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Time to downgrade.. Engine STILL won't fit.

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Lessen

Lessen

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RC Driving Style
  1. Racing
Ok gentlemen, I've had my twin engine fun. But now it's time to go racin. I want to pull one engine out of my Maxx and turn it back into it's stock formation. For this I will need a basic .21 extended chassis plate. Here's the problem I have though....

When I orginally bought the twin chassis conversion the engines would not fit properly. I could not slide the engine close enough to the spur because the rear bumpout for the primary shaft on the tranny case got in the way of the screw on the end of the engine's shaft. I simply had a friend of mine make me a new plate with the engine mount holes moved 1/8" rearward. So if my engine wouldn't fit on that chassis it makes sense that it won't fit on a standard .21 chassis either. I don't understand what the issue is in the first place. Here's a short list...

OFNA/Picco .26 w/18T CB (will need smaller bell when downgrading)
RC Solutions 52T big block spur
New Era twin engine chassis (basically the same engine layout as normal .21 chassis)
New Era .21 motor mount

The New Era parts are supposed to be designed for .21-.28 engines. The problem will only be worse when I go to a smaller CB because the engine will have to be even closer to the tranny. What gives? I thought maybe I got a bad chassis plate to begin with but I checked the original (twin, unused) against a stocker and the engine mount holes are in the same exact place in respect to the tranny location. What can I do to make this stuff work?
 
I had the same problem with my dynamite conversion and my ofna/picco .26.
I have a 15t cb and an rc solutions 52t spur. I had to elongate the holes on the chassis and also had to make some shims to lift up the engine a little
 
interesting, what did you use to lift the engine mounts? Also, how high did you have to lift it? I don't have any alluminum, but I got some 3/8" carbon fiber stock I could use
 
I had the same kind of problem with my maxx with the new era kit. I was putting the sirio .27 on there, and the mount made the end of the crank jam up against the tranny case... when it was all the way away from the spur. Then, when i tryed moving it towards the spur, that pop out on the tranny was way too long to try to fit past, so i had a friend make me a custom engine mount that moved the engine back 1/8". Works perfectly now.
 
jmarzilli said:
http://i4.photobucket.com/albums/y129/jmarzilli/100_0646.jpg

I don't have access to much so I cut the metal braces that go under the stock skidplates.

I put both shims under the right side of the engine(closest to the muffler), It works very good.
Click to expand...

ok, so the shim isn't that thick really eh? ok, I can make something out of CF. I'll see what happens. I never thought about raising the engine. Thanks jmarzilli!
 
When I had my XTM 21 conversion, I couldn't slide the engine back far enough either, even with their typical adjustable mounts. I cut about 1/8 of an inch off the end of my OS 21 RG to give me the clearance I needed. There was still about 1/2 inch worth of threads inside the shaft for the cb bolt.

I obviously had to re-shim the flywheel and collet to have it almost touching the engine to have enough room on the end for a washer to hold the cb on.
 
hmmm. I didn't know this was so common. I don't know if I even have enough shaft to cut down. when all the clutch stuff is installed it comes right down to the very end of the shaft, perfectly actually.
 
I was using the savage 3-shoe flywheel, OFNA bell and RC-Solutions spur on my OS 21 RG. Granted, I didn't have much clearance, but I had a little. About 2mm with everything installed and a little button head screw holding on the cb.

You can see a couple gouges in my trans case from when I had really bad headon hits with something and the engine slid forward:
2004-0921-TMaxx-RCSolutionsSpur02.jpg
 
Yeah, on my sirio .27r, i have the fiorni (i dont know how to spell it anymore) turbo sliding clutch and flywheel with the ofna 15t cb and the rc solutions spur. The cb bearings were at the very end of the crank, so there was no room to cut. As lesson said, a perfect fit.
 
yeah, just like .21rc10gt. I don't even have enough room for a button head... even with the custom chassis I still had to use a countersunk screw.

by the look of that pic I will need to raise the engine up quite a bit to get over that bump out. I could probably have something made... how much would you say I'd have to raise? ... 1/2" 5/8" maybe? might be a better idea just to have a high engine mount made.
 
I have the adjustable mounts that allow it to slide back and forth, so i didn't have that much of a problem. If your gonna have something made, couldn't you just have new holes drilled a little further back on the chassis.
 
jmarzilli said:
I have the adjustable mounts that allow it to slide back and forth, so i didn't have that much of a problem. If your gonna have something made, couldn't you just have new holes drilled a little further back on the chassis.
Click to expand...

not really, I've had that done once already. you'd have to have a new chassis because the movement is smaller than the width of the hole. plus it severely limits suspension clearance which I didn't realize when I had it done.

what's this adjustable motor mount I keep hearing about? who's makes it?
 

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