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Old 07-13-2008, 05:53 PM   #1
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Default RC8 & RB-s7 ?

Needs some help with my rc8, ran it for the first time today, The s7 does not have enough bottom end power. set-up on buggy 16th cb, 1.0 springs, 063 pipe. Any ideas on clutch and pipe set-up.
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Old 07-13-2008, 05:55 PM   #2
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1.1 springs, not sure about pipe but try a long header for more bottom end? or how about going to a smaller clutch?
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Old 07-13-2008, 06:08 PM   #3
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Needs some help with my rc8, ran it for the first time today, The s7 does not have enough bottom end power. set-up on buggy 16th cb, 1.0 springs, 063 pipe. Any ideas on clutch and pipe set-up.

Is the 16 tooth clutch bell standard on the RC8? Do they have a 4.30 Ratio in the gearbox?

Just sounds high to me most of us run a 13, or a 14 tooth clutch bell. which will help on the bottom end in your case. But I dont know if that is the standard clutch bell on the RC8 I dont know to much bout that buggy.
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Old 07-13-2008, 06:10 PM   #4
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16 is stock
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Old 07-13-2008, 06:17 PM   #5
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I have an s7 on my RC8, and am happy with the bottom end I get out of my setup. I am running an extra .1mm head shim, 7mm restrictor, 30% fuel and MC-8 plugs. This is with a 17T clutch bell. This is with the 2035 pipe.

The s7 is never going to have the sheer grunt off idle like some other engines. If there is a jump right off a tight corner I have to run a bit wide and get a run, where some engines will blip right over. Off a mid speed corner or jump the power is incredible.

Start with the 1.1 clutch springs off the bat. They will provide an instant improvement. Also, I run the clutch spring in the soft direction (long end of the spring on the shoe) I run Impulse hard clutch shoes with no extra weight added.

I went from a Kyosho Femca 512 pipe to a 9886 to a 2035 pipe. Each pipe was sucessively better. I have settled on the 2035, and it is really good with the s7. It gives up just a bit of topend to the 9886 but provides more low and mid with better economy.

The 063 you have should have more bottom than the 9886. What brand 063 is it? Some of the imitation 063s have restrictive headers that can be smooted out with a dremel for better performance.

Also, check you bottom end needle. RBs need a lot of fuel on the bottom end to make good power. Try richening up the bottom to see if performance improves. I would swap the springs immidiately, and try playing with the tune before you run out and get another pipe.

If you want to try a 2035 pipe, the TT chrome version is $46 with header from Amain. It is much cheaper than the Factory Team version, and the same pipe.

Hope this helps.
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Old 07-13-2008, 06:17 PM   #6
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yes 16 is stk cb, I dont have enough snap with this set-up to clear small jumps coming out of a corner. When i have enough run up to a jump its fine. But I had a guy at the track drive it today thats the first thing he said.
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Old 07-13-2008, 06:21 PM   #7
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There is more speed to found in the clutch and gearing then you will ever find in a motor, especially when it comes to bottom end. I don't know much about the RC8 but I bet if you follow others advice and go to the 1.1 springs you will see an immediate improvement.
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Old 07-13-2008, 06:24 PM   #8
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largeorange, I running rb 063 pipe and w/192 header. I think that header number is right. The pipe came with the motor a combo kit.
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Old 07-13-2008, 06:31 PM   #9
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largeorange, I running rb 063 pipe and w/192 header. I think that header number is right. The pipe came with the motor a combo kit.
Sounds like you have the RB pipe, so no worries about quality. That header is the 92mm one. It is considered "short" but that is the one you want to run. Get those 1.1 springs on and it will be better. Also try fattening up the bottom. What plug are you running? if you are running the RB 6 get that out of there and try a MC-8 (possibly a MC-9 if you are running 30% without an extra head shim). That will help with the bottom as well. I put a 6 back in my engine once, and noticed the difference right away.
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Old 07-13-2008, 06:33 PM   #10
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Hopefully this will get me in the right direction, thanks for the ideas, the kit only came with 1.0 spring I'll pick me up some springs this week.
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Old 07-13-2008, 06:40 PM   #11
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Sounds like you have the RB pipe, so no worries about quality. That header is the 92mm one. It is considered "short" but that is the one you want to run. Get those 1.1 springs on and it will be better. Also try fattening up the bottom. What plug are you running? if you are running the RB 6 get that out of there and try a MC-8 (possibly a MC-9 if you are running 30% without an extra head shim). That will help with the bottom as well. I put a 6 back in my engine once, and noticed the difference right away.
The plug is a OD 99. and I'm running OD fuel 20%. When you said mc-8 are you talking about a McCory plug. I have been adjusting the lsn trying to get the motor to have a steady idle may be to lean on the bottom. Glad to know the pipe is correct with the header.
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Old 07-13-2008, 06:43 PM   #12
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You actually want the motor to load up after just a few seconds at idle when cold. It should take a couple minutes of warm up to start cleaning out on the bottom.
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Old 07-13-2008, 06:50 PM   #13
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The plug is a OD 99. and I'm running OD fuel 20%. When you said mc-8 are you talking about a McCory plug. I have been adjusting the lsn trying to get the motor to have a steady idle may be to lean on the bottom. Glad to know the pipe is correct with the header.

Yes I am talking about the Mc Coy plugs. I believe the OD99 is colder than the MC-8. Since you are running 20% try the MC-8 as is, and see if there is any gain. If your idle is not steady, the tune is not quite right, which is good news for you as performance will get better when you get it nailed down. My car will literially sit and idle for 2 minutes easily. If the tune is right it should start to load up at idle after 10-15 seconds or so. This will happen quicker as you run colder and colder plugs.
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Old 07-13-2008, 07:22 PM   #14
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When It comes to Tunning the RB's, I wouldnt listen to the Fat bottum, lean top Theory..I used to run them like that, my motor was ok, but i then re-tuned it per there web site Faq's section ,and my Motor was crisper, and got over 1min more runtime.. check this link out for tunning help.
http://www.rbproducts.com/mainEn.php...e%20carburetor
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Old 07-13-2008, 08:15 PM   #15
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When It comes to Tunning the RB's, I wouldnt listen to the Fat bottum, lean top Theory..I used to run them like that, my motor was ok, but i then re-tuned it per there web site Faq's section ,and my Motor was crisper, and got over 1min more runtime.. check this link out for tunning help.
http://www.rbproducts.com/mainEn.php...e%20carburetor

It's not tuning it to the point of being fat. It is giving it fuel to make power. He said it is not idline steady, so clearly there is a bottom end issue, and it probably needs more fuel.
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