhaust manifold - so it could be that the needles have already been changed for the K&Ns.

You need to look at your tags on your carbs and see what model(s) you have fitted, obviously they should be a set with one 'F' and one 'R' of the same number but never assume, then you could look at what normally would be in them for K&N or normal. Unless the needles are totally wrong or very worn there is little point fine tuning if your car is not at basic level. Time to teach you a technical term and help with your English - what you are trying to do at the moment may be valuable later but now is like - a fart in a colander.

;)

Nigel Atkins

Cedric--when you went to Aldon's did they have their sniffer up the exhaust---If they did, what was the result of that
William Revit

Ah, no garage. Then better to use it regularly and protect from salt as best you can. Any car sat outside in the winter and not used is going to suffer.
John Payne

I know Nigel is going to be unhappy, but I went to remove the carbs tonight...
I let the intake manifold on, as it look like it has been slightly rework already at its connexion with the carbs and with the head, and I could feel any sharp edge...
Some pictures, no really bright, to get your opinion

= Is it the original intake manifold ?
= Does it look modified ?
= Do you recognise my exhaust manifold ? Couldn t find any plate....


CH Hamon

more


CH Hamon

last


CH Hamon

Yes Willy, they did put the sensor on the exhaust. Sadly, they don't give any paper on these records, and I forgot to watch/ask... Still a lot to learn !
CH Hamon

Regarding the carbs, I didn't remove the needle, but it not a bias one. It also look like I have the "classic" spring for the piston (not red or blue)
= Any advise on the spring ?
= Also, it looks like I have a lot of burrs around the piston guiding (circled in red): is it "normal" ?

Good night :)


CH Hamon

The inlet manifold looks fairly standard.

The exhaust manifold is not standard, but it’s not the much-favoured Maniflow version.

The burrs in the carburettors are fairly normal. I don’t think SU spent that much time cleaning up the castings when manufacturing them in large numbers.
Dave O'Neill 2

Cedric-good morning
The step in the carb in the red circle can be cleaned up and also further into the carb where it joins the round bore can be cleaned up and blended in, polishing isn't that important, more the blending to get smooth flow--actually some people prefer non polished as it helps preventing the fuel from de-vapourizing and sticking to the housing BUT DO NOT touch the bottom horizontal step at all,--changing that at all will wreck the carb.
Manifold----are your carbs 1 1/4" or 1 1/2"
That manifold appears to be for 1 1/2"
You need to measure the bore of your carb, and the diameter of the manifold there
"If" the manifold is 1 1/2" and the carbs are 1 1/4" then an aluminium tube sleeve needs to be epoxied into the manifold so that it all matches up and then blended back into the bore of the manifold
"if" it already matches up then it wouldn't hurt to blend that step in the manifold bore in a bit, not too much though, better to keep the tube as long as possible, just roll that edge over into a rounded shape where it enters the barrel
Main issue is to measure the carbs and manifold
Also in that 3rd manifold pic ---in the pic it looks like the manifold is sitting lower than the port in the head, it might just be the angle the pic. was taken from ,but if it is low there might be a bit of wriggle room on the mounting studs to lift that up in line, even if you have to manufacture some adjustment on the stud hole with your best round file
willy
William Revit

I think the third manifold photo is showing the locating ring.

Dave O'Neill 2

Thanks to both of you for your comments. Might sounds silly questions, but I guess you get use to from me :) Thanks for you patience and support !

Concerning the size of my carbs and manifold, I didn't measure... Will do !

I will try to remove the burrs then, just wanted to be sure there is "no risk" by doing so
=> Is the piston guided by sliding on the suction chamber (red area on the sketch) more than sliding on the carb body (blue area) ? My concern while deburring was to risk to worsen the sliding precision of the of the piston... (if that make sense)

=> Concerning the spring, what are the pro/cons of going to red and blue spring ?

=> Concerning the needle, bias or not bias, what would you recommend ? From below comment, I can note that bias doesn't need adjustment but worn the jet. Any other advise ?

