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compression- mechanical vs calculated

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Old Jan 23, 2015 | 06:14 AM
  #11  
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ran 18.5 compression on our 150" P/G bike,ran C18 fuel
 
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Old Jan 23, 2015 | 09:34 AM
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Originally Posted by prodrag1320
ran 18.5 compression on our 150" P/G bike,ran C18 fuel
Clamping force on the heads gasket becomes very important!
 
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Old Jan 23, 2015 | 09:38 AM
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All I can say is WOW! I would love to know what it feels like to launch a bike like that just once!

I am sure most everyone else on here will agree that us shadetree guys in our own garages wrenching whenever we can, really appreciate the advice the professionals like Kirby and Scott have given us. Thank you guys so much for your active participation on these boards. I know it isn't easy answering the same questions over and over again- it takes time out of your day. So again, Thank you!
 
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Old Jan 23, 2015 | 09:38 AM
  #14  
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no head gaskets,just machined surfaces with a .040 fire ring (.039 cut in the head)
 
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Old Jan 23, 2015 | 09:40 AM
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Originally Posted by saz
All I can say is WOW! I would love to know what it feels like to launch a bike like that just once!

I am sure most everyone else on here will agree that us shadetree guys in our own garages wrenching whenever we can, really appreciate the advice the professionals like Kirby and Scott have given us. Thank you guys so much for your active participation on these boards. I know it isn't easy answering the same questions over and over again- it takes time out of your day. So again, Thank you!

we`re talking gas bikes,sure their fast (we ran 8.14 @ 160 in the 1/4),my nitro bike goes 167 in the 1/8 mile & 190 in the 1/4,THATS fast!!
 
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Old Jan 23, 2015 | 09:49 AM
  #16  
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Originally Posted by prodrag1320
we`re talking gas bikes,sure their fast (we ran 8.14 @ 160 in the 1/4),my nitro bike goes 167 in the 1/8 mile & 190 in the 1/4,THATS fast!!
Yes, yes it is. Fastest anything I have owned was a 70 GTO, 502BBC, brodix heads, lunati solid roller, 11:1, TH400 and 4.10's. All steel on 10.5" street tires, through the exhaust and a solid shot of nitrous was a 10.87 @ 127. I miss that car, but I still have the motor and tranny........ Needs a firebird or camaro to go in......
 
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Old Jan 23, 2015 | 10:03 AM
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Originally Posted by senna
Clamping force on the heads gasket becomes very important!
No head or base gasket here.
.040" firelip protusion on the finless duticle iron cylinder, and a .037" c/bore in the head creating a "crush" fitment.
5 bolt Shovel-style bolt circle in STD oval-port Evo castings, with a 4 bolt Shovel base, nutted to the cases studs.
7 hp-rated Hitachi starter motor, tired to 2, 1000 cca batteries making 24 volts in the starter cart.
Scott
 
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Old Jan 23, 2015 | 10:12 AM
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Friend of the shop just sold his Outlaw drag sled.
3.45et/145mph..............on snow, not ice or grass..........in 500ft!!!!!!!!
He said enough. Just too much to try to control.
Her also held the 1/4 mile world asphalt record on another snowmobile at one time, no so long ago. It had an OSP engine in it.
6.80 something @ 185 plus mph.
I manufactured some of the steering components on that asphalt sled.
Scott
 
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Old Jan 23, 2015 | 10:21 AM
  #19  
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Originally Posted by Hillsidecycle.com
No head or base gasket here.
.040" firelip protusion on the finless duticle iron cylinder, and a .037" c/bore in the head creating a "crush" fitment.
5 bolt Shovel-style bolt circle in STD oval-port Evo castings, with a 4 bolt Shovel base, nutted to the cases studs.
7 hp-rated Hitachi starter motor, tired to 2, 1000 cca batteries making 24 volts in the starter cart.
Scott
Thanks for the details. That was my point. You don't just put more dome on the piston and say I'm running 18 to 1 CR. it requires beefing up a lot of related parts.
 
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Old Jan 23, 2015 | 12:11 PM
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.........and then there is the driveline and chassis...........
Scott
 
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