MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

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 - Witch tubular manifold?

I am looking for a tubular manifold. I own a 948 cc engine it is totally standard (with 123 ignition and K&N filters). The reason that I want a tubular manifold are the speed hums here in Holland. They crack manifolds; I just installed my third standard manifold in 7 years. I realize that it will take a lot of time to dial in the car and every modification makes a difference. When I put on the tubular exhaust I expect to have to go in and modify the H1 carb set and perhaps retime the 123 ignition.
Is the small bore Maniflow the one to go for, the cheaper Moss one, or Peter May Maniflow LCB exhaust manifold (roadgoing)


Flip



Flip Brühl 948 frog 59

flip,

Im guessing the pipes are hitting the ground when speeding over the bumps...

They used to make a "Pass thur" exhauste...(Not the proper term) ... But the EX tube ran into, thur, and out the rear end of the transmission tunnel... they are rare to find, ive only seen one once on ebay ... but Id think it could be re-made by hand... I think it was used mostly in race cars

the other thing that might help is to Over secure the EX system to the car... no give, completely rigid and solid... make it part of the car body... just guessing at this, as this is what I did to my truck, no more cracks devoloping ... 1 month now
Prop

DO NOT go fro the moss one!
It is dreadfull.

I don't know what diameter the small bore maniflow is.
I think this http://www.minispares.com/Product.aspx?ty=pb&pid=35078&title= is the one you want
Onno Könemann

Onno. Correct me if I'm wrong, but isn't the 948 one a smaller bore than the 1098/1275 one? The one on that link says it's for a 1275.

Bernie.
b higginson

It says it is a 1.5" inner Diameter that would seem fine for a 948.
Remember the A-series realy likes easy breathing

for a 1275 i would go for the 1.75"
Onno Könemann

Prop

What you have suggested there about over bracing it to the car is going to cause nothing but cracks.

LCB's tend to crack at the join in the two outer branches, which is a pain in the ass to weld properly once it does crack.

The actual manifold itself shouldnt be getting hit too often due to it being in relatively close proximity to the wheel providing you are road driving.

My suggestion is to add a flexi pipe to the end of the collector where it joins to the rest of the system. This means a lot less stress put onto the monifold and its studs should the system under the car get hit by the waste of tarmac our authorities have insisted on placing everywhere in an attemt to destroy our cars.

PeterJMoore

Maniflow make the best LCBs - IMHO
Dave O'Neill 2

Sorry peter,

Im not sure a flexiable exhauste system works, My truck had one with lots of rubber mounts and it contianly moved around blowing out manifold gaskets and cracking, to the point it took forever to get my truck to pass inspection...finally I cut out anyhing that would allow it to flex and made it part of the truck in ragid form... that was a month ago... no cracking or ex manifold head gasket issues and passed inspection after having made the exhauste rigid mod 3 weeks before... still tight

But that said... it is a unibody construction car, so you might have a better approach...perhaps it needs more flex so it can swing around independant of the car, while the truck is a body on frame and the exhaust system is rigid with in the frame not the body.
Prop

Prop, Peter means a flexible bit in the exhaust system itself and not just flexible exhaustmountings.
The flexible bit stops the engine-vibrations getting thrue the rest of the exhaust & brackets.

Like I had made on mine.


Flip, on my 1500engine I had a Peter May LBC manifold and had it modified with a flexible part between it and the custommade remaining exhaust because my Peco kept breaking of by the same reasons yours is too.
Once broken and welded it stayes weak and will go again probaly next to the weld.

Spoil yourself with a good manifold and custommade exhaust system or get everything custombuild at EPS (groningen).
Yes, its not cheap but replacing broken bits isnt either.



Arie de Best


My old Peco tubular manifold (fitted by the PO) used to regularly scrape the speed humps up our road. I've replaced it with a maniflow, which sits much tighter to the bottom of the car and I've only scraped it once or twice due to not slowing down enough.

The maniflow is a real work of art compared to the Peco; it sounds much nicer and flows better. The chassis had been slightly relieved to get the Peco to fit through, but it wouldn't have needed the modification for the Maniflow.

I think the Maniflow is great.

Mark
MarkH1

My vote for Maniflow (from Kim Dear) too.
Gary lazarus

Tank you gentlemen, So the Maniflow or Arie's is the one to go for. What is the price Arie? ( if you dont want to mention it here you can mail me..)

Flip

Flip Brühl 948 frog 59

Oh I gotcha... great idea

Ill have to look around over here for one of those flex joints incase my "Rigid" idea dost pan out on the truck

thanks

Prop

TUNNEL EXHAUSTE....thats what its called, several articals in the arcives, acccording to google


as it relatess to my 1st posting.... then it would never scrap the speed Bumps agian.
Prop

And an other part of the trick is to mount it as close under the car as posible.

2 MGB rear mounts work great
1 behind the seat in one of the original bolt holes
and 1 on the rear wher you have to grind a bit from the mounting bracket and bend a bit of steel bar to make a new mount.

mine is now rely tight to the floor but i never hear it on hups again
and my car is rather low.

i'll try to take some pictures later
Onno Könemann

Flip, my 1500 Peter May manifold was actualy a maniflow too.(ive sold it to Rolf from Groningen who was with us at Spridget 50 Gaydon).
Buying one of those and addapt it with a flexiblebit is (3 to 4 times)cheaper then a custommade manifold.
I had to as ther is no one suplying a decent LHD Kspridget manifold.
Arie de Best

Actualy im thinking of designing a carter-protection with build in/on exhaust protection as im planning to do serious rallying again next year.

