ZR.32 Spec.4 engine in a Hpi savage 21?

Nitroholic

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Hi! New in forum and my first post. I recently purchased a savage 21 in Good working condition and now i wonder if the ZR.32 Spec.4 engine is a direct fit to it? With my other stock parts? I also purchased a New never used 3 shift gearbox assembled. I already have the reverse modul in my existing gearbox but ive been told that i Can just move that over to the New 3 speed gearbox? Thanks for any response. With regards Fredrik
 

Jam Racing 1

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Hi! New in forum and my first post. I recently purchased a savage 21 in Good working condition and now i wonder if the ZR.32 Spec.4 engine is a direct fit to it? With my other stock parts? I also purchased a New never used 3 shift gearbox assembled. I already have the reverse modul in my existing gearbox but ive been told that i Can just move that over to the New 3 speed gearbox? Thanks for any response. With regards Fredrik
Yes the LRP will direct bolt to your truck, you will be using the flywheel and clutch but you may think about going to alloy shoes and a bit heavier springs like a 1.1 set

If you gonna upgrade the :ercm: to that LRP then you will want to also upgrade the differentials to the 29/9 machined gearsets and also upgrade the spider gears to the 4 spyder and also upgrade the differential cups to stronger alloy parts...

Putting more power in is going to reveal the weaker parts really quickly for sure.....
 

Nitroholic

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Yes the LRP will direct bolt to your truck, you will be using the flywheel and clutch but you may think about going to alloy shoes and a bit heavier springs like a 1.1 set

If you gonna upgrade the :ercm: to that LRP then you will want to also upgrade the differentials to the 29/9 machined gearsets and also upgrade the spider gears to the 4 spyder and also upgrade the differential cups to stronger alloy parts...

Putting more power in is going to reveal the weaker parts really quickly for sure.....
Thanks for that info. Yes, i understand that this rc not was intended for the amount of punsch the LRP can provide. I'm going to upgrade everything as the Times goes. Do you know if i was correct informed about my gearbox?
 

Nitroholic

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Thanks for that info. Yes, i understand that this rc not was intended for the amount of punsch the LRP can provide. I'm going to upgrade everything as the Times goes. Do you know if i was correct informed about my gearbox?
Thanks for that info. Yes, i understand that this rc not was intended for the amount of punsch the LRP can provide. I'm going to upgrade everything as the Times goes. Do you know if i was correct informed about my gearbox?
Jam
Yes the LRP will direct bolt to your truck, you will be using the flywheel and clutch but you may think about going to alloy shoes and a bit heavier springs like a 1.1 set

If you gonna upgrade the :ercm: to that LRP then you will want to also upgrade the differentials to the 29/9 machined gearsets and also upgrade the spider gears to the 4 spyder and also upgrade the differential cups to stronger alloy parts...

Putting more power in is going to reveal the weaker parts really quickly for sure.....
Is there any way you can see, if the parts you describe already has been upgraded? I don't know what is stock and whats upgraded in mine but both differentials are in metal. All of the driveshafts are in metal and also the hubs for it. Does somebody know if this is stock or not?
 

Jam Racing 1

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Only way one of us can tell is if you post clear close up pics, as for the differentials you need to remove them from the truck to see what has been done and if they are ready for much more power........
 

Nitroholic

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Only way one of us can tell is if you post clear close up pics, as for the differentials you need to remove them from the truck to see what has been done and if they are ready for much more power........
Ok, i understand what u mean. I just meant that the parts i tested are in metal. Thought that maybe some parts were made in plastic from stock.
 

Jam Racing 1

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Ok, i understand what u mean. I just meant that the parts i tested are in metal. Thought that maybe some parts were made in plastic from stock.

Most of the suspension arms and related parts are plastic, the differential gears are metal but the 29/9 machined gears are usually only put into high power rigs such as the XL and Flux models also the differential carrier on the earlier models were plastic and not alloy which holds gear mesh tighter as things heat up from using them, so as I stated clean up close pics will help determine what you currently have on your particular rig
 

Nitroholic

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Sweden
Ok
Most of the suspension arms and related parts are plastic, the differential gears are metal but the 29/9 machined gears are usually only put into high power rigs such as the XL and Flux models also the differential carrier on the earlier models were plastic and not alloy which holds gear mesh tighter as things heat up from using them, so as I stated clean up close pics will help determine what you currently have on your particular rig
Ok, thanks for that usfull info. As i have the plastic differential carriers its probably stock then.
 

js1badsti

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37
you must be in a lucky situation to get an lrp motor --I have a zr30 and can not find anyone who still supplies the LRP motors in the US. in case I might need a new one down the road.
 

js1badsti

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I was afraid of that --a while back I heard from my LHS that LRP closed down there motor division and the LRP nitro motors were no longer being made. sorry for the bad news but hopefully you will get it --they are real powerhouse motors.
 

Nitroholic

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Location
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i scanned the Web for the ZR.32 Spec.4, and it seems like there are more than a few availble in rc-shops in italy and germany. If you are in need of that particalar engine i mean.
 