=> Last thing... Why everywhere they say that you have to mark the relative position of piston/body/suction chamber before dissembling ? As the piston has only one position to the body, and suction chamber also one to the body (or two, at 180*)....?

Thanks !
Cedric



CH Hamon

=> and... What about the screw of the butterfly ? Are they really disturbing the flow ? Should I change or grind them ?

My head is full of carb stuff :) Finally understand a bit more how it works, same learning curve as the ignition circuit at the beginning of the year, for those who remember ;D
CH Hamon

As you have gone this far you might as well remove the inlet and exhaust manifold and check them and how they line up to the ports and the gasket.

Also clean and if required overhaul the carbs.

I do not know what a "classic" dashpot spring is, I think the bit of blue or red on the springs goes away or I might be imagining/false memory of how the springs are marked or coloured. You would only need the standard spring to your carbs. The tag number should relate to the carbs fitted (unless the tags have been swapped).
Nigel Atkins

Spring and needle I can do them when the carbs are on the car, so I think I will stick to grinding for the moment, and put the carbs back "ASAP" to be able to drive the car when I want :)

I was surprise that the manifold didn't look "so bad" in term of flow, and pretty well adjusted to head and carbs
= What are the hole for, perpendicular to the flow ?

They are also some nice pictures there : http://www.retrominisltd.co.uk/index.php?main_page=product_info&products_id=1240
CH Hamon

Cedric,
I missed your recent posts.

You have access to much of the information, such as John Twist videos, the Driver's Handbook, Workshop Manual, SU website, mgb-stuff website, ect..

I will email you some information on some of the questions you have asked but the other posters will have to help you with the rest as it's beyond me.

I'm not sure why the dashpot position is important as both are circular unless it is to keep the relative position of each to allow for existing wear. There are three fixing screws but I can not remember if you can get them wrong but I don't think it would be 180 degrees out.

What is important is to keep the dashpot and piston as the pair they left the factory (for red area) and not to mix the pairs.
Nigel Atkins

Cedric,
you have (e)mail - and more on the way
Nigel Atkins

As Nigel says the main thing is to keep the cover and piston in sets with each carby, best not to mix them up
Spring colours are rated in strengths so that they can be matched to the engines performance---The whole idea of this is to get the piston to maximum travel just before the point where the car is at max. power
Your car could be red or blue depending on how it's been set up --which needles it has and what size the carbs are ,etc
If the car isn't stock standard ,which it's not it could have been set up with a combination of spring/ needle to suit
We could take a rough guess on the needles if we know the size of the carbs and what needles are in there, but I'd imagine if it was far off Aldons would have said
The carb piston is guided by the centre tube that the damper runs in,up into the cover, it shouldn;t touch your red/blue spots in the pic
Be vary carefull cleaning the red area as that relies on a close fit to get correct suction to pull the piston up
Also in the earlier pic of inside the carb. was that piston right up, it should go up further than that, if it won't go up any further ,try it with the damper unscrewed out of the top of the cover , it could have the wrong dampers in there
willy
William Revit

Your carbs are 1-1/4" HS2.

The 1-1/2" HS4 will not fit your manifold, as the mounting holes are positioned diagonally, rather than vertically.

It is possible to fit the earlier H4 1-1/2" carbs to a Spridget manifold, but I can see from your picture above that you don't have H4s.
Dave O'Neill 2

Query regarding needle types - bias are spring loaded to improve self centering ? - fixed have no side ways movement - they are not interchangeable. So you need the correct type for your carbs.

Manifold looks like a standard 1275 item to me.
As Dave O' noted there should be inserted steel alignment rings which locate both in the cylinder head and manifold to correctly position the manifold onto the head.

The dashpots do not completely rise clear of the carb opening and do therefore sit down a bit into the airflow - see D.Vizard A series tuning book, chapter 7 carburation (page 117) where he specfically notes this (and his mods if you really want to ?) + lots of other carb mods including the butterfly screws etc (if you really want to !)

