RE: Official HPI Hellfire Thread
 

The old "my hellfire turns like a bus" comment. Mine turns like a whale not a bus.
The servo horn hitting the servo, one of the many hellfire issues. Most can be fixed tho, with patience.

RE: Official HPI Hellfire Thread
 

that is a very old video !!!! And by no means is that Mach a powerhouse by todays standards LOL !! Yet even still it was wheelying that Hellfire pretty decently...sometimes if an engine has too much power it will not wheely, it will just spin the tires instead..... I actually get more wheelies with a modified .21 then I do with a modified .28, the .21 seems to be able to plant more power to the ground then the .28's.... the .28's just overpower the tires ..... you need traction to wheely......

I would be hard pressed to make a modified Mach 427 even keep up to a stock OS 28... as you say its apples to oranges, a RTR engine vs one of the most powerful .28's ever built........

RE: Official HPI Hellfire Thread
 

Mcrazy glad you are coming home safe. What happened to the videos of that track though?
As far as the wheelies go I think he was referring to wheeling from a stand still. My MT2 with the OS TZ in it will wheelie down the block if it hits the slightest bump but not from a stop.
The weather here has been horrible for too long. I cant wait to get my stuff out and do some driving.

RE: Official HPI Hellfire Thread
 

My Hellfire seemed to turn pretty well when I was trying it..then again it has an upgraded high torque all metal gear steering servo, every HPI I've owned required a new steering servo though, the stock ones are just so weak.

RE: Official HPI Hellfire Thread
 

Thanks for the replies but it will be a while before i can see if this is the problem because where i live there is snow, and i asked you now because I just remembered that I had a problem with it.
I have had to replace the steering servo already and it is a JR650M, so could the servo horn hitting the servo still be the problem?

RE: Official HPI Hellfire Thread
 

Check it out with your peepers. Obviously one side is different than the other. Check for binding or (#1 choice) blockage. I'm sure your powers of observation will notice the difference.

RE: Official HPI Hellfire Thread
 

Noted & thanks.

RE: Official HPI Hellfire Thread
 

I will have check that out then

RE: Official HPI Hellfire Thread
 

Got one of the GST diffs today, holy cow these things are beefy!

However, once again, stopped by a screw. Both the front and back differentials, the the top left screw is stripped. Ican't really take a dremel to this as the screw is recessed in the plastic, I'd have to seriously damage the plastic to extract the screw, any ideas? Surely someone else has encountered this problem?

RE: Official HPI Hellfire Thread
 

Unless you have a good quality set of wrenches the HF screws strip very easy. I always stripped the screws until i got a decent wrench set. I never srtip them now.I think you will have to use a dremel. Those screws do come out easy when you can get a hold of them.
Wait to you put the gst pinion next to the stock pinion. You will really see the poor quality and small size of the HF pinion.

RE: Official HPI Hellfire Thread
 

Ibought some of the "Grabit" screw extractors, size #1 looks like it should extract the diff screws size wise, but for the smaller ones on the Hellfire (if they do strip)I'd need the micro kit. Using a dremel...would be a last resort as I'd have to seriously cut into the plastic to extract it...I'll try the extractors when I get my drill tonight. Also, my understanding by looking at the GST, is that you take apart the GST, and rebuild it on the HPI houseing? Basically take off a part of the HF diff, replace it with the GST part, etc?And I'm guessing to get the screws out Ishould heat in the oven like suggested earlier, @ what temp and how long?Thanks!

RE: Official HPI Hellfire Thread
 

The gst pinion and diff fit inside the HF plastic diff cups. Just some shimming is required. If you want to check/change the oil in the gst diff before putting it all together take the 4 screws out of the crown diff change the oil to the weight you want. I tried this but the screws were so tight they started to strip so i put the diff in the oven at 150 celcius for 5 mins and this loosened the locktite on the screws and they came out fairly easy.
Becarefull of the little screws on the HF plastic diff cups as they strip easy.
Remember to put some grease on the teeth of the pinion/crown before putting all together. Not to much grease.
The picture on page 57 shows exactly what it should look like before closing up the diff cups.
Rember to replace the bearings if they are worn/loose.