Nitroholic

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I Will post info about my model, the savage 21. If i read this right and if the info is accurate, it seems like the truck is pretty solid and well build from stock, right?
 

js1badsti

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37
yes it is well built and will take a beating.I would suggest puting a wheelie bar on it if you get the lrp motor--it will rip the front end up in the air with authority. lol
 

OnThatPipe

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I don't think you need to change your diffs just because you are putting on a new engine. I've run that Spec 4 and it is close to that F4.6 vs other engines I've run, including a Roma, 28-7, Bonito, Speed Spec II, etc. (some of them I even modded).

Never had a single issue with ,my Savage diffs...on any engine.

The only issues I had were with the 28-7 and the Roma, specifically keeping the front end down. I couldn't go 1/24 throttle before the front would lift. I softened everything up in the back, I put limiters in the rear shocks, reduced the damping, lowered my clutch engagement (was using mainly Buku and M2C so could tailor all that). Changing the setup helped some...but it got to the point it was simply no fun because I could not keep the truck from doing wheelies (even at 3/4 WOT). I could get very close to a standing back-flip...but then put the stronger engines back in truggies where they belonged. lol

I only put a few gallons each on those engines due to the power, but again I can tell you the gearing held up just fine, so you will have no problems running that Spec 4 (or if you do, it's not the engine). Good luck
 

Nitroholic

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Thanks for that input! Can anyone tell me about with gear ratio could work? I have the stock 52 teeth in spurge gear and 14 teeth in clutch bell. Changed the spurge to all metal gear. Will be using the 3 speed transmission too so you now, if thats relevant in the matter.
 

Sparky

Active Member
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16/52 would be a better gearing combo,
Unless of course your running very overweight wheels,

The lrp32 is a huge difference in power than a f4.6,
I've ran a lrp30 when they were first released a few years back in a savage xss and it was a massive change in power over the f4.6 engines I run,

I've a modded lrp30 from Neal smith at TNS and couldn't keep my 3 speed gearbox in my savage XL
in one piece for more than a couple of outings,

So now run a force 36 in my xl and have the modded Lrp in my Lst2.
 

OnThatPipe

On a vacation
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I've a modded lrp30 from Neal smith at TNS and couldn't keep my 3 speed gearbox in my savage XL
in one piece for more than a couple of outings,
Assume this is Neal Smith from CRE? When he and John had their shop they modded some engines for me waaaay back.
Surprised he even started modding LRP's. lol
I still have a Nova 28-7 he modded for me (if you have driven a stock 28-7 you can imagine what a modded one is like).
Ran the crap out of it and it never hurt my gearing, but again just with some other wicked strong engines I've run on it (Bonito, 28 XZ-B, R1, Roma, WR5,) it was simply too much from a handling performance. Still I wanted to find out "what if" and I did. Right now I mainly just switch out between my 7-port Vir-Tus and B5 on the Savage as they give all the power that is needed and nothing more.
 

Sparky

Active Member
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neal always had a gripe with the lrp engines and refused to take these engines seriously,
Turns out that when he started modding them they became the most powerful engines he's every worked with,

Pulling higher rpms and Hp figures on the dyno than any engine he has ever modded,
He had an lrp30 in a stock length savage That could do standing backflips
Neal now has a lot of respect for these mills,

I've a couple lrp30s from him and they are absolutely insane,
They are turning such high rpms in neals testing on the track and dyno that he's advised that
if running in a truggy/buggy I've to remove the pullstart and put on a bump start backplate as no oneway bearing can stick the rpms as he's had bearings go to pieces during testing.
 

Nitroholic

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Location
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Will gearing 16/52 still make powerwheelies? I am not interested in exessive top speed. I rather want thourge. Another question... my steering servo broke down. I have changed the servo but when i steer you can really see that everything wiggles. The steering post and the things who are included in steering parts are stock. There are a ton of so called steering servo savers out there but Is there someone u can recomend and someone you shoùld watch out for?
 

Sparky

Active Member
Messages
100
To be honest you'd be better with 17/47 if your going to be running an lrp32,
It will wheelie easily an go on wheeling for as long as you can hold onto the gas,
Or as mine does wheelies until it gets into a speed wobble,

The 16/52 is suited to the larger diameter tyres such as the savage XL Terrapins.

As for the steering servo saver on the savage 21, the stock unit are too weak and cause way too much steering slop,
You should upgrade your steering setup to the savage X setup,
It has a heavy Spring servo saver built into one of the steering posts and can be adjusted how you like to have it,
With a solid servo horn attached to the servo,
This will eliminate a lot of the slop in your steering.
 

Nitroholic

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Location
Sweden
To be honest you'd be better with 17/47 if your going to be running an lrp32,
It will wheelie easily an go on wheeling for as long as you can hold onto the gas,
Or as mine does wheelies until it gets into a speed wobble,

The 16/52 is suited to the larger diameter tyres such as the savage XL Terrapins.

