6.5 clone parts help

[karl]

I have a 6.5hp blue harbor freight motor on my manco dingo go kart. It has a 30 series tc on it. I want to get the most low end power and torque out of it. Right now at full throttle it cant make it to 3600 rpm because the tc shifts into high gear. I can remove the governor but this motor probably wont go above 4000rpm. Also muffler. I want a free flowing muffler but a straight pipe is to loud. RVL muffler? I dont want to spend over $150.What is a good high lift cam for it? The motor has under 20 hours on it. Will a flat top piston and rings help? I can hone it for free. And help with the best parts and places to get them for my application would be appreciated. Thanks for reading.

 

[Doc Sprocket]

Sounds like you're a bit underpowered/overgeared. You could gear down a wee bit, increase the engines power output, or delay the driven's "shift" threshold. Or a combination of the above.

I had a similar problem with mine when I was geared at 4:1 final. I wasn't achieving the full governed RPM because I was running out of oomph in the top end. I slowed down the driven's response, but I really did not get a satisfactory result until I geared down to 4.8:1. Not only did that allow me to hit 3600, it allowed me to hit 4200 with the screw backed out. The lower ratio allowed a wee bit better takeoff, less stress on the belt, and I actually gained about 5mph top speed. That's right folks- gained top speed by gearing down.

Altering the driven's response time is free, regearing is cheap. You might want to try that first.

 

[birddog1148]

Can you change anything in the driver to alter where it comes in at?

here is a link to parts fore the clones
http://www.arcracing.com/servlet/StoreFront

 

[karl]

I wanted to get more speed with this ratio because it would HAUL.

This is the parts list I came up with from ARC racing.

1.Honda flat top piston 15.00

2.DJ-2290 stock size honda ZOT piston rings 12.50

3.RLV-4117 mini 91 muffler $15.95

4. Dj-1108 bsp-1 box stock racing cam $20.00



5. Then a head gasket and sidecover


The thing that im worried about is the valves hitting the piston with the flattop and higher lift cam. Will this happen?


And should I re- jet? What jet? And what Air cleaner?

 

[birddog1148]

I wanted to get more speed with this ratio because it would HAUL.

This is the parts list I came up with from ARC racing.

1.Honda flat top piston 15.00

2.DJ-2290 stock size honda ZOT piston rings 12.50

3.RLV-4117 mini 91 muffler $15.95

4. Dj-1108 bsp-1 box stock racing cam $20.00



5. Then a head gasket and sidecover


The thing that im worried about is the valves hitting the piston with the flattop and higher lift cam. Will this happen?


And should I re- jet? What jet? And what Air cleaner?

They have some videos on their site, Karttrax I think, he has a real god one on the carb. Get the addapter and an angled air filter, works good.

 

[karl]

They have some videos on their site, Karttrax I think, he has a real god one on the carb. Get the addapter and an angled air filter, works good.

Ok but can I use the flat top piston and the cam? And im gonna get the 8 buck adapter and filter.

 

[oldbikerarlo]

I wanted to get more speed with this ratio because it would HAUL.

This is the parts list I came up with from ARC racing.

1.Honda flat top piston 15.00

2.DJ-2290 stock size honda ZOT piston rings 12.50

3.RLV-4117 mini 91 muffler $15.95

4. Dj-1108 bsp-1 box stock racing cam $20.00



5. Then a head gasket and sidecover


The thing that im worried about is the valves hitting the piston with the flattop and higher lift cam. Will this happen?


And should I re- jet? What jet? And what Air cleaner?

The DJ-1108 cam is not a highlift cam it is ground to the top limit of a stock cam. it should work. Useing the stock rod with the extra compression of a flat top piston will more than likely end badly. Isn't the mini muffler for the wiener pipe? that is a big restriction. Did you check out the vid's, and blogs at ARC's site? they will answer a lot of the questions you are asking. then you'll be able to pick out the correct parts to get the performance you are after.

 

[karl]

http://www.arcracing.com/servlet/the-2/Billet-Connecting-rod-honda/Detail

Ok so this rod should work with it?

Isn't the mini muffler for the wiener pipe?

I was just gonna put a 90 degree elbow and thread the muffler in.

 

[oldbikerarlo]

OK a 90* elbow, and mini muffler, is like hooking a garden hose to a fire truck. So why put all the perfomance parts in and then restrick the exhaust. I can't figure out what your trying to do, OH and yes that rod would work.

 

[karl]

OK a 90* elbow, and mini muffler, is like hooking a garden hose to a fire truck. So why put all the perfomance parts in and then restrick the exhaust.

I cant put a straight pipe on it its to loud. What if I thread the mini muffler right into the block? I am not gonna be running the flat top piston and billet rod.

Im watching the vids and Im probably going with a MOD 2 cam, 18lbs valve springs, then the air filter. But im stuck on the muffler. A full size rlv is expensive and then I need a header. The mini rlv is $15 and I can thread it right in and is gonna be alot freer flowing then a stock muffler.

 

[oldbikerarlo]

Karl, Do yourself a favor and watch all of the vid's on ARC's site, and read all the blogs. then check out the differant kits they or other engine suppliers have. Figure out what you want then ask your questions. You are asking random qustions, and change your mind about what you want every post you make.

 

[CaptCanadia]

I don't know about your other problems and I didn't read the other posts about mufflers, but I heard that the RLV's don't do much.

 

[osso12]

Karl, Do yourself a favor and watch all of the vid's on ARC's site, and read all the blogs. then check out the differant kits they or other engine suppliers have. Figure out what you want then ask your questions. You are asking random qustions, and change your mind about what you want every post you make.

Not really. He is asking questions based on his given budget.
RLV's are high. I just spent over $400 on a yellow clone had to settle on the wiener mini pipe and muffler because I could not afford the $32 muffler or whatever it was in the end. Basically maybe like karl, I had purchased all I could with the money I had as far as performance. I did not want the mini pipe either and I am sure karl dont either, but he can always change to a RLV when he gets the money or can afford to change.
I think he is speaking from his given budget, only Karl can clarify this. People change theyre minds all the time when it comes to money. Nothing new there.

 

[oldbikerarlo]

I understand the money thing. If you did some research on the basics of engine building, then it would become clear that the wiener pipe, and mini muffler, is designed to be a restrictor for the Box Stock Class ,so if you try to cheat, with internals of the engine. the pipe and muffler hold back most of any performance gaines. It is somewhat better than the stock muffler, but limits you to stock performance.

IMO the place to start is the exhaust and carb flow. then as you can afford it get into the internals.

 

[Bluethunder3320]

car muffler!

 

[Doc Sprocket]

IMO the place to start is the exhaust and carb flow. then as you can afford it get into the internals.

I second that.

 

[machinist@large]

car muffler!

:arf:Thrush or cherry bomb? you didn't specify.

 

[karl]

Sounds like you're a bit underpowered/overgeared. You could gear down a wee bit, increase the engines power output, or delay the driven's "shift" threshold. Or a combination of the above.

I am gonna gear it down a bit, remove gov and low oil box, paper filter and the curved straight pipe that aims at the ground. Alot cheaper, and less confusing.