RE: Official HPI Hellfire Thread
 

Oh wow, I thought I had to take the GST diff completely apart, didn't know Icould just drop it in the HF Diff houseing, that's nice:D
This thing came perfectly greased, it seemed the guy just buys Genesis's and takes the part off, never been used, and oiled\greased like it just came from the factory. I don't have any shims yet, what size should Iget?You have the same truck as me so whatever you used should work perfectly

RE: Official HPI Hellfire Thread
 

There should be some in your hellfire diff cups but you will need quite alot. I think they are size 13x16x.2mm

RE: Official HPI Hellfire Thread
 

I
EFFIN
LOVE
Grabits!

Ok this thing is amazing, it worked PERFECTLY extracting the screws. One side is a re-taper it drills into the head, then you flip it around and use the extract bit on reverse, it works FLAWLESSLY, I am in love with this!I wish Ihad it whenIwas working on my chassis :(
Ithink EVERY R\C owner should own these bits
http://www.asseenontvguys.com/produc...rabit_demo.gif

RE: Official HPI Hellfire Thread
 

Cool. Where did you get it from? Would cut down on a lot of dremeling.

RE: Official HPI Hellfire Thread
 

Got them from Lowes, already removed 3 messed up screws with them. I did make one big mistake...Idid not heat up the gst diff...now that screw is stripped, even Grabit can't get that one out, it's just too in there, on a good note Idid discover that my Hellfire has "like new"stock diffs, the front and rear Ipopped open, and both are perfect, very little to no wear, the previous owner greased and oiled the crap out of them.

Ineed a bunch of screws now, and after being lucky with finding the Grabit, Ireally still don't want to use these stock screws, I've seen the RCSCrewz Hellfire RTR kit which are full stainless steel, won't corrode, and they claim "Never deal with a stripped head again"but the RTRhellfire screw kit from them for 30$ has 150+ ss screws.

RE: Official HPI Hellfire Thread
 

I'm having real problems with my 4.6HO over heating. It easily goes well over 310f. does any one know the standard needle settings so I can go back to the begining and retune it?

I get plenty of smoke (can't tell if it is white or blue though) when running wot but almost none around mid throttle.

I don't want to knacker my engine, so any help is appreciated.

Cheers

RE: Official HPI Hellfire Thread
 

HPI states factory settings are all needles flush.

http://www.youtube.com/watch?v=ma2_CghxiUk&feature=fvsr

Google is your friend.

RE: Official HPI Hellfire Thread
 

Thanks Nitro, I know I should google everything really but I'm lazy :) I guessed if i posted here I'd get an answer that would save me trawling through google.

As for the flush settings, the HSN on my 4.6HO doesn't have a flush position as the screw is not in a 'surround' if you get my meaning. The whole HSN turns, so I wondered if i twist it one way so it won't turn any more, how many turns back would I need to do until it is at factory setting. My mid and low needles appear flush, so I guess I'll just have to richen them a bit more until I see some smoke around mid and low throttle.

Thanks again though.

RE: Official HPI Hellfire Thread
 

Well if your at 300+ temp, then your clearly wayyyyyyy to lean, so def richen it, you'll kill that engine real quickly if it's more lean than rich.

RE: Official HPI Hellfire Thread
 

You could also have an air leak somewhere. Check the fuel line for cracks and check the carb to make sure its tight

RE: Official HPI Hellfire Thread
 

I checked my old 4.6 ho. The high speed needle sits in a black casing. If your not careful the whole casing turns with the needle. You need to ensure the casing doesnt turn only the needle. The stock settings are flush on all 3 needles. I had to seal the mid range up or it would come loose and fall out.

RE: Official HPI Hellfire Thread
 

Got the stainless steel Hellfire screw kit, the difference is night and day, it's like comparing a old ford to a new Rolls Royce, way more threads, extremely strong threads and heads, and they just look great on the truck. I've started taking off and replacing, a few stock ones on the lower chassis are stripped so I may or not replace those, no need for the hassle if I don't need to access that part, but these new screws I am most defiantly not expecting to strip, A+ quality.

RE: Official HPI Hellfire Thread
 

the low speed, mid range, and idle adjustment should be set flush with the carberator body and the high speed needle should be set flush with the groove that is on the gold stem that the high speed needle is on