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-   -   HPI RS4-3 102mph run! (https://www.rcuniverse.com/forum/rc-road-nitro-cars-242/11156212-hpi-rs4-3-102mph-run.html)

fdjizm 07-15-2012 11:46 AM

HPI RS4-3 102mph run!
 
Awesome runs today! got a vid of the car hitting 102mph finally!
I'm more excited about this than putting the belt drive rs4's into the 100's.
Since it's shaft drive and I haven't seen anybody try this on the rs4-3.
Alot of custom work done on this car! woooohoooo!!

http://i48.tinypic.com/qpo5xg.jpg

[youtube]http://www.youtube.com/watch?v=Jxhk4-HdOWc[/youtube]

the vid is not that exciting lol

Anthoop 07-16-2012 08:29 AM

RE: HPI RS4-3 102mph run!
 
Good job.
What engine/pipe/fuel/gear ratio?

fdjizm 07-16-2012 09:16 AM

RE: HPI RS4-3 102mph run!
 
Thanks!
It's an RBmods novarossi flash 21, 086 ofna pipe, 30% O'donnells speed blend, final gear ratio is in the 2.4's with 65mm 45 shore foam tires.

nastyboys727 07-16-2012 05:13 PM

RE: HPI RS4-3 102mph run!
 
kool beanz one more for team nitro electrics do it easy bla bla bla now doin it with nitro thats true hobby to me

fdjizm 07-16-2012 05:20 PM

RE: HPI RS4-3 102mph run!
 
Couldn't agree more, anybody can pile on batteries!!! :)

Anthoop 07-17-2012 10:56 AM

RE: HPI RS4-3 102mph run!
 
Thanks for the info. ;)
By my calculations the engine is turning at around 33,000 rpm at that speed...did I work that out correctly? It is hard to see from the video but is the engine reaching its peak with that gearing or are you running out of road?

I do not know the RS4 cars but I see you mention this one is shaft drive, can I ask how many teeth on the pinion and spur?

fdjizm 07-17-2012 11:42 AM

RE: HPI RS4-3 102mph run!
 
33k is exactly right and the engine isn't reaching it's peak but I think it's pretty much peaked out versus the load at that speed
I don't hear the rpm keep rising anymore after a certain point.
I don't run out of road, the engine just levels out and maintains speed.

Yes this is the shaft drive RS4-3 EVO SS whatever they want to call it lol.
I like the zero rolling resistance over the belt drive cars plus I haven't seen anyone do this with this particular car.
Going to have to keep the gearing to myself for now, you understand ;)
But it's all custom fit/dremel'd/cut/drilled stuff.
I also had the savage manifold cut and welded to my specs for a nice fit in the chassis and high rpm power.
http://i46.tinypic.com/2n1byqf.jpg

Anthoop 07-18-2012 08:33 AM

RE: HPI RS4-3 102mph run!
 
Have you or are you going to try a different ratio? My thinking is that if the engine is peaking with that ratio then if the ratio was higher the engine may be able to push it to a higher speed. Note that when I am saying "engine peaking with that ratio", I mean that the engine will not pull any more rpm because of the gear ratio (probably not the best way of terming it but you know what I mean now). ;)
I am guessing the engine is good for around 40k?

Oh and no problem about the pinion/spur. ;)

fdjizm 07-18-2012 08:44 AM

RE: HPI RS4-3 102mph run!
 
The engine I am sure is good for around 40k, but yes I can tell you it's not peaking being that it gets up to around 33k only and then levels off.

I can probably gear just a bit to get more RPM, but I think the engine has a much higher survival rate right now being that it isn't exactly screaming it's brains out lol

I have a few possibilities to try, I will probably end up gearing down and making the car fun again instead of needing 500ft+ to play with lol.
I just don't feel comfortable *****g out RPMs on this engine being that it's pretty expensive :)
the way it's geared now it 'stops pulling' around 33k is a pretty safe setup for all the load I am giving it.
The actual gearing is mathematically good for 105 or so but i would need to get to 35k to pull that and I don't see that happening.

I am always willing to help with the car setup if you're trying something like this, just hard to throw out exactly what I've done being that there is alot of work involved and I would have to go into dremel use and shaving this and cutting that to make this fit etc... lol


gearhead777 07-18-2012 03:57 PM

RE: HPI RS4-3 102mph run!
 
That is siiiiick. Nice job man. Been a gear head my whole life with full scale stuff, and as my profession. Just got started in rc road cars, have been reading all the threads that I can find, so I'm thinking of starting a project myself. Being a nito only guy, this shall be fun. I will be looking you up for advice as it moves forward.

Anthoop 07-19-2012 09:46 AM

RE: HPI RS4-3 102mph run!
 


