the problem with the exergen on the grp is that it dosent get down the hole at all, the exergen is the best gun you can buy, but the grp hole is small, when i use any other style of temp gun on my engine it comes up with 240, if i use the exergen on the block right under the head its 240 also, its just the design of the head that dosent allow it to get accurate reading

funny how my $20 duratrax or what ever brand it is consistently temps mine at 185 to 190 when I'm on a good tune...

i agree. All guns are not created equal, but that is another thread.

I guess the bottom line is, the GRP is an awsome running engine (IMHO), no matter what gauge your using as a reference. I think we all agree that the GRP6 plug is too cold (in most cases), and that the GR4 (or some other hotter type plug) works better, and that everyone has thier own idea, as to what works best for them.:nod:

Well, I wasnt even trying to be rude and say wrong like it was personal. Just that I was trying almost every ways that everybody else recommened in here until after Adam finally said something to my pit guy about the mill tuning. My pit guy just had it setup wrong, did what other guy told me in the PM.. and it didnt work, was way way too fat, ran at 170.. the odd thing is when after i broke it in and had it run on ground after 4 tanks idle breakin.. it ran at 210 about.. then on the track next day it shows it runs at 160-170.. and was really fat. went lean, at 210 it still runs like its fat.. and it did sounded fat.. so adam said to go for 250-260.. then it ran really good, we didnt change the tuning until my B main, it ran at 210.

Yep i think my binding prob could have been the fuel, but it could have been an adjustment i made also.

I put a little larger ball cup on the ball link witch allowed it to move a little freer than the losi one and also got the engine up to temp where it would bind then adjusted the linkage while it was hot and now its bind free, still binds a little at wide open, but allot better. But also changed fuel at the same time so that could be it also.

In terms of plugs, my C4 that i used for for break in has died at the 4ltr mark, is that good or bad?

Dont have any more GRP plugs atm so im having to use OS's. Put a P3 in it witch lasted 2 tanks then a OS hot plug witch is on its way out, they seem to be dieing under rich conditions with this engine, they seem to be alright if the engine is running under high performance lean conditions.

Also stuck a Jp-3 pipe on the engine and wow was the stock 2053 suffocating this engine, it breaths allot better now.

Well I'm using 30% Nitrotane and my carb was sticking on the first gallon and it is still sticking on the second gallon. My son's Vspec has been fine since I switched him over to Nitrotane. Do I have two bad gallons of Nitrotane?

It was real bad last weekend so lastnight I took the carb apart and polished the slide tube in the carb. It's really free when it cold so I'll have to see when I hit the track again. I hope I can get this resolved because when the carb is not sticking the motor is great.

I am sure Adam wouldn't like seeing a GRP engine run at 250*. On a 110* day, a GRP runs around 210 max. I don't recommend running these engines over 210*.

Hey it was not me who was told by adam.. it was my pit man who went up to adam and asked him. I am deaf so I cant hear a CRAP! All I was told that he said to tune it up 250-260.. and when he did that, i went in for MAIN race.. it went down to 210..

Back to what everyone said about temp guns.. I used my LOSI tune screwdriver that has temp gun too.. it only showed 2 degrees colder than my team buddys big new techolongly temp gun that he spent alot on. And ONFA temp gun showed 10 degrees hotter..

So I want to find the right temp gun for this mill.. any suggestion??

whats wrong with the screw driver...?

Nothing is wrong with it.. even though some guys on my team complains about it.. i guess they think that its not accured.

how many head shims is everyone using on 30% nitro?1stock or are you adding the 2 xtra shims?
thanks

I dont use any shims.. I was wondering the same, but then again adam says that the mill was made for 30 percent and doesnt need shims..

I have question about the grp plugs.. Has anyone tried the PLUS or even know what thats supposed to do?? It seems like theyre making it like splitfire plugs compared to NGK racing plugs.. lol..

To be more specific, on NeoBuggy Adam states that he runs his engines box stock and does not add any shims for 30%. GRP's come shimmed from the factory with (1) .3mm aluminum and (1) .1mm copper for a total of .4mm already installed. So Adam certainly has shims installed in his engines, he just doesn't add any additional shims for 30%.

Good Luck.

yeah
 

yeah thats why i said adam said he doesnt add shims.

Anyhow.. any knowledge on the GRP glow plugs?

Hey Guys

What would be better a GRP 21 or 28 in my RC8T truggy. I know everyone will say 28 as its a truggy engine but to me their just not as good as a 21.

