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HPI K4.6 Engine

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Breakin update:

Did another 3/4 tank until the spur stripped :D I was driving on snow, hust a little left over from shoveling, so it wasn't even getting much grip. Anyway, it completely demolished a spur gear lol. I was afraid of usiing a platic with a .28, on my old savage I had a steel one. Anyway, I came prepared for this and I have 5 extra gears, 3 47ers and 2 49ers lol, so I'm all set but holy crap this engine is a beast :D The tuned pipe sounds very mean, similar to the ribbed pipe. When I change the gear I think I'm gunna try out the CVEC pipe and see how that goes.

arawak420 said:
i may be mistaken,but dont they start these engines after assembly? test? just like a new car when it is built.
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I don't think they do, and even if they did to get a carbon deposite like that you would have to run quite a few tanks through it.
 
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Can you use a steel spur for the 4.6.....or is using plastic better in order not to tear something else up in the drive train?

My 4.6 should be here anyday now and I thought I had everything I needed...minus a few extra spurs from the sound of it.
 
Well, its got 4-Spider diffs, and heavy duty drive cups all around, and heavy duty dogbones. So I think it would be okay. In my old savage I ran a Wasp .28 with the steel spur and all was fine.
 
I would not run a steel spur. In this case with a steel spur you would have probably ended up stripping one of the plastic gears inside the transmission. A better plan would be to loosen the slipper a bit when driving on a high load surface (like grass, snow, deep dirt).
 
Yeah, thats what I'm gunna try first. But I'm not too worried about the drivetrain, cause my Wasp .28 didn't do anything.

HPI doesn't give any torque ratings that I know of, but its a very torquey engine. They did say 2.9 HP like said by Turbo.
 
TTT

Any more reviews on the 4.6 from anyone? A lot of you guys should be through with break-in stage and starting to let'er rip. Any gremlins surfacing?

I know some have been breaking pull starts but I've read if you loosen up the glo-plug before you start crank'in your more likely NOT to snap/damage your pull start. After it's running tighten the glo-plug back down.

My SS actually shipped today and should be here by the end of the week so I'm getting ancy :dance:
 
I have been womndering if this engine can be modded. ...
 
I'm surprised so many have been breaking pull-starts, this engine doesn't have nearly as much compression as my Wasp .28 has. It still has tons of power but it isn't as tight as others I've had.

I have let her rip, still can't hit second gear, probably cause its like 10 degrees lol.

Jon, any engine can be modded, its just a matter of giving it more performance insted of killing it lol :)
 
AC48 said:
I have let her rip, still can't hit second gear, probably cause its like 10 degrees lol.
Click to expand...

Are you riding on snow? I went out with my brother (Revo) yesterday and he was having a heck of a time getting it into second....riding on snow/ice. We moved to an area with more dirt than snow and it shifted alot earlier from more of a load on the engine I'm thinking. Get it back on the ice and it would just rev it's little heart out in first gear :ponder:
 
Its on tar, which has some snow on it but not much...may need to be adjusted.
 

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