Smaller Pulley to compensate for high altitude. Tune needed?

[Quad4_72]

So there is a small debate going on over in another thread of mine about whether or not I would need a new tune if I went down to a smaller pulley. I am currently at a 3.5 in pulley on my E Force and only producing 5lbs of boost. I am at 6100 feet elevation. Brenspeed gave me their standard tune for the kit to make 8-9 PSI when I first installed, but it produced knocking when I went WOT. The original tune didn't produce that amount of boost either btw. It was still at around 5 psi. I assume it was just too aggressive for the altitude so they sent me a different tune and now everything is great.

So question is, would I be able to pulley down at this altitide and not need a new tune? Perhaps two pulley sizes smaller?

 

[92fiveohfox]

So there is a small debate going on over in another thread of mine about whether or not I would need a new tune if I went down to a smaller pulley. I am currently at a 3.5 in pulley on my E Force and only producing 5lbs of boost. I am at 6100 feet elevation. Brenspeed gave me their standard tune for the kit to make 8-9 PSI when I first installed, but it produced knocking when I went WOT. The original tune didn't produce that amount of boost either btw. It was still at around 5 psi. I assume it was just too aggressive for the altitude so they sent me a different tune and now everything is great.

So question is, would I be able to pulley down at this altitide and not need a new tune? Perhaps two pulley sizes smaller?

Do you know how to datalog? If you log it and everything looks good you should be fine. If it doesnt, swap back to the other pulley and/or get it retuned.

 

[Quad4_72]

Do you know how to datalog? If you log it and everything looks good you should be fine. If it doesnt, swap back to the other pulley and/or get it retuned.

I do not know how to data log.

 

[92fiveohfox]

I do not know how to data log.

Don't do it then

 

[daustin]

I do not know how to data log.

Datalogging is very, very easy. Your eforce kit came with an SCT, right? Other than that, all you need is a laptop with SCT's livelink downloaded to it.

I sent you a PM with step by step instructions.