Author Topic: JMR billet engine build  (Read 22072 times)

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Offline Syscrush

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Re: JMR billet engine build
« Reply #125 on: July 31, 2017, 12:02:56 pm »
This thing looks very cool! I've been thinking of a data logging lambda sensor for a while for similar reasons. I'm taking a very hard look at this:

http://www.zeitronix.com/Products/zt2/zt2.shtml

Thanks for the pointer.
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There's nothing more expensive than a free bike...
FWIW, I'm not a shill for Race Tech - I've just got a thing for good suspension and the RTCE's are the most cost-effective mod for these old damping rod front ends.

Offline Don R

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Re: JMR billet engine build
« Reply #126 on: July 31, 2017, 09:13:17 pm »
 My drag car has a racepack data recorder on a 567" big block and at lower rpm's reversion will suck air back into the header between pulses and make spikes on the data recorder. crazy.
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Offline MRieck

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Re: JMR billet engine build
« Reply #127 on: August 01, 2017, 05:50:49 am »
My drag car has a racepack data recorder on a 567" big block and at lower rpm's reversion will suck air back into the header between pulses and make spikes on the data recorder. crazy.
Flow does go in both directions. ;D I am porting a CBX head which has....possibly....the worst ports I have seen. The most lateral ports on 1 & 6 can't be seen from the intake side which made me think they probably push more air through the port than pull it. ::) ;D
Owner of the "Million Dollar CB"

Offline Syscrush

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Re: JMR billet engine build
« Reply #128 on: August 29, 2017, 03:54:02 pm »
I am porting a CBX head which has....possibly....the worst ports I have seen. The most lateral ports on 1 & 6 can't be seen from the intake side which made me think they probably push more air through the port than pull it. ::) ;D
It really is interesting the design compromises made on that bike! And it's interesting that they did so much wrong but still managed to come up with the first 100hp production bike. Was it the first widely-available 4-valve head?

How badly is the flow mismatched between the different cylinders? I'd be really curious about how it looks with the carbs and airbox on, as I think the intake trumpets in the airbox are shorter on the outboard cyls to compensate for the longer runner length.
Life is precious: wear your f'n helmet!
There's nothing more expensive than a free bike...
FWIW, I'm not a shill for Race Tech - I've just got a thing for good suspension and the RTCE's are the most cost-effective mod for these old damping rod front ends.