16-08-2022, 11:53 AM
A friend who has 60 years of tuning experience (mostly bikes) once told me that exhaust manifold design is not that important until you are looking above 5000rpm. With Austin 7's, I am of the opinion that the biggest advantage of a fancy exhaust manifold is that you are usually forced to also have a different inlet manifold, and that makes the biggest improvement.
My Pytchley had the complete set of Cambridge twin SU's, inlet manifold with balance pipe, bunch of bananas (as shown earlier in this post). Yes, it went very well but the temperature under the bonnet was high and access was severely impeded. I reverted to a standard cast iron manifold with the restriction bored out and a single 1" SU. There is no noticeable difference in performance and the engine is just as lively and free-revving. Accessibility is good and the fuel consumption is much better. The car is used on the road, perhaps if it was a competition car things would be different.
Whilst on the subject I have a Dante cast aluminium exhaust manifold but the outlet is very close to the position of the n/s radius arm and would require a very sharp bend on the exhaust pipe. Has anyone any experience of using the Dante manifold on a Box saloon or similar?
My Pytchley had the complete set of Cambridge twin SU's, inlet manifold with balance pipe, bunch of bananas (as shown earlier in this post). Yes, it went very well but the temperature under the bonnet was high and access was severely impeded. I reverted to a standard cast iron manifold with the restriction bored out and a single 1" SU. There is no noticeable difference in performance and the engine is just as lively and free-revving. Accessibility is good and the fuel consumption is much better. The car is used on the road, perhaps if it was a competition car things would be different.
Whilst on the subject I have a Dante cast aluminium exhaust manifold but the outlet is very close to the position of the n/s radius arm and would require a very sharp bend on the exhaust pipe. Has anyone any experience of using the Dante manifold on a Box saloon or similar?