Restoration Project #8 - Huge Bundle of HPI, Kyosho and HSP.

[tudordewolf]

Too late for me now to see if the pin is in there?

You can probably spot it through the chassis, here's an angle on mine, you can see the "glint" of it.

If you look closely, you'll see that the gears are toast from knocking the mesh out of alignment in a cartwheel.

 

[gandalfnz]

Wow, what did you do to your spur gears, rocks stuck in there?
Maybe put a tape over that opening.

It just shifted into second, so it works. Woohoo!

 

[gandalfnz]

Wow, just wow.
Again, this engine proves to be so easy to break in and tune.
After idling for 4 tanks at 100C, I ran it rich for another two and then tuned for performance.
The engine just purrs and idles so well.
Does not have the take off like the RS4's, but its almost there.
Temp is always around 90C, which is awesome.
I would recommend HSP to anyone.

Cheers

 

[gandalfnz]

And the final restoration of HSP flying fish is complete.
New engine broken in and ready to annoy the neighbors.

Need to buy more, nothing to restore atm.....

 

[tudordewolf]

Fixed up those gears and finally got some good speed runs recorded. 42mph with the body, it loses 1mph compared to no body. 3.6 seconds to 42mph, .6g acceleration all through 1st gear, which suggest that the later it engages, the better.

Also, this is the beauty of that GPS:

 

[gandalfnz]

Thats fast!
Is that a VX18 and 18/23 clutch bell?

 

[tudordewolf]

Is that a VX18 and 18/23 clutch bell?

It is! And Torco 30% nitro, though I hit similar speeds with sidewinder 20%. The Torco runs cooler and its exhaust smells crispier, also leaves a cleaner smelling oil instead of the mildly rancid smell of castor.

 

[gandalfnz]

The only way to the next level is engine upgrade?
I guess this is decent for a VX18.
Transfer the 3.3 to that f fish and see it take off from the ground?

 

[tudordewolf]

The only way to the next level is engine upgrade?
I guess this is decent for a VX18.

That's hitting ~28k RPM and the falloff in acceleration tells you it doesn't have much torque past that.

There's still those locked diffs with the lower ratio, potential to be about 1.4x faster, assuming the car tracks alright with all 4 wheels locked together. Should be ok in a straight line, and that opens up the potential for 55+mph... I'm tempted to throw them in right now and see how it does tomorrow.

Could also try "modding" the VX18 sleeve or crank for some extra flow. I have half a mind to given the number of them I've got lying around now...

I'll also follow up with runs of my Evo-12 equipped fish, that was faster even on stock gearing. I haven't given it an 18/23 yet, just to have the widest variety of configurations between cars.

 

[gandalfnz]

Could also try "modding" the VX18 sleeve or crank for some extra flow. I have half a mind to given the number of them I've got lying around now...

Put the the 3.3 on….

How do you mod the sleeve?

 

[tudordewolf]

Put the the 3.3 on….

How do you mod the sleeve?

Tempting indeed. I'm not crazy about wrecking $250+ of engine if/when I flip it at 50+ in an onroad. At least in a truck it has some crumple zone around it. The Evo-12 was $90 and I sorta hoarded a bunch of them...

Proceed at your own risk, a classic post from this very forum. I haven't attempted it yet myself. Definitely something to learn on a junk engine. Nicer engines have some of that finishing already done, hence the term "factory modded"

 

[Chubaka]

Tempting indeed. I'm not crazy about wrecking $250+ of engine if/when I flip it at 50+ in an onroad. At least in a truck it has some crumple zone around it. The Evo-12 was $90 and I sorta hoarded a bunch of them...

Proceed at your own risk, a classic post from this very forum. I haven't attempted it yet myself. Definitely something to learn on a junk engine. Nicer engines have some of that finishing already done, hence the term "factory modded"


View attachment 151958

Nice collection. I done that mod to an old Traxxas Trx Pro .15. I wouldnt mind another in the future.

Really woke that lil mill up.

Congrats on the speed. Car looks like its bookin.

 

[tudordewolf]

Nice collection. I done that mod to an old Traxxas Trx Pro .15. I wouldnt mind another in the future.

Really woke that lil mill up.

Congrats on the speed. Car looks like its bookin.

Thanks! Would you say to do exactly as the guide suggests? I've got more or less exactly the tools pictured, I'll probably be using grinding bits all the way instead of any milling bits...

 

[gandalfnz]

Thanks! Would you say to do exactly as the guide suggests? I've got more or less exactly the tools pictured, I'll probably be using grinding bits all the way instead of any milling bits...

I guess this will affect the engines fuel consumption and also shorten its lifespan to some degree....
Def interesting to see the performance increase....
Cmon mate, you got too many engines to spare.....

