Jump to content


Photo

Camshaft Identification


  • Please log in to reply
1 reply to this topic

#1 ACDodd

ACDodd

    Camshaft & Stage Two Head

  • Mini Docs
  • PipPipPipPipPipPipPipPip
  • 1,853 posts

Posted 13 October 2013 - 08:31 AM

The figures are based on OE spec where possible and where not they are based on my personal average obsevations when checking many of the same type of cam. Of course the info is correct (to the best of my knowledge) at the time of writing and I may change the info when I have confirmed new or updated info.

 

Here is a (very bad) image of the mule 998 motor I use for cam checking;

deebeec9.jpg

 

 

This image shows the oil pump slot drive which is common to all A+ cams. All the standard cams listed below are the A+ slot drive type, with 1/2" wide lobes.

CamIds003.jpg

 

 

This is the OE 848 A+/early 8.3:1 Low CR 998 A+ cam. It has 2 x 1/8" raised rings between lobes 3 & 4.

CamIds005.jpg

 

Checking height:   0.015" @ lobe

 

Timing:  (Intake): 5/45  (Exhaust):  40/10

 

Nominal lobe lift:  (Intake): 0.235"   (Exhaust): 0.235"

 

Duration  (Intake):  230    (Exhaust):    230

 

Lobe centre angle (Intake): 110    (Exhaust): 105 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.025"

 

Accuracy:  Very Good

 

 

 

 

This is the OE A+998 Cam (9.6:1/10.3:1 CR), It is also used in economy versions of the metro 1275, such as HLE and LE models, identified by the 1/8" raised ring between lobes 5 & 6.

CamIds001.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 9/41  (Exhaust):  49/11

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.249"

 

Duration  (Intake):  230    (Exhaust):    240

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.031"

 

Accuracy:  Very Good

 

 

 

 

Shown Below is the OE 1275 A+ sprite/injection(50hp) cam.

It has 2 x 1/8" raised rings between lobes 7 & 8.

CamIds002.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 9/41  (Exhaust):  44/6

 

Nominal lobe lift:  (Intake): 0.235"   (Exhaust): 0.235"

 

Duration  (Intake):  230    (Exhaust):    230

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.025"

 

Accuracy:  Very Good

 

 

 

 

The standard A+ 1275 cam as fitted to normal non-economy non performance engines is unmarked.

cf0c870c.jpg

 

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 9/41  (Exhaust):  55/17

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.263"

 

Duration  (Intake):  230    (Exhaust):    252

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.040"

 

Accuracy:  Very Good

 

Below is the SPI Copper cam as fitted to all injection coopers (63hp) Interestingly it has the same profile as the standard 1275 A+ above. It has 3 x 1/8" raised rings between lobes 7 & 8. 

2ff4d3c8.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 9/41  (Exhaust):  55/17

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.263"

 

Duration  (Intake):  230    (Exhaust):    252

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.040"

 

Accuracy:  Very Good

 

 

 

This is the MPI cam as found in all factory MPI's. It has no ID marks as the other cams, but is identified by the lack of distributer drive gear (is actually machined off), and it has a lobe (where the fuel pump accentric was on all other A-series engines) to enable the ECU to sense its position.

Cam006.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 14/46  (Exhaust):  55/17

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.263"

 

Duration  (Intake):  240    (Exhaust):    252

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.040"

 

Accuracy:  Very Good

 

 

A new addition, this is a rare item. It an A+ version of the old 2A948 profile. I have only ever seen these on some early MG metros, and as a result I do not know if this was ever a truly standard fit in an A+ engine. It is identified by having 3 x 1/8" rings between lobes 3 & 4.

cams002.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 20/52  (Exhaust):  56/18

 

Nominal lobe lift:  (Intake): 0.265"   (Exhaust): 0.265"

 

Duration  (Intake):  252   (Exhaust):    252

 

Lobe centre angle (Intake): 106    (Exhaust): 109 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.048"

 

Accuracy:  Very Good

 

 

 

This is the MG Metro cam, as fitted to MK2 metro VDP's, RSP Mini coopers, Metro Gta'a and 1275 Metro Sports.

It Has a 1/4" groove machined into the cam after the number one lobe. (piccy shows a reprofiled MG cam, with the same marking)

CamIds004.jpg

 

Checking height:   0.017" @ lobe

 

Timing:  (Intake): 16/56  (Exhaust):  59/29

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.263"

 

Duration  (Intake):  252    (Exhaust):    268

 

Lobe centre angle (Intake): 110    (Exhaust): 105 

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.054"

 

Accuracy:  Very Good

 

 

 

 

Below is an image showing the fairly typical wear pattern that I find on strip down of a road engine equipped with 1.5:1 ratio rockers. Typically mileages from 10,000 to 50,000 depending on use and oil changes etc.

This cam used to be OE SPI cooper.

