Thread: Franklin S4 centreline

I have it as 196nm according to wiki. Either way its far off 500

convert the power to hps for us.

did you have n1's before ? if so did you get gains going with franklins ?

stratton.

210hp. He also posted in another thread that he hasn't ever had any other cams, so no comparo with the Franklins.


I'm not understanding the tq figure though, that means 398ft lbs.............unless I'm converting it wrong.

thats torque at the wheels is it not, don't you need to divide by FD ratio to convert back to approx engine torque?

Would it be final drive or total reduction? If anyone knows it's a VZR box and the run was in 3rd.

would be total reduction if run in 3rd. FD if run in 1:1 fourth

Can someone please clarify.

According to the above, the FS4 centerlines are 114 In and 100Ex. But then by going one tooth advance put's the intake at 114 + (20/2) = 124 deg, and retaring it 5-6 degrees (camshaft) then puts the centerline back at around 118In.

Exhaust goes from 100 to 116Ex. With LSA 117. That goes against what you guys are saying about LSA of around 107-ish being ideal.

Am I misinterpreting something here?

Advancing the intake (if it was 114 ATDC) one tooth is 20 crank degrees (not 20/2) would move it to 94 then minus 5-6 ends up at 99-100. Exhaust from 100 BTDC plus 6 is 106. To get lobe separation angle you add them together and divide by 2 gives 102.5 or 103 LSA. This is SR20Turbofreaks degree settings, not the 107 LSA specd by 5speed.

Cool thanks for clarifying that. I always thought intake is specified at how many degrees before tdc it closes. Am I right in saying the above says the intake should open around 100 deg after tdc? I.e. Advancing intake makes it open sooner after the compression stroke?

What degrees intake and exhaust did you dial your setup to moles? I'm fitting my cam gears in the morning and would like the best possible starting point. Aiming for peak power at around 7.6k-8k that would hold till 9k.

No problem. We are talking about centrelines above or halfway between 2 levels of lift. Nissan apparently measures their lift at 0.4mm so you measure the timing angle at 0.4 from open and 0.4mm from closed and split it to get your centreline. If you are installing Franklin cams I wouldn't recommend installing them without measuring the centrelines to see where you're at as they seem to vary a lot. I only have FS4 on my intake high but I set it to ~105.5 and the exhaust high (N1) to 108 which gives LSA~107. Remember you have to click the latch in to engage the high cam lobe to measure them.