Road Racing the Flatty

RPM1

RPM1

Member
First, Thanks to Brian Carlson who answered all my stupid questions as best he could even when I gave hypothetical info!!!

With a much lighter driver AND adding 4 teeth to the axle our box stock Flathead (single bearing, alky, w/valve springs, billet rod, NO internal welding) its finally starting to come around. Brian suggested a target RPM of no more than 6500. We are just now sneaking up on 5800 so more gearing is yet to be added AND the fat guy needs to jump back in to see how gearing compares to the skinny guy!!!

Take a look at the onboard video, the RPM is clear. It runs good and seems ok the way it is. We dont want to saw it in 2, it is after all just a free trainer ride for newbies to try laydowns but the racer in me wants to find that lil more! I got 2 of these engines for free, generously donated to the project to help get new guys into road race karting..... I really don't want to build it up.

 
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Just have fun with it. Right now you've got little to nothing invested in it.
If you want to go faster and/or turn more rpm, you'll need to have it built up some at least.
The slapper style cams are hard on valve train - so if you can avoid them would be best.
Older 89-7exp cam or the likes would be better for longevity.
Using automotive style retainers and locks on the valve springs would be even more protection.
Fat guy will probably want 2 more teeth of gear over the skinny guy. :)

Anything folks can do to get more people involved in karting (the best kept secret in motorsports,) is appreciated.
Have fun with it.

-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
Some of the most fun track time I had was 2 years ago with a vintage kart and stock flatty....if I had the tank baffle, it would've been even more fun! Enjoy your project, and keep posting!
 
Its been suggested that I put the 2nd engine on the back too!!!! :ROFLMAO:

Seriously though, in the video above we had added 4 teeth AND put my skinny bro in it (60lb diff easy) and it only picked up 400 RPM on top. We are running a 34" circumference rear tire on it but in this clip from July (below) when I drove it I tried a 33" tire in the 2nd run to see if it would help. Nothing doing, it did make the car ass happy and more exciting to drive though!!!!

I think we should built another kart with the 2nd engine on it. Having a scrap with another one of these would be good fun and help the new guy that much more.

 
Looks like fun. I know you don’t really want to build them up but I’d highly suggest at least a billet rod. It may save you from putting a window in the front of the block one day. Stock rods will eventually give up.
 
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