Just help my friend to installed HKS 264 8.5mm In/Ex Cams on his CA18 S13 , it brought from Japan auction, it is a used item and it did not come with a cam card,
So I follow my own cams card come with my HKS 256 8.8mm , and it is included 264 9.0mm degree, I have found that both 256 and 264 max lifting is at the same degree, so to adjust the 264 8.5mm at the same way will be proper.
Everything straight forward, measure the max lifting degree as per my cams card, turn the crank clockwise only, double check the valve timing twice, replace the cam seal with new items, replace new cam belt, replace the front crank oil seal, replace the valve cover oil seal, replace the half moon rubber with 6061 billet aluminium custom made one, replace all the valve cover bolts to stainless steel invert hex bolts.....all done at once etc
The HKS 264 cam and tomei cam pulley is the only change in the set up, nothing more.
This S13 have factory cams before the 264 8.5mm, JDM CA18DET 8 port engine unopen, 550cc GTR35 injectors (resistor pack removed), GTR35 slot type AFM in 76mm OD tube suck thru set up, JDM 8 port ECU controlling factory vacuum tank and solenoid, nistune type 1 board, GTX2867R with 0.64 hot side on cast manifold, around 70mm dump pipe flange into 3" front pipe, no CAT, HKS Hi Power silent exhaust, 63mm intercooler cold pipe....etc
When with factory cams, the exhaust note is smooth bass almost no pulse.
When with 264 cams, the exhaust note is no longer a smooth note but in bass pulse.
Compare to my own S13 CA18, the only different between our cars, included HKS 256 8.8mm In/Ex cams on factory cam pulley, mine is full 3" turbo back included the dump pipe flange, 70mm intercooler cold pipe, other than that, everything power related is the same.
On the road test at 0.9 bar boost controller off, the turbo spool up compare to factory cams, only a little delay on spool, and the delay is acceptable, lost some torque on the low end due to boost come a little later, but after 3,500 rpm the torque come stronger, and last longer.
Compare the spool and torque to my own S13, the different is too small to tell.