The shoulder is not an issue. There's plenty of clearance. That is good thinking though. Today was my first day competing with my .21 in my Losi 8 buggy. I've owned most of the major manufactures and this engine is the best of everything. I've got power that is more than enough, nine minutes of runtime in my main, and it's easy to tune. Using the os p3 and the Jammin' JP3 pipe. Also have a 6.5 carb restrictor in it now. Trying to make it easier to drive and going to the best runtime I can get. It's still very tight and I'm getting nine minutes. A few more race days should improve my runtime even more. My temp is 185 consistantly. Can't wait to get the GRP pipe in a couple weeks.

??????'s

I did not shim the head on my GRP .28
I asked drake at rev one day if i needed to he said nope just run it
I ruined a p5xs when i started nitro last year ....so i worry a little


What ya think shim it or not BYRONS gen 2 30 percent is the fuel i run

I was way off with the decimal, I appologize. I'm actually shimmed out to .5, It came stock with (1) aluminum .3 and (1) copper .1 already installed. I installed one more for a total of .5. Would what you describe above still be an issue with this clearance?

No, what you have sounds correct for 30%. I was just making sure with the clearance numbers you had.

You could be onto something regarding the P-3 plug. The only variable that changed from the time I took the engine apart on Friday night and drove it at the track on Saturday was that I changed the glow plug from a GRP #6 to an OS P-3??
It was around 90 degrees out (pretty warm), but the temp at the glow plug was consistently around 185-190.

I would check with GRP about repairing that engine. I would also not use Nitrotane for break-in. I would use a high oil/low nitro fuel first for break-in.

Does the engine need a shim added to run 30?

I guess not.

http://www.neobuggy.net/modules/newb...=ASC&start=220

Some add the shim, some don't. I have seen engines run without the added shim, but I prefer to add it on all of my engines.

It probably will be OK without the shim, but don't forget those guys get their engines for free, and aren't really concerned with week to week longevity. As long as it makes it through the main, for them it's good to go.

I just bought a GRP engine today.

This thing looks really sweet!!

awsome, now if we can just get steveja to get a decent engine

Yeah, I don't see that happening. Steve is a cheap @ss!!

BTW, I might need your advise and tips on breaking this thing in. Also maybe your tuning advise.

I think the losi's are going to be hard to beat this year!!

I just wrapped the head and heat cycled it two tanks on the starter box and then another two tanks putzing around my driveway. After that I ran another two tanks pretty rich at the Plex and then started to tune for power. This engine likes to run really cool so tune by power and exhaust smoke more than by temp. Opening week at the Plex the hottest my engine got was 210, steveja pulled his gotech off at 280 when I was temping mine I also put an O.S. P3 in mine after break-in, seems to smooth out the idle compared to the cold plug that comes with the GRP.

Matt, have ya had the chance to compare the GRP to another motor - power wise? I'm curious to see how it matches against my EB Modded V Spec. I'll be starting break in on my GRP tomorrow when the engine mounts come in.

And I love that sig. Ironically, I got yelled at on the driver stand this past Sunday when I was lapping a guy in the main for the 4th time. He yelled at ME to get out of the way!