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Bunch of bananas? - Printable Version

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Bunch of bananas? - Duncan Grimmond - 19-01-2020

I'm looking for a four-into-one exhaust manifold. Does anyone have a favoured manufacturer in my area (N.Yorks)whom they could recommend?
Or someone with a manifold they don't want?


RE: Bunch of bananas? - Steve Jones - 19-01-2020

I've an old one you can borrow as a pattern, Duncan. It's been loaned to various people for the purpose and they've found that their local 'man' has been able to produce what's required. It helps if you supply the pre-cut plates for either end. Available from David Cochrane for not much money.

Steve


RE: Bunch of bananas? - Davemayle - 19-01-2020

Hi Duncan, I couldn't find one at a sensible price so used the tubes from a kids trampoline. 32mm diameter, and the right radius. Cost less than £20 including the manifold plate. I could have done a better job on the 'mermaids purse' junction but does the job!


RE: Bunch of bananas? - Nick Turley - 19-01-2020

I had a "tuned" (each pipe was an identical length) manifold made which was two's into one and then two ones into one (hope that makes sense).
It was a super job and worked very well.
This was made by Tony Law exhausts in Leeds ‭0113 271 5422‬ speak to Paul (he is very very good but it must be said a bit of a misery).
I think I took him a plate for the manifold and I took him the car.
Their work is good.


RE: Bunch of bananas? - Bob Culver - 19-01-2020

I suppose it is largely intellectual property and I have no experience, but in view of the low volumetric efficency the pri pipes often seem to me generously large.  Separation of successive cyls is very desirable but most books reckon a long distance is ideally and many moderns attain this. 


RE: Bunch of bananas? - Davemayle - 19-01-2020

One listed on eBay 223863384776


RE: Bunch of bananas? - Alan - 19-01-2020

I think the thing is , Bob, that anything is better than the standard manifold. I once spent a lot of time calculating pipe lengths and came to the opinion that the 27 inches as recommended by a well known seven tuner before I enlisted the computing facilities of one of the worlds largest aerospace companies, ( they didn’t exactly know about it) was about ok. In fact any multiple of this will do, so if those pipes look about 13.5 inches, then that will do. Agree about pipe diameter though.


RE: Bunch of bananas? - Mark McKibbin - 20-01-2020

Here is the Bunch of Bananas on my 1913 Bebe Peugeot so not a new idea although no amount of trickery can make these things go.


RE: Bunch of bananas? - John Mason - 20-01-2020

Duncan, I had a laugh at your expense on reading you wanted a four into one exhaust. (I knew what you wanted. A sports manifold) The reason I found it funny was that the standard exhaust manifold goes four into one but is not as efficient as it could be.
Sorry again I just found it amusing.

John Mason


RE: Bunch of bananas? - Duncan Grimmond - 20-01-2020

Nae bother John!
Steve, thanks for your offer, I'll be in touch.