M30 camshaft identify and choice

J

jc971

Well-Known Member
Messages
102
Reaction score
26
Location
Guadeloupe 971
Hello
I will redo the cylinder head of my M30B35 so I take this opportunity to learn about the camshafts and maybe change it
I will use the parts I already have
I plan to reassemble the original delco ignition of the csi
I have 2 options :

my first option is an early 1250057.1 référence camshaft with a "3" at the end and the tip to activate the delco
according to my research this camshaft is a 272 degrees ??
ACC8F9AC-4784-498D-ADAE-A17EB6A6E708.jpeg
79690133-C1FE-4B1B-ABB9-569203032547.jpeg
386E0A85-8AFF-45AD-8E9E-D3E22ADF30D0.jpeg


but I also have a latter camshaft which does not have the tip to activate the delco and which has a "K" at the end,
it is the original one of the M30B35 it is a 264 degrees
on which I can mount the adapter for delco from irland engeenering

FAA95747-881E-45FF-AF98-DF6A2782E3B0.jpeg

IMG_9395.PNG


I compared them and the cams of the 264 are higher than those of the 272

on the left is the "K" camshaft 264 degrees
on the right is the "3" camshaft 272 degrees ??


E87DA729-F0F5-4329-BE2A-49AD91523C11.jpeg


can you confirm my early camshaft is a 272 degrees ?
is it normal that the camshaft with the highest degree has lower cams ?
what is the best option for me ?
put the code "3" camshaft
or the "K" cam with the adaptator nut for early to late from irland engineering ?

I quote :

"Identifying Stamp

I believe the camshafts all have the same part number, but the grind is identified by a number stamped on the back end or the camshaft. This is edited from a previous discussion:

Remove the Cover on the backside of the head and look at the number that is stamped on the cam.

1 = 260° (2500) lift 6.8471mm (8.9mm at valve)

2 = 264° (early 2800) lift 7.4228mm (9.7mm at valve)

3 = 272° (late 2800 and all 3.0) lift 7.4228mm (9.7mm at valve)

For comparison, the milder Schrick grind has 282º duration and lift of 8.4/10.9mm. There are differences in the lift figures quoted on the various websites, but these are based on a 1.3 rocker arm ratio. "
 
Most people who go with a b35 use the Schrick cam but the stock cam is fine as well. Only the duration is different between the 264 and 272, same lift. But saying you are keeping the original Delco ignition is confusing. The original is not Delco, and I hope you aren’t planning on using the CSi ecu. I would be concerned that it won’t know what your motor is doing, it is a fairly crude computer. With a b35 ecu you can’t use the original ignition but you can use that cam nut adapter and remove the guts from from your distributor and have it staked so there is no longer any mechanical advance. You need the correct upper timing cover and valve cover as the center mounting bolt moved ever so slightly and won’t match all valve covers. Hope I didn’t misunderstand what your objective is.
 
Chris, i think he is going with triple webers ... i got lost with the Delco ignition as well. i am curious how the timing, etc gets sorted unless there is an ECU or a return to a traditional dizzy
 
The K cam is low duration and low lift. It is for a family sedan.
Do the right thing and install the Shrick.
 
I'm going to install triple weber and put the original igniter of the 3.0csi, or maybe an E24 igniter with ignition module but that another subject
I have the original upper timing cover and valve cover who is well
honestly i don't want to spend another $ 400 on a shrick camshaft..
 
i think i will use the camshaft nut adaptator..
since my camshaft 3 is note better than the original b35
 
Jc971-

Would you like me to help you? I can see that we have done a poor job in explaining the different cams.

A 272 DEGREE cam holds the valve open longer than a 264 DEGREE cam.
The longer duration or degree that the valve is open, the more performance you get.

A high lift cam allows the valve to open further, allowing more performance.


The lift of a cam has nothing to do with duration.

Hope this helps....



Camshaft Duration

help.summitracing.com help.summitracing.com
 
Last edited:
I had my cam reground by Schneider Cams in San Diego to 284 specs. Cost was $125 I haven't driven the car yet but I am pleased at how it runs at idle and minor free revving. If I am not mistaken, they do Frank Fahey's cams and are pretty up to speed on M30 cams. It's worth a phone call and talking with Jerry who was my contact at the time i had mine done
 
Weber carbs like bigger lobe separation angles , less overlap.
Of course highest lift what is possible.
 
hello guys

thanks for your informations

I understand quite well how a camshaft works

I wanted to know if my code "3" camshaft was really a 272 degrees
I had the doubt because the cams are lower, but not necessarily wider, so this camshaft seems less efficient to me than the original one,
so I ordered the camshaft nut adaptator for late to early and I will put my M30b35 in my car, with my triple weber dcoe, it will be enough to run my 3.0csi

I would like to make a "3500cs" logo for the rear trunk
 
i cannot answer your question, i only know what is in the orange book - 4 camshafts
11311251840 - only used for 2.5cs / csa
11311254979 - used in all coupes (euro + usa)
11311255984 - 300 degree cam used in euro cars (not in usa)
11311255985 - 324 degree cam used in euro cars (not in usa)

the latter two have a notation ' sonderausstattung fur wettbewerbsfahrzeuge' which i presume was for racing coupes

cams in other m30 engines?
 
You must log in or register to reply here.
Back
Top