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Good work.
 

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Discussion Starter #62 (Edited)
Nice!.
Vin
Thanks Vin for all of your help, got the courage to start this project from you. Your pictures and descriptions on the master link was very helpful. Thank god that little sucker didn't get away from me I did use the 50 mm VVT wrench to help turn the cam and need to learn how to use them both to adjust the timing

Good work.
Thanks Ed,
I was held up for a week figuring out the TDC with the #1 lobes pointing in, from Steve Swchwitters instructions till you said you don't care which way the lobes are pointing, just that everything was lined up like it was when you started. Later I realized Steve never said TDC on # 1, I assumed it was the TDC on #1.
Plus all the other help you gave me and the valve for grinding made this job a lot easier for me,!

I owe you both big time! Hope to meet you guys someday!
 

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Will you be at Watkins Glen in September?
 

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Discussion Starter #64
Will you be at Watkins Glen in September?
Nope,

Only trip away from home this year will be the Alfa Romeo convention in Colorado Springs. Suppose to be starting a large building job this Spring/Summer that will limit my traveling for 2021.

Is that the sports car championship? Never been to it, never been to New York either. For some reason I thought that was in Alanta GA?
 

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Alfa's at the Glen is a once every five years event. The Vintage grand prix is every year and the featured marque rotates. It is our turn again this year. The Mitty is the big vintage/historic race at Atlanta and AR was the featured marque last year. My son lives in Colorado but he no longer drives an Alfa.
 

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Richard Jemison
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V V T Cam Timing
Before this thread ends I had some questions & concerns with the use, and more particularly the cam on-off iniations as it seems that your original settings are a bit contrary to common practice regarding cam lobe center and lobe separation angles and their effect on power building in RPM ranges.

Typically for lower range power and torque building for a strong street motor not exceeding say, 7000 RPM the common practice is to advance the cams lobe separation angle. ( If you set your LCs at 102/102 then your LSA is 102 and at that set-up it`s commonly called "Straight-Up" and the LCs are not advanced or retarded. This was common practice with factory set-ups years ago, and is a bit narrow LSA for these Nord engines )
If you set the cams at 100 intake and exhaust at 108 the result is a 104 LSD (and a LSD of 104-105 seems to give better performance in these motors) That 100/108 LC is a 104 LSAc advanced 4 degrees from "straight up" which would be 104/104 at the same LSA. That advanced position should enhance the lower RPM power band, probably peaking at 5K.
Advancing your VVT cams from 1000 RPM to 4000 RPM then cutting them off returning them to 105 / 102 from 4K to the engines redline should give you a stronger power band for the entire rev range.

Just my thoughts.Maybe Jim (4sfed) can correct or enhance this set-up situation using these 2 V V T units.
 

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I talked to Jim about this a few days ago. He said that there is little to be gained by advancing or retarding the exhaust cam other than for emissions control. His instructions to me when I set up my cams on the dyno were to find the best position for the exhaust cam and then leave it alone and work on the intake. 108 worked best for me with the 785 cam and the 457 was similar. I started at 104 for the intake and moved it to 101 and then 98 which was as far as I could go and still maintain valve to piston clearance. 98 was superior all the way from 3000 to about 6000 and above that they were the same. Jim said that it is possible that retarding the intake a little at high rpm may make a bit more power at the top end.
This was for a car with a street exhaust. A different exhaust configuration may perform best at something other than 108 and the same goes for different exhaust cams.
 

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I talked to Jim about this a few days ago. He said that there is little to be gained by advancing or retarding the exhaust cam other than for emissions control. His instructions to me when I set up my cams on the dyno were to find the best position for the exhaust cam and then leave it alone and work on the intake . . . (snip)
Let's just say ... for a normally aspirated engine ... once cam timing has been optimized for midrange, I haven't seen enough difference in power by retarding the intake to make dynamic timing worthwhile. Turbo engines are different. Cam timing affectsthe onset of boost, which greatly affects power.
 

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Discussion Starter #69 (Edited)
V V T Cam Timing
Before this thread ends I had some questions & concerns with the use, and more particularly the cam on-off iniations as it seems that your original settings are a bit contrary to common practice regarding cam lobe center and lobe separation angles and their effect on power building in RPM ranges.

Typically for lower range power and torque building for a strong street motor not exceeding say, 7000 RPM the common practice is to advance the cams lobe separation angle. ( If you set your LCs at 102/102 then your LSA is 102 and at that set-up it`s commonly called "Straight-Up" and the LCs are not advanced or retarded. This was common practice with factory set-ups years ago, and is a bit narrow LSA for these Nord engines )
If you set the cams at 100 intake and exhaust at 108 the result is a 104 LSD (and a LSD of 104-105 seems to give better performance in these motors) That 100/108 LC is a 104 LSAc advanced 4 degrees from "straight up" which would be 104/104 at the same LSA. That advanced position should enhance the lower RPM power band, probably peaking at 5K.
Advancing your VVT cams from 1000 RPM to 4000 RPM then cutting them off returning them to 105 / 102 from 4K to the engines redline should give you a stronger power band for the entire rev range.

Just my thoughts.Maybe Jim (4sfed) can correct or enhance this set-up situation using these 2 V V T units.
Richard,
I don't know if I no enough to answer the question and concerns?
I'm not planning on turning on the VVT's if that was the concern?

Edit:
Re read your post and I believe I understand it, I don't track the car anymore. Your cams and the way you set them up sure sounds promising.
 
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