ORIGINAL: fdjizm

The engine I am sure is good for around 40k, but yes I can tell you it's not peaking being that it gets up to around 33k only and then levels off.

I can probably gear just a bit to get more RPM, but I think the engine has a much higher survival rate right now being that it isn't exactly screaming it's brains out lol

I have a few possibilities to try, I will probably end up gearing down and making the car fun again instead of needing 500ft+ to play with lol.
I just don't feel comfortable *****g out RPMs on this engine being that it's pretty expensive :)
the way it's geared now it 'stops pulling' around 33k is a pretty safe setup for all the load I am giving it.
The actual gearing is mathematically good for 105 or so but i would need to get to 35k to pull that and I don't see that happening.

I am always willing to help with the car setup if you're trying something like this, just hard to throw out exactly what I've done being that there is alot of work involved and I would have to go into dremel use and shaving this and cutting that to make this fit etc... lol


I think you should use the engine to it's potential, after all you paid a lot of money for an engine with that potential. :D
Just my opinion of course.
Thank you for the offer of help, I will shout if I need advice. ;)

fdjizm 07-19-2012 09:56 AM

RE: HPI RS4-3 102mph run!
 
I can throw a bigger spur on it and see how high she revs, and I probably will, just have to order an extra con rod just in case lol.
took a quick pick of how it currently sits, made a new top plate for the center out of some 3mm CF.
http://i47.tinypic.com/jq6ewx.jpg
http://i47.tinypic.com/2ur6o2e.jpg

miniphsyco 08-01-2012 11:27 AM

RE: HPI RS4-3 102mph run!
 
man do you work at a CF factory lols i have just got some CF sheeting id love some CF parts but hardly any for the thunder tiger VX 18. pro :S 


fdjizm 08-02-2012 02:55 AM

RE: HPI RS4-3 102mph run!
 
I just bought a 3mm sheet of ready done CF off ebay. I have spare pieces left off from the chassis I can make shock towers with etc...
All I have is a dremel, drill and a bunch of bits/sanding drums etc.. you can make them yourself out of the sheet just make a template. :)

miniphsyco 08-02-2012 09:23 AM

RE: HPI RS4-3 102mph run!
 
thanks for info man greatly appreciated :D  how much did u pay ???


miniphsyco 08-02-2012 09:25 AM

RE: HPI RS4-3 102mph run!
 
http://www.ebay.co.uk/itm/3mm-ABS-Ca...item35beb51e39 ???

Anthoop 08-03-2012 01:54 AM

RE: HPI RS4-3 102mph run!
 

That is not carbon fibre.
http://www.ebay.co.uk/itm/Carbon-Fib...item4ab82fe383

fdjizm 08-03-2012 05:08 AM

RE: HPI RS4-3 102mph run!
 
This is the sheet I bought...

http://www.ebay.com/itm/Carbon-Fiber...item2560b3b9a6

It's 3mm thick 9" x 12".

I don't have too much left over after cutting out the chassis, but enough to make stuff like shock towers and a top plate for the center.

miniphsyco 08-03-2012 12:57 PM

RE: HPI RS4-3 102mph run!
 
what country do you live in ?


miniphsyco 08-03-2012 01:05 PM

RE: HPI RS4-3 102mph run!
 
can you post pics of ur car after all carbon fibre has been done ??

JohnP2 08-03-2012 04:25 PM

RE: HPI RS4-3 102mph run!
 
Go NITRO! :D

fdjizm 08-03-2012 04:51 PM

RE: HPI RS4-3 102mph run!
 
Mini, I'm in the U.S, new jersey.
I have pics of the chassis in another thread, didn't actually use it yet ironing some things out with the car still.
The CF chassis is not a good idea for just driving around testing the engine will most likely overheat. (worse than it does already lol)

miniphsyco 08-08-2012 04:23 AM

RE: HPI RS4-3 102mph run!
 
hahaha mate i live in England and in Cleveland do you ever use a shell? if u cut out a hole in the front bumper and make a grill that is what im doing with mine it keeps it cool

fdjizm 08-08-2012 05:12 AM

RE: HPI RS4-3 102mph run!
 
I've had much better luck without the body as much as i'm risking damage it just doesn't lift.
I do want to run a body it looks much nicer!

laralist123 09-19-2012 11:06 PM

RE: HPI RS4-3 102mph run!
 


ORIGINAL: fdjizm

I can throw a bigger spur on it and see how high she revs, and I probably will, just have to order an extra con rod just in case lol.
took a quick pick of how it currently sits, made a new top plate for the center out of some 3mm CF.
http://i47.tinypic.com/jq6ewx.jpg
http://i47.tinypic.com/2ur6o2e.jpg
Good work done.This speed is awesome.You share some good pictures.Can you explain more about its parts and performance.??http://washington.craigslistb.org


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