Manifold shaping - again D Vizard book covers this Chapter 8 page 163 improvements to the standard Leyland twin carb manifold - I did carry this part out when I ran twins but can't confirm if any extra power may have been generated.

Happy grinding !!

Richard.
richard b

Richard,

IIRC the biased needles are very lightly loaded so they contact the side of the jet and don't run centrally as older needles did. The reason was that it was found that if the needle wasn't properly centred it effected the fuel mixture so the solution was to bias it to one side.
David Billington

David
Yes you are correct - I always thought the idea of rubbing lightly and wearing the jet and needle was a rather retrograde step to placate poor servicing standards.
It is noted by some that bias jets/needles should be replaced between 20-30,000 miles.

R.
richard b

If only I had a memory, I get the feeling I read somewhere the bias needles were for emissions(?) (at idle(?))?

The bias (on mine at least) is quite pronounced so I can imagine quicker wear. I've not seen where it actually has which way the bias should be on different carbs but there are markings to show direction.

I've no idea if you can can change bias to non-bias just by changing the needle locator and screw.

More important is - the bonnet release cable, is it secured an roted correctly or just the photo angle?




Nigel Atkins

Cedric
I agree with Dave that your carbs are most likely 1 1/4', but it would still be interesting to compare the diameter of the carb and also that of the manifold where they bolt up together
I learnt a long time ago not to take anything for granted, measure it yourself is the only way to go
William Revit

That manifold looks bigger than 1 1/4" from here
William Revit

Willy,
5.5" (140mm) on my screen, seems excessive! and times two, they must be off a very big truck or boat.

Nigel Atkins

Coincidentally, I’m working on some 1300GT (ADO16) carbs, this afternoon.

The manifold looks very much like Cedric’s, other than having the larger flanges which can be re-drilled to accept larger carbs.

The opening measures just under 1.5” at the face, tapering to 1.25”.


Dave O'Neill 2

Some update, as I see that you are getting more and more interested here :)

I think my piston can go all the way up: picture was taken at random moment ;)

As you guessed, my carbs are 1 1/4, measured ;) Funny enough, the "brackets" of the K&N are....31.0mm ! Already loosing 4% of air intake there... Might be even more, if you add on top of it the play in the screws...


CH Hamon

I have even more bad news:
- I didn't start the grinding, as my cohabitant is watching TV... But the Vizard book is soon on its way :)
Couldn't go to the car to check the manifold, due to weather... but tomorrow is expected to be nicer ;)
Can't tell you if my needles has been changed, as they are blocked in the piston, both of them
=> Any ideas how to get them out, without putting pliers marks on them ? :p


CH Hamon

Dave, i found this discussion on the MGexp website about manifold
Message #6 looks particulary interesting...
https://www.mgexp.com/forum/mg-midget-forum.3/flow-disruption-in-intake-manifold.3286679/
CH Hamon

The needles can be a bit difficult to remove especially if the securing screw has been really overtightened as it forms small burrs on the brass needle stem that makes withdrawing it difficult.
Ensure the securing screw is fully undone and apply release fluid into hole.
I have used various methods but all risk potential damage - firstly I try banging the base of the piston down onto the edge of a hardwood work surface - well only a part of the base avoiding the needle obviously ! this often shocks the needle to move.
If that fails I wrap the needle in fine grade wet and dry paper and hold it in soft jaws in a small vice and carefully ease it out.

Do your K and N's have any very short stub stacks within them ?
richard b

Dave---That's the area I'm talking about, it needs a piece of aluminium tube 1 1/2"od x 1 1/4" id with a taper to suit the chamfer in the manifold epoxied in there to match up with the 1 1/4" carbs and then blended into the manifold runner--
That step out after the carb. destroys the airflow and causes a soggy throttle feeling around cruising speeds
Someone on here(can't remember who)had an issue with it about a year ago and Peter B diagnosed the faulty manifold causing it.
Maybe a call to Peter would confirm that-
Cedric--All them little bits ,like the casting flaws in the carb body, the manifold step and your K&N "bracket" mismatch,-although each on their own are minor, together they all add up to a loss that can be easily rectified with a bit of fiddling at hardly any cost, if you've got the time to play with it and you seem keen to do so you will get the benefit from it, It's normal race car preperation stuff, it may be small and hardly noticeable but in your head you'll know it's right

willy
William Revit

Cedric

Yes, very interesting.

