JP's HPi stable

[JpSonoma]

I forgot there was a rally section on this forum, so I just spent the better part of the afternoon reading and admiring everyones rally cars.

I'm really liking the XV01's, there might be one of those in my future.

But for now I thought I'd show both of my HPI rallys:
One is a nitro RS4 3 that I converted to rally
The other is an electric RS4 rally that I'm currently in the process of refurbishing.

RS4 rally:
graphite upper deck
graphite front and rear shock towers (not sure what brand the rear is)
heatsink motor plate
graphite belt tensioner
Novak 21.5 W/ tekin RS





I've replaced all the ball cups with captured ball ends, and I always hated that wire that connects the steering bellcranks. My solution was some low profile ones that just barely clear the front bulkhead.


Also made a little modification to the tensioner to raise the belt up and clear my lipo batteries.


Team bluegroove inner body set.


Even though this car is electric it's not 190mm wide, it's actually 200mm, so a tamiya body is not going to get the job done. Decided to go with HPi's Focus RS.


I've had some Martini decals left over from another HPi body and decided to give that livery a shot on the newer focus.



My other rally is my RS4 3 that I've had forever and was actually my very first RC in this hobby. I bought the original Type SS kit and that was the start of my RC obsession.

The parts list is quite long on this one so I'll keep it basic:
OS .18 cvr
CVD's
Front and rear shock towers from the Super Nitro Rally
Single speed slipper clutch from the original Hpi MT
Two speed clutch bell, but I only use one gear. I found the two speed clutch bell used regular bearings and not those needle bearings like the single speed clutch bells.
Extended drive cups in the front and rear diffs, they help keep the CVD's in under suspension droop.
Tsais nitro devil rear pipe
Larger fuel tank from the Hpi MT2
Aluminum shocks from the Hpi Brama 10B (pretty sure that buggy got discontinued quick)
and I'm running Hpi Blitz front springs all around
Golden Horizons chassis and motor mounts

[struhall]

You have a link to the build on the nitro car? I am about to start the same thing with mine.

[JpSonoma]

No, sorry. I use to have one on RC Universe way back in the day, but I'm sure all the pictures are probably long gone from that thread.

Is there anything in particular you're looking for? I probably have most of the pictures throughout its life at different stages, as well as what parts I've used before.

[MikeGozz]

Great looking Rally cars you got there!!

I like the RS4 3 idea. You should post some more pictures of the modification you did to it. I'd like to see them.

[JpSonoma]

Thanks, Unfortunately I don't have pictures of all the mods I've done to it to get me where it is today.
The only real important ones are grinding down your C-hubs to get more down travel out of the front suspension.



I would also recomend running different shocks, I use to run these HPi MT front shocks at all 4 corners of my rally for the majority of its life. Depending on what body you want to run you may have issues with getting the body low enough in the front if you use those shocks and stock Super nitro rally front shock tower.



I ran one of the Hpi subaru's for the longest time and luckily the hood scoop was in the perfect location for the shock tower to fit up into it. This is an old picture but you can see the top of the shocks through the hood scoop.





I can tell you that the focus body would not work without triming the front shock tower down, which is why I looked for alternative shocks and ended up with the barama 10b shocks which were shorter then the MT's allowing me to run them in the lower shock tower hole and cut the top of the shock tower off.

My slipper / clutch bell combo.


And a few with the latest shocks and mounting locations.

[JpSonoma]

It's definitley seen it's fair share of mileage and abuse over the years, and I can say for certain it's actually a really capable car for rally use.

Took these pics one winter before I moved down here to the south.

[JpSonoma]

Detailed up the focus RS body finally, also glued the tires up and took it for a quick spin.
Seems to run good, I think the 21.5 is good enough for scale speed.

My only complaint, and maybe its just this particular focus body, but the inner body set sits really low. So low that you can barely see the drivers heads when looking directly from the side.



Aside from that I think it turned out good.

[MikeGozz]

Awesome man! They both look great all around.

I like that you got the HD diff cups going on too, pretty sweet! I've found they hold up really well... the stock parts always seem to get notched up every season. Spending the extra money on the HD cups let you go much longer before needing to rebuild them.

I always like the RS4 electric chassis and I've been running them for years. I took a little different route trying to make room for the battery. I used HPI A960, bent the bracket a bit and mounted it to the upper deck forward of the battery. It worked out pretty good.

I'm actually working on restoring a HPI Super RS4 Electric now. I'm going to post a thread at some point but most of the rebuild pictures are here: Super RS4 EP - Imgur At the moment i'm working through getting all the hardware consistent on it and upgrading everything to the Carbon Graphite reinforced plastic parts.

Anyway if you like the 1:10 stuff you should really check out the 1:8(ish) WR8. It is such a sweet rally beast to drive. I used to own a Super Nitro Rally up until last year and when the WR8 came out I had to get one. All the 300mm wheelbase bodies fit on it just great and it is such a blast to drive!

It's nice to see another HPI fan here... we are few and far between

[MikeGozz]

BTW how is the tension on the front belt on the Rally with it setup like that? I might try that with mine at some point.

[JpSonoma]

Thanks, yeah I'm definitely a diehard Hpi fan, I lost track of how many of their vehicles I own, lol. Probably close to 20 by now. I just can't believe it's taken me this long to build an electric rally.

