Nitro RS4 3 3.4 build

[TenTlover12]

Well if anyone saw my post “make it good or get a different one” they’ll know that although I did in fact decide to rebuild the rs4 2(go check out that thread) I also ended up buying an rs4 3, which I dropped a t3.0 I had into it, and that was fine, but of course I had to make it more stupid, so…


I decided to put a 3.4 in it! Probably my dumbest thing I’ve ever done with an rc car(actually now that I think about it it’s definitely not, but it’s still ridiculous) a .20 inside or a car meant for a .15, that makes perfect sense, to me at least.

The initial problem was, this was a big block(well small block formfactor but basically a big block) going into a side exhaust .15 platform. So exhaust was one of the first problems, which I solved by using a os .18tm header and a RB TM523 exhaust pipe(I’ll put a resonator in at some point, but I had this lying around so might as well use it)

That solved the exhaust problem, and as for fitting it, I’m not as proud of that solution… unlike the beautifuly done version by @fyrestormer(I think that’s his name? Look up 3.4 rs4 on google and you’ll find his form, he does great work) I basically took my old chassis and motor mounts, and just kinda.. crammed it forward, cut a unprofessional extra space to slide the engine where it needed to go, and it works!


I can’t say I’m proud. But this build was supposed to be a laugh for me,using stuff I already had so It’s not keeping me up at night. These pictures are the final product, I have some of its “pre development” stage that I’ll probably post, but for now I like it, it’s good enough for me, although I’ll probably throw something else in it, the .20 is definitely too much power, but I’ll just enjoy it for now.

Here was the initial build, with a linkage from a jato! Also where I stole the engine from(yes I had a jato 3.4) which as you can imagine, blew up transmissions way too much, I have a much more elagent throttle linkage setup now, along with better wheels and tires as seen in the main post
Here was the rebuild I did before the pictures at the top of this thread, this was a few days ago, and I cleaned everything up, also note the cheap spare tire I had on it and all of its wear!

 

[tudordewolf]

Nice work, I love all "wildcat" 1/10 onroad builds, they're my favorite to do. I too crammed a rear-exhaust engine into a side-exhaust based car with that OS manifold:

Since it's a Losi 3.4, you could throw an OS 11K on there, not that it needs to be souped up any further...

 

[TenTlover12]

Nice work, I love all "wildcat" 1/10 onroad builds, they're my favorite to do. I too crammed a rear-exhaust engine into a side-exhaust based car with that OS manifold:

View attachment 172282

Since it's a Losi 3.4, you could throw an OS 11K on there, not that it needs to be souped up any further...

i thought about that, and I will probably be getting a 11k for the 3.4 in my ten t, but honeestly i am considering switching to a different motor with a little less power, kinda like what you did, not positive but that looks to be an sh engine? its hard to find rear exhuast engines with the threaded crank instead of the "normal" style, but I've already modded for it so, not sure yet, and sweet build dude!

 

[tudordewolf]

i thought about that, and I will probably be getting a 11k for the 3.4 in my ten t, but honeestly i am considering switching to a different motor with a little less power, kinda like what you did, not positive but that looks to be an sh engine? its hard to find rear exhuast engines with the threaded crank instead of the "normal" style, but I've already modded for it so, not sure yet, and sweet build dude!

Thanks, and good eye, it's an SH-12. The chassis is an HSP Flying Fish, a shameless copy of the RS4.

My "stretch goal" for that build is 60mph. It's done 53 so far and had more to give. That's with an 18/23 clutch bell and 44/39 gears in the transmission. It looks like you've got almost the same in your RS4, that's a chunky clutch bell. I used a very similar solution to yours, drilled and tapped the engine mounts to shift the engine forward ~7mm.

The only threaded-shaft rear-exhaust engine I can think of would be a TRX 2.5 or 3.3 with the multi-shaft crank swapped in - I used that exact solution to build the truck in my profile pic, which also has an 11k carb upgraded in.

 

[TenTlover12]

Thanks, and good eye, it's an SH-12. The chassis is an HSP Flying Fish, a shameless copy of the RS4.

My "stretch goal" for that build is 60mph. It's done 53 so far and had more to give. That's with an 18/23 clutch bell and 44/39 gears in the transmission. It looks like you've got almost the same in your RS4, that's a chunky clutch bell. I used a very similar solution to yours, drilled and tapped the engine mounts to shift the engine forward ~7mm.

