MTNTK Turbo Axys: clutching tips? Boost psi?

[jeffthebuilder007]

What primary weights and secondary clutch spring/helix/settings you guys running? My '16 Axys with 163" 2.6 track currently has 10-74's and stock secondary set up; only running 4 psi boost and still revving to 8400. Riding at 5000-6000 elevation.

And what boost psi are you running at different elevations? My Bully Dog is showing 4 psi on hard pulls (wastegate is at factory setting). Currently running 91 non-ethanol plus 3 gallons Av Gas for insurance and runs perfect. Looking to turn up the boost to around 7-8 psi but want to copy what your doing so I do not waste money on weights or helix combinations that might not work

 

[Tewstroke]

I am also running a '16 Axys, 163".

I'm running the Polaris 10-74s. Stock secondary. The black primary spring that Shawn sent with the kit (140-330)
5000-6000' - (Tampico-Darland Mt, Angle Point, Rimrock Lake - Section 3 )

9 psi on AutoMeter liquid-filled gauge. 50:50 Av /Premium. I'll probably go less on the AV gas. I'm just getting used to not using 100% Av Gas from piggyback turbo systems. The Bullydog tuning is pretty impressive.
Hitting 8400 rpm climbing today. I've shortened the wastegate rod some to get to the 9 psi, since it was around 6 psi the first time out.

A physical boost gauge may give you more direct/accurate feedback. It seems odd that you would rev 8400 with 74s at only 4 psi. I question the reading from the Bullydog gauge.
You might run it past Shawn Davenport at MTN TK. He is very good about getting back to customers.
I've only been out three times, so I am learning this system as well. It sure has been nice to just ride and not be tuning a piggyback box.

Darrell
Yakima, WA

 

[jeffthebuilder007]

Thanks Darrel, good info.

I did some data logging on several hillclimbs last week up at Ahtanum and then sent the mini sd card to Shawn so they could see how the sled is running (I could not get the files to download from the card to my pc). My wastegate rod has about 8 threads showing from the end and never saw over 4 psi on bully dog; maybe you are right and this is not an accurate reading for some reason.
Jeff

 

[Tewstroke]

Good luck!
I'll be interested to hear what you find out.

Darrell
"Tewstroke"