Crane cam for Briggs 5hp flathead
Having just gone through indexing an unknown cam, 232 is a very common lift number on several cams used for Flat Heads. Here are the numbers I arrived at using a home made degree wheel. You can see where the overlap is by doing this, and get an idea of how your cam compares to others out there.
The problem with all of this is that most consumers simply buy off the shelf parts, slap in the cam and if the MFGR says "our springs are recommended" they buy them too. Great sales gimmick. Welding up the exhaust lifter boss inside of the engine is pretty much a standard modification recommended by almost all Cam grinders for these engines. Other than that, I'd say your cam is okay with stock valve train.
http://www.oldminibikes.com/forum/ph...m/Raptor12.JPG
Intake:
Lash: .008
Starts to Open: 17
Starts to Close: 100
Center Line: 100
Exhaust:
Lash: .006
Starts to Open: 54
Starts to Close: 78
Center Line: 115
Max Lift: .231
The problem with all of this is that most consumers simply buy off the shelf parts, slap in the cam and if the MFGR says "our springs are recommended" they buy them too. Great sales gimmick. Welding up the exhaust lifter boss inside of the engine is pretty much a standard modification recommended by almost all Cam grinders for these engines. Other than that, I'd say your cam is okay with stock valve train.
http://www.oldminibikes.com/forum/ph...m/Raptor12.JPG
Intake:
Lash: .008
Starts to Open: 17
Starts to Close: 100
Center Line: 100
Exhaust:
Lash: .006
Starts to Open: 54
Starts to Close: 78
Center Line: 115
Max Lift: .231
I have a Crane cam in one of my motors. I bought it without benefit of a cam card like you! When Crane entered the kart market they used what they thought would work well, based upon automotive technology. They never adapted a fast ramp or the "slapper" type cam. That is part of the reason they did not last long in the kart arena. I have done a little bit of research and their cams were too mild to win races!
Welding the lifter bore is not a bad idea...until your welder messes it up! A used block is going to have oil in the pores of the metal. To get a clean weld you will need to bake it and clean it for surgery! If you are able to get it welded, you may get distorted lifter bores which will have to redone. Unless you are going to scream it wide open at 7K RPM or higher, constantly for the 20 lap main, I don't know that I would get that done!
just my .02 and I am a dummy with only a hammer and screwdriver!
Welding the lifter bore is not a bad idea...until your welder messes it up! A used block is going to have oil in the pores of the metal. To get a clean weld you will need to bake it and clean it for surgery! If you are able to get it welded, you may get distorted lifter bores which will have to redone. Unless you are going to scream it wide open at 7K RPM or higher, constantly for the 20 lap main, I don't know that I would get that done!
just my .02 and I am a dummy with only a hammer and screwdriver!
You are correct Eric, I love welding cast aluminum but man once it gets oil in it, it is a real pain in the arse to get it done right.
Funny, I just bought my first "small engine" degree wheel, to go along with the big car degree wheel lol.
OP, using a degree wheel and dial indicator can allow you to measure all of the specs of your cam. Then you can make your own cam card to keep with that cam to keep track of its specs.
Funny, I just bought my first "small engine" degree wheel, to go along with the big car degree wheel lol.
OP, using a degree wheel and dial indicator can allow you to measure all of the specs of your cam. Then you can make your own cam card to keep with that cam to keep track of its specs.