The only threaded-shaft rear-exhaust engine I can think of would be a TRX 2.5 or 3.3 with the multi-shaft crank swapped in - I used that exact solution to build the truck in my profile pic, which also has an 11k carb upgraded in.

53 is amazing! And yeah I haven’t even thought about the multi crank on the try engines, not a bad idea, tonight I was screwing with a 3.3 in it and I got half way through before deciding… I didn’t feel like making this work completely differently(shorter crank) so now not sure where I’m taking the rs4, the 3.4 is fun but so so so powerful, I really want a motor like yours but I’d rather not buy another starter box, so not sure what to do yet

 

[tudordewolf]

53 is amazing! And yeah I haven’t even thought about the multi crank on the try engines, not a bad idea, tonight I was screwing with a 3.3 in it and I got half way through before deciding… I didn’t feel like making this work completely differently(shorter crank) so now not sure where I’m taking the rs4, the 3.4 is fun but so so so powerful, I really want a motor like yours but I’d rather not buy another starter box, so not sure what to do yet

Yeah, the modern small-block scene is a bit limiting, I find myself building vehicles around the engines I can find. At the least the SH.12 can be purchased new...

I hear you about the starter box, it's a bit of a hike to an area where I can run my nitros, so that's a heavy piece of kit to lug around that I'll only use for 10 seconds anyway. I'm working on a brushless conversion for mine to cut weight.

I've done 50mph with a .12 side-exhaust engine (out of production Thunder Tiger Evo-12...), so they're not obsolete by any means. A Force .15 engine could work, or even a TRX .15 Pro, would make kind of an oddball car. American muscle!

 

[TenTlover12]

Yeah, the modern small-block scene is a bit limiting, I find myself building vehicles around the engines I can find. At the least the SH.12 can be purchased new...

I hear you about the starter box, it's a bit of a hike to an area where I can run my nitros, so that's a heavy piece of kit to lug around that I'll only use for 10 seconds anyway. I'm working on a brushless conversion for mine to cut weight.

I've done 50mph with a .12 side-exhaust engine (out of production Thunder Tiger Evo-12...), so they're not obsolete by any means. A Force .15 engine could work, or even a TRX .15 Pro, would make kind of an oddball car. American muscle!

My best bet for that speed is probably an hpi g3.0, those are amazing .18 engines, so much power, and side exhaust and multi crank design, and will drop straight in any rs4 2 or 3, and as funny as having a massive engine like the 3.3 or 3.4 is, it’s quite unnecessary, these cars will move with almost any engine in them, makes me just wann put a g3.0 in both my rs4s and call it a day… I’m sick of messing with this os .15cvx

 

[TenTlover12]

Alright everyone, change of plans, last night I was cleaning up my workbench and rc area and found a t3.0 I forgot I had, so I got an idea. By the standard of that car it’s a downgrade, but the rs4 3 is getting the .18 back in it, with a new challenge, get it MOVIN! I’m going for 75, but that’s gonna be alot of work, however this is a base rs4, so I’ve got a lot of stuff I can mod to get that speed(trans gearing, pinion gearing, ring gear gearing, because they made 38 and 36, carbon fiber) so it’ll be an interesting challenge to say the least, but the t3.0 is a great motor, I’ll be able to squeeze some pretty good power out of it. And for those of you saying “why would you remove a faster motor and put a slower one in if your trying to go fast?” Because why not? It’s even funnier, anyone can put a big engine in something for power, plus I want the stock look, so here’s some pictures of it, kinda just looks like a stock rs4, but that’s because it is… also one of the pictures is next to my savage, because why not

 

[TenTlover12]

Finally got around to ordering some parts, no fun stuff yet, just stuff to get it going(and some parts I’m replacing just for fun, mainly everything besides the ps and gaskets

 

[TenTlover12]

Did a little more work specifically on the t3.0, although eventually something else will be going in if this can’t provide the needed speed, I still thought I’d rebuild it, and while doing so I was looking for another head, and figured out that with a little trimming(shown in the pictures)on the top4 corners of the block, the head from an hpi s-25 will dig, and any head with that bolt patern. It’s not a super big head so it doesn’t look super stupid so I thought, why not. Also anyone have an idea for a pressure fitting for this cvec? The one I have leaks, but I really would like to run that pipe