 

[gandalfnz]

I did a bit of experimenting today with my busted VX18 sleeve.
As you can see, did a pretty good job of the boost port, then experimented with different types of dremel bits on the intake ports.

I am not sure why they ANGLE the grooves into the intake ports, because the channels in the crank case are totally vertical, and in the guide above, he says to follow the direction of the channel in the crank case?

This literally took 10 mins to do...

Any feedback guys?
Cheers

 

[tudordewolf]

Nice! How's it run?

I am not sure why they ANGLE the grooves into the intake ports

I think they're trying to increase this effect, known as Schneurle porting:
:

That's the top view, but also consider it in 3D- the piston has most of its volume above the ports, you want to push the fresh fuel/air mixture "up" into that space

Also, while you've got the crankcase out, can you verify an observation for me? It looks like they only mill channels for the "transfer" ports adjacent to the exhaust port; there's no channel for the 'intake' across from the exhaust.

It might not use the intake port at all, making the "fangs" on the transfer ports even more important. Also, it looks like milling out a little more from the bottom of the channel to the left of the exhaust port could improve gas flow through the engine.

 

[gandalfnz]

Not sure here...

I was under the impression that those two are the intake ports, where the fuel gets sucked in? Because, these are the ports that get the "groove" cut into, to allow more fuel to enter this way? Is this not the case?

Always wanted to figure out how the ports actually work and what each one is for, maybe now is the time.

I have not tried to run this, as the piston I took photos of is a busted one, and I only did it for practice.

 

[Chubaka]

Thanks! Would you say to do exactly as the guide suggests? I've got more or less exactly the tools pictured, I'll probably be using grinding bits all the way instead of any milling bits...

I followed some of this one, and another one years ago when traxxas had monster.traxxas as the forums compared to the new forums.traxxas, someone had a write up that I followed. The main rule is dont grind a hole all the way through. I did this on an engine on its way out that was going to be sent to traxxas.

I can't find it now, I may have a hard copy printed. I also cleaned up my crankshaft also to help it match.

 

[tudordewolf]

Not sure here...

I was under the impression that those two are the intake ports, where the fuel gets sucked in? Because, these are the ports that get the "groove" cut into, to allow more fuel to enter this way? Is this not the case?

Always wanted to figure out how the ports actually work and what each one is for, maybe now is the time.

I have not tried to run this, as the piston I took photos of is a busted one, and I only did it for practice.

Sorry, "transfer" port was confusing which is why I put it in quotes; everything other than the exhaust port is an intake port in the sense that fuel/air mixture flows into the piston through them, and only leaves via the exhaust port.

"boost ports" and "transfer ports" are just extra intakes shaped to try and maximize the replacement of exhaust with fresh mixture. At least, this is my understanding. If I am wrong I am eager to learn their correct function.

We call the port opposite the exhaust port the intake, and the ones adjacent to it transfer ports, and then even more of them are called "boost" ports, but they're all moving fuel-air mixture from the crankcase volume to the piston.

The sleeve fits snugly into the crankcase; anywhere that isn't milled out to meet a port will be blocked. In the VX-18, it looks like the "intake" port is closed off completely by the cylinder block.

Unless they've figured out some crazy fluid dynamics where having that little "cave" improves scavenging, as its called, I think it may be a bit of an abandoned design choice they left in.

There's lots of vague information out there, I'm sure I've oversimplified some highly nuanced developments in 2-stroke technology.

http://twostrokehistoryplus.jigsy.com/loop-scavenging-and-boost-ports

 

[gandalfnz]

Sorry, "transfer" port was confusing which is why I put it in quotes; everything other than the exhaust port is an intake port in the sense that fuel/air mixture flows into the piston through them, and only leaves via the exhaust port.

"boost ports" and "transfer ports" are just extra intakes shaped to try and maximize the replacement of exhaust with fresh mixture. At least, this is my understanding. If I am wrong I am eager to learn their correct function.

We call the port opposite the exhaust port the intake, and the ones adjacent to it transfer ports, and then even more of them are called "boost" ports, but they're all moving fuel-air mixture from the crankcase volume to the piston.

The sleeve fits snugly into the crankcase; anywhere that isn't milled out to meet a port will be blocked. In the VX-18, it looks like the "intake" port is closed off completely by the cylinder block.

Unless they've figured out some crazy fluid dynamics where having that little "cave" improves scavenging, as its called, I think it may be a bit of an abandoned design choice they left in.

There's lots of vague information out there, I'm sure I've oversimplified some highly nuanced developments in 2-stroke technology.

http://twostrokehistoryplus.jigsy.com/loop-scavenging-and-boost-ports

Gonna put this on hold for now, as I just acquired another big bundle of nitros, so will be busy with that.
VX18 for met at least is def sluggish, but I think it might get better as it breaks in further.