I'm sure most people know that boost leaks can kill power and cause drivability and tuning issues.

However it is nice to be reminded visually sometimes at just how much a boost leak can suck power out of your car.

This is a Evo 10 MR with the following mods:

MilSpec 100cell cat
Cosworth Drop-in air filter
Nisei hot side intercooler pipe upgrade
Factory ECU (no tuning yet)

Dotted lines are baseline with a boost leak, solid lines are after fixing boost leak. Amazing what a good boost leak can do eh?



So far, every single Evo 10 that has come through the shop with upgraded intercooler pipes have had boost leaks. Remember to properly install and tighten the clamps!

 

cool thanks, thats good to know

 

Interesting to see it on a graph like this, do you have a before & after graph of the boost?

 

I'll try to print it out this week.

Boost increased after fixing leak and AFR's went leaner.

 

Where are you seeing the leaks the most? At the firewall? At the FMIC?

Are most people installing the clamps loose or tight?

 

Almost always at the coupler between the upper pipe and the top of the FMIC.

Too loose.

 

Could it be a loud whistling sound indicative of a boost leak?

Maybe someone can figuratively point out in a picture where to tighten em.

Thanks!

 

Yes any whistle sound is most likely a boost leak. Induction sound is lower pitched

 

can you point out which areas to tighten? maybe an illustration of some sort?

 

Did you tune this car after? What's the final dyno for it?

 

Just look at your front grill. Just to the left of the mitsu emblem. There's the coupler they are talking about.

 

Now that this thread is up, we'll probably see people doing the opposite now. Getting T-bolt clamps and tightening them too much and deforming the piping to cause a leak

 

Any way to test for leak other than checking by sound?

 

That is a good place for a leak with out the IC pipe blowing off because the top IC pipe is bolted down in that area. So yes I can see if you did not tighten that clamp enough that it would leak alot and not blow off.

 

Good way to see a leak is get some soapy water run on area with possible leak see if it makes bubbles. Cheap leak test. Not 100 percent, but it works if you dont have any fancy equipment.