| Author | Message | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 484 Registered: 10-2002 |
Thanks again Bill. I do understand the no backing up rule. Not a good thing to do. It also makes total sense to me about the offset needle for the indicator. While at work tomorrow I'll try and do a "government project" and make something up. That is an excellent idea! I've said it a hundred times and I'll say it again, this fchat board is priceless! | ||
| Bill Sebestyen (Bill308)
Member Username: Bill308 Post Number: 513 Registered: 5-2001 |
One more point Jeff, your dial indicator must be aligned very close to the lifter axis. Any angular error will result in lift error. I had to make and fit an offset dial indicator needle to satisfy this requirement. | ||
| Bill Sebestyen (Bill308)
Member Username: Bill308 Post Number: 512 Registered: 5-2001 |
One other thought Jeff, the measurements must be taken in the engine running direction of rotation. No backing up is allowed for correct cam timing measurements. | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 482 Registered: 10-2002 |
You are correct Bill if my closing event reading is right, my cam lobe is not symmetrical. If my numbers are correct which I doubt...then a chunk of closing cam lobe ramp is "missing", I must recheck this again tomorrow. This is not an easy task for the inexperienced, so many little variations. JRV...thank you for playing "too much information" ! | ||
| Bill Sebestyen (Bill308)
Member Username: Bill308 Post Number: 510 Registered: 5-2001 |
Jeff, If your measurements are correct, your numbers are saying the cam is not symetrical. Your measurements show the cam duration of (17+28+180)=225 crank degrees. Max open should be 225/2-17= 95 degrees ATDC, if the cam is symetrical. Is something else happening here? | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 2299 Registered: 11-2002 |
>>I hear that Mars is closer to the Earth tonight than it has been in something like 60,000 years, so maybe that has something to do with it.<< wonder if that explains why I'm hornier than a 3 tailed tom cat??? | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 480 Registered: 10-2002 |
LOL....tanks fur da edgamication JRV ! I'll go through the procedure again tomorrow. It is odd that my numbers would be so close except for the closing event. Therefore it has to be something I did. Although..I hear that Mars is closer to the Earth tonight than it has been in something like 60,000 years, so maybe that has something to do with it. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 2298 Registered: 11-2002 |
Unless you shaved one side of the cam can't see how it opens and peaks spot on yet closes way off? BTW: Gnats id what city folks calls dem, country folks calls dem knats..;-) | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 477 Registered: 10-2002 |
JRV, do you mean Gnat's Ass? (not Knat's Ass) Very primative, but it seems to "repeat" very well, and no I don't mean the gnat's ass. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 2296 Registered: 11-2002 |
Is that a Knats Ass I see you using for a pointer??? | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 476 Registered: 10-2002 |
Not a bad idea at that....thanks Tom! | ||
| Tom Jones (Ferrarioldman)
Junior Member Username: Ferrarioldman Post Number: 145 Registered: 6-2002 |
Jeff, Try setting your valve clearance to 0 and measure your timing when the valve has depressed .5 mm. Intake opening and exhaust closing are your most important numbers. tj | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 473 Registered: 10-2002 |
Well, I've tried to degree the intake cam for cylinders 1-6 tonight. Had some issues come up. The manual states you use 0.5mm clearance for timing cams, my valve clearance is less than this, so to get the stated clearance would require changing shims. Not an option for me. So I did another approach. I measured the entire lobe of the cam starting with it's lowest point and going around 360 degrees. It appears the lobe is symmetrical as I plotted out the lift at every 10 degrees. I figured I would use these readings of lift starting at the point when the lobe went above the "magic" 0.5mm and then again when it went below the 0.5mm threshold. I also attempted to measure when the lobe peak or "full open" position occurs. The peak had a dwell at full open of about 4 degrees. Then using this I interpolated the opening and closing points and compared them to the manual. Here is what I come up with so far. Bear in mind this is only for the intake on the 1-6 cylinder head: Manual States: open 16 before TDC closes 48 after BDC lobe peak at 106 after TDC My Results: open 17 before TDC closes 28 after BDC ....YIKES....WAY TO EARLY ! peak at 107 after TDC After doing this, I then re-verified that TDC on the degree wheel was spot-on with the flywheel, and it was good. I cannot explain the huge discrepancy with the closing point except an error occured. Any ideas out there? I will do this procedure again tomorrow as it MUST be a mistake I'm making. Thanks for all your input. Below are a couple of "curiosity pics". The indicator is not set up yet, so no comments as yet please.   |