TTR EK4 S2 Project BEAST MODE

[twintec99]

Thank you all for comments and data. My clutch broke also and I'm wondering if it is because of that locking differential. I was testing and tuning and the front wheel locked up and noticed that pin stuck into the wheel cup. What a horrible design. Is there a different drive shaft I should be using, or do they all have that locking pin on the end, susceptible to coming out?

I had the old style clutch that was a clamshell with msj flywheel. All the clutches I see now are two or three pin and work like slipper clutches. So that MSG flywheel is pretty much worthless now? If I'm correct, I need to go to a two or three pin flywheel. This motor has so much power, I don't think it really matters what material clutch I use. Any suggestions would be helpful. I see many aluminum type clutch shoes on eBay. I also believe my old clutch was part of tuning problem.

If one wanted to build this Rc dyno, exact dimensions. 20.25" wide, 23.25" long, 5.5" tall, then 4 rollers are mounted 2" above drawer. Rollers are 1.38" or 35 mm diameter. Rollers tip to spring loaded shaft tip, 21.5", roller itself is 19.5" long. First roller to rear 4th roller is 16 5/8" center to center. 2nd roller and 3rd roller are 4.25" apart from 1st and 4th roller. Obviously tire diameter will affect roller distance. EK4 stock tires are 6.25" tall.

I have attached some pictures of the Rc Dyno as requested, not really a dynomometer, just rollers. The rollers look very similar to what would be on some type of assembly line. They have spring loaded tips so you can adjust the distance in between. It also has a nice drawer to put all your rc goodies in. No name of any kind or logo. One could make something similar. It works very well for testing, as you can see the smoke change, and see/ hear the power change in motor. Adjustments can be done with self holding the truck and one hand on transmitter, however two people would be ideal. One could get 2 small gauge chains and attach to the rear chassis so it doesn't move. The stock bungees were worthless.

One more question, is that 3 ch FlySky GT3B radio I see everywhere decent? I know it's cheap, but almost everything now is made in China, and then prices are jacked up with companies Branding.

Its Murphy's Law: RC's only lose signal at full throttle. Sorry to hear about your rig. Look on ebay for your parts first. If you can't find parts specific to EK4, look for
EB4 S2 suspension parts. They're identical. In the meantime ill try to dig up part numbers.

The front of the chassis is supposed to have a slight bend like that.

NT, Thank you. I know you went through a complete rebuild. Didnt you change the drive shafts and if so, do they still have locking pins susceptible to coming out and locking up the wheels. Maybe you can give me the part you ordered for your front/ rear drive shafts, and if you did change them, and if they will work with my EK4 front diff and MSJ rear diff. Thanks. I'm sure you could tell me what I need to change, and what could stay stock. I'd hate to put more time into this, only to learn 3 steps from now I should have changed another part first . So any advice you have is appreciated. Even if you think I should get a completely different rig that is more modern and not susceptible to break, or if I I can just modify this one. Thanks!

View attachment 17824 View attachment 17823 I dug up some old info I had. This is how mine is set up. Damn can't get the bottom page on top. Lol. Read the bottom page first. I hope this helps.

Try this


Iv had the same problem with FM futaba radios. I have a spring attached to the servo horn that pulls the servo horn to close the throttle if the radio dies. Sorry about your wreck.
That dyno looks way cool. How does it work? More pics! I'd like to see how it works.
Thanks

 

[twintec99]

I also decided to relocate fuel tip as suggested further down pipe. Attached are some pics of the original schematic of the ek4. If anybody needs any close-ups, let me know. Unfortunately there are no part numbers associated with the schematic.

 

[Certified Mike]

Absolutely awesome! You guys are Def an inspiration! I am actually restoring an old associated car. I am in no hurry so making a thread about it wouldn't work out so good but yeah, I love all the info and the fails and fixes.

 

[Nitrotrout]

Absolutely awesome! You guys are Def an inspiration! I am actually restoring an old associated car. I am in no hurry so making a thread about it wouldn't work out so good but yeah, I love all the info and the fails and fixes.

Thanks for the kind words Mike. I love restoration projects of any kind. The older the better with lots of pics. I'd like to see a pictorial of your project no matter how long it takes. I've learned a lot of facts from others about my particular project car just by being on the internet.

