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-   -   Arrow Racing GTR .21 Engine Thread (https://www.rctech.net/forum/offroad-nitro-engine-forum/461596-arrow-racing-gtr-21-engine-thread.html)

bigjayjay1 05-01-2012 11:31 PM


Originally Posted by Hobby Pro USA (Post 10677790)
Arrow-Racing Team Pro Modified GTR-21's now available at Hobby Pro USA.

Ryan Lopez, Corey Johnson, and Gene Hickerson have been testing this fully modified engine since December with excellent results. We feel that we have found the best possible combination of power and fuel economy for the Arrow Engines. We have tested the Losi RE-12, OS T-2060, and VP-Pro RS-4 pipes and they all work well with these mods. Fuel mileage ranges from 9-12 minutes with a big increase in all around power.

Wow would love to see the internal when you have a chance. What type gains have you seen innreference of the power band. To date their aren't any arrows running locally so im clueless with its performance stock or modded. Im familar with the OS line been running Os for many years just recently swapped into nova line.

22Racer 05-02-2012 05:10 PM


Originally Posted by Spads11 (Post 10677845)
Any chance to get one already owned modified? I have a new one sitting in the box!

I modded an Arrow recently, waiting on feedback from him. I was impressed with the motor, thinking about possibly being a dealer for them.

Rex

Crash Test Dumy 05-02-2012 06:12 PM


Originally Posted by Crash Test Dumy (Post 10671815)
I had a little trouble with fluctuating temps, when running in the main, I gained more power and not enough smoke, so I could tell it was too hot. I had 2 minutes to go so I didn't pit, after I finished I temped it at 275f:cry::cry:

I hope I didn't shorten it's life too much:eek:

I can't wait to try this engine in my buggy!
Cheers
Brian

When doing the clean-up, I found that the tank pressure tube had rubbed the flywheel and put a hole in it.:eek:
No wonder she got hot.
Thanks James, they showed up today.:nod:

Jaz240 05-02-2012 06:32 PM

Appreciate the business bro..You should be set on Arrows for at least 18 months..:sneaky:

Afun 05-02-2012 08:24 PM

So I now have 2 Arrow .21 engines. 1 in a Agama buggy using 30% nitro 11% oil Byrons, 7.0 Carb Insert, and silver + copper head shims. Using a Jammin JP3 tuned pipe.

I have another Arrow in a Hot Bodies D8T, 30% nitro 11% oil Byrons, 8.0 Carb Insert, and silver + copper head shims. Using a Precirotate MP1 tuned pipe.

Both engines have a little over a gallon in them. SHOULD I LOSE ANY OF THE HEAD SHIMS? WHAT ARE YOUR THOUGHTS ON THE CARB INSERTS?

Thanks ahead of time for your help with this.

bigjayjay1 05-02-2012 08:38 PM

Thanks for all the Pm's regarding the motor sounds like you guys have a solid motor at reasonable price tag.

twitch_1 05-03-2012 06:55 AM


Originally Posted by Afun (Post 10684515)
So I now have 2 Arrow .21 engines. 1 in a Agama buggy using 30% nitro 11% oil Byrons, 7.0 Carb Insert, and silver + copper head shims. Using a Jammin JP3 tuned pipe.

I have another Arrow in a Hot Bodies D8T, 30% nitro 11% oil Byrons, 8.0 Carb Insert, and silver + copper head shims. Using a Precirotate MP1 tuned pipe.

Both engines have a little over a gallon in them. SHOULD I LOSE ANY OF THE HEAD SHIMS? WHAT ARE YOUR THOUGHTS ON THE CARB INSERTS?

Thanks ahead of time for your help with this.

You could even go to a 6.5 in the buggy and would still have plenty of poke i found the 7 in my old agama to much and truggy i've only ran a 7 and it's got plenty of talk and top end and fuel economy is great with both

Afun 05-03-2012 08:12 AM


Originally Posted by twitch_1 (Post 10685946)
You could even go to a 6.5 in the buggy and would still have plenty of poke i found the 7 in my old agama to much and truggy i've only ran a 7 and it's got plenty of talk and top end and fuel economy is great with both

Thanks for the response. What do you think about the head shims.

