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.21 engines, pullstart vs. nonpullstart

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kwong2001

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Well i'm doing a .21 conversion with an RS4 2. Anyways, I know on .12's it really matters if you have pullstart or non pullstart because that will dictate your engine mount and flywheel.

So my question is this, is it the same with .21's or do I not need to worry about that?
 
Yeah but will the .21 conversion engine mounts work with either pullstart or nonpullstart?
 
Kwong,
What the hell are you doing putting a .21 in that thing?
A good.12 will kick its ass.
If you want a digester get one....
 
FastEddy said:
Kwong,
What the hell are you doing putting a .21 in that thing?
A good.12 will kick its ass.
If you want a digester get one....
Click to expand...

Um, actually it'll be a .28 Wasp to be exact:D

I'll be running full robinson racing drivetrain components. I have robinson racing pinion gears and front/rear ball diff. The only part in the drivetrain that's plastic will be the gears.

The two speed will be the one from the nitro tc3.

So basically, the only parts that have protential braking is the spur gear and belts.
 
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Cuz i want a high speed basher...and i've always wanted to do a .21 conversion with a 1/10 onroad.
 
kwong, just an fyi, i have small blocks that tear the drivetrain apart in my super nitro. a .28 WILL snap axles every time you take it out. this is from my personal experience.
 
Is a .12 really that much better? And why? I have access to a .12 I could probably get for nothing............
 
it all depends on the car, and what the specific engine is. there are 12's that can't get out of thier own way, and other 12's that can put some sport big blocks to shame.
 
CorradoPsi said:
kwong, just an fyi, i have small blocks that tear the drivetrain apart in my super nitro. a .28 WILL snap axles every time you take it out. this is from my personal experience.
Click to expand...

I hear I can get some MIP CVD's from the Racer 2 kit....I really don't mind if I break anything, cuz i'll just find something better to replace it :)
 
parris001 said:
Recommend a .12 then. What's hot and what's not?
Click to expand...

start an appropriate thread and ill be more than happy to. no sense in highjacking this one.

kwong2001 said:
I hear I can get some MIP CVD's from the Racer 2 kit....I really don't mind if I break anything, cuz i'll just find something better to replace it :)
Click to expand...


i hope it works for you. although I've tried every axle out there, and snapped em all. so i went back to dogbones because they are the cheapest to replace when they do break. it twists the head right off the bone. usually in the diff cup so the cvds will only garrentee thats where it breaks since its reducing friction at the wheel end of the bone. you have to be carefull when cornering, if you spin out while on the power, you can kiss at least 1 usually 2 axles goodbye. also doughnuts are the biggest no-no in the book with lots of torque on hand. good luck with your conversion, hope i havent scared you too much. on a positive note, I've never snapped a belt from too much power, its always picking up a pebble that does that.
 
CorradoPsi said:
i hope it works for you. although I've tried every axle out there, and snapped em all. so i went back to dogbones because they are the cheapest to replace when they do break. it twists the head right off the bone. usually in the diff cup so the cvds will only garrentee thats where it breaks since its reducing friction at the wheel end of the bone. you have to be carefull when cornering, if you spin out while on the power, you can kiss at least 1 usually 2 axles goodbye. also doughnuts are the biggest no-no in the book with lots of torque on hand. good luck with your conversion, hope i havent scared you too much. on a positive note, I've never snapped a belt from too much power, its always picking up a pebble that does that.
Click to expand...

Well I won't be doing any cornering at all. This car will purely be a high speed straightline car. If I wanted handling, i wouldn't be putting in a .21 or using an RS4. Also, I probably won't be doing any donuts just cuz it'll kill my foam tires....unless i use some rubber tires ;)

I'm more excited than ever to do my project car
 
kwong2001 said:
Um, actually it'll be a .28 Wasp to be exact:D
Click to expand...
You seriously putting a Wasp .28 in there? Because holy poop that RS4 will haul ass!

I just got a Wasp .28 for my Inferno and that thing has so much compressoin I broke the pullstart before I even got it started once! I had to take off the Pullstarter and use a drill to get it started lol. That RS4 will hual some major ass with a Wasp .28!
 
If your looking for speed why don't you go with a 42,000 rpm small block geared for speed?

RPM=Speed
Displacement = Torque
 
I've got my nitro tc3 with a novarossi ns12s3. It can do 60mph in a very short distance. Probably with a bit more room i could squeeze a good 65mph out of it...especially with the 30% nitro I use. I wanna go faster, but run the car with the same distance as I did with the nitro tc3.

It's much of a trade off with .12's Your engine either turns super high rpms, makes tons of horsepower while losing your low end torque, or has very good off the line capabilities, but looses the top end power.

The only reason why my nitro tc3 does 60mph in the distance it has is because it gets off the line very quickly, horsepower is high, and the gearing is very high. Unfortunately, my powerband tops out in the lower RPM so I can't achieve the super high speeds I want, even with the gearing I have.

If I were to use a .12 that makes high rpm, high horsepower with a powerband that tops out high, I can get a much higher top speed. But much of the sacrifice will be in the low end. It will take a much larger distance to hit the speeds because you have to wait so long to get into the powerband. I know of no place that has that kind of distance with a smooth pavement. Even if I did, i'd have a lot of trouble seeing the car, which wouldn't be the most fun.

By using a .28 wasp, which is meant for a monster truck, I can get the low end I want, while still having incredible top end. Since it's rated at 2.8hp and 42k rpm's, even if the powerband falls off at 30k, there's a good chance much of the last 12k rpm will still be making more horsepower than my novarossi. I'll have such a light weight car that the powerband characteristic won't make as much of a difference like it does in .12's

So basically, by using the .28 wasp, the trade offs won't be as bad. I can still have an all around good car with over the top capabilities anywhere I go. The only thing left to worry about is getting the car to hook up, and parts breaking.

Besides, if I don't like it for any reason, i'll just put the engine in my savage...which is still in need of an engine ;)
 
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