Whats up OldMiniBikes, just got into go-karts thanks to one of my buddies and the speed urge has hit. i currently have a predator hemi 6.5 on my kart and wanted to bump up the power to gain top speed which is rpm bases some what and gain some more punch or power. Currently only has the governor removed, OldMiniBikes "stage 2 kit", and an arc billet flywheel. I need some advice/opinions on the rest of the build. I want to run the black mamba cam with 26 lb springs, mill the head and run a billet rod. this is where it gets iffy because i can deck it a bunch and run alky/meth or deck it less and run pump gas, and I need to take off the head to take pop out measurements to make sure i dont run any valve to piston issues. im new to this whole small engine game and could use some advice. Thanks again
Opinions on Predator Hemi Build
Alky should give you about a 1hp gain over gas, but I won't use it. I don't race, so buying it becomes a bit of an inconvenience. If you go alky, you're gonna want a better carb and exhaust. Warning: Speed addiction is expensive. What are your plans for the kart? Are you racing? Just racing with your buddy? Just cruising the neighborhood?
Are you going to br milling the head, or will you pay to have it done? What size valves do you have? The 26lb springs may be kinda hard on the stock valve train, but will definitely help keep you from floating your valves.
Are you going to br milling the head, or will you pay to have it done? What size valves do you have? The 26lb springs may be kinda hard on the stock valve train, but will definitely help keep you from floating your valves.
i am working on some parts from OldMiniBikes, just wanted to see what everyone thought. i cant seem to find the black mamba cam anywhere so I was gonna run the BP2 grind from dyno cams, .020 longer rod, 26lb springs, .010 thickness head gasket as well as some milling and porting. not sure how much to take off the head. i know the head gasket will net me .030 difference from the stock head gasket. any advice?
so i changed up my set up and ordered the parts. im currently out of town so waiting to get back to put this thing together. ordered the 308 dyno cam, nr racing stainless valve package with 37lb springs, retainers, and split keepers, lash caps and billet guide plate, stock length billet rod, .010 head gasket, .625 blueprinted arc carb, mild port and polish and milling .040 thou off the head. still not sure if i need chromoly push rods and how to measure. also was hoping to find a length of the head bolts so i can grab some grade 8 hardware.any help would be appreciated. will post pictures once i get home
Hammtheman the stainless valves you ordered will not fit the hemi head . The hemi has 5mm stems and you order 5.5 mm valves the fit everything else . The valves that come in the hemi will have e just fine for your build .,if you want better valves contact SI valves .
Also the 37 lb springs will not work in the head without machining pockets . And be careful the with the thin gasket and the milling of the head . Take off to much and the valves will hit the piston .
Also the 37 lb springs will not work in the head without machining pockets . And be careful the with the thin gasket and the milling of the head . Take off to much and the valves will hit the piston .
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