I got a racing mower for cheap, and I'm trying to squeeze as much as I can out of her with minimal investment. I want to keep stock internals, as I'm on a very limited window of time. I'm doing the standard eyebrow shave, intake/exhaust porting, milling the head down, and advancing the timing, but I'm guessing on some of this. I need some input from people who know more about this stuff.
I am a machinist and off-road race car fabricator, so some of the stuff I'm making is kinda fancy. 1-1/2" titanium exhaust, 2" aluminum intake, but these are just materials I had sitting around, so really I'm still at zero dollars invested in upgrades. I am trying to stay close to that number.
The carb was mutilated by the previous owner, so it's gotta be replaced, and I think I should be shopping for a bigger unit to accomidate the higher flow. I don't know about interchangeability though, and am hoping someone can guide my in the right direction there. I also don't know what is a safe limit on compression. By my math, the stock compression is about 8:1, and if I shave .05" off that should put me about 9:1. I'd like to go even higher, and I have access to 115 octane leaded race gas, so I want to take it as high as I can without blowing the motor up.
Here is the beginning of the titanium exhaust, and the mower as it sits now while I beef up the front end. We are doing our next race on a rockcrawling course, and I think keeping the wheels on is going to be more important than power on this one. I still need that HP though!
I am a machinist and off-road race car fabricator, so some of the stuff I'm making is kinda fancy. 1-1/2" titanium exhaust, 2" aluminum intake, but these are just materials I had sitting around, so really I'm still at zero dollars invested in upgrades. I am trying to stay close to that number.
The carb was mutilated by the previous owner, so it's gotta be replaced, and I think I should be shopping for a bigger unit to accomidate the higher flow. I don't know about interchangeability though, and am hoping someone can guide my in the right direction there. I also don't know what is a safe limit on compression. By my math, the stock compression is about 8:1, and if I shave .05" off that should put me about 9:1. I'd like to go even higher, and I have access to 115 octane leaded race gas, so I want to take it as high as I can without blowing the motor up.
Here is the beginning of the titanium exhaust, and the mower as it sits now while I beef up the front end. We are doing our next race on a rockcrawling course, and I think keeping the wheels on is going to be more important than power on this one. I still need that HP though!
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