STR33T_RAC3R

Hi,

I was wondering which is faster. The single speed of the twin speed dragsters?

Is the twin speed for less powerful engines .12 .15 where as the single speed is for the .18 and .21 or have i got that totally wrong?

Any reply would be great. Thanks.

2916jr

you can gear them to go the same mph but the 2 speed gets there faster

STR33T_RAC3R

Are you sure? Even with a fully modded .21 engine 2 speed would be better?

I was speaking to a guy about gears and he said that gear changes are slow. And with a powerful engine the momentum will be so intense the clutch will engage second and it will totally miss out first gear.

What type of spur clutch do dragsters use?

What Dragsters do you own if you don't mind me asking. I'm not saying your wrong i just want to make sure before i by one.

Oh and i mean faster as in which would be quicker down a scaled drag strip.

Paul Songas

As of this moment, the quickest nitro rail is a single speed direct drive car, very exotic. Most still use the standard 2 speed set up though.

STR33T_RAC3R

Okay so which does the fastest funny car down a scale quater use? Single or twin.

And do you know what type of engine the rail car you mentioned was using?

Paul Songas

The fast nitro funny cars are using the 2 speed set up for now. The direct drive set up takes up a lot of room they way it is set up on the rail. I know they are working on a direct drive chassis though. The motors are modded .21s.

griz11

Mugen on-road clutch is the one most people use. Also Mugen 2-speed trannys. No problem with the speed of the shift I don't know where that came from. Once the finger or shoe is moving fast enough it changes gears. The first gear is on a one-way bearing so once the 2nd speed engages the first gear is just along for the ride. Single speeds are faster but not many of them in anything but rail type cars to date. A few direct drives in the door cars but not many. Hard to find the finger type mugen tranny's now. RS4 finger is what people are using. I prefer the shoe type with lightened housings myself. Harder to learn to adjust but unless you go to the trouble of getting somone to make a 3 peg housing for the 2nd gear the finger type can take up to 1 full turn to engage or more if its worn. Adjusting the clutch is critical if you go for a single speed. Not something you'd want to tackle if this is your first car. Look for a light alloy clutch bell and pressure plate when you are buiding up the clutch. Also light alloy parts for the tranny cluster. The lower the weight of any rotating part the faster it will get up to speed.

Griz

STR33T_RAC3R

If i got the Team Walbern funny car should i change the spur set up for better performance or is it okay for a novice? And what type of flywheel and clutch bells would be good?

griz11

I use the standard Mugen flywheels. I had one lightened up a bit. Yea you need all the gears they make. And a wrench to get the pinions off the clutchbell unless you like to bleed. Mugen makes one but its a bit pricy. Unlike the electric cars nitros are very sensitive to the atmospheric conditions. Especially after they have been heavily modified. So you need to be able to change the gearing to suit the power you can get out of the motor on a given day. Get a clutch shoe lapper from Walbern as well. You aren't going to have any warm up laps or be running for 10-15 minutes at a time and you need to have that clutch shoe broken in and ready to go immediatly. A lapper will do that for you. The standard spring will work great. I've tried them all and always came back to the stock spring. Drill out the flyweights. Two holes in each one to make them lighter. Get a flanged bearing for the front of the clutchbell to keep it from moving around when it hits the shoe as well. It's actually better to have both the clutch bell bearings flanged but that requires modifying the nut and I never messed with it. Use the 6ft time to judge how well your settings are working. Get a lightweight clutchbell lightweight gear housings for the 2speed as well. The best bearings you can afford. I had good luck with Avid bearings. At a buck apiece you can change them frequently and not break the bank. Another thing I really go for is smoothness of the whole drive train. Sometimes you need to relieve the holes the bearings fit in until the bearings fit just right not too tight not too loose to get the smoothest operation. When its set up right you should be able to spin the rear wheel easily and it should spin for a lot longer than an on-road car for instance. Drag racing is preparation carried out to the nth degree. The cars look very simple but they aren't. Especially the nitro cars. Get on the internet and find out all you can about how atmospheric conditions can affect your performance and how to tune for the various conditions. For instance it gets really humid and hot here in the summer. A lot of times its too humid to get the nitro to light up completly so you lower the nitro percentage on those days. Plugs you need all of the heat ranges and you might use several in a day. I like the Novarossi plugs becuase there is a finer gap between them heat wise. Learn about deck height and how that affects timing of the engine. Plug type + deck height + nitro % = timing. You don't have to get to this extreme to have fun drag racing but if you are shooting for one of the national titles you are going to have to know all this and a lot more.

Griz

STR33T_RAC3R

So would a complete Mugen on road flywheel/clutch and pinion setup work fine with the spurs on a Team Walbern twin speed.
I have done some engine tuning. Never with a modded engine though i am planning on getting an engine modded form reid rc performance.
I know a place that i can get decent ceramics on Ebay so bearing wise i sould be okay.

Did you make your own Griz or is yours a kit?

griz11

My pro mod has a Walbern chassis. Ceramics don't really buy you anything. Ceramics excel at high temps. Which just don't exist in a car that might be on for a couple of minutes. I had Bill Possio mod my motors I kept asking for ceramic bearings and he talked me out of them. Yea use the whole mugen set-up clutch and tranny. The parts you would change are the clutch bell, pressure plate, 1st gear carrier and 2nd gear carrier. Get the lightest parts you can for anything that rotates. You can get someone to mill out the back of the flywheel but you can blow up motors real easy doing that when you clear them out on the line if you go too far. An essential item to get your clutch working properly is one of the lappers Walbern sells for the clutch shoe. Unless you lap that shoe it will take a few weeks of running to get it to the point where it works properly. Remember even a slow car only takes a couple of seconds to get to the finish line. If you last way into the rounds you might get 10 runs a day thats only 20 minutes of run time. And most of that is in the pits or on the line so the clutch can't get bedded in. Use the lapper and its ready to go as soon as you install the shoe. But don't just listen to me either. There are as many theories for the clutch as there are people running cars. Get on the imdra forum and rcdrags once it comes back up and pose the question get a lot of responces and then plan your own program to find out what works the best. Thats what its all about. You won't win by following in this game. The first few months you follow just like you do with any other type of car but sooner or later you have to break away and start experimenting. This whole drag racing thing is about going beyond what's known. All the top runners have their little secrets they have developed. Some part with them freely some don't. Its kinda like majicians. They won't show you a trick until you show them one in a lot of cases. Many of them don't want to waste time on somone until they show they are really interested. It takes a few months but once you are 'in' the information flows. I learned so much in a couple of years. Stuff that works no matter what kind of car you are running.

Griz

STR33T_RAC3R

Thaks griz.

griz11

So are you going to be ready for the World Finals in Oct Come on down its a blast.

Griz

STR33T_RAC3R

Yeah right.

The guys who take part in that usually take 10 cars each. I will be happy if i can get it running reliably and fast.