wahturi

i was thinking it would be fun to put a .21 engine in a sedan. im sure people have done it, but is that common just for bashing? i know you couldnt race with that, but has anyone ever heard of or done this? i think it would be a fun project. how much more power do those motors generally make compared to .12 or .15?

Cartman

Go buy a Schumacher Fusion 21. they have done it for you inc a 3 speed gear box

wahturi

actually, seeing that car in a magazine last night is what got me thinking about it. i just thought it would be fun to do some custom fabrication. id rather figure it out instead of buy a new car though. do the mounting holes in .21 motors work with an rs4 chassie?

falcon68

No, A big block will not just drop in to a RS4, or any touring car for that matter. with the exception of that new Fusion. In order to put a big block in a HPI car, you will need a conversion kit. Wolfpack radicals makes a conversion kit that includes everything you will need to do this. All it is, is a flywheel, and motor mounts. I have done a big block conversion on a HPI NMT and I'm here to tell you, that a big block is really cool. I'm now toying with the notion of making one of my NRS4's a big block car. The biggest advantag of a big block is the torque and mid-range. The small blocks can't begin to compare. Speed all depends on how deep your pockets are.
One thing to keep in mind though. Before you do this conversion, you need to beef up your drivetrain to handle a big block's power. The stock plastic pulley's on the NRS4-2 is a big no-no. A few upgrades to the chassis are in order if you plan to have a reliable ride that doesn't break something when you nail it.

On my NMT big block, I had to get HD differential gears. I tried the stock parts for about a month, but I couldn't nail it from a stop, or get the truck in a bind. If I did, the engine's power would literally shatter the diff gears. Even with the HD differential gears, I've stripped a pinion gear by not being careful with throttle input.

wahturi

sounds fun. i have a nrs4 3 so i dont have to worry about a belt pulley. why do you need a new flywheel? is the one on the big block to big to fit without touching the chassis?

falcon68

Most big block engines have a SG shaft. That means that the pilot shaft is part of the crank. The mounting hole in the middle of the flywheel needs to be bigger than the one for the standerd cranks. As far as your NRS4-3, you will need to upgrade to the heavy duty differential gears for the NMT. You also need to upgrade your brakes.....

wahturi

you think it will just rip the teeth off my diff gears?? that sounds like a lot of power.

falcon68

The last stock diff. set I broke, The bigger differential gear came out in 4 pieces. It's the torque that kills those gears. The H.D.set isn't that suseptibal to breaking.

popsracer

wahturi;

ALL of the parts to do the transplant are availible from Wolfpack Radicals. It will easily cost more than what you paid for your entire car to do the conversion. $$$$$$$$$$$$$$$$!!!!!

falcon68

I believe that you spent more than $60 on your car, right?
The wolfpack conversion kit is $59.99 at bruckner hobbies. The differential mods will cost another $60.00. So it's definantly worth the investment.

wahturi

plus a .21 engine.. 200? that equals 320 right there, the price of my car. but what i wanted to do was machine all the parts myself so all i have to buy is the engine. could i get a .21 for around $100?

falcon68

Yes you can, Ofna makes a .21 that is about $110 brand new. They will have plenty of power for that RS4. If you just want to spend $200 dollars for the .21, be my guest, however, a $200 dollar engine will probably have far more power than the car can handle.

falcon68

Here's an example
There are a few engine's in that price range. You can also get the ofna hyper for about $135.
Hope that helps

wahturi

thanks. seeing that is tempting. i bet it would be so fast. 1.9 bhp!! compared to 3\4 bhp of my fe.

falcon68

AHH yes, decisions decisions!!!