Well doing some research I found out that the Cams are different in the
1991 engine from the 1992 and 1993 engine. What I would like to know
from someone with a 1991 FSM and a 1992 or 1993 FSM what the actual
difference is. No electronic FSM’s please because who knows if they are a
1991, 1992, 1993, or 1994. They are all the same except for the cam page.
The information can be found on page EM-52 looking Valve Timing Section “a” and “b”
-Thanks
1993:
A 240
B 248
it was EM-47 for me
I think the 91 has a 248/248. I can also tell you there is no noticeable difference. The 91 has a slightly more open top end… but for example, a 92 in better shape will have more power. If you are thinking of swapping… not worth the trouble imo.
I don’t think any year had 248/248, the only way to get this is to repin the exhaust cam off of a 91.
I thought 91 cams were 240/248, and all other dohc cams were 232/232
My understanding is that all s14 KA’s were 232/232.
I’m not 100% but I think that all 91-93 KA’s are 240/248
Someone please clear this up
Well I know forsure all S14 Cams were 232/232
And I know forsure that all S13 1992 - 1994 cams were 240/248
But rumor has it that 1991 cams are differnt, both of them.
I need this info from someone who has a 1991 FSM?
ANYONE?
Missin that page 
EDIT
i do not think the duration is any different it is the lift of the exhaust cam that does it 
I though the lift on all DOHC motors was 42 but I could be mistaken.
Well Philip if thats what it states then thats what it must be.
So to clear things up all S13 Cams are 240/248 w/ 42mm Lift?
I don’t see why they would be different for 1991 compared to the rest of the s13 years. Rumors are rumors and to me have no point until PROVEN correct, and Phil’s FSM just reassures that they are the same. Unless of course you have a spare '91 cam around and are so inclined to measure the duration.