 

b1769d16.jpg

 

Here is another pic of a worn cam, this cam from a 18,000 mile MPI with a typical 90hp kit fitted. It shows an intake lobe;

Cam010.jpg

 

This shot shows what it should look like;

Cam007.jpg

 

This is another lobe from the same cam, this time an exhaust lobe;

Cam009.jpg

 

 

 

 

 

 

Ok lets move on to the Aftermarket cams,

 

First off is the excellent Swiftune SW5 road cam, these figures are based on my observations based on 2 new examples I measured about 2 years ago. The figures are to be read as average of the 2,

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 16/48  (Exhaust):  52/12

 

Nominal lobe lift:  (Intake): 0.281"   (Exhaust): 0.281"

 

Duration  (Intake):  244    (Exhaust):    244

 

Lobe centre angle (Intake): 106    (Exhaust): 110 

 

Lobe separation angle:  108

 

Lift on overlap:   0.036"

 

Accuracy:  Good

 

 

Ok at last the SW5-07 

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 15/47  (Exhaust):  52/10

 

Nominal lobe lift:  (Intake): 0.286"   (Exhaust): 0.286"

 

Duration  (Intake):  242    (Exhaust):    242

 

Lobe centre angle (Intake): 106    (Exhaust): 111 

 

Lobe separation angle:  108.5

 

Lift on overlap:   0.0385"

 

Accuracy:  Exceptionally Good

 

 

The next in the Swiftune family is the SW10, which is basically a real hot road cam like a 286 but with better emissions and suited to road use where wear characteristics are more important than outright performance.

 

b]Checking height:[/b]   0.016" @ lobe

 

Timing:  (Intake): 34/66  (Exhaust):  70/30

 

Nominal lobe lift:  (Intake): 0.291"   (Exhaust): 0.291"

 

Duration  (Intake):  280    (Exhaust):    280

 

Lobe centre angle (Intake): 106    (Exhaust): 110 

 

Lobe separation angle:  108

 

Lift on overlap:   0.070"

 

Accuracy:  Good

 

 

Next is the much under used Kent 246 a nice all round road cam that has a little more bite than the SW5, these figures are based on kents own specs, plus with my own additions looking at 1 cam.

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 18/54  (Exhaust):  54/18

 

Nominal lobe lift:  (Intake): 0.285"   (Exhaust): 0.285"

 

Duration  (Intake):  252    (Exhaust):    252

 

Lobe centre angle (Intake): 108    (Exhaust): 108 

 

Lobe separation angle:  108

 

Lift on overlap:   0.048"

 

Accuracy:  Good

 

 

 

Next is the Kent 266 a nice all round road cam, these figures are based on kents own specs, plus with my own additions.

 

Checking height:   0.01225" @ lobe

 

Timing:  (Intake): 24/56  (Exhaust):  61/29

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.268"

 

Duration  (Intake):  260    (Exhaust):    270

 

Lobe centre angle (Intake): 106    (Exhaust): 106 

 

Lobe separation angle:  106

 

Lift on overlap:   0.054"

 

Accuracy:  Average

 

 

 

Here is the Kent 276;

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 29/61  (Exhaust):  66/34

 

Nominal lobe lift:  (Intake): 0.293"   (Exhaust): 0.315"

 

Duration  (Intake):  270    (Exhaust):    280

 

Lobe centre angle (Intake): 106    (Exhaust): 106 

 

Lobe separation angle:  106

 

Lift on overlap:   0.078"

 

Accuracy:  Below Average

 

 

 

Here is the 286;

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 34/66  (Exhaust):  71/39

 

Nominal lobe lift:  (Intake): 0.315"   (Exhaust): 0.324"

 

Duration  (Intake):  280    (Exhaust):    290

 

Lobe centre angle (Intake): 106    (Exhaust): 106 

 

Lobe separation angle:  106

 

Lift on overlap:   0.088"

 

Accuracy:  Below Average

 

 

 

Here is the new Billet 286;

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 34/66  (Exhaust):  71/39

 

Nominal lobe lift:  (Intake): 0.315"   (Exhaust): 0.324"

 

Duration  (Intake):  280    (Exhaust):    290

 

Lobe centre angle (Intake): 106    (Exhaust): 106 

 

Lobe separation angle:  106

 

Lift on overlap:   0.090"

 

Accuracy:  Good (much better than the older regrind)

 

 

 

The Kent 296;

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 39/71  (Exhaust):  76/44

 

Nominal lobe lift:  (Intake): 0.324"   (Exhaust): 0.340"

 

Duration  (Intake):  290    (Exhaust):    300

 

Lobe centre angle (Intake): 106    (Exhaust): 106 

 

Lobe separation angle:  106

 

Lift on overlap:   0.112"

 

Accuracy:  Average

 

 

 

Kents Version of the good old 649;

 

Checking height:   0.0125" @ lobe

 

Timing:  (Intake): 43/64  (Exhaust):  61/40

 

Nominal lobe lift:  (Intake): 0.323"   (Exhaust): 0.323"

 

Duration  (Intake):  287    (Exhaust):    281

 

Lobe centre angle (Intake): 100.5    (Exhaust): 100.5 

 

Lobe separation angle:  100.5

 

Lift on overlap:   0.110"

 

Accuracy:  Average

 

 

Piper's BP255. These figures are based soley on 1 pair of lobes checked in my jig.