Vizard also talks about anti-reversion, as you will see.
Dave O'Neill 2

Cedric when I bought my race car the previous owner had done the full Vizard treatment on the carbs including halving the throttle spindles , wafer thin butterflies counter sunk screws soldered in and epoxy ramps to the bridge -it ran like a dog except flat out so don’t be tempted to go too far for the road ! Incidentally when I eventually took the head off it had obviously ingested a throttle screw at some point with perfect impressions in the combustion chamber.
I
Mike Fairclough

Mike you are spot on with description. It is the epoxy ramps to the bridge that ruins the air/fuel mix. Whilst airflow does increase throttle response and indeed afr at full throttle settings will suffer and make the engine almost untuneable and produce less power. On many occasions we have chiselled the epoxy resin off and achieved remarkable transformation! The same obtains for polishing the inlet manifold and making what seem like sharp changes of shape into well radiused shapes; fine for airflow but death to homgeneity of air fuel!
Peter Burgess Tuning

Rich,
I think the stub stacks are as in the photo and said to be 31mm(?).

Peter had me looking the meaning of a word up again, and I still don't fully understand the explanation, again, my head hurts now.
Nigel Atkins

Hi Cedric, I dont post many comments on this site, it has taken the last comments from Peter Burgess and Mike Fairclough to make sense about the journey that you are looking at taking and as far as I am concerned they are 110% correct. If you want to modify the car look at bolt on modifications ie a Hif 44 carb on a Maniflow manifold ,a modified Mg metro cylinder head or a well modified Midget head (be carefull on how modified),1.5 : 1 rockers, Aldon modified distributor and perhaps as Dave Oneil said a Manilow exhaust manifold/ system. When you get your Vizard bible read it carefully it is full of usefull technical information if you get the blue covered copy, the rest of it read it with an open mind because it is full of its, buts and maybe's.I hope the I have made sense. Just a bit of back ground on my self and had my fist Spite in 1971 and Raced Spridgets sor 27 years and have built many succesful race cars .just remember to keep it simple.
TONY GRIFFITHS

Morning :)

Thanks for all your feedback, they are really valuable. It is what is great here compare to books: feedback of people who did modify their cars, drive/race them and give objective feedbacks.

I have two objectives at this job: get to know better the car (how it works, spec and condition of the parts) and make it smooth to run.
I will be happy with a "Fast Road" configuration of the car, to re-use Peter Burgess head modif scale: I am not looking for a racer or a certain value of BHP, just a smooth and well going car :) Hope that's help to indicate you what I am looking for, and orient your advises :)

=Concerning the needle; i finally got one out: AN ! I bet the second one is AN too; and might be there since....long time !
> I think I will buy H6 and give it a try

= Concerning the porting, I was thinking of: removing casting/machining burrs in the carbs, change/port the screws of the butterfly, make radius in the manifold at the bridge holes and at the champfer (no epoxy)
> What do you think ?

As said previously, and from my lectures, I don't want to have better flow IF the same modification decreases the air/fuel mix
> What should I do/not do to keep a good mix ?

Anyway, I measured my head: the intake is 31.2mm at its largest (just after the ear for the intake manifold) :)



CH Hamon

Yes Richard, Nigel is right: the short stub stack is screwed on the carb on the picture. I should find a way to take better pictures... :)

I also removed the exhaust manifold: not so much soot "to my opinion", even if I don't know when it was cleaned last time... Also, the exhaust manifold has "bigger squares" than the head, so I don't think I will do anything there: flow could be improved for a racer, but my Mustard will stay like this ;)


CH Hamon

Under no circumstances radius the bridge, ne touche pas :)
I would also be very, very wary about radiusing the holes to the balance pipe in the manifold .

