zazzn

Hey guys,

what boost can you make before you hit boost cut?

Seems I am hitting it around 14 ish PSI? I though the 2jz map was good for 18 PSI?

Kaiser

iTrader: (1)

If I remember right the cut is at about 11psi. The JDM map resolution is awful above 12psi. Mine read 18psi at 14psi.

zazzn

it must be because i'm hitting cut at 13.x and 14.

Is it the MAP or is it just that the ECU is only looking x amount of volts to cut?

I guess i'll be hooking up the emanage sooner then i thought.

Kaiser

iTrader: (1)

The MAP is limited to about 1.25 bar before it maxes out. About 18psi, but as I said it's reading that early. So I turned up the boost until it got to about 11.5:1 and called it good. No AFC or anything at this point. I'm not sure there are any parameters for boost higher than that in the programming.

zazzn

but i'm not hitting 1.25 bar before i hit boost cut according to my pressure sensor on my E01 i'm hitting 13 psi.

I'll hook up my mechanical as well but i know what i was seeing doesn't make sense cus even if it was a boost leak it's based on manifold pressure so thats why i'm wondering whats going on. I did hit 15 when i just bled the VSV valves with out boost cut? SO thats why i'm sctacthing my head.

Kaiser

iTrader: (1)

With no BCC installed you won't get there.

whatthe

Where are you taking your pressure signal from?

I hit cut as soon as it goes over 15.5-16ish

zazzn

Ok so whats the actual cut pressure? 1 bar? I'm just going to install the emanage to take care of it but I was just wondering.

i'm taking pressure from one of the manifold nipples.

xscape

yes boost cut occurs just before 14psi

whatthe

There is at least one spot on the intake manifold where the pressure you are reading won't be the correct manifold pressure. It will read a few psi lower than what is actually there.

From the clean spot on the intake manifold, I'm definetely getting cut a little over 15psi. This is the limit that I had heard for the Aristo.

DBaristo

ERM well A stock mkiv supra or mk1 aristo has a fuel cut set at 1.0 bar of boost which in laymans terms is 14.7 psi. The ECU is also only mapped to 1.0 bar of boosts worth of fuel so anything above that and you are leaning out.

zazzn

Ah ok, perfect so it's 1 bar, I'll take care of this issue soon

BTW is there a trick to use to dyno the aristo? Can i pull a plug for diag to lock it in 3rd gear? like on the mk3 supra?

Basically, i'm stuck doing the gay get it to speed and mat it.

Kaiser

iTrader: (1)

I always get to 45mph(not sure of kilo) and then floor it through 2nd and 3rd gear. The more data the better.