I believe Irish PeterJMoore sells them for A-series spridgets.
They can be seen on his site.
Perhaps worth a thought for you too Flip?
Arie de Best

This is the type
The big advantage is that you only load the rubber bushes in pressure not in stretch.
Result you exhaust never falls off!


Onno Könemann

home made angle to the orignal holes


Onno Könemann

the same in the midle


Onno Könemann

And using the right clamps realy helps.
The angle of the pic is a bit wrong but the botom of the bolt is the same heigth as the lowest point of the exhaust.

It is a maniflow with a Magfic midget rc40 exhaust.
Fits perfect sounds great does not limit power and is affordable!


Onno Könemann

As Arie says

Sump Guards that we produce could also prevent your problem.

PeterJMoore

Sorry,

Forgot the photo :S

.......... and the hijack, I dont really like pushing business through the forum


PeterJMoore

Any idea where to pick up a quality set that's chromed?

Look at the attached piece of work.


TS Smith

yuck

that is all

Most chrome piping available will be done as cost effective as possible

In turn this will equate to the chrome plating deteriorating and peeling off within weeks.

Would match a hamper rack nicely though. :P
PeterJMoore

There are some good high gloss ceramic coatings.
Trevor Jessie

Oooohhhh Vary nice TS, Im a fan!

Treavor is right... Ceramic, Huge advances in the past 3 years

this is a vary popular one sold thur techline.com... called cermkrome...

also Jet hot makes a good one also

http://www.hotrodders.com/forum/cermakrome-vs-jet-hot-header-coatings-63990.html

http://www.classicchromeco.com/capscoating.htm


Prop




Prop

that looks like car porn TSS!

Flip
Flip Brühl 948 frog 59

good feedback... looks ok when new, but won't last. I've had powder-coated, painted, and unfinished, and they all seem to look the same over time. My Harley exhaust seems to hold up well though....
TS Smith

I just want to see the K&N filters on H1 carbs.
D Ramsay

Flip - give Maniflow a call. I did, and had a very informative talk with a chap who seemed to know what he was talking about. He spoke about pressure etc., which I only half-understood, and advised me to go for the small diameter pipe for a 948 engine. I told him mine is mildly tuned, and he still thought a larger diameter would not be appropriate.

Maniflow's number was +44 1722 335 378, the last time I spoke to them.
Nick

Prop, here's a "thru-tunnel" header design...

http://www.spridgetech.com/thru_tunnel_exhaust.htm
TS Smith

Thanks to everybody for the advices. I bought the Maniflow. Nice very nice tone and much less loud than the original. I can hear the dif and tranny now. Top speed is not affected; a somewhat richer needle is needed as pulling the choke ads 2 more miles. I do have the impression that acceleration is even a little bit better.
I encountered 2 problems:
-The damper sits to low and to close to the fuel tank. I tried every possible position; this was the one where the dif can’t touch the exhaust.
-The manifold is to close to the inner rail of the chassis. At first it was perfect. After a pleasant drive at top speed it sat to close to the inner rail.
What did I do wrong? How can I bend the maniflow manifold? I do not have a welding torch. Or do I have to change the front engine mounting rubbers?

Flip



Flip Brühl 948 frog 59

an other photo


Flip Brühl 948 frog 59

Flip,

what does Maniflow suggest when you contact them about these questions?


Maniflow: TEL: (01722) 335378
Email: info@maniflow.co.uk


Norm
Norm Kerr

I did sent them an e-mail an hour ago. The e-mail adres is maniflow at lineone.net

Flip
Flip Brühl 948 frog 59

Realy think about changing the rear mounting to a modified MGB mounting.
(as i posted above)
That rubber block will rip in 1 year and then your nice exhaust will grind over the street.

By making your own mounts you can position it way better to.

I mounted my exhaust as high a posible (your pic shows normal maniflow height)
As a result the axle can not drop totaly without leaning on the exhaust.
But this gives no problems when driving (though my car is lowered)

no help with the manifold though
Onno Könemann

Onno,

I ordered the MG B rear mounting.
Maniflow called me back! The advice is: slacken the engine mounting rubbers. I'll try.

Flip
Flip Brühl 948 frog 59

Eh?

So their manifold doesnt fit, and yet you have to slacken your engine mount rubbers to get it to fit.

Don't think that would rub too well with me.

Is it rubbing on the chassis leg itself or on the panel that the exhaust goes though (we have that metal totally removed for clearance)

What condition are your engine mounts in? Maybe a new mount on the manifold side would tilt the engine enough to allow it to slip on passed the chassis leg.
PeterJMoore

Sorry to come in so late on this and apologies if I've got this wrongbut my maniflow manifold (for the 1275) downpipe sits one in front of the other rather than side by side, therefore there is no problem clearing the rails.
Gary lazarus

Apologies for the quality as it was taken with my mobile with the car in the garage but as you can see, even though ot's also a maniflow, it is much more sensibly (to me) designed to fit between the chasis rails.
Bought from Kim Dear.


Gary lazarus



"So their manifold doesnt fit, and yet you have to slacken your engine mount rubbers to get it to fit"

C'mon PeterJ, there is slack enough in the engine mounts to put the engine in wrong.

Just undo all the bolts, lift the engine a bit and situate in a way everything fits and redo the bolts.
Alex G Matla

"Just undo all the bolts, lift the engine a bit and situate in a way everything fits and redo the bolts". That is what I did. I worked out well yes indeed.
My next manifold will be the one you have Garry!
How can I bend the last part of the 38 mm tube, just before the silencer, and without a torch?

Flip
Flip Brühl 948 frog 59

This thread was discussed between 11/10/2010 and 08/11/2010

MG Midget and Sprite Technical index

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