R/C Tech Forums - GRP... Engine... Thread...

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Quote:

Originally Posted by rcracenut (Post 5704945)

Where do you get those? I checked Stormer but they didnt list it.

http://carolinasrc.com/Webstore/Scri...idproduct=8868

http://carolinasrc.com/Webstore/Scri...idproduct=8970

geeze. $11 for 5 tiny o rings. :rolleyes:

Broke in my new .21 Tuned, did the heat cycle, now here comes the fun part, was trying to get it tuned, and ran into my first problem, when going to full throttle I get this bog (for lack of another name) the engines sounds like a deep "BOAAAAAAAAAAAAAA" then a couple of seconds later clears out, tried leaning the bottom, richening the bottom, leaning the top, richening the top and nothing....any ideas, I'm going back to stock settings, but I'm kind of lost on how to tune, I've read that you first set the LSN then the HSN so it just clears out, spoke with some other guys that run same engine and told me to tune like any other, first HSN then LSN.....any help much appreciated!!!!

Quote:

Originally Posted by Toiffel (Post 5712206)

With this engine when in doubt lean it out. I had one GRP that sounded lean at idle and sounded like a lean bog at full throttle like you are describing and I leaned it out a lot like 1/2 turn on top and bottom and then all of a sudden it came alive. Tunning on this engine is different from most. So I lean it out till I know its lean and then richen it back up. The last GRP I ordered from powerhouseperformance and I had powerhouse do the heat cycle. This was done in NY at 20 degree ambient temps. When I got the engine I tuned it in 60 degree ambient temp and I had to lean it out a good 1/2 to 3/4 turn on the bottom and 1/4 on the top. Ran like a champ then. Try leaning it till you know its lean and then richen it back up. If you get lost you can always start over at factory settings. Dont give up you will get it and when you do you will be very happy.

to lean on top to rich on bottom:nod:gets my vote every time because youve tuned it like other motors ...like the guys at the track said ...only problem is they dont tune like other motors:lol:you will get it and like frank said when you do ...its golden

Thanks guys for the help!! Actually it was to lean on the bottom and too rich on top, I'm loving it!!! Can't wait to get it to the track!!

Thanks Alan B., this guy rocks!!! Helped me over the phone!!!!

Alan, have u tried the Losi R10 pipe with a GRP Tuned 21?? What restrictor would you recomend for 8T 2.0 ??

Quote:

Originally Posted by Toiffel (Post 5714838)

Alan, have u tried the Losi R10 pipe with a GRP Tuned 21?? What restrictor would you recomend for 8T 2.0 ??

The 7 is perfect I put the 8 in looking for a little bit more torque and my runtime dropped significantly to out of gas at 8:30. I usually get around 10 min or so. I am running a dyn 053 pipe with a RB long header. The long header really helps out the torque in the truggy.

Great thanks Frank, how does the 053 compare to the JP3? Or the R10?

Quote:

Originally Posted by Frank L (Post 5705470)

My new GRP is doing that too. Check the clutch I had a heat prob a few weeks ago and changes the clutches and then temps that were at 230's down to 175 but then this weekend temps in the 220's and then in the main it came in at 205 after 20 mins of hard running. As long as there is good smoke throughout all ranges I dont worry about it. The front bearing is defiantly a weak spot. I had one go bad under a gal and the other GRP I run has over a gal on it but I know soon it will go bad. Install TKO's and forget about the front bearing. Did you seal the carb and back plate? and how easy do the low, high and idle screws turn. If they turn easy then the carb needs an o-ring kit. The o-rings in this engine dont last too long, I have seen fuel come out of the HSN because the o-rings were bad. I always carry spare o-rings.

its not the clutch. ive replaced the clutch twice since having it.....

i checked for air leaks and found nothing, there isnt fuel on the bottom of the block after runnin so i dont think the bearing bad. and the needles are tight. im just going to lean it out and have it run around 240(guessin this will be where it at) there was tons of smoke at 268 last saturday but thats to hot..... if it blows it blows. im tired of dealin with this engine. my pinch is prob close to being gone soon(maybe 2 more gallons) and it has like 3 on it so o well no more grp for me

Funny question losi_racer....have you ever cleaned the tip of your temp gun ? ive found a little layer of grunge on the "eye" every once in a while and can cause Extreme differences in temp...like a normal running motor temps at 275+ when the motor IS NOT 275...and once you clean it whamo 210-220 like its supposed to be...i have a specific paint brush i use for cleaning the Tip's of my guns that i keep in a Zip loc in the pit box. :nod:

LOL. I've had that happen before. Luckily I caught it before I started twisting needles. Mine was reading below 100deg F everytime I checked the temp.

Quote:

Originally Posted by air8 (Post 5718368)

LOL. I've had that happen before. Luckily I caught it before I started twisting needles. Mine was reading below 100deg F everytime I checked the temp.

Some brand's will go Up...some will go down......my Duratrash back in the day went down like your's.....my OD and HPI went up....crazyness i tells ya. :lol:

Will a mccoy #8 work in a non tuned GRP .21 motor? Also, i made the mistake of pulling out the lsn tonight and didn't get the amount of turns out from bottom before doing so. I have search and found different suggestions on where the factory setting is, but cant figure out what it is suppose to be. Is it 5.5 or 6.5 turns out?

Thanks in advance
Bryon

I'm not sure of how many turns out but the manual says .045" in from flush.