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question about a briggs and a honda


kenwoods77's Avatar
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12-26-05, 01:56 PM   #1  
kenwoods77
question about a briggs and a honda

ok i have 2 problems......
1st im finishing up a go kart that ive been building on and off for a while. im up to the motor now, ive finished painting all the frame and accessories. i have a briggs 8hp industrial plus motor, and like any real guy i want more out of this motor. ive already got a exuast pipe for it thats hollowed out, but thats all. ive found a 10 horse that im gonna pull the carb off of becuase myne is shot on the 8hp. so ive got a bigger carb for it and the exaust, but now im stuck, i want more to it, that is relatively cheap. im going to be rebuilding it with all new gaskets, seals, new rings, but im stuck. idk what else i can do to it. any ideas will be greatly accepted.

now for the 2nd problem.
im building a mini chopper at my school and yet again im stuck at the motor situation. the school is suppling us with 5 hp honda motors for free, now can i hop that up easly, since im going to do a full rebuild it, or should i find a briggs 5hp, because there seems to be more stuff for the briggs 5hp, like cam,valves, and stuff like that. and where could i get parts? id prefur if i could hop up the honda because the motor is free, so any help on this will also be greatly accepted.

 
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12-26-05, 09:35 PM   #2  
lots of briggs performance parts on e bay....... for the honda i'm not sure of any performance parts for them.

 
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12-27-05, 06:54 PM   #3  
For your 8hp I'd get rid of the govenor and gear the cart to take advantage of the extra rpm's. I would get a proper exhaust. That hollowed out muffler isn't doing anything to help you. You can also make sure the new carb. bolts up to the engine nice and smooth. You don't want any sharp edges in the intake area where the carb meets the block. You can file/grind the rough casting around the valves to smooth things up. Make sure the case is well ventilated. You can run a reduced amount of oil and run a thinner oil to cut internal drag.

The Honda can be souped up but finding the parts is more difficult than a Briggs. The Honda is a great engine but it is not raced as much so there are not as many parts available. Do some online searches. I found several companies selling performance parts for racing go karts.

 
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12-28-05, 01:24 PM   #4  
wouldn't run it with a reduced amount of oil, gotta stay to the full mark, but running a good syn will reduce drag, 10w-30 mobil one would do great.

 
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12-28-05, 09:22 PM   #5  
kenwoods77
thanx for the help, anybody else with ideas dont be shy to post, where could i get an exaust system for it, on ebay ive only seen performance parts for 5 hp, would anything for a 5hp bold to the 8hp, like the cone air filters and exuast pipes?

= one other question=
i heard from a mechanic teacher at my school that use to run karts that you can make a head gasket out of a manila folder(spelling???) to raise compression?????? that sounds really wierd, but anybody that knows about this please let me know....thanx
KENWOOD

 
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12-28-05, 10:33 PM   #6  
never heard of the head gasket deal....... 5 and 8hp engines are different, so hardly no parts would fit, for exhaust..... steel pipe tubing, threaded and the right size to fit the threads in the exhaust port, cut to length.

 
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12-29-05, 04:19 PM   #7  
If you want to increase the compression a tiny bit I would look for a thin gasket material and not bother with plain old card stock (manilla folder). The folder will probably work for a while but I guess you would have to periodically check the torque on the head bolts.

First, if you make a header put a lot of work into bracing it very well. The header will need about 16"-24" pipe which will tend to vibrate and will crack the engine or the header if it can move or vibrate at all. Many factory made pipes are bent to wrap behind the seat or formed into a loop (bugle) shape to make all the pipe fit into a smaller space.

A smaller diameter pipe will tend to help the low and mid range torque where a larger diameter will help top end. Some pipes compromise and have both small and large diameter tubing. Headers are a bit of science and art so you will just have to play around until you find something that works well.

 
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12-29-05, 08:26 PM   #8  
could make a head gasket out of thin copper sheet. as for headers/pipes, be sure to wear ear plugs can get loud

 
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12-30-05, 12:13 AM   #9  
You can get a belt sander, put it upside down in a vise, turn it on, and set the head on it lightly and sand off head material (while constantly measuring) until you remove the amount you'd like to remove to increase compression. .010" is probably a good place to start, and probably about what you're going to do best with.

A straight pipe will work well to help the engine out. I'd use a straight threaded pipe with a brace welded to it that will bolt to the engine to keep it from vibrating loose and stripping the block. Get the pipe (non-galvanized) about 2 feet long, and spray some cheap spray paint on it. Start the engine and watch the pipe. The spot where the paint first begins to burn off is where you want to cut the pipe. (unless it's right where it connects to the engine, then look for the hottest spot farther back). This will tune the pipe fairly effectively to your engine.


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