 

[Certified Mike]

I enjoy sharing the knowledge I have and helping ppl out where I can. Its been very satisfying to see other ppl reach their goals with our collective help. The ppl here have Def helped steer me in good directions as well. The internet is great for info, esp with the more rare or outdated stuff that I'm messing with for sure! This site, the ppl here are great and I'm really glad I found it! I have started taking pics of the RC10gt project. I think ppl will get a kick out of it. (The condition I received it in etc...) The only reason I know it was run in this condition is because I am friends with the previous owner. How he ever managed to race this thing is completely beyond me! I will start posting after I get the rest of the parts I need. (I have a Revo I am going to wrap up before this one gets underway as well)
Again, thanks for the inspiration. It's nice to know I'm not the only one willing to get into a full resto project just to be able to say I did it and to rescue a kit that I've always wanted to run.
Like my 1:1 resto of many years ago... Its a labor of love (and insanity, maybe obsession too) Def looking forward to seeing more of your work here too!

 

[twintec99]

I enjoy sharing the knowledge I have and helping ppl out where I can. Its been very satisfying to see other ppl reach their goals with our collective help. The ppl here have Def helped steer me in good directions as well. The internet is great for info, esp with the more rare or outdated stuff that I'm messing with for sure! This site, the ppl here are great and I'm really glad I found it! I have started taking pics of the RC10gt project. I think ppl will get a kick out of it. (The condition I received it in etc...) The only reason I know it was run in this condition is because I am friends with the previous owner. How he ever managed to race this thing is completely beyond me! I will start posting after I get the rest of the parts I need. (I have a Revo I am going to wrap up before this one gets underway as well)
Again, thanks for the inspiration. It's nice to know I'm not the only one willing to get into a full resto project just to be able to say I did it and to rescue a kit that I've always wanted to run.
Like my 1:1 resto of many years ago... Its a labor of love (and insanity, maybe obsession too) Def looking forward to seeing more of your work here too!

Good luck Mike!

 

[Certified Mike]

Thanks! I think I'm gonna need it!

 

[_sOnGoKu_]

WAUU! So if big words friend, my congratulations

 

[Nitrotrout]

You like the "before" pic? HaHa! Thanks for the comment and welcome to RCNT!

 

[_sOnGoKu_]

thanks fot the welcome!
the true,, all are amazing,, hope one day have one like this.

 

[Chevy-SS]

Awesome thread. Glad to see there is still some interest in the mighty EK-4. I have a few of them (3) and I was running one of them today. I almost sold them all, but glad I didn't. These particular trucks really are mean and nasty, LOL. They have much more 'soul' than your average monster truck.

 

[Chevy-SS]

My primary EK4 has the MSJ 2-speed tranny, it's a really sweet rig. Gotta study up on my tuning for it, cause that 3-needle carb is a PITA, haha. My stock fiber clutch blew apart, so I've been trying a few different clutch setups, almost got it. I hate to use metal clutch because the MSJ 2-speed clutch bell is a one-off piece that I probably will never find again, and metal clutch shoes leave a lot of debris that gets ground into the clutch bell. I remember when the EK-4 first came out, there were tons of aftermarket parts available for it. It really hit a sweet spot for a lot of monster truck aficionados, but the glory faded fast. I'm gonna see if I can get someone to video the truck after I get it all dialed in. It will wheelie when it hits 2nd gear, which I always thought was pretty cool.

NT, man you got that pipe looking way better than new! That's a real fine job of polishing that baby up. It does justice to the big heli engine. Nice work, exceptionally nice work........

-

 

[pitbull14218]

I'd love to see a video of it wheeling when it bangs 2nd!

Pretty cool truck, I don't know why they don't use piston rings in more of these nitro engines!

 

[Certified Mike]

They don't use rings in a lot of them becaus3 in the higher rpm nitro motors, the rpms would blow the rings apart. Also, with the high compressions and the extremely tight tolerances with the porting and timing in the design of the sleeve, it becomes an issue with the air/fuel flow inside the motor itself.
Killer work on these rigs!!! I wasn't familiar with these trucks until this post. I obviously missed the boat! I would love to own one!!!

 

[cambodanblacksnake]

I got one for $100 off a mate, the motor was locked up with black tar like crap! cluch bell fibers were swollen on the shoes, I just pulled it apart and made it work! only payed for new fuel and it wheelys like a self employed boss!

 

[Certified Mike]

Sounds like a killer score!!! I catch myself looking every once in a while but I get over it quickly. I have a couple projects that are gonna use up the time and money that is available right now. After I get these going, and a few other things I have going on wrapped up, I'll think about it. (of course, i won't pass up a deal like yours either!) Until then tho, I'll just have to keep drooling over this thread!!!

