Request for PW3 specification

Does anyone have PW3 camshaft information, spec sheet, excel data, valve clearance etc that could be posted please?

Also, the peterwilliamsracing website I used to look at several years ago seems to have been transformed into a sales website for a very expensive custom bike. I was looking for a pdf document where he talks about the PW3 camshaft and design aims, but I can't see that any more, does anyone have a copy of that perhaps

Peter

In. opens 50deg BTDC and closes 82deg ABDC. Ex. opens 84deg BBDC and closes 48deg ATDC - measured at the valve. In. valve lift @ TDC 0.145" measured at pushrod zero valve clearance. Tappet clearance In. and Ex. 0.011".

Thanks for that.
When you say "...measured at valve" does that assume you have set a .011" valve clearance, and are measuring the point at which the valve starts to open? But, for example is that when the follower is on the ramp, or after the ramp?
The reason I am looking for more specs, profile data is to try and understand more.

http://atlanticgreen.com/camsurvey.htm
http://atlanticgreen.com/images/cam940.gif

http://www.nortonownersclub.org/support ... /camshafts

I got the info off an installation sheet supplied by Mick Hemmings and it dosen't specify what valve clearance but I'm assuming it would be 0.011" which allows for the ramp. A while ago I asked Peter Williams why different cams required different valve clearances . He told me it's a combination of the cam ramp and the rocker arm ratio. PW3 cams have a ramp of 0.010" and a Commando's rocker ratio is 1.13:1, multiply the two together and you get 0.011", or there abouts so it will be after the ramp and the actual start of the valve timing as designed into the cam.

Al-otment said:

I got the info off an installation sheet supplied by Mick Hemmings and it dosen't specify what valve clearance but I'm assuming it would be 0.011" which allows for the ramp. A while ago I asked Peter Williams why different cams required different valve clearances . He told me it's a combination of the cam ramp and the rocker arm ratio. PW3 cams have a ramp of 0.010" and a Commando's rocker ratio is 1.13:1, multiply the two together and you get 0.011", or there abouts so it will be after the ramp and the actual start of the valve timing as designed into the cam.

Click to expand...

That all sounds very logical thank you!

If you want to check the timing at the valve, to get the 0.145" as measured at the pushrod, set the valve clearance to zero & multiply 0.145" by the rocker ratio of 1.13:1. This will be 0.164".
Hope this makes sense.
Martyn.

Thanks, what I would really like is the data for the cam, maybe someone has degreed it already and has the data? To be precise, data that will allow me to plot the lift wrt the rotation. There appears to be lots of pictures of the curves (as per links in LABS posts), but no data......

Measured at cam.

