Car: 06 R53, intake, catback, 380cc injectors, 15% S/C pulley, RMW tune

New: Alta header (4 -> 1, 3" longer primaries than stock) with stock cat transferred on (no pre-cat).

Question: should I get retuned? The car previously pulled 201 whp, 191 trq. I know tweaking the tune would result in more powuh, but at the moment I'm just interested in reassurance that the thing won't be running lean on me.

I thought I tried before — we can't measure air-fuel ratios with a Scanguage, can we? Any other gauge options that might illuminate whether it's running tip-top?

Nothing like having the car off the road for two weeks and doing both power and handling mods to throw your sense of balance off. Subjectively feels like it's breathing a little clearer, and sure sounds nice besides the heat shield rattle.

edit: no codes yet from the change. Might that ultimately determine whether a retune is needed?

 

Shouldn't need to, but you are getting to the point of max duty on the injectors with the mods you currently have. So a tune and new injectors should be on your short list of mods to do.

 

a tune would maximize the gains but not a must have.

 

Don't think the header is worth another tune with those mods; it's not going to be a huge gain until you slap a BVH on the other side of it...


Those are already pretty big numbers for those mods.

 

I haven't gotten a tune ever since adding the header w/ stock cat welded in place. Been running with it for about a year. Previously tuned with the other power mods.

 

Scangauge is crap for monitoring a/f ratios.

You need a wideband to do that job.

Scangauge refresh rate is simply way too slow.

 

Alta makes a header?

 

Apparently. I bought it used with whatever use to be below the expansion pipe hacked off, and it has a little cutsey alta insignia on one of the primaries. I brought it and the stocker to a shop without the car, they had to jig it to get the fit and flange correct, but it fits perfectly and still worked out to be relatively economical. Wouldn't have worried, but I bought a WRX last fall and it seems those cars are very fickle with even simple intake mods.

Thanks for the reassurance. I'd say I can wait and dream about larger injectors, cam and head with a retune some day.*nervous schoolgirl giggling* yes, car pulls much healthier to redline, doesn't feel like it's running out of steam. I'm content again for the moment.

 

it may be old school, but there's a very good thread around here on reading the plugs...

Not disagreeing with any of the helpful posts here at all, but one can never be too cautious when a potential lean condition could occur...

Cheers,

Charlie

 

I'd look at getting a tune. It was the most recent 'mod' that i've done, and I was surprised at the effects. Next on my list is a cam, full port/polish and injectors, and i'll definitely be getting another tune at that point....
just my .02...

 

Thank you Charlie, that is very good advice that I will take you up on. The car still has the plugs that came out of the factory, was thinking of preventatively changing them this season, would be the best and easiest opportunity to judge what it's doing (catch anything really bad). Old school is good