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-   -   GRP... Engine... Thread... (https://www.rctech.net/forum/offroad-nitro-engine-forum/211114-grp-engine-thread.html)

JBURCH 09-06-2008 08:59 AM


Originally Posted by Geo Y-Rock (Post 4810315)
+1 with the GRP 4 plugs. Better idle reliability. Best engine I've ever run. I'm curious about the .28 for truggy. I'm thinking the .21 is plenty of power and will get better economy. Has anyone run both in their truggy? I've run both the JP 3 and the GRP pipe with my .21. I was lean bogging on top with the JP3. I think the stock pipe is easier to tune.

A buddy of mine runs a .21 in his 8T and believe me he has enough power to stay at the front if his driving would improve LOL. He has even told me that he sees no need in the .28 GRP since his .21 does the job quite well and hes pulling 11+ min run times

rrawrrrrr 09-06-2008 09:09 AM

Hey guys, thinkin of getting one of these for my Kyosho MP777 WC.. anyone have experience with the GRP Promo Kit or just the Tuned .21 version of this engine in a K car? How does the combo perform?

:nod: Thank you :)

El Tigre 09-06-2008 07:36 PM

I just brought a GRP .21 about three weeks ago. I did the break in and I'm having some issues with it bogging out in the middle of the acceleration curve. It's like it's running rich but if completely bogs out when I lean it any further. Once it's warmed up it's a scalded dog but once it cools off it does the same thing bogging out in the middle of the acceleration curve. Oh and how about this, it accelerates fine when the glow plug igniter is attached to the glow plug. I'm running OS p3 Ultra Hot glow plugs which a lot of guys recommend.
I've heard that the GRPs run cool and take about a gallon before it clears the break-in so please let me know if this will improve over time as I run more gas through it.
HALP!!!

jsmax 09-06-2008 08:13 PM

Generally, if it runs better with the ignitor on, but not so well with it off, means the plug is bad. Try a new plug.

gtsum 09-06-2008 08:29 PM

reset your needles back to stock positions and put a new plug in there. Get her to run and warmed up and start tuning on the LSN until you get a steady idle, good take off, no bogging, etc, then tune the HSN. This mill likes a leaner bottom and slightly richer top end...you need to tune it with the LSN to get best results. You will know you are there when it will idle good, take off with a slight puff of smoke and pull through the RPM's with a good smoke trail. It will temp around 180-210. Once you get the LSN set right, it tends to keep a tune very well

DirtyDezPirate 09-07-2008 08:00 PM

Hey, I want to know about GRP glowplugs.. are they fumiliar to OS glow plugs? i mean those number idfenction.. like number 3 to number7 and which one is highly recommened for a .21 grp 01 tuner engine combo that i just bought.. I am switching from OS vspec eb mods to GRP tuner.

cjm1126 09-07-2008 08:13 PM

use the os p3 in the grp, the engine will run much better, the grp plugs make the engine finiky

gtsum 09-07-2008 08:13 PM


Originally Posted by DirtyDezPirate (Post 4815115)
Hey, I want to know about GRP glowplugs.. are they fumiliar to OS glow plugs? i mean those number idfenction.. like number 3 to number7 and which one is highly recommened for a .21 grp 01 tuner engine combo that i just bought.. I am switching from OS vspec eb mods to GRP tuner.

GRP Plugs - lower numbers are hotter...run the GRP 4

Jonro 09-07-2008 09:12 PM

Ive read now, a few times, that GRP plugs are the best for GRP engine because they are specifically made for GRP turbo engines, so they have a perfect fit. I think its just a matter of finding the right heat range(plug) for the fuel and conditions your running in.

Im not %100 sure about this but OS plugs are made for not only their land running engines but also their airplane and boat engines also, so i dont think they would be as a good fit for GRP turbos.

I realize the GRPs are twice as expensive but ive read also a few times now that they last a hella long time, i think OS plugs are fine to use if you are stuck without a GRP plug though.

DirtyDezPirate 09-07-2008 09:53 PM

well if you look up losi and assoicated parts house, theyre much affordable than anywhere else.. i bought my grp .21 tuner 01 promo kit from them for only 440 with shipped and everything covered.. after tax.. it does come with tuner pipe that fits right for these engines.. So, im thinking of getting the GRP plugs maybe they are copied of O.S. plugs cause they both look much alike.

Nitro$junkie 09-07-2008 11:23 PM

I got my promo kit for $309 USD and it was $29USD for delivery from here
http://shopping.rcmodel.hk/product_i...ducts_id=13053

Jonro 09-07-2008 11:28 PM


Originally Posted by Nitro$junkie (Post 4815677)
I got my promo kit for $309 USD and it was $29USD for delivery from here
http://shopping.rcmodel.hk/product_i...ducts_id=13053

Same here, awesome price. Almost seems too good to be true. And only 4 days to my door.

They also have V-specs for $200.

anthony_ling 09-08-2008 04:12 AM

GRP .12 Touring
 
Hey GRP owners..
I purchased the GRP from http://shopping.rcmodel.hk/product_i...ducts_id=13052

Yeah delivery was within 4 days to Australia..

I've just started the run-in process as per the manual, ite been really easy to startup and break-in my only tip would be to lean the HSN about 1/2 turn and LSN 1/4 from factory, you may find the factory settings too rich to start it for the first time... so soon as you have it running... richen the needles back up again..

During the brake-in did you guys run 11 tanks total before tuning or just 6 ? Page 10 of the manual isn't really clear on this... i'll be doing to 11 tanks to be sure...

El Tigre 09-08-2008 10:04 AM


Originally Posted by gtsum (Post 4812383)
reset your needles back to stock positions and put a new plug in there. Get her to run and warmed up and start tuning on the LSN until you get a steady idle, good take off, no bogging, etc, then tune the HSN. This mill likes a leaner bottom and slightly richer top end...you need to tune it with the LSN to get best results. You will know you are there when it will idle good, take off with a slight puff of smoke and pull through the RPM's with a good smoke trail. It will temp around 180-210. Once you get the LSN set right, it tends to keep a tune very well

I'll give that a try. Thanks.

gtsum 09-08-2008 10:10 AM

Sure thing. You will find this mill does NOT tune like an OS engine. It is likely my favorite mill I have run yet - good (not brutal) low end, wicked mid range and a good top end...10 minute runtimes and low temps and keeps a tune...good luck!


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