you can't put RS springs into a R head without machining. The spring seats and caps are different. 7mm vs 6mm. I'm not sure on the valve stem length.
The sagem ECU (if that's what you have) can't handle the cams from the RS properly and although I've never tried, I don't believe you can remap them.
To take full advantage you need to use either the complete RS head, Loom and ECU or the R head with RS cams and stronger valve springs (catcams do some I think) with the RS ECU and loom.
You also need to bore the R head behind the inlet cam pulley so you can fit the cam position sensor. (there is a blank there)
confused yet?
I stand corrected, Welshpug is right. was getting my J4 and J4R's mixed up
The sagem ECU (if that's what you have) can't handle the cams from the RS properly and although I've never tried, I don't believe you can remap them.
To take full advantage you need to use either the complete RS head, Loom and ECU or the R head with RS cams and stronger valve springs (catcams do some I think) with the RS ECU and loom.
You also need to bore the R head behind the inlet cam pulley so you can fit the cam position sensor. (there is a blank there)
confused yet?
(30-09-2015, 01:23 PM)welshpug Wrote: RS stems are not smaller than R, they are smaller than the old J4, Mi16.
I stand corrected, Welshpug is right. was getting my J4 and J4R's mixed up