Exhaust manifold

[Propshaft]

Hi. I have just got my hands on a 1275 midget engine I have acquired a hif38 carb and inlet manifold ,can I use the existing exhaust manifold or would it be better to use something with a bigger bore . Comments appreciated

[philthehill]

Unless you intend to change the camshaft from the standard Midget one - a standard Minor exhaust manifold (1098cc) with the inlet side of it cut off will suffice.

[Propshaft]

Thanks I was hoping that was going to be the answer . I am fitting it into a van just wanted a little more power

[philthehill]

Fitting the 1275cc engine will allow you to improve the rear axle ratio.
Here is a selection to choose from.[frame][/frame]

[jagnut66]

Hi,
The 3.9 is the one everyone seems to rate, I believe, if you feel the need to change that is.
I ran Abby (two door saloon model) with the standard 4.22 mated to a Midget 1275 and very well she ran indeed.
Looking down that list I think you should have a 4.55 at present but I stand to be corrected...........
Best wishes,
Mike.

[Propshaft]

Hi. You seem to be reading my mind was contemplating changing the diff ratio . I have a 31mm(11/4) tubular extractor manifold do you think this would be better than adapting the cast one off a 1098 , I don't intend any other tuning mods on this car . I relie on my TR 4 a for the performance side of my motoring

[bmcecosse]

Your tubular manifold will be fine - not too big, which is the mistake some make.