New EGT...New PSI!?!

**Silver Bullitt** · 03-06-2010 02:41 PM

So I just replaced my Bank 1 EGT sensor (such an easy install!)

Anyways, I took it for a spin afterward and I noticed that instead boosting to a max of about 7psi now I am boosting to 10.5. Vac is still 20-22 in neutral idle.

That's a happy little bonus right?

Do you think I was running in some sort of limp mode? is 10.5psi max & 20-22 vac idle ok? I am...as far as I know totally stock except for 710n's.

Thanks!

**bigern45** · 03-06-2010 02:47 PM

20 inches of merc. at idle is great.. and a bad egt will cause you to retard timing and dump fuel, to cool things down.. and you will get less boost because of..

dont know about the 10.5.. is your gauge correct?

**Silver Bullitt** · 03-06-2010 02:53 PM

Yeah It has been since I installed it a few weeks ago. Before the EGT change it was usually around 5 with a max at 7.5ish MAYBE 8. with a vac of 20-22 when warmed in neutral at idle.
10.5 is kinda in the chipped range isnt it? Pretty sure I am not chipped.

**bigern45** · 03-06-2010 02:57 PM

no.. chipped is 16 to 19 or so.. 10.. is well.. hrm.. not sure if its anywhere.. thats why i suggested a boost gauge failure. i was showing 27 holding to redline on mine.. got it to EPL.. on the dyno.. Tony's gauge showed 25... so a cheap or faulty boost gauge could mis lead you.. but.. id just be happy with it.. then if you go stage 2 and the gauge shows 20 psi .. then fo sho.. the gauge is bad... unless your n75 valve is retarded....

**Silver Bullitt** · 03-06-2010 03:16 PM

Hmmm retarded n75? Don't really know what the n75 does. Maybe I screwed it up installing the Egt? It is right there, right?

**JWatson** · 03-06-2010 05:40 PM

When Im on my stock program I spike 10 when the temp outside is nice and cool. I'd say its normal and not to worry about it.

**Silver Bullitt** · 03-06-2010 06:04 PM

How about 11 at 60 degrees. Still pretty cool I guess. Definitely a lot zippier. Just wierd because all I changed was the EGT.

**The_Jerbel** · 03-07-2010 08:24 AM

Your car was going into soft limp mode before because of the erratic EGT readings.

Most stage 1-2 chips will give you 15-18psi spike. Stock should spike to around 7psi, but could go up a few psi if the car is really healthy (no leaks, all sensors healthy, etc) if the temperature is fairly cold, especially at sea level in high humidity.

**blmlozz** · 03-07-2010 08:44 AM

Originally Posted by The_Jerbel

Your car was going into soft limp mode before because of the erratic EGT readings.

Most stage 1-2 chips will give you 15-18psi spike. Stock should spike to around 7psi, but could go up a few psi if the car is really healthy (no leaks, all sensors healthy, etc) if the temperature is fairly cold, especially at sea level in high humidity.

ditto. Stock ecu programs for 7, but may adjust it a bit to compensate for air density. More air for hotter/higher altitudes, less for colder/lower altitudes.

**Silver Bullitt** · 03-07-2010 09:03 AM

Well then. Sounds like I may have a healthy car in cool humid sea level Seattle.
I'm cool with that. :)

**Korben007** · 03-07-2010 10:41 AM

my car idles around 14-16in vaccum is that okay? I live at 6500ft though.

**JWatson** · 03-07-2010 11:07 AM

I idle at 18in in neutral and warmed up and Im at 5300ish feet.

**Silver Bullitt** · 03-08-2010 08:02 AM

Originally Posted by Korben007

my car idles around 14-16in vaccum is that okay? I live at 6500ft though.

Not sure really, but I if you are a TIP make sure you put it in neutral. For a while I was concerned about mine but then I realized I was checking it while at stoplights in drive.

**Silver Bullitt** · 03-08-2010 02:48 PM

OK so here is a question.....SO if a stock 2.7T pushes 7psi on average and makes about 250hp....and a chipped but otherwise stock 2.7T pushes 15-16psi and makes what? 305?? then what does a stock 2.7T pushing 10-11 psi make in hp? More that 7psi? Or am I just at 250 because I am (hopefully) healthy?

**blmlozz** · 03-08-2010 03:07 PM

Originally Posted by Silver Bullitt

OK so here is a question.....SO if a stock 2.7T pushes 7psi on average and makes about 250hp....and a chipped but otherwise stock 2.7T pushes 15-16psi and makes what? 305?? then what does a stock 2.7T pushing 10-11 psi make in hp? More that 7psi? Or am I just at 250 because I am (hopefully) healthy?

you're not thinking about it correctly. The air is thinner, whether because it's hotter or because you're in a higher altitude, 10.5PSI of high/hot air is the same as room temp/ normal elevation 7psi. So you're making 250hp..

**Silver Bullitt** · 03-08-2010 03:14 PM

Originally Posted by blmlozz

you're not thinking about it correctly. The air is thinner, whether because it's hotter or because you're in a higher altitude, 10.5PSI of high/hot air is the same as room temp/ normal elevation 7psi. So you're making 250hp..

I dunno.....I created a special equation to figure it out and I am pretty sure my math came out right at 645HP to the wheels.

Ok I thought 250 was still right. Its just nice to be back up in that range! Plenty good for me right now.

Thanks!