HPI K5.9 versus FC R38 for Savage

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Clifffff

Active Member
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112
Hey guys,

Does anyone have experience with both of these two engines in their Savage? If so, could you please post your thoughts on how they fair against one another?
 
A force 28 will blow the k5.9 away,
In low end power and on high rpms,

I've had 3 k5.9 engines,
They struggle to clear out at top end and drink fuel for what power they have,
I'm running a force 36 in my xl now and have nothing but good to say about it,
The k5.9 will load up and stall when let idle for a while as soon as you hit the gas,

The force engines run an idle for as long as I like and instantly Rev out when the gas is hit,
 
I bought the FC R38. I have the K5.9 already and find the consumption insanely high. A huge problem though with the FC, I can't get the damn thing started!!! I have tried everything: heating the engine with a heat gun, loosening the glow plug a little, even sending a few drops of fuel through the glow plug hole but all to no avail. Any advice? (I probably have to start a new thread on this...???)
 
What are you trying to start it with?
Pull start?
Cordless Drill on rotostart?
 
Roto start. I know it has less torque but I can't imagine what my hands would look like if I used a pull starter... The engine is really hard to turn...
 
I had to use a corded drill to get enough speed built up to start my f36,
Even my 20v cordless drill wouldn't start it,
After its broke in it'll start with a rotostart
 
Hi friends. I have experience with each of those and IMO the F4.6 is as good as any of them. I too have three of the 5.9’s, and I have 6-7 of the 4.6 (both versions). I think the 5.9 gets a bad rep but still prefer the 4.6 over it. All in all they are very close to each other. Here in a bit I will write out the engines ive run in the Savage and rank how they fared. The only thing I’ll tell you is the 4.6 is toward the top of that list. I think the challenge is that it’s difficult to tune and engine on the Savage due to its design so I sense that folks are hoping a different engine will suddenly tune itself and that just doesn’t happen. If anyone can show me their aftermarket engine blowing away an F4.6 I am down to see that..:but to date I haven’t. Hey it’s cool having a lot of options (I’ve run ~15 in my Savage) but again don’t overlook that 4.6. It’s a nice starter engine that when tuned can make that Savage come correct.
 
Make sure your engine isn't hydro locked (roto-start engines are real easy to flood). No new engine should require that much torque IMO. Took me forever to realize I was flooding mine when I first started with rotostart. In fact most times I don't even prime with it.

Unflood and try to start without priming it. The plug needs to be on tight.. Assuming your running at least a charged 7.2 in your roto-start it should turn over without an insane amount of torque. However, having .0000% too much fuel spill in to it then it will be incrediblly difficult (and affect the seating of the piston. Triple check it's not flooded.

Also make sure your wand it lined up directly with the bearing. If you have a wheelie bar that can affect it.
. .
 
Have you broken in many engines?
The pinch in a large engine like the force 36/38 lrp30/32 can sometimes be extreme,
To the point where I've had to wind the engine down from Tdc with a screw driver on the flywheel with the glowplug loosened,
I don't give information on hear say and speak from the experience,
I've had with the large amount of nitro engines,
Any of these engines I've listed above will blow away a force 28,
The force 28 is a good wee engine but won't hang with the above mentioned mills.
 
Have you broken in many engines?
The pinch in a large engine like the force 36/38 lrp30/32 can sometimes be extreme,
To the point where I've had to wind the engine down from Tdc with a screw driver on the flywheel with the glowplug loosened,
I don't give information on hear say and speak from the experience,
I've had with the large amount of nitro engines,
Any of these engines I've listed above will blow away a force 28,
The force 28 is a good wee engine but won't hang with the above mentioned mills.

Hi there. Yes, lol I have broken in hundreds of engines (literally). I offered it as a service at our track (along with engine modding).
I currently own 30-40 engines right now, all of which I broke in. I wasn't aware, however the engine size affected the pinch.
Granted I've only broken in maybe 5-10 .32 engines..
If I had to guess, I'd say the Speeds (specifically the Spec II and R2013) have had the tightest pinch out the box...but that is just my experience. 28-XZ B is a PIA as well.
The vast majority of engines I've broken in have been via a bump box, but I do own quite a few pull/roto-start engines. Again, if common methods are not working to turn over and engine, there is something wrong. I'd recommend troubleshooting it before getting out the power tools because if an engine is started with power tools while hydro-locked, the engine won't be much hard to turn over for too long because the pinch will gone fast...so problem solved.
 
Ive had engines still lock at gallon+ of fuel,
its not uncommon to get that,
I've a force 28 in a truggy with 3 gallon run time on it, with still being tight at Tdc,
You will only loose the pinch quickly if you don't heat cycle during the break in,
Cannot be lost turning the engine over with a drill?
 

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