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View Full Version : Product Review: GrimmSpeed PnPnC Headers!!!


UP2MTNS
08-19-2007, 06:01 PM
Alright folks, I've had these on my car for a few weeks and a few thousand miles now, and its time to report.

First, if you don't already know, PnPnC - Ported and Polished and Coated
Link to product:
http://www.grimmspeed.com/store/index.php

Install is very straight forward....take your headers off, and put theirs on.(ha!) A few hints:
1) Start by removing the O2 sensor that's inside the right tire, just below the uppipe, but on the topside of the header. If you can't get that off, don't start. It helps to have an O2 sensor socket.

2) You'll want to put your heatshielding back on, and there are a lot of bolts/clamps, so be careful when removing, and mark locations/bolts if you have to for when you put it all back together. Once you have the sensor off, start from the drivers side and work toward the uppipe.

3) you can do it all with basic hand tools (except point #1) and you'll also want a 10in. socket extension.

Results:

I could definitely tell the difference in throttle response and all the way up to 3500 RPMS via my butt dyno. After 3500 its a little harder to tell just by 'feel', but I'm sure it looks good on a real dyno.

My turbo comes on earlier as well, for my engine, probably about 400rpms quicker. Specifically, in a 2nd gear pull, you could really feel the turbo kick in around 3500 rpms, now I feel the same kick about 3100rpm.

And the best part, 100% bolt-on, NO protune necessary!

Let me know if you have any questions...


OH, and customer service/ordering from GrimmSpeed is really good too, great vendor to deal with.

sebhockey
08-20-2007, 12:19 AM
Do ya still have that nice boxer rumble?

UP2MTNS
08-20-2007, 07:44 AM
Do ya still have that nice boxer rumble?

yeah, in fact, my sound didn't change at all.

OH, should mention that i'm still on the stock Up Pipe, so I'm probably not getting all of the benefits.....yet. :twisted:

lorenkb
08-20-2007, 09:12 AM
How is a re-tune not required? If you are changing the airflow through the turbo enough to spool 400 rpm's sooner what is to keep the boost where it needs to be (and from not overboosting)?

I know just enough to confuse msyelf but here goes: The boost level is controlled through the wastegate. What I don't know is whether or not the wastegate is on an open or closed loop control: if it's closed loop (wastegate is actively controlled to mantain a ceartain boost level) then I can see how a re-tune would be unncessary. If it's just a lookup table though you risk flowing more air through the turbo than the wastegate is setup to deal with.

Either way I'm still looking forward to getting this done. One of these days...

UP2MTNS
08-20-2007, 09:29 AM
How is a re-tune not required? If you are changing the airflow through the turbo enough to spool 400 rpm's sooner what is to keep the boost where it needs to be (and from not overboosting)?

I know just enough to confuse msyelf but here goes: The boost level is controlled through the wastegate. What I don't know is whether or not the wastegate is on an open or closed loop control: if it's closed loop (wastegate is actively controlled to mantain a ceartain boost level) then I can see how a re-tune would be unncessary. If it's just a lookup table though you risk flowing more air through the turbo than the wastegate is setup to deal with.

Either way I'm still looking forward to getting this done. One of these days...

I'm in no way an expert on tuning or fully understanding the intricacies of our turbo system, but the ecu tells the turbo what boost to hit......the turbo spooling up to that mark is still dependant on exhaust flow through the hot side. this allows the hot gasses to stay hotter, and therefore spool quicker to that mark.

Its not about hitting higher boost (although, boost creep could be an issue), its about getting there quicker, and by getting there quicker, you have better throttle response across the rpms, but most noticeable at lower RPMS.

sebhockey
08-20-2007, 10:49 AM
You'll have to let me check it out since practically right next door now.

UP2MTNS
08-20-2007, 11:07 AM
You'll have to let me check it out since practically right next door now.

yeah, i'll let you take it for a spin....its no STI, but its pretty fun to drive with all the other crap I've done.

sebhockey
08-20-2007, 11:13 AM
Cool, let me know when, I'm on leave till the 10th, so I'm free just about anytime till then.

409industries
08-20-2007, 11:17 AM
I really dont think that creep would be a problem since from what i have experience in the past i only had creep issues with a different TBE... Since the exhaust manifold is before the turbo, overboosting could be a problem, but i never had any more issues with creep after getting my AccessPort.

Creep is a problem when the stupid wastegate doesnt let the excess boost out