Cam choice for tu5jp4 engine - Saxperience

simo8028 · 16th August 2018, 08:44

Hi all

I have a tu5jp4 engine and looking for at set of cams.

I´m running C2 VTS alloy inlet, 4-1 manifold race-cat and sports exhaust. Also i have a set of J4 adjustable pulleys. I wont´t be replacing the valvesprings, unless it´s absolutely necessary.

I´m currently looking at stock J4 cams, Newman PH3 or Catcams 1322703.

I´ve looked at a few forums online and my main concern is valve to piston clearence.

My aim is around 145 bhp, with decent midrange tourqe, as i will be driving the car everyday.

Obviously the car will get a remap after the cams are fitted.

Kind regards
Simon

Chipwizards · 17th August 2018, 18:29

There's very little clearance on a JP4.
JP4S and J4 have small cutouts in the pistons to allow for a sloppy timing belt on the stock cams which allows a little scope for bigger cams.
Whatever you choose, proceed with extreme caution when doing the timing.
Also consider that the valves are closest a few degrees after TDC, not at TDC.

simo8028 · 18th August 2018, 08:20

Thank you for your reply.

I am aware of the tight clearence, however all the cams I’ve listed should clear the pistons at TDC but obviously I will be carefull.