I have 4 camshafts I've mixed up. The only noticeable markings are:

IN , R3
EX, R3

IN, R2
EX, R4

I'm certain one set is from an F20c. I'm not sure if the other pair is from an F20c or F22. Does anyone have the key to these markings?

 

my F20C2 cams say:
IN R1
EX R2

 

Thanks. Doesn't help But thanks.

 

On a photo of my '05 F20C2 head I saw an exhaust cam marked R1.

(just lucky to have this in the picture)




Why not measure the hight of the lobes to find the difference?

 

Well I read the "official cam thread" (https://www.s2ki.com/s2000/topic/635...mshaft-thread/ , but it doesn't give exacting measurements for both AP1 and AP2 cams. Additionally measuring for the lift of 12.15 mm listed for AP1 cams leaves me wondering if that is the same for both intake and exhaust lobes.

Lastly, there's a good chance these are all AP1 cams ( I wish I'd marked them all better, but I didn't). If that is the case, what might be the difference between them (if all AP1 theyd' have come from a MY '00 and a MY'01).

So I was hoping somebody came up with determination on markings rather than on properly measuring the difference of an extimated .15 mm on a lobe (I have calipers, but no other means myself to measure the entire profile).

 

Did you read all 21 pages of that thread?




Anyway.. the F20C2 total lobe hights (*) are in my MY'00-03 service manual.
Mentioned twice, in the design specs and in chapter-page 6-39.
(this you can find online, in pdf)
So if you can get your hands on a MY'05-09 (USDM AP2 with F22) service manual you will have both.
Doesn't give timing but if there is a difference in lobe hight that is all you need.
There must be people reading this with a F22 Helms that can help you.

(*) it shows the non-VTEC lobes are not the same in lift.
Most likely to create intake swirl at lower rpm.

 

I did read, well scan in the case of some of the pages, the entire thread yes. Much of it had to do with BC cams, or the mixed use of cams from F20 and F22. There is a difference in lobe height, but it wasn't huge. Measurable, but not huge. I know I can go that routed.

However the clear R markings must mean something and I'm not being lazy, I'm just trying to do the best job possible job of using this community's great depth of knowledge in identifying what I have and make the right choice.

 

For the F20 cams:
Total lobe hight, in mm.
Prim and Sec are non-VTEC lobes.
Pri is the first one, seen from the chain.
Mid is the VTEC lobe.
No service limit given.

Now all you need is someone with an F22 Helms (or known F22 cams) to post the F22 lobe hight.
Feel free to post your findings too


I'm sure the "R" markings mean something.
And I'm not calling you lazy

 

That does help. My other thought process here is that these may all be F20 cams. If that is the case, is there a difference with the R markings and what do they mean.

I want F20 cams, so that's really what I need to confirm.


It looks like we have no answers on the R markings, I was just hoping to find some.

 

Another set (IN and EX) of F20Cs cams I have areboth marked R1.
They are stored elsewhere and today I am elsewhere so I had a look at them

IOW: I'm pretty sure the only way to indentify cams is to measure.

I'm surpriced no one posted F22 cam lobe hights.
It's not one has to actually go out and measure, I mean, the specs are (must be.. right?) in a USDM MY'05 Helms?
Maybe its not enough.......