.28 to much ////my extech .24 is just about to much ...go with the .21
on the pipe i have now tried both 2053 grp and dyn 053 ...the 053 gives more power and the 2053 gives better milage ..i got with the smooth gas mileage every time ...the 2053 is better for me

Is it common for these motors to run hotter then 170 to 190 range during the first gallon? i did the heat cycle break in and when i start to tune for race settings it runs great but temps are in the 212 to 220 range i have about 3/4 of a gallon on it with byrons 20% race 12% oil it has good smoke just curious if temps will start to drop after a gallon or so. i reallly dont want to hurt this motor i love it so far

Tune to smoke and performance every time will always yield the best results. I have broke in 2 GRP's recently, both are under a gallon and they both run at 210 - 225 when they come off the track even after a 30 min main. People say it isn't ok for these engines to run above 200, i disagree. My last GRP ran at the same 200 - 220 and was going strong after 7 gal. I tune to temp and performance and it has never failed me yet. 2 of the same engine will tune differently and temp differently, as long as these engines dont get excessively hot, and you will know because they will have a lean bog or a lean idle, then you are ok. Smoke and performance every time if some guy at the track says thats too hot just nod and smile. Everyone has an opinion and this is mine.

frank are you running the standard or tuned ..couldnt remember ...only reason i ask is because the standard will run a little hotter than the tuned ...when tuned ....that was a mouthfull

any one have a used or new piston for the GRP .21 they want to sell? if so i want to buy it!! i need it desperatly..i dont want a broken or scorn one..maybe one out of a slightly worn out set if its used

What brand plugs are we talking about? Was looking on amain to see, are these the OS brand? If so the p4 was the super hot . So wouldnt that be hotter than the p3. Thanks guys for aswering all of the rookies questions.

Alright I went back and looked again, and the p3 is the ultra hot and the p4 is super hot, so I pretty sure we're talking about os brand so the p3 is a hotter plug.

steve what is the tempratures where you are running ...if its 80-90 you would want a med-cold plug if its more like 50-70 you may want a medium plug ....the p-3 is the hottest plug os makes ....ultra hot .....most people run a hotter plug because of start up and idle ...when in reality you should run a plug based on what the tempratur is outside ....inmho .....not to mention a hotter plug has a thinner wire which in turn breaks easier than a med-cold plug ...so there is some trade off ...

Lately its been around 70 but I would say in the few weeks we'll be running in the 80's and then end of may to june 90 to 100 plus. So would the p3 work better in the 70 degree weather and then the p4 when it gets hotter out side? BTW I finally got the 2.0 in the dirt today with about 7 tanks on the grp and coming from a mach 427....whooo what a difference! I'm gonna have to learn a new driving style cause with the mach I was able to run it wide open on a lot of the track. love the GRP

I run P3's all day long no matter what the temp seems to work fine for me. Idles great and very few flame outs I use to run a P7 plug and had more flame outs. The P3 works great. I did not like the GRP plugs way expensive and didn't seem to last as long for me. You know the old saying, if it ain't broke don't fix it.

frank did you see my question up there for ya ...quess not ....how is the powershouse grp running ?

your probably going in the right direction ...i think alot of people run p4"s ? or at least ive seen that on this thread ...personally i run odonells plugs 97t-99t ...havent even considered the 77t 's ive got ...just to hot for my climate ....but you should be carefull about swapping brands on the grp as alot of people have not had good luck ....i will definitely agree that the grp plugs suck ass ...everyone ive seen thats come in a brand new motor has been bad ....i got a .21 sport promo kit from rcdeal.com just for a back up to the back up ...got it for 215$+shipping ...not to bad ..they had the .21 tuned promo for 270$ but im sure there all gone by now i would have bought a few of them had i had the money .....

270 for a .21 promo kit....Thats seems like a sweet deal... during break in on mine, half way through idling my tanks through on the work bench it wouldnt start up anymore. The grp plug was blown. I put in a new plug and it fired right right up. I thought it was something I did. Its funny how everyone has different preferences on plugs. A guy at my local track that has ran several Grp's swears by the Grp plug.

I'm liking the Tuned GRP so far. I'm noticing the engine is starting to run cooler as it breaks in. Have other people had the same experience? I'm right at the 1 gallon mark still using the plug that came with the engine. So far so good.

I do have to wait a full four minutes for the engine temps to come up. I've been driving about half speed on the track waiting for the engine temp. Then come in to refuel and drive the hell out of it. Slightly soft on the bottom end for my taste. I plan on going next step up on clutch springs, or even trying a low-mid pipe. I have been using the Dynamite 053 MR pipe.

Comfortable run times have been to pit as soon as the stopwatch passes 9 minutes. Then come in for fuel. This is with this soft bottom end. I'm about as close as possible on the needle setting for the LSN. The engine will get unhappy if it's leaned out more on the LSN.

Happy so far with a bit more testing to do.

let us know how the bottom end pipe works i feel the bottom to be a bit soft myself although im running an 086 pipe and thought about the 053