Donpipe/UP PIPE questions.

[G.T.Subie]

Well I recently ordered an up pipe and plan on installin but relized it looks like a lot of work. I came across a used DP and figured if I was going through all that work I should do both.

My question is I don't have an AP, would this just be causing problems with CEL's? I Know about the UP resistor, but what about the DP?

Also what are some PROS and Cons of a Shorty vs a full DP?

[schwinn]

I started with just the Crucial UP on my car, had no issues (other than repeating exhaust leaks).

 

Installed the Crucial (shorty) DP a few weeks ago, and have had a CEL ever since. AP is on its way...

 

Full catless DP will certainly cause a CEL, as you would expect. Besides which, it's the car is polluting more, so there's the karma issue there, too. I would recommend a full with a highflow cat, or a catless shorty at the minimum.

 

Though, now that I see the CEL, I wonder if the catless shorty is just as bad (karma-wise) as the full catless...

[SlegacyGT]

Just get the AP and it will take care of everything.

[TSiWRX]

The UP resistor, like you undoubtedly read, will take care of that EGT CEL, so no worries.

 

Whether or not you will receive a rear-O2 related CEL is, unfortunately, *vehicle specific* (i.e. "your" LGT versus "my" LGT or "anyone-else's" LGT) and also rather unpredictably "mod-specific" (i.e. related to the interation between your specific and unique LGT and the specific hardware that you install).

 

Whether or not you will be able to completely address both of the rear-O2 related CELs with, say, the "hard fix" (singular or stacked, long or standard-length, bored-out spark plug "antifouler/de-fouler") is also unfortunately rather variable.

 

I'm not trying to make your life difficult by giving you such uncertain answers - it's just that if you will do a search, you will see that I'm telling you the truth...too much variability.

 

A MIL-eliminator or other such device can be used for the rear-O2, but they are typically not recommended for use in-conjunction with aftermarket EMs (and some may report "not-ready" states on OBD-II cycles), so when you install your AccessPORT or ECUTek, be sure to remove it and have your tuner take care of these two pesky rear-O2 related CELs for you via software.

 

Meanwhile, all you can do is to get the parts to do the hard fix - until you have enough saved up to address the problem via EM.

 

 

As for the pros/cons of a shorty versus a full-length?

 

The "shorty" way of doing things does offer you an undeniable advantage in terms of modularity. You can retain the stock third/last cat, if catless-odor and/or inspections worry you; you can run a "race-pipe/test-pipe" when you hit the track/strip to gain best throughput; you can replace each component separately should one or the other be damaged or if upgrades are deemed necessary, for whatever reason. However, at the same time, in many cases, you may see "better" results, especially with "off the shelf" maps, by using specific full-length high-flow catted or uncatted pipes with specific EM-programs (i.e. using the Cobb catless full-length DP with their off-the-shelf "Stage II" map, pairing these components further with a full cat-back).

 

To me, IMveryHO, this choice is one to be made on a "personal preference" level - for despite various claims, most here have seen power gains that are so close to each other as to make the differences a nil-consideration (matching catted vs. uncatted vs. HFC catted, of course!), and various manufacturer claims to the contrary, as well.

[G.T.Subie]

Thanks for all the info, helpfull stuff. I guess I will be waiting to do the DP with an AP.

[TSiWRX]

 

Don't get too scared by what I wrote - with my particular LGT using my particular combination of mods (at the time, it consisted of the Perrin Short Ram intake paired with the duo of Crucial UP and shorty DP), I actually went quite a number of miles, for about a two week duration of everyday driving, along with a few longer highway trips, without any CELs elicited.

 

It's completely viable and acceptable to do the "hardware mods" before you do the software - it's just that most either do it the other way (i.e. go "Stage I," using the AccessPORT alone, first) or do the two simultaneously. Typical gains seen from "Stage II" *hardware only* modifications are similar to off-the-shelf Cobb "Stage I" map gains - only with its power delivery curve not quite as smooth, but at the same time, with the UP change, most also report a slight decrease in spool-delay.

 

I simply mentioned the variability of the rear-O2 related CEL issue to make you aware of them - not to scare you away. If you prepared for the eventuality/possibility, then when and if you do incur one and/or the other CEL, you'll simply be ready to make the necessary changes, and get right back on the road.

 

That's what happened when I finally got my p0420 CEL. I got the code pulled (free at AutoZone, this was before I'd invested in an OBD-II code-reader), and just said "oh, I know exactly what to do with that!" - went home, plugged in the mod, and never even broke a sweat.