0 0.0000 0.0000
2 0.0000 -0.0000
4 0.0000 -0.0000
6 0.0000 -0.0000
8 0.0000 -0.0000
10 0.0000 -0.0001
12 0.0000 -0.0001
14 0.0000 -0.0001
16 0.0000 -0.0001
18 0.0000 -0.0001
20 0.0000 -0.0001
22 0.0000 -0.0001
24 0.0000 -0.0001
26 0.0000 -0.0001
28 0.0000 -0.0001
30 0.0000 -0.0001
32 0.0000 -0.0001
34 0.0000 -0.0001
36 0.0000 -0.0001
38 0.0000 -0.0001
40 0.0000 -0.0001
42 0.0000 -0.0002
44 0.0000 -0.0002
46 0.0000 -0.0002
48 0.0000 -0.0002
50 0.0000 -0.0002
52 0.0000 -0.0002
54 0.0000 -0.0003
56 0.0000 -0.0002
58 0.0000 0.0000
60 0.0000 0.0004
62 0.0000 0.0008
64 0.0000 0.0014
66 0.0000 0.0019
68 0.0000 0.0024
70 0.0000 0.0030
72 0.0000 0.0036
74 0.0000 0.0041
76 0.0000 0.0046
78 0.0000 0.0052
80 0.0000 0.0057
82 0.0000 0.0061
84 0.0000 0.0065
86 0.0000 0.0069
88 0.0000 0.0074
90 0.0000 0.0079
92 0.0000 0.0085
94 0.0000 0.0093
96 0.0000 0.0101
98 0.0000 0.0113
100 0.0000 0.0128
102 0.0000 0.0146
104 0.0000 0.0169
106 0.0000 0.0194
108 0.0000 0.0224
110 0.0000 0.0259
112 0.0000 0.0300
114 0.0000 0.0343
116 0.0000 0.0391
118 0.0000 0.0445
120 0.0000 0.0500
122 -0.0000 0.0560
124 -0.0000 0.0625
126 -0.0000 0.0691
128 -0.0000 0.0759
130 -0.0000 0.0831
132 -0.0000 0.0904
134 -0.0000 0.0976
136 -0.0000 0.1054
138 -0.0001 0.1130
140 -0.0001 0.1203
142 -0.0001 0.1279
144 -0.0001 0.1356
146 -0.0001 0.1430
148 -0.0001 0.1505
150 -0.0001 0.1581
152 -0.0001 0.1654
154 -0.0001 0.1725
156 -0.0001 0.1799
158 -0.0001 0.1872
160 -0.0001 0.1942
162 -0.0001 0.2014
164 -0.0001 0.2084
166 -0.0001 0.2151
168 -0.0001 0.2220
170 -0.0001 0.2289
172 -0.0001 0.2353
174 -0.0001 0.2419
176 -0.0001 0.2485
178 -0.0001 0.2546
180 -0.0001 0.2608
182 -0.0001 0.2672
184 -0.0001 0.2731
186 -0.0001 0.2788
188 -0.0001 0.2848
190 -0.0001 0.2903
192 -0.0001 0.2957
194 -0.0001 0.3011
196 -0.0001 0.3063
198 -0.0001 0.3112
200 -0.0001 0.3161
202 -0.0001 0.3209
204 -0.0001 0.3253
206 -0.0001 0.3298
208 -0.0001 0.3340
210 -0.0001 0.3381
212 -0.0001 0.3419
214 -0.0001 0.3457
216 -0.0001 0.3492
218 -0.0001 0.3525
220 -0.0001 0.3557
222 -0.0001 0.3586
224 -0.0001 0.3613
226 -0.0001 0.3640
228 -0.0001 0.3663
230 -0.0001 0.3685
232 -0.0001 0.3706
234 -0.0001 0.3724
236 -0.0001 0.3740
238 -0.0001 0.3754
240 -0.0001 0.3767
242 -0.0001 0.3776
244 -0.0001 0.3785
246 -0.0001 0.3791
248 -0.0001 0.3795
250 -0.0001 0.3797
252 -0.0001 0.3798
254 -0.0001 0.3796
256 -0.0001 0.3793
258 -0.0001 0.3787
260 -0.0001 0.3779
262 -0.0001 0.3769
264 -0.0001 0.3757
266 -0.0002 0.3744
268 -0.0002 0.3728
270 0.0000 0.3710
272 0.0004 0.3690
274 0.0008 0.3668
276 0.0014 0.3645
278 0.0019 0.3619
280 0.0025 0.3591
282 0.0030 0.3563
284 0.0036 0.3532
286 0.0041 0.3498
288 0.0047 0.3464
290 0.0052 0.3426
292 0.0057 0.3386
294 0.0061 0.3347
296 0.0066 0.3306
298 0.0070 0.3261
300 0.0075 0.3216
302 0.0080 0.3169
304 0.0086 0.3119
306 0.0093 0.3069
308 0.0102 0.3019
310 0.0114 0.2964
312 0.0129 0.2910
314 0.0146 0.2856
316 0.0169 0.2797
318 0.0196 0.2737
320 0.0226 0.2679
322 0.0259 0.2618
324 0.0298 0.2555
326 0.0341 0.2493
328 0.0389 0.2429
330 0.0443 0.2361
332 0.0498 0.2296
334 0.0558 0.2229
336 0.0622 0.2160
338 0.0689 0.2092
340 0.0758 0.2024
342 0.0830 0.1952
344 0.0904 0.1880
346 0.0976 0.1811
348 0.1051 0.1737
350 0.1128 0.1663
352 0.1202 0.1591
354 0.1277 0.1517
356 0.1356 0.1440
