Cam Timing - PorKen the GENIUS
#31
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You can set it to -2°/0° with the 32V'r and call it good. (If the belt is new, you'll want to recheck at retension or 1K miles w/PKsn'r.)
The 20° called for when using the dial indicator isn't the actual advance, it's the motion of moving from 0|T to 2|0 that moves the cam far enough for the cam lobe 'lift' to register on the dial. S³, S4, GT, GTS cams have different amounts of lift at 20° compared to each other, so the dial indicator measurement is different in the specs. In degrees, however, they all measure -2°/0° with a 32V'r (cold engine).
The 20° called for when using the dial indicator isn't the actual advance, it's the motion of moving from 0|T to 2|0 that moves the cam far enough for the cam lobe 'lift' to register on the dial. S³, S4, GT, GTS cams have different amounts of lift at 20° compared to each other, so the dial indicator measurement is different in the specs. In degrees, however, they all measure -2°/0° with a 32V'r (cold engine).
Since I have it set now, I'll just proceed from here. Maybe I'll use the tool at belt check time. I'm not using a new belt, the one I had on when it failed only had about 13000 miles, or 2.5 years.
#32
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I didn't really understand what you were saying by wanting to "start at 0TDC rather than the 20", so I gave you the whole speel.
I'm in a bit of a fog today, I have to admit I also don't understand what you are saying here either, contrasting 'advance' versus the hot delta?
#33
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Correct me if I'm wrong, never having used your tool, but my understanding is that you set the crank at TDC, and move the cam hub accordingly. In contrast, the stupid book requires that one set the crank at 20 deg ATDC(intake stroke on 1 and 6), and the dial indicator for a plunge reading of 0.xxx inches depending on cam profile(S3, S4, GT/CS, etc). Then tighten the whole thing up, and go around twice, to recheck the plunge reading at 20ATDC.
The plunge readings on the left bank intake cam, and the right bank intake cam are theoretically exactly the same, because the crank throws from the first to the second journal are 90Deg. However, the expansion of the engine causes a greater belt run on the right bank, so the plunge reading is offset slightly to account for that. This will make the cams perfectly in sync during warm operation.
The plunge readings on the left bank intake cam, and the right bank intake cam are theoretically exactly the same, because the crank throws from the first to the second journal are 90Deg. However, the expansion of the engine causes a greater belt run on the right bank, so the plunge reading is offset slightly to account for that. This will make the cams perfectly in sync during warm operation.
#34
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I can't say enough good about the 32V'r. It saved my butt when I installed a new cam gear. In fact, I had purchased the first version of the 32V'r AND dial indicator setup from Harbor Freight figuring I might need that too. While I was waiting for the cam gear to be delivered, Ken came out with the updated 32V'r and I bought and used it instead (totally satisfied)
Therefore, I have the other unused tools FOR SALE:
32V'r (first version): It works just as well as the latest version except that the more recent rendition has an extra "notch" for a more flexible setting. Just as accurate as the 2nd version. Plus a jewel case! Plus the nifty alignment bar. I forgot what I paid for it and it's still brand new, unused. $40 plus $5 priority mail to continental USA only.
I also have, new in box, the Dial Indicator and Magnetic base with fine adjustment for checking the valve timing the "old fashioned way". Because of the 928 aluminum block, you'll need to make a bolt down piece for the base to attach to. Directions on this should be available by doing a search of Rennlist. I paid $39.97 and will sell for $18 plus $9.80 priority shipping in continental USA.
PM me if interested.
H2
Therefore, I have the other unused tools FOR SALE:
32V'r (first version): It works just as well as the latest version except that the more recent rendition has an extra "notch" for a more flexible setting. Just as accurate as the 2nd version. Plus a jewel case! Plus the nifty alignment bar. I forgot what I paid for it and it's still brand new, unused. $40 plus $5 priority mail to continental USA only.
I also have, new in box, the Dial Indicator and Magnetic base with fine adjustment for checking the valve timing the "old fashioned way". Because of the 928 aluminum block, you'll need to make a bolt down piece for the base to attach to. Directions on this should be available by doing a search of Rennlist. I paid $39.97 and will sell for $18 plus $9.80 priority shipping in continental USA.
PM me if interested.
H2
#35
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Correct me if I'm wrong, never having used your tool, but my understanding is that you set the crank at TDC, and move the cam hub accordingly.
However, the expansion of the engine causes a greater belt run on the right bank, so the plunge reading is offset slightly to account for that. This will make the cams perfectly in sync during warm operation.
However, the expansion of the engine causes a greater belt run on the right bank, so the plunge reading is offset slightly to account for that. This will make the cams perfectly in sync during warm operation.
The 32V'r has four keyways, so you can do a quick check of the timing at 4|5 and 0|T at both #1, and #6. Because of differing valve spring pressures at the different angles, which stretches the belt differently, and changes the degree reading slightly, the most accurate reading is at 0|T #1. I include a spacer which fits under the cam bolt washer, which when tightened, allows you to move the cam/hub with a wrench, independently of the sprocket.
The difference in plunge readings equates to 2° retard, as measured by the 32V'r, so I recommend these settings as measured by the tool, engine cold: ¼ -2°, ⅝ 0°.
#37
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Is it me or does it seem like I'm repeating myself repeating myself?
The WSM specs for all 928 32V cams equate to the following, measured with the 32V'r, with the engine cold.
cyls 1-4: 2° retard
cyls 5-8: 0°
For the best results (if you can stand the heat) to set both sides to 0°, with the engine hot/warm. If you do change any settings, unplug the EZ-? and spin the engine with the starter to equalize the belt tension, then check again, etc.
The WSM specs for all 928 32V cams equate to the following, measured with the 32V'r, with the engine cold.
cyls 1-4: 2° retard
cyls 5-8: 0°
For the best results (if you can stand the heat) to set both sides to 0°, with the engine hot/warm. If you do change any settings, unplug the EZ-? and spin the engine with the starter to equalize the belt tension, then check again, etc.
#38
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Whatever Dude .... I set my GTS to that but I'm thinking you thought one should retart 3 degrees on an auto? I didn't know what you meant by ¼ and ⅝ ... now I know you meant banks 1-4 and 5-8 SHEESH
#39
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Advance on the auto, Mr. Man. (More torque, lower in rpm.)
Retard for a slower drop in HP after the peak, higher in rpm.
¼ and ⅝ are easier to say (and less offensive to folks who drive on the wrong side) than US passenger's side, US driver's side, and more specific than right, left.
Retard for a slower drop in HP after the peak, higher in rpm.
¼ and ⅝ are easier to say (and less offensive to folks who drive on the wrong side) than US passenger's side, US driver's side, and more specific than right, left.
#40
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Got it, thanks for the heads up. When I go to check it later, I'll use one of your tools, and see if it's moved any. BTW stop calling me a retard.
#41
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OK, if you stop calling me a tool.
#43
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