Engine build questions

B

BackyardKart

New member
I'm new to this forum. Let me start with I'm looking for information and help on this project. I'm not going to race on a track. Just buddies having fun in a old parking lot. With that said let me tell y'all what I have a old racing go kart frame with tires,seat, brakes and a steering wheel. A briggs 5hp flathead in pieces not sure if it a raptor 1,2,or 3. Looks like it might be a aluminum bore with what looks to be a stock parts except the cam and valves springs. Cam looks like. 94-ss cheater and double valve springs. The block looks to have a little amateur work done. The bore is scared but not oversized. The valves port have the only noticeable work done. Someone tried to port them out. And I have a tillotson carb numbers say hl-314a. So my question how should I build this motor? I kinda want it to run alcohol. Let me know your ideas please?

Should I bore it out?
Should I run a longer rod?
What size cam should I run?
Should have work done to the head?
Valves?
Etc?
 
Welcome to Bobs, See if a magnet will stick to the cylinder bore. Then fill out your location and post back. Then we will know what the cylinder is and we might find someone near you that could make your rebuild go quicker and easy.
 
Thanks. Well the magnet doesn't stick. I have two blocks that are aluminum. Should I go with a steel bore or will the aluminum be alright? My location is now filled out. I have done some searching for shop in my area and has no luck.
 
Aluminum bore will be fine, you just need a piston that is made for that, a stock raptor piston is a chrome plated piston and will work. With the cam you have a stock length rod will be fine because your not gonna want to go over about 7500 or so rpms. With bigger cams and higher rpm's then you need the long rods. The 314A is an alky carb and will only work for ya with alky , so your good there. Hopefully it has a billet stock length rod which is the only way it will live. No valve work needed at this time and no head work needed with the cam you have. If your real new to this stuff you should just have it bored enough to clean up the scarring and go with all the parts you have, it will run pretty good, probably make about 12 to 14 HP, and will be basically what we call a Super stock. Jon
 
Ok sounds good. So I should use the stock crank and valves, head etc. I do have some double valve springs. Would it be a waste to put those in? How can I identify the type of cam I have? I don't know whole about what I got. I bought from a guy in pieces who bought from a guy in pieces and so on. And I would like to know what I'm putting in it so I know and if anyone ask I can tell them. I new to building one for performance reasons. I'm good with putting it back stock. Thanks for the help and the information so far.
 
Anyone have a website I can use to identify the cam I have? No numbers I can make out on it. I can see someone scratch elite cams into it.
 
Use the stock crank, it will handle high rpm if you go more modified, same for stock valves , don't need bigger until you go much bigger with engine size. Cams are basically gonna be stock lift .233 then outlaw stock, some stuff around .260 then a big jump to limited mod which are from .380 to .450 without a whole lot in between. 94ss will be a good start with no head work needed. Jon
 
Ok thanks. I'm not sure what the cam I have is. The lobes are flat on top. I will try and figure it out. If I can't I will buy one used if I can find one for a good price. Not trying spend a lot in this project. It's just a backyard toy and learning experience.
 
use a caliper measure the base circle , then measure the lobe. subtract the base from the lobe that will give you your lift.
.233 is stock lift .290 up is modified.
 
The flat part on the came gives you the duration with a controlled lift cam, the slapper cams throw the valve to the top of the head so the time it takes to get back to the lifter that's your duration. On a controlled lift there obviously no slap in it.... That's why there flat
 
Anyone here from VA? If so I'm looking for some shops or a engine builder in the of Richmond area. I have googled shops with no luck. I have found a couple but nothing close to me.
 
Hey bud in your area you have higgy or Im about 2 hours from Richmond would be glad to help you out Pm if your interested.
 
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