As for the steering servo saver on the savage 21, the stock unit are too weak and cause way too much steering slop,
You should upgrade your steering setup to the savage X setup,
It has a heavy Spring servo saver built into one of the steering posts and can be adjusted how you like to have it,
With a solid servo horn attached to the servo,
This will eliminate a lot of the slop in your steering.
Thanks for the tip, I'm gonna look into that emmediatly.
 

olds97_lss

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Dekalb, IL 60115
From what I saw, LRP is coming back. If I find the link again, I'll post it.

I run the LRP30S2 in my savage X with 17/47 gearing and alloy shoes. It has no problem running wheelies all day long with traxxas 3.8" 3.3 max wheels/tires. I have the T-Bone rear skid/wheelie bar on both my flux hp and X as it really helps the body last a lot longer since it sticks out a bit further. It works far better than the HPI wheelie bar.



Guess I don't have any photo's with the current t-maxx 3.3 tires I'm running, just the 3.8" traxxas chevrons. They are a bit smaller OD than the 3.3 tires.


The ones on the right are in the photo above. The ones in the middle are what I run now.
 

OnThatPipe

On a vacation
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neal always had a gripe with the lrp engines and refused to take these engines seriously,
Turns out that when he started modding them they became the most powerful engines he's every worked with,.
Ha ha. That's cool and all, and I'm sure it's a screaming engine no doubt. But Neal is always woofin that about the most powerful he has (especially one for a new market like this). He knows damn well his modded 25-XZ-B is the nastiest engine he's ever run. In his life. Two words for him: Truggy/086. He also knows I have a stock one that will match anything he's modded. His sh*t is bad. No doubt about it. He can tune, and so can I, whereas I know about the Savage.

He knows how to get the most out of these engines, for sure. Not many can, in my humble opinion. I like Neal though, but he's a salesman (and a damn good one too, ha ha).

Trust me, brother. The O.S. 25-XZ-B is the nastiest engine that has ever been ported/modded, until I see differently. That's just how it is. lol
 
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Nitroholic

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Got the LRP 32 today! 😃👌🤘 here is some pics of the engine and accesories. I went with the backplate and rotostart too. Hope i Will get satisfied. 😁 does anyone know if the rotostart fit with savage 21 without any modds? I'm guessing it goes in the rear so i am mainly thinking about if it goes Free for the suspension?
 

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Sparky

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Well at that time,
It's been about 2 years since then,
I've got 3 stock lrp30 engines,
and 2 modded by him,
the rpms are way up along with all over torque on the modded lrp30s
The sleeve ports are enlarged significantly over the stock lrp30,
Along with crank timing enlarged,
I cannot comment about the os25 engine as I don't own one,
But as I've said before I don't comment on things I've not owned.
 

OnThatPipe

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Yeah I get it.

Hey, how are you even able to keep the front down when it's going? When I make some of these engines come correct on this thing, I simply cannot overcome the design. Those modded 28's are meant to do standing back flips. Especially that five port (which peaks sooner but has more grunt) I was very close to them once...but I mean c'mon. It's a party trick to me. lol I need to get paid if I'm going to get it to do a standing backflip as I would lose parts determining how to do it, I'm sure...but I'm extremely confident I can. Especially since I saw it in the Flux. Nitro can do that, no doubt...but damn it gets old fast.

I do a lot of trick wheelies and have learned when I can control the power band I get a better wheelie. But with some of these engines the weight is transferred so quickly the rear can't react (squat) in time so by that point the has won and it's not going back to the front of the truck.

I've worked a lot with weight transfer on this truck, and I've concluded for me to keep the nose down with certain engines it would no longer technically be considered a truck (I have trouble getting 28" truggies with center diffs to squat sometimes anyway).

With this being my only MT I try to keep in the spirit with it as much as it tempts me. lol

On high-bite I like a nice B5/with a 2058/3-shoe M2C (med) with 1.05 springs, on a TRF 13-T bell. M2C flywheel is light (only 19 grams), but you can add up to 5 grams if it gets too snappy. The B5 doesn't vacuum at all on that 2058 and if you give it that 2013 on this Savage there is an initial jolt that is hard to overcome. I initially wondered if it would be able to pressure correctly on the compression stroke but its pairs well. So in my experience the B5, Vir-Tus 7, and that Boost TB seem to be the limit I can go with it. The point of no return when it comes to power would start with maybe the Bonito. It's a .21 engine but shouldn't be. Now that I have myself salivating, I have one of Neal's famous P5's (truggy mod) I'm unsure if I've ever run in the Savage. I need to get on that as it seems like it would be a blast!
 
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Sparky

Active Member
Messages
100
I'm running a modded lrp 30 in a savage Xl,
Using 0.9 clutch springs with HN long life alloy clutch shoes,
This way the clutch engages sooner in the rpm taking a little bit of the snap away,
My savage XL breaks loose on all surfaces on acceleration if I nail the gas,
but if it's rolling and I nail the throttle it's flip clean on its lid,
I like the feel of a truck having a lot of power on tap,
The savage xl is more suited to high power engines than a X length
I had a X length savage a while back with a stock lrp30 and got pissed off driving it as it constantly flipped over,

I've got used to a way of driving with higher power on my savage flux and am used to having a lot of extra power in reserve,
 
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