Noxlupus

Hey guys... So I had the local dealership run a boost and compression test and here are the results:



Compression Reading:and Boosting of 13.5 PSI.


My current setup is all stock minus the cats; running stright pipe. Could this account for the increase in boost? In addition, do I run a risk of blowing the motor if I go WOT with this amount of boost?

Thanks,

Heisenberg

iTrader: (3)

Yes. Chances are you will blow your motor.

Noxlupus

Thanks BackyardSog... they were telling me that there's no real chance of blowing it - other then normal wear and tear.

GoodfellaFD3S

iTrader: (213)

Those are really good compression #s. I would find out if they did the test with the car warmed up properly, and what the cranking rpm was (should be 250).

I recommend purchasing a highflow cat and getting rid of the midpipe. if you have stock intake and ic, you should be fine on the stock ecu as long as boost is around 10 psi.

dgeesaman

iTrader: (7)

13.5psi is too much. 11psi is what I consider a maximum, and even then you're relying on the quality of the gasoline and that the injectors are working perfectly.

Add some restriction to your exhaust and boost should come down some. I agree with rich, replacing the midpipe with a high flow or even stock cat will keep things much more under control and the car won't be half as loud and smelly.

Dave

Noxlupus

Thanks Rich, Dave!

I'm planning on adding a custom intake, keeping the stock IC for the moment though; slated for installation on the 28th along with new radiator and bigger oil coolers. I'm also in the process of installing a PowerFC should have it installed by tonight. Do you still recommend adding a high flow cat? I've been reading up on the PowerFC, but I'm still green so, not entirely sure if I'll be able to control the boost via the PowerFC.

As far as how loud it sounds, it sounds fine I think, but yea the smell make me dizzy in a few mins! LOL

I'll call them up and find out how they got the compression numbers, as well as the cranking RPM. By the way, what use if this information - the cranking RPM and how they tested the compresion?

Gianny

Heisenberg

iTrader: (3)

The PowerFC base mod map that comes loaded when you purchase the unit should be fine for the modifications you have done with 10psi. I reccomend that you restrict your exhaust a little with a cat or restrictor plate. Once you do that you should have your boost creep problem under control. If you want to run the higher boost and keep the current exhaust, you can try to control the creep by porting your wastegate and getting a boost controller.

You can not control boost with the PowerFC unless you get a separate boost controling unit from Apexi. However the PFC is known to read boost levels incorectly and the boost control unit isnt very popular at all.

Noxlupus

So by the sounds of it my best course of action would be to get a high flow cat installed in order to restrict my exhaust causing an increase backpressure thus controlling the boost creep; i.e. reducing my boost.

I believe I understand. Thanks again!!!

Noxlupus

So, after reading 3GRX7’s thread, OK OK… I’ve searched, learned, and understand, but I have a question about exhaust: I’m now confused. I was convinced that what I needed was a high flow cat to control my boost creep; I thought that’s what I had from what I read on here… but after reading said thread, I’m under the conclusion that I might just be over boosting. If this is the case, will a high flow cat solve the problem?

Okay, here’s my setup again so you don’t have to scroll up.

Everything is stock with the exception of the following: PFC, Downpipe, Midpipe.
I do have stock muffler.

Upcoming mods (installing them next weekend): Custom intake, J-Spec Y Pipes, and possibly Greddy’s Titanium Exhasust (if it gets here in time).

Giving the upcoming mods, should I still go with the high flow cats to solve my problem of either over boosting, or creeping (which ever the case may be) or posting the WG? Also, what do I have? Creeping or Over boosting or are they the same? I’m really confused now.

dgeesaman

iTrader: (7)

Overboosting is different. Overboosting in the sense of an FD with a few bolt-ons is when you install a couple bolt-ons and you're using the stock boost controller. The extra flow causes the boost to go up, and the stock controller makes no adjustment to restore correct boost. This is where the old 3-mod guideline comes from - about the 3rd flow mod on average is where you start going above the stock 10psi. The PFC does give you some ability to tune the boost but you're still stuck with the limitations of the stock boost control hardware, so it may solve the 13.5psi problem now but it won't when you add more stuff.

The answer, at least for the next couple bolt-ons, is an adjustable boost controller (manual/home depot or electronic).

Boost creep is what happens when you install the boost controller, adjust it wide open, and still the boost keeps going up. For short boost runs you usually will see the correct maximum boost - it's when you get into hard throttle for a few seconds, and the longer you stay in it, the higher the boost goes (hence the name creep). It never stays at a solid maximum. That is a problem of mismatch - too much flow for too small of a wastegate. The solution is simple - reduce flow or increase the wastegate size by porting.

Don't install any more mods until you get a boost controller in there. Installing a high flow cat will reduce flow compared to that midpipe, but if you install the y-pipe, muffler, and intake, you'll be back where you started or flowing even more. To be safe, you should get the boost set using a boost controller, and install each mod (in the order of importance to you) and take a good test drive and re-tune your boost controller for 10psi. If at some point you notice the boost controller won't hold a solid maximum boost value anymore, you're getting boost creep. Then you need to decide whether to restrict the flow or port the wastegate.

Dave

GoodfellaFD3S

iTrader: (213)

The main thing you will need to keep boost under control is exhaust restriction, that is where the high flow cat comes in.

Also, don't forget porting the wg is not an easy task---the turbos have to come off the car, which sucks.

Noxlupus

Now, when I had the boost reading done it was with the stock ECU. I just installed the PFC last night. So I probably should have another boost test done; right? Also, I've been reading up on the PFC, but I have no clue where to begin in hopes to control the boost. I'm a bigger newb when it comes to the PFC.

So porting the WG is probably not my first option since I would be doing the work myself...

When you say don't install any more mods do you mean from what I have now, that is: MP, DP, PFC, or do you mean from the ones that are scheduled to be installed next weekend? Does it include the HFC?

Noxlupus

Hey Rich, I asked about how they did the compression test, they said that they allowed the car to warm up before they ran the compression test. They were unsure of the cranking RPM. Which high flow cat do you recommend?

On a slightly different topic, what's a normal knocking level? My PFC is reporting a peak of 21.