Determining if/where a boost leak is

[Kip2MyLou]

Damn, I really need to tighten my claps. Haha. That's good stuff.

 

[AMontgomery]

What tune/mods are you running with those results? Timing advance is low boost is average but your torque is through the roof

 

[dyn085]

Stage 3 with Freektune, 93 octane.

 

[AMontgomery]

Gotcha. I was wondering.how your torque got so high.

 

[AMontgomery]

Here's a pull I did at lunch. Swapped to the 93oct stage 1

 

[J2FoRS]

If we have a boost leak, what would be the symptoms?
I have NEVER seen over 20.5 PSI on my AP. Ever. But everyone else on Stage 1 is throwing up numbers in the high 21's or even 22.45 I saw today on someone's. The weather is colder now, I used to think I was just getting heat soak in the IC in the summer but I tried numerous times over the last few days and tried to do data logs and stuff and my PSI ranged from 19.46-20.34 over 6 runs over 3 days.
What am I missing? If there's a leak would I still see that high? Would it surge? It still comes on smooth and clean. Getting frustrated

 

[dyn085]

What is your boost reading at idle with the a/c off and fluids at operating temperature?

 

[J2FoRS]

What is your boost reading at idle with the a/c off and fluids at operating temperature?

Like the negative numbers?? Kicking around -10.4 to -9.8 ish? Like it's not the same steady I guess...is that an issue?

 

[dyn085]

That's not an issue, and those are numbers indicative of having a good seal. I wouldn't worry about it.

 

[J2FoRS]

So if it's not a leak, is there something else I should be looking for to trouble shoot my lower boost numbers? Or is my car just a weakling compared to others.

 

[Etyrnus]

Altitude difference? Have you dynoed stock vs stage 1?

 

[dyn085]

You can take some datalogs and post them up if you want. I don't recall the stage 1 settings offhand so there's little info I can give you at the moment.

 

[CivicAssassin]

I was thinking altitude difference, as well. If you look at it from a torque targeting point of view. Guys in higher altitudes would need more boost than guys on the gulf coast, to make the same power. My theory, anyway...

 

[CivicAssassin]

Oh....Is the negative pressure check a proven way to judge boost leaks? If so, that would be a nice and easy way for people to check on it.

 

[dyn085]

The best way is always a pressure-test, but a healthy engine should see somewhere between 17-22 in Hg at idle when warmed up, roughly. Because the AP3 doesn't read vacuum, that converts to roughly -8.3 to -10.8 psi. If you aren't reaching at least -8.3 then there is a possibility of having a leak.

Granted, having less vacuum at idle can be an indicator of a bunch of other mechanical problems, but considering the young age of the platform it is less-likely that something else would be the cause.