MPH Challenge

[Nitronaught]

Yeah, Snook, I forgot to post the link, but it was Rivermaxx's post I was referring to previously....

Looks cool..... Multiple motors? AH, I knew this design was too simple and you had to step it up a notch..... Are you sure you wanna do that? loll

[Snook Man]

I will only use 2 if I need more torque
But I do like the option of being able to run it either way (single or twin).

[spencer_lee1993]

Engine/ Carb intake

[Snook Man]

I don’t think getting sufficient air to the filter will be a problem but I may be wrong
If I tailor the chassis with CF panels to match the outline of the lower body to button it up as much as possible air flow may be a factor. I will definitely need something to help support the body sides from flexing inward when up to speed. I can already see them flex with just the leaf blower.
I will just wait and see what happens when I get it up and running. If I lower the body much more than it is the air filter will have to be on the outside because the body will be too close to the top of the carb anyway.

[spencer_lee1993]

I wonder if you could cut out part of the body, fill it in with air filter material and build a hose or some type of tubing to direct the air into the carb, that is what they use on real race cars because the intakes are not always in the best of spots. By using this it would still keep the filter at the same level as the rest of the body, but make sure it is sealed up good so that the air docent catch the inside of the body and generate more drag. I think that with your current body design, the engine would deffinetly not get very much air.

[1979chevy.]

I don’t think getting sufficient air to the filter will be a problem but I may be wrong

Yes, you shouldn't have any problem with it, it's not like that body's airtight.
What if you cut two strips of whatever you made the body out of haha, bend them into a bow shape and attach them to the sides of the chassis?

But what I'm I saying, you probably have a much better idea already haha.
Looking great man



God answers prayer,pray,believe,NEVER GIVE UP!!!

[nitro on fire]

how about a make shift air scoop in the front of the body where it comes to a point and a rear exit for caught unused air so the it doesnt want to flip onto its shell

[morganko]

John Force would be proud!

[08kgraves]

i think your probly right about that one!

any more progress?

[BadMilkMan]

I cannot wait to see the final product. Snook, you are crazy! I would never be able to do this!!! I hope this works, the I can prove to my friend that Nitro is better the Electric!

[BadMilkMan]

If you did a dual engine (which would be AWESOME), keep in mind that when you hit 3rd gear, its gonna be hard to stop. In your picture, I didn't see a braking system, I know you probably know that, but I would put a vented disk brake on there.

[Snook Man]

I’ve been out of town working for the past few days so I haven’t made any progress. But I did come up with a different design of triple idler gears between the clutch bell and spur to change the input direction of the spur back to the standard rotation. It works well on paper I’ll just have to see if I can make it work like I think it can.
I have some pretty decent brake setups that should work well, If not I could always add a parachute for a little authenticity

[ross93]

looks cool (along with your last project buggy), cant wait till you run it!

[08kgraves]

being that your going to just make single passes a parachute wouldnt be bad idea. probly a little to impractical for an rc car though cus u have to have a way to launch it as well.

[Wildman4910]

being that your going to just make single passes a parachute wouldnt be bad idea. probly a little to impractical for an rc car though cus u have to have a way to launch it as well.

You put a spring in the parachute pack just like they do on full scale drag cars.

[08kgraves]

ok so what are you going to do then run like 500 ft of string so you can yank it when u want to deploy the parachute? lol

[1979chevy.]

ok so what are you going to do then run like 500 ft of string so you can yank it when u want to deploy the parachute? lol

That's what the extra servo is for haha



God answers prayer,pray,believe,NEVER GIVE UP!!!

[1979chevy.]

@graves, but I agree with you on the fact that it is really not that practical, because I imagine he is going to be making several passes and messing with that chute would be a pain.




God answers prayer,pray,believe,NEVER GIVE UP!!!

[08kgraves]

but why add an extra servo if hes trying to make it as light as possible for a high speed run?

the proper answer would be to attach the string to the throttle/brake servo like normal lol.

[Snook Man]

I think just a set of brakes alone will be plenty to slow the rig down.
Being only 2WD I will just have to adjust them so that they do not lock-up (like all 2WD’s tend to do) and flat spot the tires or loose control and crash.

If I were to use a chute; a micro servo, linkage and cute box could be made small enough to add only a few oz’s but I doubt I will go that far (KISS).

[stallion 63]

Hi Snook,I've a half built dragster lying around for nearly 2 years now.Partly because I couldn't find anyone to fabricate a tube rail or cnc alum for the front.So far I've the kyosho 8.5 buggy drive shafts,a 2 speed kyosho CD and 40 series road rage tires mounted on pan chassis for the rear end.
I couldn't decide on the engine though.Should I go for higher rpm 21s or more bottom end BBs?

P.S. I'm not planning to do 100 mph in this build.

[Snook Man]

I couldn't decide on the engine though.Should I go for higher rpm 21s or more bottom end BBs?

Would depend on the weight of the rig… If it’s light weight, go for higher rpms. If too heavy for the smaller displacement to pull the gears you want to run then go for the BB.

