What should I do?

Veh: 05 lgt w/ 85K/auto trans/Borla CBE and KN SRI, runs great

Used as: DD, mostly commuting and will not see the track

Want to: Go stage 2 (AP/DP/maybe UP)

Should I:

1) Keep KN SRI

2) Go back to stock

3) Either of above and also install UP(is it necessary?)

 

I've read the comments here, lil confused, need some experienced input. Thanks in advance!

You want your minimum mods to be:

 

-Catless uppipe. You can just remove the catalyst material from yours or purchase a catless version)

 

-Upgraded Downpipe You can just remove the first or both cats from your stock setup and reinstall, or you can choose any aftermarket downpipe. I prefer bellmouth and catless. Check out CNT or mspranks group buy for a good price on this.

 

-Tune. This is most important. You can get an Accessport which has an off the shelf map or you can choose open source if you have a laptop and are competent with a computer. In either case, you should get at least an etune (emailed tune) that is more custom to your car. The AccessPort costs a bit more but is easier for most people.

 

An intake is fine but needs to be accounted for with a proper tune. Any catback is also fine for use but neither of these is required for a typical "stage 2" setup.

UP, DP for sure. Options are, in order of $:

 

0) Do nothing, not even the UP/DP. But where's the fun in that?

1) UP, DP, keep the SRI, and get tuned by a professional using EcuFlash (so-called "open source" tuning)

2) UP, DP, stock intake, buy an AccessPort, use the included stage-2 tune.

3) UP, DP, keep the SRI, buy an AccessPort, get tuned by a professional.

 

For options 1 and 3, you can add as many parts as you want, since you're going to get tuned for them. If your tuner prefers aftermarket boost control solenoids, I suggest getting one. You'll probably get a little bit better boost control that way.

 

I suggest adding a TMIC for options 1 and 3, since that will allow the tuner to use more boost without popping the ends off the stock TMIC. The tune that comes with the AP is limited to about 16.5psi and I suspect that the stock TMIC is a big part of the reason for that.

Thanks for the replies. Just wondering, does the Cobb AP compensate or learn, ie if I kept the KN SRI. Is the stock vs SRI "discussion" on a basic stg 2 because the car may run lean on a aftermarket air intake? I am assuming that a off the shelf prog/cobb is prob programmed more on the rich side to be safe. Correct me if Im wrong. I ask why? coz I like the KN SRI but when I upgrade I don't want to hurt the engine etc. Again, just a DD, won't see the track. I have my Crotch Rocket to get my jollies on

The AP off the shelf map is a bit rich, though leaner than stock from what I understand. In my scaling of various different intakes I've noted that most are off close to 10% in the upper maf ranges. On stock fueling , that would put you around 10.6 or so afr and should be safe. The problem comes in when you have an already agressive open loop fueling table and then add an intake. If you're tuned for even 10.8 afr then an intake could put you into the 11.8+ afr range and that is too lean.

 

Personally I would skip the off the shelf map even if you go with the Cobb AP. If you want a reliable quick daily driver, get a reputable tuner to get you a pro/e/dyno tune that accounts for the intake as well as any other mods and let him know what you're looking for.

 

You can skip the TMIC if you go with a reasonably conservative tune in the 16-17 psi range, but I would tend to agree it's worth getting for piece of mind. My stocker held 18psi for a while but was clearly separating. I picked up a used oem TMIC and did the JB Weld trick that several here do and that didn't hold much better and was cracking within a week.

 

If you give an idea of what your budget is, myself or someone else could recommend a more exact mod path for you. Also I notice you're in New England. You could consider just getting an up/down and taking it to EFI. They can do an open source tune that wouldn't require you to buy an AP or a Tactrix/VAG-COM cable (open source). Most will agree that you should still have your own cable to check logs now and then and be able to return it to stock though.