Seeing less boost after race pipe install.

[Domino81]

I'm only seeing around 13 psi after my racepipe install. Feels like it pulls harder beyond 4k, anyone else notice this?

 

[SallySpeed3]

Hmm my first thought was maybe an exhaust leak but not sure if that would cause boost loss. Our cars are load based, so with this colder weather it's possible that you're hitting load cap even with lower boost.

 

[Domino81]

Explains this ...load based business?

 

[SallySpeed3]

Well I'm hardly the person to explain it, but I think I know the basic gist of it. Our ECU has a set maximum load which you can basically think of as being our.....volume? lol. "Ours go to 11" Anyway, think of it this way. Going wot = 10 out of a 1-10 scale. So you floor it, the ECU says ok I need to look at how much air, air temp, how much fuel, how much boost, timing, etc. to arrive at putting out a "10". A stock speed 3's boost is like 15.6 i think but thats under average/normal driving conditions. So its possible that in the circumstance when you saw your boost only going to 13 that your ECU was able to achieve max load by only using 13 lbs of boost. But I would still try and rule out any leaks or such.

 

[Domino81]

Doesn't the Cobb AP/HT correct this?

 

[SallySpeed3]

Not sure about the hypertech but I know COBB raised the max load cap in their last batch of maps

 

[Darth Vader]

You'd know it if you hit the load cap, as the engine bucks mightily and your face hits the wheel.

Look for leaks intake side, even the stock IC clamps work loose pretty regularly, at stock boost. You are now making the turbo work harder and thus putting more strain on the intake side sealing at those points.

HT has higher load caps than stock as well.

 

[Domino81]

I'd think removing the extra restriction of the 2nd catylist would remove some of the workload of the turbo.