Board logo

Zetec BT RS head and cams
Robbaa - 27/11/17 at 06:21 PM

Evening gents

Ive got a Zetec blacktop running jenveys at the moment which is making 157bhp.


Ive done some research and purchased a set of piper cams with 270 degree lift and some new pulleys.

i also have in my arsenal a ported and polished head from a mk1RS focus.

what im after is if anyone knows if i will have any issues fitting this head to my blacktop and then dropping the piper cams into the RS head?

its staying N/A.

im praying this might make it past the 200 mark once its remapped again.

anybody have any thoughts or forsee any issues?

cheers

Rob

[Edited on 28/11/17 by Robbaa]


SPYDER - 27/11/17 at 08:10 PM

Hi Rob. If they are BP270 cams then 200hp would seem a little optimistic, even with your Jenveys and a ported head.
Do you know what compression ratio your new head will achieve on your existing block?
Are the RS head valves any bigger than blacktop ones? Will they foul the piston tops?


Robbaa - 28/11/17 at 12:19 PM

cheers for reply

im lead to believe the cr will remain the same. the rs pistons were longer but with a shorter rod equalling the same cr.

the exhaust valves are slightly bigger but i dont currently know if they will foul, i was hoping for some input


Robbaa - 29/11/17 at 11:55 PM

all good the ports are just wider thus more flow. what makes you think it wont make that power? there are other cams out there with slightly more lift but all the power is at the top end thus a bit useless


Paul Turner - 1/12/17 at 07:39 PM

The RS was a turbo, to achieve the 8:1 CR specified by Ford were the differences in the pistons/rods or the combustion chamber volume.

If the combustion chamber volume was bigger you will never get good power fitting one of these heads to a blacktop bottom end regardless of cams etc, if its in the pistons/rods you may be OK.