Help with identifying re-profiled cam

[PaulB]

Hi can anyone help me to identify a re-profiled Sprint camshaft?

All I can measure is the base circle diameter which is 1.09inch and across the cam lobe which is 1.445inch. Give a lift of 0.355inch which is pretty close to the strandard cam. Its definitely re-profiled, you can see the difference when you compare it with a standard.

[soe8m]

It can be a std spec regrind cam what was worn or damaged.

Jeroen

[PaulB]

I thinkl it is probably an uprated cam. The shape cam lobe is quite different to a standard cam,

[trackerjack]

Has it got anything stamped on the end?
Holbay do mark but Newman dont, nor do they help with details.

[Mad Mart]

Newman do stamp there cams Jon, or is that just the billet ones?

[PaulB]

It is stamped 59 on the end, but I don't know the significance if any.

[soe8m]

The degrees to set? Do you have a picture of it?

Jeroen

[PaulB]

Here are two pictures of the re-profiled next to a standard camshaft.....

PIC_1622.JPG (481.89 KiB) Viewed 2532 times

PIC_1621.JPG (485.86 KiB) Viewed 2532 times

The re-profiled cam is on the left

[trackerjack]

Newman do stamp there cams Jon, or is that just the billet ones?

Thats interesting Mart, perhaps the one I used was made in haste and it got left off, and they never did let me know what nominal setting was a good start so if my dodgy memory is right I set it at 109 deg.
A rolling road will sort it properly though.

[PaulB]

Anyone???

[Jon Tilson]

IIRC STR91's and the TT equivalent are 106 ATDC inlet peak on no 1.

There is a chart on here somewhere....

Jonners

[Dolly-Nut]

http://www.triumphowners.com/uploaded/3 ... sprint.jpg

[TahitiSPRINT]

Hi Paul,

If the cam is of un-known origin and not marked, you have to measure the timing yourself with a dial test indicator (DTI) and with the cam mounted in a cylinder head.

You can test your measuring accuracy with the standard cam. The std cam should have a 18/58 – 58/18 timing (256 degrees duration).

With the newfound details on your re-profiled cam, you can compare with the list from the above link.

Have fun

[PaulB]

Thanks guys,

I am familiar with the chart, but can't see how it helps me identify the camshaft???

[soe8m]

Set the valve play as narrow as possible, about 0,05mm. Note the degrees in turning when the inlet valve starts opening and is closed. That is the duration. The lift you can calculate by the cam hight minus the base circle. The found figures you can compare with the tabel and then you know what cam you have.

Jeroen