2.2E port options
 

Got a quick question. I searched and didn't find exactly the answer I was looking for. I'm building essentially a 2.2E motor in a 2.2T case.

I have two head options available. Tried and true 2.2T heads which I know will work but they need valves replaced. I also have a like new set of 2.7S heads (35mm ports) that I could use. I am running webers.

What is the effect of a larger port on an E motor like this? Obviously it works well on a more radical motor but will it detract from an E spec motor?

Thanks for your help.

Use the 2.2T heads to maintain port velocity using E Cams.

The 2.7 heads would be OK for an S-cammed engine or better.

Thanks Steve. That's what I was suspecting might be the answer. I was hoping otherwise. My 2.7 heads are like brand new. Looks like I will be sending my 2.2 heads off and selling the 2.7 heads.

Sorry to hijack, but is the cam the main factor in the decision on the port size? Would you still choose the stock size ports on the 2.2T heads if you were building something like a 2.5 or 2.7 with the same E cam?

Thanks in advance

Ok. Another question. Since I'm going to rework the 2.2T heads anyway, is there any advantage to opening the ports at all? I understand that 35mm is too big but is it worth porting out an extra mm or so?

My 2.2T was rebuilt long ago with 2.2E pistons and cams. The heads were not ported. It runs fantastic.

I am a proponent of smaller than larger when it comes to port sizing for anything but an all-out track car. Port velocity helps so much in low-speed performance where most of the time is spent. More gains here with small ports compared to the high-rpm loss from a choking effect.

For the very little experience I've got what I don't get is that even if T heads have got small ports, the valves are still HUGE. So the flow will need to slow down a lot before entering the combustion chambers. If it was possible, wouldn't be better to match the smaller ports with smaller valves?
luca