Ne touche pas is a phrase we learned when we were 14 staying in Paris and visiting the L'Ouevre, every exhibit was called 'Ne Touche Pas' according to the guides/guards present, small wonder The Mona Lisa winked at us like that!
Peter Burgess Tuning

Cedric-
I think there might be a little confusion here with the word 'bridge'---

"
= Concerning the porting, I was thinking of: removing casting/machining burrs in the carbs, change/port the screws of the butterfly, make radius in the manifold at the bridge holes and at the champfer (no epoxy)
> What do you think ?"

I think you will find that the epoxy ramp to the bridge that Peter is speaking of that stuffs things up, is, filling the bottom of the mouth of the carby up so there's no step in the bottom where the jet tube is there--why anyone would think that is a good idea is strange

i still think it's beneficial to match the manifold face to the carburettor bore
Reversion isn't an issue with what you're doing and even on a racer it's usually a sign that the manifold or ram tube is too short

willy
William Revit

Good french Peter ! You might also have the "softer" version: "On touche avec les yeux !" (touch with your eyes)
Hope you still enjoyed your visit despite the stressed employees overwhelmed by Asians...

Willy, by "bridge hole" I meant "holes to the balance pipe in the manifold" (thanks Peter !). I am not too bad for technical terms in french, but it didn't transpose to english (yet).

So, for better air/fuel mix, good road car performance and not annoyed Peter when I will go North for good tuning (after having sorted my low compression and oil consumption issues - might be linked), I will leave the manifold un-touched :)

(Willy, if I ever live down there with the Midget, I will put some epoxy and bring you the car for a good tuning ;) )
CH Hamon

Cedric

When Peter was fourteen, I think there were far fewer far-eastern (Asian) visitors to the Louvre.

No offence, Peter ;o)
Dave O'Neill 2

No offence taken Dave :)
Cedric, my schoolboy French was ok for requesting basic staple food products such as biere blonde, my biggest problem was to buy a Peugeot keyfob for my Dad ( a lifelong afficianado of the make until I got him to buy an SD1), took lots of gestures and drawings to work out I really needed to say....je voudrais un porte-cles s'il vous plait...still in memory 48 years later
Peter Burgess Tuning

WARNING: Thread Drift!
"took lots of gestures and drawings "

Reminds me of buying a reindeer skin from a group of Sami (Laplanders) in northern Finland in 1968. Involved rushing around in the snow making antler shapes over my head with my hands. I suspect they knew exactly what I meant but pretended not to as I became more and more frenzied in my attempts to impersonate a reindeer, including death throws and being skinned and hung on a drying rack. Eventually they could no longer maintain their dead-pan expressions and I successfully bought one for 20 Kroner
GuyW

I think you have my story beaten hollow there Guy :)
Mind you, on a school trip skiing in Austria ( I didn't go on that one) a teacher sent the school headboy to go to the chemists to buy some cotton wool. After a long time the lad came back with a box of tampons, I wonder what gestures he was making :)
Peter Burgess Tuning

Cedric,
with the exhaust manifold holes just make sure there are no overlaps with gasket and head. My previous exhaust manifold had a welding snot on the inside which partially closed the aperture down a bit.
Nigel Atkins

Thanks for your comment ! I promise I am not doing the math to try to guess your age :)
Speaking with hands and mimes are THE only international language ;)

I did disassembly my carbs, and the list increased: my spindle axes are pretty well machined by the body, so I will go for new ones too. I have t check if the new ones fits well, otherwise I might fit bushes... I am also hesitating to purchase new jets, as I don't know how old they are, and I read that the fuel line can collapsed from inside and give inconstant fuel delivery... But all small amounts together start to make a big one :P

My Vizard book didn't arrived yet, but I came across this picture of piston modification:
What do you think ? Is it needed or useless ?