 

[Nitrotrout]

My primary EK4 has the MSJ 2-speed tranny, it's a really sweet rig. Gotta study up on my tuning for it, cause that 3-needle carb is a PITA, haha. My stock fiber clutch blew apart, so I've been trying a few different clutch setups, almost got it. I hate to use metal clutch because the MSJ 2-speed clutch bell is a one-off piece that I probably will never find again, and metal clutch shoes leave a lot of debris that gets ground into the clutch bell. I remember when the EK-4 first came out, there were tons of aftermarket parts available for it. It really hit a sweet spot for a lot of monster truck aficionados, but the glory faded fast. I'm gonna see if I can get someone to video the truck after I get it all dialed in. It will wheelie when it hits 2nd gear, which I always thought was pretty cool.
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I don't think I've ever seen a MSJ 2 speed. Sounds like a cool upgrade though. Those MSJ parts are like gold, very hard to find these days.
I buy up all the MSJ parts I can find when they come available on ebay. I once got into a bidding war for a complete, unopened MSJ upgrade kit and I tapped out at $400.00. I could have bought an entire car for that.

Somewhere lost in this thread, one of the members posted the factory tuning guide and fuel recommendations. I'll look around and repost it.
As a rule of thumb I think TTR recommends you don't adjust the mid range needle (Which makes no sense, why have a third needle if you can't fiddle with it?)

As far as clutch shoes go....is your 2 spd. clutch bell large diameter like the stock clutch bell? If so, you may have some trouble locating replacement composite shoes.
I may be able to dig up a part # for the slider shoes and narrow the search.
Big and bad as they are, I think the early demise of these trucks was a combination of design flaws and a hefty price tag for back in the day. So all the goodies dried up with it.
That said, we're up to almost 10,000 views on this thread so I guess the interest in these trucks is still there.

As for the polished pipe and top of the cooling head, I think I sanded them down with 1500 grit sandpaper and polished with metal polish.

They don't use rings in a lot of them becaus3 in the higher rpm nitro motors, the rpms would blow the rings apart. Also, with the high compressions and the extremely tight tolerances with the porting and timing in the design of the sleeve, it becomes an issue with the air/fuel flow inside the motor itself.

Mike you're absolutely right about the rings. I think the maximum RPMs of these engines is 18,000, compared to 30,000 to 40,000 RPMs for a tapered sleeve engine .

I got one for $100 off a mate, the motor was locked up with black tar like crap! cluch bell fibers were swollen on the shoes, I just pulled it apart and made it work! only payed for new fuel and it wheelys like a self employed boss!

That's a ridiculous score, congrats! What kind of fuel are you using if you don't mind me asking?

 

[cbaker65]

A heavy duty truck may need heavy duty parts!....That was probably their down fall!

Too bad they can't bring this truck back with some good upgrades ,it is truly a bad a$$!...

I remember it in the early years in the rc magizines an drooled over it!...

 

[Nitrotrout]

A heavy duty truck may need heavy duty parts!....That was probably their down fall!

The EK-4 truck is basically a EB-4 1/8 scale buggy with monster truck wheels and tires, and a .70 helicopter engine. So you're right, parts failures such as the diffs were a problem
There was also design issues. Overheating with the compact helicopter cooling head, There was also tuning issues due to poor design of the exhaust pipe. The return nipple was located directly above the exhaust stinger in the first models, The carbon clutch shoes were also an issue, they couldn't handle the torque these engines produce.

 

[sv250]

My primary EK4 has the MSJ 2-speed tranny, it's a really sweet rig. Gotta study up on my tuning for it, cause that 3-needle carb is a PITA, haha. My stock fiber clutch blew apart, so I've been trying a few different clutch setups, almost got it. I hate to use metal clutch because the MSJ 2-speed clutch bell is a one-off piece that I probably will never find again, and metal clutch shoes leave a lot of debris that gets ground into the clutch bell. I remember when the EK-4 first came out, there were tons of aftermarket parts available for it. It really hit a sweet spot for a lot of monster truck aficionados, but the glory faded fast. I'm gonna see if I can get someone to video the truck after I get it all dialed in. It will wheelie when it hits 2nd gear, which I always thought was pretty cool.

NT, man you got that pipe looking way better than new! That's a real fine job of polishing that baby up. It does justice to the big heli engine. Nice work, exceptionally nice work........

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The dtock carb is a pita. An os carb fits and works a lot better. I was running one from an os28