I always wanted one of those super nitros, but they got discontinued and I was worried I'd never find wheels and tires for it. Then they came out with the electric super and I feel like it got discontinued fairly quick as well.
I have always liked the WR8, and I didn't realize the super nitro rally bodies fit it, that's good to know. I'm secretly hopeing hpi does a gasoline engine version of the WR8 with that new gas engine that's in the savage octane. That might make me hit the buy button.

The tension on the belt feels good, not too tight. Although if you go with how I mounted the bearings you won't have any adjustability, but I didn't really see it being a problem. I did it more for battery clearance then for proper belt tension.

[JpSonoma]

I've been doing a little ebay collecting of some rs4 rallys over the past couple months. Scored quite a few good parts from one car but another car was a complete disaster. I should have plenty of parts to keep them running for years now.





Heatsink motor plate, 2 ball diffs, front and rear graphite shock towers.


I also scored a set of the hard to find aluminum rally shocks.

[MikeGozz]

Nice score on the parts! I just saw a nip alloy motor plate yesterday. Was going to pick it up but someone snagged it.

I don't think I've ever seen a set of the "pro" RS4 Rally shocks in the flesh myself. lol Also a nice pickup.

I have gallon ziplock bags filled with RS4 roller parts from picking up random cheap ebay rollers over the years. At some point I finally stopped... I figured I have enough control arms, bulkheads, etc to keep my cars going for a few generations! Every now and then I still catch myself itching to pick up another though... It's a sickness man!

[JpSonoma]

Ha, yeah speaking of NIP motor mount, although I promise it wasn't me who bought whatever one you saw, I found this one a few years ago at a local hobby store.
I did however snag up this slipper clutch a month or so ago for pretty cheap, debating whether or not to install it.



I'm with ya when it comes to finding parts, it's like a "thrill of the hunt" effect on me, lol. When I see something rare I get excited and usually end up buying it.

[JpSonoma]

Spent a little time digging through all my parts bins and realized I had a slipper clutch for the rally already, just need to dig deeper for the bushings and I'll have myself a complete slipper.



Got around to trimming and fitting the new inner body set.





Nice tight fit around the front steering and rear links.






Also scored some really rare Super nitro rally graphite shock towers for the RS4-3 nitro rally, took me forever to find these. Hopefully I'll be installing them soon.

[MikeGozz]

Looking good! You are making me want to set out to get my rally running

[JpSonoma]

Originally Posted by MikeGozz

Looking good! You are making me want to set out to get my rally running

For sure dust it off, I'm tired of mine being a shelf queen.

Interesting problem I ran across, I installed some brand new hpi UNIVERSALS (not MIP CVD's) in my rally way back when I got it, I was positive they were the correct ones for the rally and even crossed checked the numbers with the option parts listed in the instruction manual.
Anyways, long story short they are too long and bottom out in the diff drive cups and don't allow the suspension to fully compress, kind of annoying actually. They are pretty much un-usable now.

Luckily, I had a set of CVD's collecting dust.




Found all the parts to complete the slipper install.



Finally took it out for her maiden voyage, hard to believe I've had this thing for years and this is first time its seen dirt, lol



Action shot


Not too dirty, and everything held up good. Motor was a little bit warm, probably more from being enclosed in the inner tray with no air flow, I might try to fit a fan or heatsink in if it becomes a problem.

[MikeGozz]

Nice man that car is looking great.

About the CVDs is looks like then ones you have are indeed for the 200mm wide RS4 Rally (it's stock width). You must be running it 190mm wide if they don't fit which is the width of RS4 Pro and a lot of other 1:10 scale touring cars (Tamiya etc). Are your front and rear hubs riding on the inner hinge pin holes on the control arms? If so you have it set up for 190mm width.

It's not a big deal obviously as long as you have the correct dogbones/CVDs and body.

[JpSonoma]

Thanks, it's a fun car. I think I need to add some weight to it though, the car was designed for Ni-cad/Ni-mh battery's from back in the day and I'm running a shorty lipo pack, so even with the hpi soft springs it's still stiffer than I'd like. I'd like to see it soak up more of the bumps and not just bounce everywhere.

Yeah, the universals have me stumped. All my suspension is to the outside holes and the Focus body is a 200mm body as well. The fronts were close, but if I added anymore camber they would bottom out. The rears would bottom out no matter what camber I gave it. CVD's to save the day I guess.

[MikeGozz]

Yeah softer springs will probably help that! I remember ae springs worked well in the car too. I forget the part numbers though lol.

Do you have a way of measuring the universals from pin to pin? They may be the Super Nitro universals. I can measure mine and see if they match.

[JpSonoma]

I have some calipers, so I'll get some measurements when I get a chance. I thought maybe it was the aftermarket rear tower I have, like maybe the shocks were bottoming out first, but even with the shocks off, the chassis would not drop all the way to the ground unless I had positive camber.

I'm still thinking the parts are correct and that maybe some other parts on my car aren't correct. Maybe I can try a ball diff in the rear, perhaps the drive cups are deeper on those? Or I can just get over it and enjoy the car with CVD's lol. I'm pretty sure CVD's are a better choice anyways, I was just thinking universals would handle dirt and sand better and not wear much.