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Jethro 2t sniffer

Jethro 2t sniffer

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2broke2ride

2broke2ride

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The "3 finger" is whats in a 10-10. Thats interesting. A pro 10-10 automatic to be precise.
I thought my early 7-10 had the three finger ports but it's been forever since I looked at it. I'm glad we are documenting all of this, it will be good info for when I get back into mine. I still think I have a piston to cylinder mismatch or something that is effecting the port timing.
I also thought about possible "free porting" from the piston skirt maybe being too short. I will see when I get back to it.
I have to get through some customer work first.
 
Jethro 2t sniffer

Jethro 2t sniffer

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I thought my early 7-10 had the three finger ports but it's been forever since I looked at it. I'm glad we are documenting all of this, it will be good info for when I get back into mine. I still think I have a piston to cylinder mismatch or something that is effecting the port timing.
I also thought about possible "free porting" from the piston skirt maybe being too short. I will see when I get back to it.
I have to get through some customer work first.
Really hope ya get going
 
mogulmasher

mogulmasher

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From the land down under comes a new (and more likely) 82cc hp figure - well at least for the PM8200. 5.6 horsepower. Zoom in on this brochure.

https://www.ebay.com/itm/Vintage-Mc...185803?hash=item3b1a5a250b:g:Qg8AAOSwU1hbiyqt

Ron
Good info right there. I thought they'd be closer to 6hp though. Oh well.

HP numbers would be another thing to document here too. With verified sources, like brochures or actual Dyno runs. I was searching info on older 80/87cc Macs earlier and wound up on a vintage karting thread that quoted some old hp numbers from brochures. Highest I saw for one of the old 80cc motors was 5hp, but some models like D30 was 3.9hp.
 
mogulmasher

mogulmasher

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That horsepower figure does not tell the whole story as far as torque goes and how and when that applies.
Yes I agree 100%. Most old Macs have a lot more torque than their modern counterparts. HP certainly doesn't mean everything, it takes torque to get work done. If we could spin them a couple thousand more rpm the HP would be right up there too.
 
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