I am using the VZ Speed crank. It's too different from the standard VZ/Arrow to even compare.

I am still curious how the crank has different timing over standard VZ?

Forgot to mention the porting of the standard VZ sleeve and Arrow sleeve is slightly different too. Look at the main port between the two transfer ports. It has different dimensions (intentional? I don't know... Maybe they just couldn't easily duplicate it).

Maybe they actually had enough Integrity to not duplicate it exactly.

1 1/2 gallon with no mercy so far so good

Did the same, she was ready, truly ready to race at the 2gallon mark

Until 2 gallons, I was struggling to make 7.5 mins. Probably can get 9 easily now.

I think they are trying to make it better........what's lacking in the Vspec.
In my opinion, the engine is just different from a Vspec.
Not a exact clone which many think so.......which I thought it is similar until I ran the engine.

As the performance is way different.

i'm the same as i feel that this motor has a way smoother bottom end but still has that top end scream that i liked about the vspec but just hated the bottom end...

twitch_1,

maybe you can try this and treat it a whole learning experience.
retract the msn needle. one full turn out. tune your lsn with to get the low end in.

your engine will be a totally newly transform performance.

No i meant i hated the vspec bottom end but love the bottom end of this motor this is the best motor i have used to date

I would think so. But that's only me and you.
I have a couple of guys running it but complained the way Arrow's bottom.
Way too smooth and doesn't have the ooh and ahh......the punchy characteristics.

Well those reading. The Arrow definitely have it. Retract the MSN screw by a full round and tune the LSN and HSN to it's max performance.
And you will be totally surprise........

However, i have try a couple of pipe......but I find only the OS 2060 pricey pipe, gives it overall performance in terms of runtime ( 10 mins ), low temperature, reliability, and etc.
The Orion pipe too gives good performance but lacks the runtime. The Losi pipe is way off. Novarossi is good too but similar to Orion pipe - lack of runtime.

All these pipes were tested on a high speed / huge track.
Once we get the engine to a smaller track......the runtime is just ridiculous.......

Are you saying to turn the mid speed needle one turn out from flush?

Then tune low and top end? Reason I ask is mine runs great, bottom really smooth but the bottom needle is about 1 -1.5 turns out from flush.

Thanks

Just sharing.

From my guess, your MSN is about flush. That's explain your LSN is out. Nothing wrong. As long as you like it SMOOTH. I too like it smooth.

Reason:-

It is a lot simpler to drive. Very consistent lap times.

But on some track, especially the short ones meaning.....not a lot of run off distance between the jumps, you need the engine to be really responsive.

In your tuning, you might. I mean you might. Find it is sluggish. By moving the MSN needle out, it increases the engine responsiveness. Making the engine response to your throttle input. Allowing you take the jump with enough throttle input. Not over and not under. Over, nose high.....( brake to bring it down......) way under nose down.........( you need to throttle hard ) to get it back flat........therefore it will affect your confidence in those tricky jump.

Then you may retune it with the MSN out.....and LSN will be more inward. Just + and - but the engine comes alive in these tracks.

I have 2 carbs/engine.......ready. One for huge track with smooth jumps.....and One for small, twist and jump track.

If you get what i mean.

The hong nor pipe on this motor are good also i run the 2080 with good reliable run time (11 mins) and performance if i want more snap i go to the 2047 more punch with out hurting the runtime to much (10 mins)

Ae 2039 for run time and top end
2013 orion for bottom

The inner parts are long lasting,i got 5 gallon on both my GTR,still performed great!

I have 3 Arrow Gtr and all performed well. No flameouts at any of the races. I dial in the LSN till it shows signs of a leaning, then back out the mid range needle by half a turn..
The engine performed totally different..
I did the same for all the 3 Arrows..