Original Hpi Nitro Rs4

[vwjuice]

My uncle bought this in 1997 to compete against mine and my Dad’s rs4’s. Unfortunately we sold our rs4’s and started running 1/8 buggies. Fast forward to Christmas 2017 and my uncle gave me his old rs4 that he’s kept for so long. There’s a ton of parts to go with it. It will need a full tear down and rebuild, but I can’t wait until summer to get this back on the road.

[XLR8]

Cool! Lots of bits packed into a small space. Does the belt just right of the pinion/spur actually drive the front wheels? Anyway, it looks interesting. Can you post some rebuild pics once you get into it?

PS I think I have one of those Mustang bodies. I think it was by Parma??

[vwjuice]

The belt off the spur assembly goes to a shaft in front of the pinion. On the other side of that shaft is another belt that runs to the front diff.

I will definitely post pics once I get parts coming in. I’m looking for a new chassis, carbon fiber shock towers and upper deck, full bearing kit, etc.

[vwjuice]

Inspecting the car I found it has an of a 2spd kit, but the 2nd gear is missing a couple teeth. Not to worry found new gears on eBay for $12. It also has the front belt tensioner, sway bars, with extras, hpi tunes pipe, and when I removed the cylinder head from the engine the piston it at bdc. The piston and sleeve look good as well, so I’ll take the engine apart and clean it up.

Plans for the car are to get the racer or Hg chassis, carbon fiber top deck, rear brace, and shock towers. Aluminum center belt tensioner, steering bellcranks, lower arm holders front/rear, new servos and battery, rebuild the diffs, new shocks, and possibly aluminum diff bulkheads if I can find them.

Body, wheels, and tires will be easy to get once I decide what I want.

[XLR8]

Yeah, I noticed the missing teeth on that inner spur. Anyway, it's good you were able to find spares. The car should clean up real nice.
I've only owned one nitro car and it was in the '80's and it was nothing worth discussing here. I do know that those little motors can make some serious HP - maybe a lot more power than the tires can handle. Are you able to tune the clutch to function like the slipper in an electric vehicle?
I knew a racer friend bitd who raced 1/8 scale for Delta. He told me that one of his team mates car held the record (Guinness?) for the fastest accelerating piston driven vehicle. Not sure if his claim was valid, I never checked it out. I reckoned that the hp:weight ratio for those cars was pretty incredible.

[vwjuice]

Yeah you can tune the clutches on these by making them engage earlier or later, but that’s about it.

That would be pretty cool to see your friends car. Those 1/8 gas on road cars are crazy fast.

[XLR8]

I agree it would be cool to see that old car again but unfortunately my racer friends and I have not stayed in contact over the years.
When you have your car finished, will you run foams on pavement or are there better choices for tires these days? I haven't run anything on-road in decades. We used to spray the pavement with sugar/water to improve traction. And, depending on where we were, time of year, etc. it would sometimes attract flys. haha.. But, it certainly worked. Sounds dumb, doesn't it. We used to do the strangest things for the sake of racing. Once we used one of the racer's RC helicopters to dry the track after a rain storm. Ah, those were the days.. Ha!

[vwjuice]

I remember the days of sugaring the track.


The tires nowadays are far better than they use to be. I will probably get some foams and some rubber tires. I might try racing it a couple times, but it won’t be anything serious. I will mostly run it around in the street.