CH Hamon

Mine had that too again from the Vizard book . I did that on another set of carbs myself but never did a back to back rolling road test I’m afraid , just following what everyone else was doing with theirs at the time
Mike Fairclough

I am with Mike on this one. Haven't seen a difference to be honest. In mild tune I don't think you will get any benefit from carb mods. Once you get a good head on it, hairier cam and get the cr up you may see a benefit from improving the shape of the spindles. Messing with the butterfly is a waste of time and can lead to poor closure of the butterfly at idle.
Under race use on a Moggy Minor restricted only by running a single 1 1/4" carb the largest gain we achieved ( bear in mind the engine was strangled with the small single carb) was removing the spindle and butterfly and having a direct pull on the carb piston to control air/fuel flow. It was in the region of an extra 7bhp at the wheels. Worked well as we won the championship we were in!
Back to back tests on a well tuned 1275 engine in a Moggy (large inlet valve head, 10.5:1 CR and 286 cam) 1 1/4" twins sharper to 4000 rpm then single HIF44 was better and made a few bhp more.
It is nice to play but the biggest benefit would be three angle seats, extra angle on underhead of valves and smooth the valve throats to get rid of sharp edges and increase CR.
Peter Burgess Tuning

Morning,

Thanks for your feedback, all make sense... I guess :) Not that I have experience to argue for or against :p

Still good for me and the carbs to be cleaned,changed wear parts, put new needles. They were running good, but didn't get check since a while I recon, as the needle were stuck and spindle axes worn...

I will then not bother too much with grinding, and start to save £500 for next winter project ;)
CH Hamon

**Aparté**
I came across a classic car yesterday evening, looking pretty much looked after. I thought it was a Renault 4CV, but wondered who in BML's country is keeping a French classic...!
Now that you talk about Morris Minor, I just realised that I confused the two names "Minor" and "Marina", thinking the first one has the body of the second one...
Minor looks pretty indeed! As do the Renault. Who copied who ? :)
CH Hamon

The Minor was introduced in 1948 and was designed by Alec Issigonis, designer of the Mini.
Dave O'Neill 2

Both cars were conceived during the Second World War, France had visitors in at that time but who knows what was exchanged or seen by each company before this.
Nigel Atkins

Cedric,
you must bear in mind that what is good for a race car is not necessarily good for a road car. Race cars generally are for very short bursts of occasional full-on use (and testing, qualifying). Road cars generally cover overall a much wider range and (hopefully) more frequent and longer use - chalk and (French) cheese.
Nigel Atkins

If I remember at the weekend I’ll dig my carbs out and put a photo up of the ginding/butchery
Mike Fairclough

Just a quick photo of epoxy ramps and thin butterfly’s , probably fit for the scrap bin


Mike Fairclough

Mike

Put them on eBay and mention ‘Speedwell’ somewhere in the text. Someone’s sure to buy them 😀
Dave O'Neill 2

Nice idea Dave , reckon I’ll get enough for an engine rebuild .
Mike Fairclough

Ready for my first carb's tuning session ! Hope my neighboors don't forecast to sleep late saturday... :)


CH Hamon

Good luck Cedric, hope it runs smooth !!
Scott Coe

Wire coat hangers used to be so useful for so many jobs on a car. 😊
Nigel Atkins

What do all those tools do?
Dave O'Neill 2

Thanks Scott !

Nigel, my girlfriend keep asking me where they all disappear... I keep pretending I don't know :)

Dave : https://mgaguru.com/mgtech/carbs/cb130.htm

I was reading a lot in the archives about how to set-up dual carbs:
- Flow meter (all different models, pro and cons)
- "tube-in-the-ear"
- and SU tool kit
- others I didn't came across

I went for the last option :) Time will tell if it was wise or not. You should be able to tell, according to the messages I will post this weekend ;P
CH Hamon

(I went for the 3rd option obviously... Added the 4th one after I wrote the message...
Should increase the EDIT mode to 10min for non-natives - or dumb in writing :p )
CH Hamon

This thread was discussed between 30/10/2019 and 29/11/2019

MG Midget and Sprite Technical index

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