358 0.1429 0.1366
360 0.1503 0.1293
362 0.1581 0.1213
364 0.1653 0.1139
366 0.1725 0.1066
368 0.1800 0.0989
370 0.1872 0.0916
372 0.1942 0.0844
374 0.2014 0.0771
376 0.2084 0.0702
378 0.2151 0.0637
380 0.2220 0.0572
382 0.2289 0.0511
384 0.2354 0.0456
386 0.2419 0.0402
388 0.2485 0.0353
390 0.2548 0.0309
392 0.2609 0.0269
394 0.2672 0.0233
396 0.2733 0.0202
398 0.2790 0.0176
400 0.2848 0.0153
402 0.2905 0.0134
404 0.2959 0.0119
406 0.3013 0.0106
408 0.3065 0.0097
410 0.3115 0.0089
412 0.3164 0.0083
414 0.3212 0.0078
416 0.3257 0.0074
418 0.3300 0.0069
420 0.3345 0.0065
422 0.3384 0.0060
424 0.3423 0.0057
426 0.3461 0.0051
428 0.3496 0.0046
430 0.3530 0.0041
432 0.3562 0.0035
434 0.3592 0.0029
436 0.3619 0.0023
438 0.3645 0.0019
440 0.3670 0.0014
442 0.3692 0.0009
444 0.3712 0.0004
446 0.3731 0.0003
448 0.3747 0.0002
450 0.3761 0.0002
452 0.3774 0.0002
454 0.3784 0.0002
456 0.3792 0.0002
458 0.3799 0.0002
460 0.3803 0.0002
462 0.3805 0.0002
464 0.3805 0.0002
466 0.3804 0.0002
468 0.3801 0.0002
470 0.3795 0.0002
472 0.3787 0.0002
474 0.3778 0.0002
476 0.3765 0.0002
478 0.3751 0.0002
480 0.3737 0.0002
482 0.3720 0.0002
484 0.3699 0.0002
486 0.3678 0.0002
488 0.3656 0.0002
490 0.3629 0.0002
492 0.3602 0.0002
494 0.3574 0.0002
496 0.3543 0.0002
498 0.3510 0.0002
500 0.3477 0.0002
502 0.3440 0.0002
504 0.3402 0.0002
506 0.3363 0.0002
508 0.3322 0.0002
510 0.3278 0.0002
512 0.3234 0.0002
514 0.3189 0.0002
516 0.3139 0.0002
518 0.3090 0.0002
520 0.3040 0.0002
522 0.2986 0.0002
524 0.2932 0.0002
526 0.2878 0.0002
528 0.2822 0.0002
530 0.2763 0.0002
532 0.2705 0.0002
534 0.2644 0.0003
536 0.2582 0.0003
538 0.2519 0.0003
540 0.2456 0.0003
542 0.2389 0.0003
544 0.2324 0.0003
546 0.2259 0.0003
548 0.2189 0.0003
550 0.2121 0.0003
552 0.2053 0.0003
554 0.1981 0.0003
556 0.1910 0.0003
558 0.1840 0.0003
560 0.1767 0.0003
562 0.1693 0.0003
564 0.1620 0.0003
566 0.1546 0.0003
568 0.1471 0.0003
570 0.1397 0.0003
572 0.1322 0.0003
574 0.1245 0.0003
576 0.1169 0.0003
578 0.1094 0.0003
580 0.1019 0.0003
582 0.0943 0.0003
584 0.0870 0.0003
586 0.0798 0.0003
588 0.0725 0.0003
590 0.0658 0.0002
592 0.0599 0.0002
594 0.0545 0.0002
596 0.0488 0.0002
598 0.0441 0.0002
600 0.0393 0.0002
602 0.0348 0.0002
604 0.0304 0.0002
606 0.0260 0.0002
608 0.0218 0.0002
610 0.0180 0.0002
612 0.0157 0.0002
614 0.0137 0.0002
616 0.0121 0.0002
618 0.0109 0.0002
620 0.0099 0.0002
622 0.0091 0.0002
624 0.0085 0.0002
626 0.0080 0.0002
628 0.0076 0.0002
630 0.0071 0.0002
632 0.0067 0.0002
634 0.0063 0.0002
636 0.0057 0.0002
638 0.0052 0.0002
640 0.0047 0.0002
642 0.0041 0.0002
644 0.0036 0.0002
646 0.0029 0.0002
648 0.0024 0.0002
650 0.0019 0.0002
652 0.0014 0.0002
654 0.0009 0.0002
656 0.0004 0.0002
658 0.0003 0.0002
660 0.0003 0.0002
662 0.0002 0.0002
664 0.0002 0.0002
666 0.0001 0.0002
668 0.0001 0.0002
670 0.0001 0.0002
672 0.0001 0.0002
674 0.0000 0.0002
676 0.0000 0.0002
678 0.0000 0.0002
680 0.0000 0.0001
682 0.0000 0.0001
684 0.0000 0.0001
686 0.0000 0.0001
688 0.0000 0.0000
690 0.0000 0.0000
692 0.0000 0.0000
694 0.0000 0.0000
696 0.0000 0.0000
698 0.0000 0.0000
700 0.0000 0.0000
702 0.0000 0.0000
704 0.0000 0.0000
706 0.0000 0.0000
708 0.0000 0.0000
710 0.0000 0.0000
712 0.0000 0.0000
714 0.0000 0.0000
716 -0.0000 0.0000
718 -0.0000 0.0000

