about to go from 10psi of boost to 15psi what do i need to change?

[rocketpony434w]

okay im about go from 10psi of boost to 15psi on my 88mm turbo. i've got the tune good on 10psi, so i wondering what changes will i need to make to do this swap, or will the power valve just open more and do the work for me?

[70 bird]

Try it and find out!   Keep an eye on your wideband. You may not have to change anything but all set-up's are different.

[TexasTwins]

If you can, go to 12 or 13 psi and see what happens.

[blown385]

I would also put some jet in it .    You can always take it back out .   

Dont forget to pull some additional timing .

[franktf]

I would also put some jet in it .    You can always take it back out .   

Dont forget to pull some additional timing .

+1, better to be safe then sorry.....

[dentfix]

434w on 15psi probably your underwear  lol

[SprayedSDime]

'bout to find this out myself in a day or so. Well, I'll be finding out how much boost "a few rounds in the wastegate set screw" is. Right now I'm at 32* locked pulling 2.5* per pound up to 20* total pulled at 7-8psi. I'll leave the timing setup where it is since I don't think I can really go much less than 12* and my plugs all show black and no signs of detonation and my wideband is reading mid/upper 10s at WOT. Hoping for 13-14 psi 

[rocketpony434w]

'bout to find this out myself in a day or so. Well, I'll be finding out how much boost "a few rounds in the wastegate set screw" is. Right now I'm at 32* locked pulling 2.5* per pound up to 20* total pulled at 7-8psi. I'll leave the timing setup where it is since I don't think I can really go much less than 12* and my plugs all show black and no signs of detonation and my wideband is reading mid/upper 10s at WOT. Hoping for 13-14 psi 

what do u mean my the set screw in the wastegate?

thanks for all the input guys

[SprayedSDime]

I have a Turbonetics Racegate 42mm wastegate. It has a set screw with lock nut on the top of the wastegate that you can use to put preload on the wastegate spring/valve. Should get a few pounds of boost out of that. The downfall is it has been rumored to limit valve travel creating boost creep in high gear. We'll see...

[turboboy4548]

You will definatly have to change your underwear...

[AlexL]

So?

Are you going to need to ask Santa for some underwear or a set of pistons?

[botietr]

I thought about this for awhile.wondering myself..besides the obvious pulling of more timing shouldn't the fuel/carb be ok.

My thought,and i may be wrong since this is all new to me also(1st time blow thru) more fuel pressure and more pressure from more boost should push more fuel through the jets,richening as boost increases.right? wrong?
so if that is right,less timing and leave the fuel supply alone?
unless your jets/PVCRs aren't big enough to supply  enough fuel at that boost level to begin with.
talk to me.

[blown385]

My thought,and i may be wrong since this is all new to me also(1st time blow thru) more fuel pressure and more pressure from more boost should push more fuel through the jets,richening as boost increases.right?

In a perfect world , yes .

But most carbs do not work perfectly .

Going from 10 to 15 is a big jump .   I would add more fuel with such a big jump . 

If it was me I would just add 1psi or so at a time . But its not that simple for blower guys or guys that run on spring pressure alone .

[SprayedSDime]

Would it not, in theory at least, get richer for those that have the HSAB's blocked? I thought the purpose of those was to prevent an increasingly rich condition early on.

[pontiac_baron]

block the HSAB's

or maybe just block one of the emulsion holes in the metering blocks (depends what is already done to your carb)