Author Topic: Just got back from the dyno  (Read 2243 times)

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Offline MRieck

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Re: Just got back from the dyno
« Reply #75 on: October 15, 2018, 04:59:15 pm »
120/117............is that a mixture of jets?  Interesting.......My CBR shows same lean and runs best with 120 jets.....getting 122.5s for next year ;D
Dennis...yeah...we had to mix because he didn't have 4, 120's. Anyway....you get the idea with the lean spike and power increasing going leaner on the main. Different cam coming. That 125-30 is a funky cam that I think McGrew asked for for Daytona and the CR 750's.
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Offline Old Scrambler

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Re: Just got back from the dyno
« Reply #76 on: October 15, 2018, 09:14:08 pm »
It seems to work for me.........although my lobe centers are different and I don't much care if it works below 8,000 rpm ;D ;D
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Offline scottly

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Re: Just got back from the dyno
« Reply #77 on: October 15, 2018, 09:27:24 pm »
I watched the video at the start of this thread again, as well as looked at the charts; the dyno pulls are being started at too low RPM for a motor with a peak near 10K. No wonder there is a lean spike when the throttles are whacked open at 3K. ::) I learned to not bother starting pulls below 4K, reaching WFO near 5K. ;)
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Offline MRieck

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Re: Just got back from the dyno
« Reply #78 on: October 16, 2018, 03:51:39 pm »
It seems to work for me.........although my lobe centers are different and I don't much care if it works below 8,000 rpm ;D ;D
I hear you loud and clear brother. It does rip from 7 to 10,000.  ;)
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Offline MRieck

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Re: Just got back from the dyno
« Reply #79 on: October 16, 2018, 03:59:23 pm »
I watched the video at the start of this thread again, as well as looked at the charts; the dyno pulls are being started at too low RPM for a motor with a peak near 10K. No wonder there is a lean spike when the throttles are whacked open at 3K. ::) I learned to not bother starting pulls below 4K, reaching WFO near 5K. ;)
It initially goes rich from the accelerator pump @3,000 but the way it goes lean instantly after that is interesting (especially in light of the big vacuum drop going WFO). Usually the accelerator pump has a lingering effect but not in this case. I understand what you are saying and that is a good way to approach carbs with no pump. This cam has an interesting effect on low RPM....just listening to the idle tells you that (though you really can't hear it on the dyno).
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Offline scottly

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Re: Just got back from the dyno
« Reply #80 on: October 16, 2018, 07:03:12 pm »
My Webers have accelerator pumps. ;) Note the dip in the attached chart at 3000 RPM for the blue run, and then the lean spot, followed by the mid-range dip in the A/F; the mid-range dip is cam related. It's odd that a change of over 2.5 in the A/F at peak HP RPM only resulted in only a 2.2 HP increase?
I started getting some flaky A/F readings, so I pulled the O2 sensor out of the aluminum block, and found it was wet with sooty water, which evidently had condensed out from the exhaust; the sensor has a heater, but it doesn't heat up the block enough to keep moisture from condensing. You might mention that to Rick. 
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Online gschuld

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Re: Just got back from the dyno
« Reply #81 on: October 20, 2018, 06:28:36 pm »
Mike, the head you are using is what you refer to as a stage 4 head correct?

34/28 Kibblewhite 5mm stem valves, heavily ported K head yes?

Do you have flow numbers handy on that head that you would be willing to share?

George

Offline Bill/BentON Racing

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Re: Just got back from the dyno
« Reply #82 on: October 23, 2018, 06:42:03 pm »
Oh Mike, the old Falicons and crank are still in Purple Rain. ;D
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Offline MRieck

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Re: Just got back from the dyno
« Reply #83 on: October 23, 2018, 06:56:15 pm »
Mike, the head you are using is what you refer to as a stage 4 head correct?

34/28 Kibblewhite 5mm stem valves, heavily ported K head yes?

Do you have flow numbers handy on that head that you would be willing to share?

George
That is the valve set up George. I'd have to dig up the figures....If I remember correctly is was 79 CFM @ .400 lift and 10"
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Offline Tracksnblades1

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Re: Just got back from the dyno
« Reply #84 on: October 24, 2018, 09:29:28 pm »
Mike, the head you are using is what you refer to as a stage 4 head correct?

34/28 Kibblewhite 5mm stem valves, heavily ported K head yes?

Do you have flow numbers handy on that head that you would be willing to share?

George
That is the valve set up George. I'd have to dig up the figures....If I remember correctly is was 79 CFM @ .400 lift and 10"

I'm thinking 4 of them @ 79cfm each.........that will support 135.88 Horseys......
Just if one can get em all teamed up and hitched to the same sled and all pulling in the same direction......them high strung ones are a hand full.....Well Done...
« Last Edit: October 24, 2018, 09:32:14 pm by Tracksnblades1 »
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Offline MRieck

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Re: Just got back from the dyno
« Reply #85 on: October 30, 2018, 04:15:30 pm »
Mike, the head you are using is what you refer to as a stage 4 head correct?

34/28 Kibblewhite 5mm stem valves, heavily ported K head yes?

Do you have flow numbers handy on that head that you would be willing to share?

George
That is the valve set up George. I'd have to dig up the figures....If I remember correctly is was 79 CFM @ .400 lift and 10"

I'm thinking 4 of them @ 79cfm each.........that will support 135.88 Horseys......
Just if one can get em all teamed up and hitched to the same sled and all pulling in the same direction......them high strung ones are a hand full.....Well Done...
Thanks! My son disabled the "No Comment" on Youtube so I posted the #' up there. I'll be back on the dyno in the spring to test the 125-70 cam.
« Last Edit: October 30, 2018, 04:54:07 pm by MRieck »
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Offline dragracer

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Re: Just got back from the dyno
« Reply #86 on: October 30, 2018, 04:52:08 pm »
I've got just the package we need for testing that horsepower at the dragstrip. Lol

Offline Tracksnblades1

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Re: Just got back from the dyno
« Reply #87 on: October 30, 2018, 06:32:35 pm »
I've got just the package we need for testing that horsepower at the dragstrip. Lol

Drag racer,

Can you tell us about what we're looking at ( especially them wheels) that's a good horsepower test mule....?
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Just got back from the dyno
« Reply #88 on: October 30, 2018, 06:37:56 pm »
Damn Frank! yer cheating on the REAL bike... Looks great, get that engine built. I want to see it shredding tiny bits of ring seating surface out the exhaust on that first high compression pass in 3 weeks??
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Offline 754

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Re: Just got back from the dyno
« Reply #89 on: October 30, 2018, 08:03:43 pm »
Mitchell wheels , nice.. I Just picked up a 18x 5.5 myself... quite light. .
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Offline dragracer

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Re: Just got back from the dyno
« Reply #90 on: October 31, 2018, 12:11:12 am »
Didn't mean start stepping  on Mikes thread. Find more info on mine here.

I've got just the package we need for testing that horsepower at the dragstrip. Lol

Drag racer,

Can you tell us about what we're looking at ( especially them wheels) that's a good horsepower test mule....?

Offline MRieck

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Re: Just got back from the dyno
« Reply #91 on: October 31, 2018, 03:31:26 am »
Didn't mean start stepping  on Mikes thread. Find more info on mine here.

I've got just the package we need for testing that horsepower at the dragstrip. Lol

Drag racer,

Can you tell us about what we're looking at ( especially them wheels) that's a good horsepower test mule....?
No worries Frank.....see you in a couple of weeks.
Owner of the "Million Dollar CB"

 

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