Old_Bloke said:

Thanks, what I would really like is the data for the cam, maybe someone has degreed it already and has the data? To be precise, data that will allow me to plot the lift wrt the rotation. There appears to be lots of pictures of the curves (as per links in LABS posts), but no data......

Click to expand...

Comnoz
That's absolutely great. Many thanks

Peter

Jim, your figures for the PW3 cam show a peak lift on one lobe at 252 degrees, while the other is at 462/4 degrees (call it 463) This indicates a lobe separation based on the point of maximum lift of 100.5 degrees. If this is the case, I would say you have a very rare PW3. Most would seem to have been measured at around 106 degrees, while I have measured one at over 109 degrees.

Perhaps I'm interpreting your data incorrectly, in which case I would welcome your own explanation of the lobe separation for the camshaft you measured.

If the lobe separation IS 100.5 degrees, this is a camshaft Jim Schmidt would surely have given his eye teeth to have gotten his hands on a few years back.

Snotzo said:

Jim, your figures for the PW3 cam show a peak lift on one lobe at 252 degrees, while the other is at 462/4 degrees (call it 463) This indicates a lobe separation based on the point of maximum lift of 100.5 degrees. If this is the case, I would say you have a very rare PW3. Most would seem to have been measured at around 106 degrees, while I have measured one at over 109 degrees.

Perhaps I'm interpreting your data incorrectly, in which case I would welcome your own explanation of the lobe separation for the camshaft you measured.

If the lobe separation IS 100.5 degrees, this is a camshaft Jim Schmidt would surely have given his eye teeth to have gotten his hands on a few years back.

Click to expand...

I really don't know if the PW3 I measured is representative of all of them or not. I have only measured one. It is the cam that Kenny supplied when I built his racebike engine.

I would not look for the points of maximum lift to try and figure the lobe centers. The right way to do it would be to look for the points at .150 inch [or any mid ltft figure] before and after peak lift and split the difference to find the peak. That will give you much better accuracy. Jim

Hi Jim,

I see that you stated "Measured at the cam" but can you say a little bit about how you measured at the cam? Was it a stylus dial indicator on the lobe(s) or at the lifter.

Where I am going with this is different lifter radiuses will yield different lifter movements.

The graph above is based on Jim's cam profiling table of data above.

Dances with Shrapnel said:

Hi Jim,

I see that you stated "Measured at the cam" but can you say a little bit about how you measured at the cam? Was it a stylus dial indicator on the lobe(s) or at the lifter.

Where I am going with this is different lifter radiuses will yield different lifter movements.

Click to expand...

I have a jig that holds a lifter in position and a stepper motor drive that moves the cam 1 degree at a time. A sensor above the lifter sends the info to a computer that orders the steps and collects the data. I have an assortment of lifters with flat or several different radius grinds that fit in the jig. Jim

comnoz said:

I have a jig that holds a lifter in position and a stepper motor drive that moves the cam 1 degree at a time. A sensor above the lifter sends the info to a computer that orders the steps and collects the data. I have an assortment of lifters with flat or several different radius grinds that fit in the jig. Jim

Click to expand...

What a toy cupboard you have :shock:

comnoz said:

Dances with Shrapnel said:

Hi Jim,

I see that you stated "Measured at the cam" but can you say a little bit about how you measured at the cam? Was it a stylus dial indicator on the lobe(s) or at the lifter.

Where I am going with this is different lifter radiuses will yield different lifter movements.

Click to expand...

I have a jig that holds a lifter in position and a stepper motor drive that moves the cam 1 degree at a time. A sensor above the lifter sends the info to a computer that orders the steps and collects the data. I have an assortment of lifters with flat or several different radius grinds that fit in the jig. Jim

Click to expand...

Good stuff! What lifter was used to collect the data in the table above?

Dances with Shrapnel said:

comnoz said:

Dances with Shrapnel said:

Hi Jim,

I see that you stated "Measured at the cam" but can you say a little bit about how you measured at the cam? Was it a stylus dial indicator on the lobe(s) or at the lifter.

Where I am going with this is different lifter radiuses will yield different lifter movements.

Click to expand...

I have a jig that holds a lifter in position and a stepper motor drive that moves the cam 1 degree at a time. A sensor above the lifter sends the info to a computer that orders the steps and collects the data. I have an assortment of lifters with flat or several different radius grinds that fit in the jig. Jim

Click to expand...

Good stuff! What lifter was used to collect the data in the table above?

Click to expand...

Just stock flat Norton lifter. Jim

Jim
your method of determining the point of maximum lift does not differ over much from mine where a symmetrical cam form is concerned. Call it maximum lift or lobe center, a difference is found when measuring a non symmetrical profile such as a Porsche 911 cam or similar. I use Audie Technilogies Cam Pro Plus with the Standard preference for determining the point of maximum lift in which many measurements are taken around peak lift and the lifts are averaged taking the points measured at .003, .006 and .009 thou. before and after peak lift ( all other measurements are then discarded) .

The PW3 I measured recently had the pair of lobes differing in their centers by approx 0.5 degree, left cylinder to right. Using a similar measuring method to yours, I checked these cams out at 9, 8, 7, 6, 5, and 4mm lifts, and in each and every case the lobe separation was the same to the first decimal point at 109.2 degrees.
The Cam Pro Plus system recorded the lobe separation as 109.28 degrees.

The PW3 has near symmetrical profiles (or is intended to have) so my estimate from your peak lift points should not have been too far out. If you have the lobe centers recorded it would be interesting to compare with the cams I have measured.