Will i still have plenty of power with a GRP 21, would also get the combo with pipe etc etc.

in the truggy i run my grp with the associated 2035 pipe, 7mm carb restrictor, and os p3 plug, it has plenty of useable power, i would imagine the .28 would just be overkill and get less fuel economy

what kind of runtimes is everyone getting in there buggy and truggy with .21 promokit im struggling to get 8 minutes.i have no problem getting past this with my 2 v-specs.plus my one grp engine lost rear bearing after one gallon.any info would be great.temps are around 210.as of now i have 3 grps running two of them now and one in the box.if it doesnt get any better im going back to os.

i get around 11 in the buggy or truggy, the truggy has a bigger tank but i am on the throttle more so that kind of makes up the difference, i am not using the promo kit pipe it really seemed to hold the engine back

Ok, Would i be better off going with a JX21 over the GRP 21 promo kit for my truggy.

I want to use it in my buggy as well as my truggy??

Im on an open loose/traction track

What carb restrictor are you running? I have been running the 7mm restrictor and a jp-4 pipe and been getting around 11 min on a tank weekly.

ive been using the 6mm restrictor and stock pipe.i love the smooth power delivery but fuel milage is poor.my lowend needle is 3.5 turns out and my highend is 2.5 out.i have my carb idlle gap set at .022.im no newb to racing just this engine has me stumped.:confused:

that seems a little lean on the top and fat on the bottom, mine is around 3.5 turns on the top and 2.5 on the bottom, this motor likes to have a leaner low end to make the power, and get good fuel economy

as far as the jx over the grp i dont know, im not the biggest fan of the jx, its kind of a mix match of motors, has the crank from the .28 zx and the engine case, but a piston sleeve and rod that is similar to the vspec but with 5 ports, i run the speed's and the grp, they both work good for me

thanks for the info cjm1126 .ill try your settings and see how it goes.i have a big race this weekend and i want to do a two stop 30 min main.

one more question does anyone make a ceramic rear bearing for the grp

the tuning of this engine is alot diferent than my v-specs.they seem to like more fuel on bottom and leaner on top.

actually, mine were the opposite..you have to tune the lsn first, then the hsn on the GRP's...get the LSN to where the idle is steady (not dropping after a high speed run), and then adjust the idle screw for desired idle speed, then turn on the hsn...if you have the lsn too rich, you will get a lot of flameouts and fouled plugs - also, this engine runs much cooler then others...mine always came off the track around 190-205 or so

i worded it poorly i meant it to be my v-spec likes a richer low end and leaner upper.

You might also try going to a 7mm restrictor. You would think that the bigger restrictor would cost fuel mileage but I actually picked up some mileage going to a 7mm over the 6mm. 6mm seams to choke the engine alot so your in the throttle more. I also know that the jp4 over the pipe in the promo kit seams to help bottom end and also improve run time alittle.

i havent tried the jp4, but i know that the 9853 novarossi, and 2035 associated pipes made a big difference in performance for mine as well, over the grp pipe, and the economy got better, i also found the os p3 plug to work better with the engine

Yea I heard the same thing bout those pipes but I already had a jp4 on my v-spec so thats what i use.:lol: I also switched to os plugs ran a p3 for awhile but had some issues with them not lasting long so i went to a p4 and have had the same plug in the motor for 3/4 a gallon or so w/ no problems so far:nod:

i looked at the taper angle on p3 compared to grp plug and thought they were different.

now im curious im taking both to work tomorrow and putting them on optical comparator and put my curiosity to rest.ill let all know if taperangle is the same.

someone did a compare of the two with tool and die measuring equipment and found no difference in angle of the two plugs. the P3 was a tad (like thousandths) longer I think. I have been running a P3 since breakin without any problems.

i have been getting around a gallon of fuel out of either of them, the issue's i had with the grp plugs was 3 out of 5 actually worked, 2 of them were bad for the price i was pretty disapointed, i have been using the os p3 in just about everything and they work good

Heres the link to measurements of OS vs. GRP.

http://www.rctech.net/forum/nitro-of...ml#post4398529

Is the associated pipe the same as the Dynamite 053 pipe or the Thunder Tiger 2035 Tuned Pipe?

associated is the same as 2035 thunder tiger, 053 is a copy of 9853,they both work well, i prefer the 2035

Why do you prefer the 2035?

just seemed to have more bottom end power with the pipe, wasnt a huge difference they both work better then the 2053 that comes with the promo kit, if you have a 053 or 9853 allready, go ahead and use it, you will be happy with it, if you are gonna be buying a new pipe you can get the thunder tiger with manifold from amain for 46.99

I heard that a Hong Nor 2062 go mean on a GRP 21 tuned

Anynews guys?

Are people still running os P3 plugs?

Got it.

Does anyone know the stock needle settings for a GRP 21 tuned?