SC Apex @ 5psi working awesome couple questions wanna go 7

[TurboJamie]

Apex is dialed in @ 5 psi really well and looking to go to 7 psi. Absolutely awesome sled and nearly untouchable by anything else around and getting mint gas mileage but more = more fun. We had it up in northern Ontario this weekend and put 500 miles on it torturing the piss out of it long hard pulls in 4' deep snow. Long runs on railway lines and lots of diff throttle positions it works awesome. Aside from running octane boost and killing my WB sensor from LEAD!! I have to run a new sensor this week and replace a whole bunch of studs the thing snapped off from the excessive jazzing the track took.

I want to go 7psi and just have a couple reliability questions are my fuel trims going to change or remain the same as now? Not that its a big deal but I would like to keep my mileage I am getting. I have a buddy that did some tweakin to an old 809 tripple and its awful close but its near 200 HP right now so thats expected but I need to kill it bad so it seems 7 psi is the way. Any other downsides besides the smiles?

Couple pics here you guys.

 

[TurboJamie]

Another pic in Elk Lake.

 

[BlgsRX-1mtn]

I don't know if your fuel trims will change or not on the APEX motor. I know on my RX-1mtn; I dialed in the carbs on the low boost underdriven pully configuration using pump premium. Once the A/F readings were dialed in I just switched the pullies for more boost. My A/F readings stayed relatively close to what I was seeing on the low boost setting (were in the range so I made no changes).

My clutching was a little low for RPMs also until I switched to high boost. I went from 9600 on hardpack to 10,500 if I hold the throttle to the bar. It definately hits the 9800 target though when climbing in deep powder which is what I wanted. If you're clutched for 5# and turn it up you might find the rev limiter.

Also, I thought our SC kits went to 10# from 5# when switching the pullies. It was my understanding that 7# was only if you have a 1:1 pully ratio. Are you running a boost guage? If so could you report what the actual boost is when running overdriven vs. underdriven? I know the differences in clutching and altitude will make some difference but it should be fairly close.

Jim

 

[Mavric]

Hi a7m266d,

Your GT seems to be dialled in great.
Could you please let me know the numbers
you are using on your fuel controller in
modes 1 to 6.

thanks

 

[TurboJamie]

Im running a boost gauge and the pullys for 5-10 psi Mac also has a set for 7-14 psi which is what I just ordered. Appearantly 7psi is pump safe and around 210 hp ish. Which is what I need. Mine just barely holds the 5 psi at WOT so it should be mint with the 7psi pullys.

I have not tried to switch to the 10 psi setting frankly I don't want to go there and not be able to stay there haha I ride up north alot of semi questionable fuel so I need pump reliability.

I will get those fuel trim numbers for ya tomorrow or the next day I have the sled tore apart because I took out the WB sensor because I used some heavy octance boost running 87 octane fuel and the lead in the junk killed my sensor.

We pretty much rode it on the bar in northern ontario for lots of 100 mph stretchs for minutes at a time with zero issues.

 

[Mavric]

It would be great if you could get me those
numbers as I ride mainly in northern ontario
and live Queensville so they should work great.
I hope my supercharger is installed by tuesday
night and I can test it on Wednesday.

thanks again.

 

[TurboJamie]

Queensville Im in Ballantrae Just North of Stouffville.

 

[spray25]

You mentioned octane boost in your first post. Be very carful most of that stuff does nothing to actually raise your octane.

 

[TurboJamie]

You mentioned octane boost in your first post. Be very carful most of that stuff does nothing to actually raise your octane.

I was using VP Fuels C5 Octane Booster however I just ordered the Parker Knock Sensor so I am just going to work on 91 Octane and the Knock sensor to tune from now on. Or 100LL I have 3 45 gallon barrels of that for the airplane at the cottage I can use to mix with pump fuel.

 

[Skydog]

You are mixing race fuel to run 7 psi??

Skydog

 

[TurboJamie]

No I was way up north at my place and the lodge only had 87 octane fuel so I was mixing 100 LL with that just to be safe. I was also adding C5 to 91 for safetly but I don't feel its necessary and now that I ordered the knock sensor I should be extra safe.

 

[Skydog]

Sounds good buddy!!

 

[slow]

7 lbs boost

ran 7 lbs boost in Yellowstone for over a week and once dialed in ran very nice. One thing I found was the Attack would hit 10,500 with out the hood but would only slowly hit 10,000 with it on? Talked to Mac and I removed the small hood grills and this cured the problem
Slow

 

[sledheadgeorge]

No I was way up north at my place and the lodge only had 87 octane fuel so I was mixing 100 LL with that just to be safe. I was also adding C5 to 91 for safetly but I don't feel its necessary and now that I ordered the knock sensor I should be extra safe.

Where are you getting your knock sensor from, and what kind is it?

 

[TurboJamie]

Its from parker motorsports I found it on this site.

Thanks for the tip on the hood I just run a big piece of foam ontop of the ic to keep the snow out.