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supercharger 3.3

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yea beason ill bet your right. i should get mine going tomarrow. if it doesn't work right ill sent a you told me so letter
 
sunday afternoon to hot to run my rc truck. you know i need a name for my truck, killer? well yesterday i went to the motorcycle drag races. got to sniff some nitro, that ALLWAYS makes me feel better. there was some fast scooters gas in the low 8s and hi 7s nitro low 7s hi 6s.
 
supercharger second update

sunday evening. well i had put two check valves in the pressure lines. the only way it would run was to run it it at very high rpm. and burned a ton of fuel. so i thought it best to remove the check valves to get more pressure. i ran the starter so much it just stoped. then i removed the check valves. will have to wait till mon to try it again.
 
tue 2:30 pm mark this day in your day book. i got the supercharger to run on my 3.3. i can't tell if its faster or not. had to do LOTS of adjusting. it seems to me that if you get mid-range right then high speed is lean. if you get high speed right then mid-range is fat. iam starting to think that the carb is good at one end OR the other but not both. of course its not a real carburetor. its cross between a carb and fuel injection. my son thought i should name my t-maxx, ok here it is "KILLER" cause i stand so long trying to get it started my legs are killing me
 
tue 2:30 pm mark this day in your day book. i got the supercharger to run on my 3.3. i can't tell if its faster or not. had to do LOTS of adjusting. it seems to me that if you get mid-range right then high speed is lean. if you get high speed right then mid-range is fat. iam starting to think that the carb is good at one end OR the other but not both. of course its not a real carburetor. its cross between a carb and fuel injection. my son thought i should name my t-maxx, ok here it is "KILLER" cause i stand so long trying to get it started my legs are killing me
 
yep i was just thinking the same thing. i did buy a head shim set, .008, .012, .016. is that enough? i think i need an other set. is there a better carb that will work on my t-maxx? i just mixed a 16 oz bottle of 35% nitro.
 
well wat I'm thinking is that real cars with supercharger have low comp so i say go with .012 or .016
 
For a supercharger to work effectively there are other things that need done that are not possible on a glow engine.
As you stated, the carb is good for one end or the other. The first part of that is the rpm the sc is turning, it's look like it would be way too low to make much if any boost. So if any boost is there, it's not until you get near top end. The second is the way the housing is designed on these sc's, there is no real compression occuring. Then the fuel mixture needs to be adjusted more eficiently than these carbs can do.
The other big problem is ignition timing. As you build boost, the timing needs to be retarded. Glow plugs progressively advance timing.
 
racer why do you say it has no real compression? are you talking about the supercharger or the 3.3 engine?
 
ok guys I told YOU so. i just run two tanks of 35%. it ran great. but iam not sure it makes much more power, it is enough to go up on the homemade wheely bar. IT CAN BE DONE.
 
moe7404 said:
racer why do you say it has no real compression? are you talking about the supercharger or the 3.3 engine?
Click to expand...

He's referring to the actual supercharger itself. I have one of these things and the tolerances on it are not all that close. It's a very inefficient machine.
 
moe7404 said:
ok guys I told YOU so. i just run two tanks of 35%. it ran great. but iam not sure it makes much more power, it is enough to go up on the homemade wheely bar. IT CAN BE DONE.
Click to expand...

Wether or not you CAN run with it was never my point. Based on my years of experience with turbos and sc's I don't think it can make any boost therefore you hassle with it for no gain.

By not making compression,I'm talking about the sc. There's too much clearance around the compressor wheel,the wheel is a very poor design and the compressor housing is just too open. Plus with the single sealed bearing, there is no way it would withstand enough rpm to build boost.
 
well racer. i do have to agree that the sc is not well made. however i have no way of knowing how much, if any pressure it builds up. two things happened when runnig the 3.3, one was that the hotter it got the better it ran, on the first tank. the second tank seemed to need the fuel readjusted. there wasn't more than 30 sec between end of first tank and start of the second tank. its amazing how much one can learn even when your 60.
 
ok, RBI SUPERCHARGERS................first things first take it apart and make and fit a paper gasket and seal it with gasket sealer. (you may also notice that the veins are straight and the design is pretty naff with no "guide channel/flute" for the "compressed" air to be channelled through to the output and thus into the carburettor

Second, for the SC to be of any use, u will need the additional "overdrive" pulley to create adequite boost through the RPM range since the original pulley is of no use right from the get go.

third, you will need a pressure tap to mount to the SC, then feed a line from that, to a "Y" connector that also holds the line from the exhaust.

FOURTH, you need to install non return valves in the pressure lines, one in the SC pressure line and one in the exhaust pressure line to stop the fuel tank pressure bleeding off through the SC or exhaust pressure lines.

I fitted one to my O.S .30 engine a while back against a LOT of advice not to do so, i should have listened.

Initial tuning was a bitch, general running was not much better than stock and the power difference was minimal to say the least.

Firstly, one end was lean with the other rich, then it was the total opposite. I bought and fitted a 3 needle carb, that changed the tuning characteristics, and i got the engine tuned in perfectly. Next run, complete retune all over again.

I then R#removed the SC, retuned the engine once, and it held it's tune to the day i swapped out the engine.

The only upside, was that the pressure delivered to the tank gave better throttle response through the RPM range due to the better fuel delivery.

Essentially, the only thing the SC is good for, is boosting fuel pressure.

In short, take it off, sell it, bin it, whatever, just do not use it, its more trouble than its worth, and for what you paid, you could have fitted a decent new engine to give you the power you seek.

As to pressure, you would be lucky if you got 5 - 6 psi from it !!!!!!!!!!!!!!!!!!!!!!!
 
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I agree, i had a supercharger on my 3.3 and i hated it, i still have that useless piece of aluminum in my tool box just taking up space, i removed the supercharger and the 3.3 ran awesome, as a matter of fact i wish i still had that engine but someone that needed it got it so no biggie, but at any rate instead of buying that supercharger i wish i would have just done a BB conversion first, i did eventually do the BB conversion, and the power increase from the SC 3.3 to the picco .26 is phenomenal, i mean huge, so imho keep the supercharger for a shelf queen that never gets run for bragging rights but don't use it on a rig that you are actually gonna use, it doesn't help enough to make it worth buying
 
well rob......... theres a suprise !! lol mines going in the "shelf queen" box, prolly never to be used again !!!

btw, c u on yahoo !!
 
well plainly and simply put. . .RB INNOVATIONS SUPERCHARGERS SUCK!!!!!
sorry for anyone that actually likes them
 

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