 

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 12/48  (Exhaust):  44/16

 

Nominal lobe lift:  (Intake): 0.287"   (Exhaust): 0.285"

 

Duration  (Intake):  240    (Exhaust):    240

 

Lobe centre angle (Intake): 108    (Exhaust): 104

 

Lobe separation angle:  106

 

Lift on overlap:   0.045"

 

Accuracy:  Average

 

 

 

 

 

 

Piper's HR285. These figures are based soley on 1 pair of lobes checked in my jig.

 

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 28/64  (Exhaust):  60/32

 

Nominal lobe lift:  (Intake): 0.320"   (Exhaust): 0.320"

 

Duration  (Intake):  272    (Exhaust):    272

 

Lobe centre angle (Intake): 108    (Exhaust): 104 

 

Lobe separation angle:  106

 

Lift on overlap:   0.080"

 

Accuracy:  Not known

 

 

 

Piper's BP300. These figures are based soley on the avergae of 3 cylinders checked in my jig.

 

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 47/75  (Exhaust):  75/47

 

Nominal lobe lift:  (Intake): 0.315"   (Exhaust): 0.315"

 

Duration  (Intake):  302    (Exhaust):    302

 

Lobe centre angle (Intake): 104    (Exhaust): 104 

 

Lobe separation angle:  104

 

Lift on overlap:   0.125"

 

Accuracy:  Good

 

 

 

The Morspeed phase 2 (Fast road) Based on 1 example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 20/54  (Exhaust):  54/20

 

Nominal lobe lift:  (Intake): 0.305"   (Exhaust): 0.298"

 

Duration  (Intake):  254    (Exhaust):    254

 

Lobe centre angle (Intake):  107   (Exhaust): 107 

 

Lobe separation angle:  107

 

Lift on overlap:   0.048"

 

Accuracy:  Good

 

 

The Morspeed phase 3 (trackday cam) Based on 1 example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 28/62  (Exhaust):  62/28

 

Nominal lobe lift:  (Intake): 0.315"   (Exhaust): 0.311"

 

Duration  (Intake):  270    (Exhaust):    270

 

Lobe centre angle (Intake):  107   (Exhaust): 107

 

Lobe separation angle:  107

 

Lift on overlap:   0.065"

 

Accuracy:  Good

 

 

The Morspeed SL12 (Ultimate trackday cam) Based on 1 example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 36/66  (Exhaust):  81/43

 

Nominal lobe lift:  (Intake): 0.317"   (Exhaust): 0.328"

 

Duration  (Intake):  282    (Exhaust):    304

 

Lobe centre angle (Intake):  106   (Exhaust): 108

 

Lobe separation angle:  107

 

Lift on overlap:   0.105"

 

Accuracy:  Good

 

 

 

The Minispares Evolution 1 Based on 1 new example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 20/54  (Exhaust):  65/29

 

Nominal lobe lift:  (Intake): 0.263"   (Exhaust): 0.285"

 

Duration  (Intake):  254    (Exhaust):    274

 

Lobe centre angle (Intake):  106   (Exhaust): 109

 

Lobe separation angle:  107.5

 

Lift on overlap:   0.054"

 

Accuracy:  Good

 

 

 

 

 

Keith Calvers (not his own I know) , RE13 Based on 1 example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 34.5/61.5  (Exhaust):  63.5/32.5

 

Nominal lobe lift:  (Intake): 0.290"   (Exhaust): 0.290"

 

Duration  (Intake):  276    (Exhaust):    276

 

Lobe centre angle (Intake):  103.5   (Exhaust): 105.5 

 

Lobe separation angle:  104.5

 

Lift on overlap:   0.085"

 

Accuracy:  Good

 

 

 

Avonbar PH2 turbo cam, Based on 1 example only figures quoted at split overlap;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 15/47  (Exhaust):  62/14

 

Nominal lobe lift:  (Intake): 0.289"   (Exhaust): 0.320"

 

Duration  (Intake):  242    (Exhaust):    256

 

Lobe centre angle (Intake):  111   (Exhaust): 109 

 

Lobe separation angle:  110

 

Lift on overlap:   0.048"

 

Accuracy:  Very Good

 

 

Ok, a little differnt this time, but a very good cam company none the less, this is a B646 from NEWMAN cams Based on 1 example only;

 

Checking height:   0.016" @ lobe

 

Timing:  (Intake): 14/58  (Exhaust):  51/21

 

Nominal lobe lift:  (Intake): 0.302"   (Exhaust): 0.298"

 

Duration  (Intake):  252    (Exhaust):    252

 

Lobe centre angle (Intake):  112   (Exhaust): 105 

 

Lobe separation angle:  108.5

 

Lift on overlap:   0.047"

 

Accuracy:  Good


Edited by ACDodd, 13 October 2013 - 02:57 PM.


#2 ACDodd

ACDodd

    Camshaft & Stage Two Head

  • Mini Docs
  • PipPipPipPipPipPipPipPip
  • 1,853 posts

Posted 13 October 2013 - 03:01 PM

Here you go, I updated the size of some of the images. Happy to add to these figures if you have cams I can measure.

AC






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

Mini Spares