BillWatson 05-03-2012 09:53 AM

I have 2 arrows, the one in my buggy had a jp2 and the one in my truggy has a jp4. Im run byrons 30% and id p3 plugs. I can't seem to get any run time out of them. I Getty close to 8 min. Does anybody get 10 min out of these engines? I need a solution, there is no way I can compete with these engines in a main where I have to pit more than the next driver. Help!

Rsickles 05-03-2012 11:04 AM


Originally Posted by Afun (Post 10684515)
Both engines have a little over a gallon in them. SHOULD I LOSE ANY OF THE HEAD SHIMS? WHAT ARE YOUR THOUGHTS ON THE CARB INSERTS?

The original VZ was designed to run a 8mm and 9mm venturi. The real question you have to ask yourself, does running a smaller venturi mean you're on the gas more? Driving WOT on a smaller venturi burns more gas than learning throttle control on a larger venturi. The tuning window also closes on smaller venturis... So if you tune in the cold dewy morning, by hot and dry afternoon, you'll have to retune.

Did you install the extra .1 brass shim the engine came with? You must run one .1 brass and one .2 aluminum shim no matter what.


Originally Posted by losibill (Post 10686774)
one in my buggy had a jp2 and the one in my truggy has a jp4.

Here's your problem. These pipes are fuel hogs.

jsp619 05-03-2012 11:11 AM


Originally Posted by losibill (Post 10686774)
I have 2 arrows, the one in my buggy had a jp2 and the one in my truggy has a jp4. Im run byrons 30% and id p3 plugs. I can't seem to get any run time out of them. I Getty close to 8 min. Does anybody get 10 min out of these engines? I need a solution, there is no way I can compete with these engines in a main where I have to pit more than the next driver. Help!

How much time on the engine? and which Byron 30% is it a 11% oil or 9% oil?
Clutch setup?????

Jaz240 05-03-2012 12:42 PM

As great as Byrons is, it is not a fuel associated with great run times. I am speaking from experience having run 6 different fuel over the last 2 years looking for my perfect match..Byrons 30/9 and 30/11 are both wonderful fuel for performance and engine protection as well as consistency but once finding a fuel that was more aggressive while still offering all the smae things as Byrons my run times per tank with everything else being identical have increased up to 2 minutes in each vehicle with every engine I own..Just an FYI

Byrons fuel coupled with JP pipes = serious deficits in your run times

Afun 05-03-2012 03:37 PM


Originally Posted by Rsickles (Post 10687083)
The original VZ was designed to run a 8mm and 9mm venturi. The real question you have to ask yourself, does running a smaller venturi mean you're on the gas more? Driving WOT on a smaller venturi burns more gas than learning throttle control on a larger venturi. The tuning window also closes on smaller venturis... So if you tune in the cold dewy morning, by hot and dry afternoon, you'll have to retune.

Did you install the extra .1 brass shim the engine came with? You must run one .1 brass and one .2 aluminum shim no matter what.


Here's your problem. These pipes are fuel hogs.

Yes. I am running one brass and one aluminum on both engines. Do you know what size the silver carb insert that comes with the Arrow is. The pipes are in question. The MP1 is pretty good, but the Jp3 is suspect. I love that Jp3, but is sucks on gas.

BillWatson 05-03-2012 04:15 PM


Originally Posted by jsp619 (Post 10687108)
How much time on the engine? and which Byron 30% is it a 11% oil or 9% oil?
Clutch setup?????

Im running the 11% abs i'm using a 3 shoe setup. Ofna flywheel with the losi steel shoes

stallen50 05-03-2012 05:22 PM

I would get a re10 or re11 pipe and get a huge increase in run times. jp pipe eats gas. alpha 0801 pipe is good too. i got 10mins easy with buggy. and throttle controll is a must to a smoother finger will gain you run times too


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