[Snook Man]

So after pondering my triple idler gear idea for a few days I mocked it up to see how difficult it would be.

It’s basically just 2 plates, 3 gears and 3 shafts.
1 plate will mount to the transmission mounts and will also have screws up through the chassis into the plate. The other plate will be connected through the chassis with screws and there will be 2 bars attached connecting both plates at the cut angles.
The shafts will be custom made to fit spur gears with center bearings with the ends reduced in diameter to fit the hole in the plates.

Once I round up some 5mm aluminum and the correct size spurs (width and tooth count) it should make for a pretty compact way to mount the engine(s) at chassis height and still mesh with the smaller diameter slipper clutch spur needed for the correct gear ratio.

It will also open up a lot of possibilities when mounting the TMaxx transmission on a pan type chassis.
It’s not pretty (yet) but the mockup worked out better than I thought it would.
Its amazing what you can do with a big box full of gears.









I think I will end up building 2 different versions, 1 for twin engines and 1 for a single engine that both will allow for 4WD.

[stallion 63]

Hi snook,interesting idea!what rpm are you trying to reach with this set up at the driveshaft?

[Snook Man]

I’ve never calculated the drive shaft rpms but, 3rd gear is very close to a 1:1 ratio, SG/CB ratio will be approx 2:1.
So at 30K engine rpms the center drive shaft should be turning around 15K. That is until it pops out!

[stallion 63]

Are you any closer to the 100 mph target with this set up?Can't wait to see this baby run!

[Snook Man]

I have no idea yet... I wont be running it until this spring most likely. It will take a while to cut the chassis and make everything until the 1st run.

[kvg20]

Hey snook I know this is off topic but I'm looking for a aftermarket manifold to go on my 4910 with a 3.3. I have the resonator pipe but i dont like the stock manifold. Also I wanted to up grade my carb to a bigger one but I dont want to break the bank. Would you have any suggestions for me. Thanks

[Snook Man]

There are not a lot of options for headers for the 3.3 engine, and even less when its used on the TMaxx.

I don’t see/get much advantage or performance gains with a bigger carb on the 3.3 so I stick with the stock carb on the 2.5/3.3.

[stallion 63]

There's really no need to change the header on either the 2.5 or the 3.3.The stock headers are quite sufficient especially when coupled with a resonator pipe.These are about the most you can do on these engines.Unless you want a BB carb mod.Again,only if you've stripped the HSN.Then you can consider an alum bb carb.And no,you won't break the bank for this.Costs just as much as the stock ones do.Just make sure whichever carb you get fits your engine.Not all do.

[lubecakes]

Hey snook I know this is off topic but I'm looking for a aftermarket manifold to go on my 4910 with a 3.3. I have the resonator pipe but i dont like the stock manifold. Also I wanted to up grade my carb to a bigger one but I dont want to break the bank. Would you have any suggestions for me. Thanks

The best carb upgrade for a 3.3 would be the OS 11k, but it only helps in tuning. THS makes a very nice pipe and manifold system that will wake up your trx engine all by itself.

[revomatic27]

looking great. anymore progress

[kvg20]

The best carb upgrade for a 3.3 would be the OS 11k, but it only helps in tuning. THS makes a very nice pipe and manifold system that will wake up your trx engine all by itself.

I've been looking at THS manifold , but i want to keep the resonator pipe. they make two manifold . One i would have to heat up and bend to match the angle of the resonator. They also make another one that is used with there angled pipe. I just dont know if it will be long enuff to mate up with my pipe. I'll check out that Os 11 . More Air + Fuel =More POWER!

https://www.sitegidget.com/itechapp/...manifolds.html

https://www.sitegidget.com/itechapp/...manifolds.html

[Snook Man]

No real progress, just making a few different templates to determine how I want to cut the chassis plate(s) and see which layout will be best suited.

I want to be able to use the same plate for both a single or twin engine setup.
The main (center) chassis will be aluminum with optional CF plates that I can add to it to extend out to the body line.

[1979chevy.]

Ok, nice.
But what have you done to your chevrons man?
Does cutting them like that help that much? I'm guessing you did that for better traction on a track or something.



God answers prayer,pray,believe,NEVER GIVE UP!!!

[davidemaxx]

i have a suggestion
maybe a scoop?

[maximus9]

hey snook i just saw a custom drag chassis on sale
http://www.rctech.net/forum/r-c-item...look-here.html

maybe it may help in ur build

[Snook Man]

Thanks for the link maximus9 but my chassis will be more than twice the length of that one.
He also wants way too much for that piece of aluminum

[08kgraves]

looking good snook

[davidemaxx]

No real progress, just making a few different templates to determine how I want to cut the chassis plate(s) and see which layout will be best suited.

I want to be able to use the same plate for both a single or twin engine setup.
The main (center) chassis will be aluminum with optional CF plates that I can add to it to extend out to the body line.

are you going to use exhaust deflectors with this project?