Square port or round port head?

[mattcogg]

hi again,
After some good advice a lot of people have told me to port my head. Now I know this sounds stupid but can you a port a square port head. The reason for this is I have picked up a recon head and I don't really want to get rid of it. I also get the impression that porting heads is very expensive but seems to be very worthwhile. Is it basically the idea that petrol can get faster into the engine. Does anyone know exactly where there is any reliable and good head workers in the south west ie Bristol as I haven't come across any.
Thanks again
Matt

[Aragorn]

hrm i know the 1.4 heads (ie square ports) are worse than the catherdral ones

i dont know how big the difference is - u may even find a ported square head is still more restrictive than a cathedral head as standard


if your gonna port a head i'd defo reccomend doing a cathedral head since for the cost u really wanna get the biggest bang for buck

[mikeoxford]

if its going in a mchine to be worked anyway - can they change the shape of the port openeings?

just curoious - i havent a clue so i dont care if im wrong :twisted:

[mix n match]

I dont think that a square ported head will ever be as good as a cathedral ported head because the metal between the ports and water jacket is only so thick, meaning that the ports can only be enlarged so much. So the biger they are to start with the biggrt they will end up, it would be very bad to brake through into the water jacket :o

This is my understanding of it anyway, if its wrong i will stand corrected :wink:

[rgv_stu]

you can port a 1400 head - i have just done mine as i was bored over christmas ;)
but i will be putting a 1200/1300 head on later as it is a better head

mike - no you cant really reshape the ports - unless you got a good welder.

the arch shaped ports run straight in and down onto the valve where as the 1400 head the ports come in the side of the valve and corkscrew around and down.

i hopefully will have made it a bit better ,but i will be using the standard head / pierburg carb until my new rings/bottom end have bedded in.
then i will be going over to a 1200/1300 head with my spare weber and possibly a cam.