So we strapped the Nissan 1400 4-1 Powerflow branch on the engine while on the bench and it ran beautifully! It felt really foot-loose. Ran through the RPM range.

All this convinced me to get one for my A15 in my own little GX. But I don't drive my GX like my brother drives his buggy. He literally drives it 'til it's gremlins get out. What I mean is he sticks to the higher RPM end. While ravaging the farm. I drive a little bit differently due to a lot of bad road and traffic.

- So I assumed a 4-2-1 makes more sense? I mean the original manifold was designed like that.
- Also, I was curious if those 100cc's would make a difference. I bored it to 77mm to be safe when I serviced the sub-assembly, but I mean, if I'm going to spend the money, shouldn't I be looking for an A15's Branch?
- Lastly, what size should I go for? I currently have a 57mm from where the 2 pipes after the original flange join.