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MG MGA - performance headers?

Hi!

What performance headers do you-all suggest for rebuild MGA 1600 engine with 18GA cylinder head on. The head is ported, big valves, new guides
and Weber 40DCOE carb. Have anybody know something about the Monza chrome Headers ?
Martin

Like the one on Ebay? Vizard's book about tuning the A-Series has a ton of info about headers and what designs work in which applications. Its a great read!
Jeff Schlemmer

Martin,

This is the one I'm using... Big Bore and should be good for up to about 175 BHP.
The also fit with LHD cars (Not all will fit so be careful if your LHD)

Moss UK part STR633 £176.96

http://www.moss-europe.co.uk/MossUK/ProductList.aspx?SubSubCategoryID=MGA_UMGA-082

I like these as they come in two halves, so you can fit each pipe separately.

Don't forget to wrap them in the heat proof tape, makes a huge difference to engine bay temperature and is suppose to give you more power if you believe the sales pitch.

Cheers <MARK>
http://freespace.virgin.net/marka.hester/MGA_Twin_Cam_Home.htm
Mark Hester

You could do worse than modifying an MGB manifold (needs an angle grind on the face to pull the bottom closer to the block). It really isn't that bad a design.

Mark - love the headers (I use them on my Mk 2 Coupe) but disagree about the header wrap. An almost sure way to trash the headers in relatively short order. We had a TVR race car that rotted out the headers in 2 seasons using wrap. I prefer to suffer a bit of extra heat and not have to replace the headers periodically.
Bill Spohn

Bill,
MGA one's are a few inches longer, so MGB one's won't clear the round tube cross member under the gearbox.
Plus if you've got LHD, the steering pinion maybe in a slightly different spot, so better sticking with the MGA one's.... Having said that my moss one's needed stretching between the end two ports to fit.
MGB one's are certainly cheaper though... guess that's to do with volume sales.

We've used that wrap stuff for years and not worn out a set of extractors yet. However I have heard that argument before, so I guess it depends on how thick the pipes are to begin with. Or go for the Stainless one's if your worried. I had trouble with the weber getting too hot, but everything gets hot in Australia.

Cheers <MARK>
Mark Hester

Martin; Burgess book " how to power tune MGB" has a good chapter on exhaust systems. Cheers, Bill
w.g cook

Mark, you misunderstood me -0 I was talking about using MGB cast iron manifolds not tubular headers.

And you are right, some alloys will withstand wrap better than others - its just that by the time you find out yours weren't made of the 'good' stuff, you are shopping for another set of new headers.

The headers you and I use don't leap out at you as being non-stock (unless you wrap them ;-)

http://www.rhodo.citymax.com/i/non-rhodo/engine1.jpg

I doubt you'd notice them unless you looked for them.
Bill Spohn

There is an extractor exhaust manifold just come on to ebay - might be worth having a look - Cheers Cam
Cam Cunningham

That header (item 8040309167) won't fit an MGA (and certainly won't fit an Elva) although you can sometimes make an MGB header fit with modifications.
Bill Spohn

Hi Martin, I put an MGB iron exhaust manifold ('65 3 main) on my MGA 1500 in 1967, has worked very well since. I had to grind into the cast iron where the steering column goes by, about 3/8 inch and weld a plate over it. (Measure where to cut with fairly fresh motor mounts installed.) Match the intake and exhaust ports with the header using a competition manifold gasket. The stock MGB down pipes angle towards the driver door so it will require an angle pipe to correct for that. I had put a Thrush muffler and a short pipe to exit at the driver dog leg, it sounded fantastic!! Unfortunatly the local fuzz did not care much for it, so another Trush in series with the first fit nicely along the gas tank, a short chrome bologna cut tip works well and still sounds great! (The local fuzz for our neighborhood used to slalom with us, we were friend for years.)
The 1500 head had been modified at the same time after the Siebring Sprite mods, block notched for valve clearance, head trimmed .090" with rocker stands shimmed to compensate. I ended up using MGB needles and seats in the stock 1 1/4 carbs, very strong for a 1500. We had some fun!! I still have the car, it suffers from low octane fuel a bit but still is a joy to drive.
MGB iron header works well with some mods required.


























11
R.A. Carnes

Hello all,

With the MGA header as offered by Moss, what is involved in fitting the exhaust system. It would seem to follow that this is not a "bolt up" proposition. Does the factory exhaust fit in some fashion? What modification do you have to do?

Thanks,

JMG
John Greenlee

On a point raised in this thread the use of an exhaust wrap on a standard MGA manifold would I assume reduce the temperature in the engine compartment which has attractions especially for a coupe. But does this mean that the engine would run hotter because the temperature of the exhaust manifold will remain higher and cooling of the gases would take place further down the system in the pipe and silencer? Although built of cast iron would the higher exhaust temperature be detrimental to the manifold?
John
J H Cole

FWIW - I have heard of of cast manifolds cracking after being wrapped so caution might be advisable on a standard manifold. Cheers Cam
Cam Cunningham

This thread was discussed between 23/02/2006 and 03/03/2006

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