Can i run this exhaust, being that it is a headerback with no cat or resonator, WITHOUT tuning?

will it be safe? will the car adjust?

ive heard rumors of crazy a/f ratios on the J's racing 70RR without tuning of like 15:1

truth?

thanks

matty

 

any other mods?

 

You will be fine. Many people run full 70mm or 75mm exhausts with full bolt ons and dont have any problems. It does make the car run leaner, but I doubt its to the point where you should be concerned.

 

I don't think its necessarily a problem, but you get to maximize your gains with a tune though.

 

i was told before that taking a bone stock s2k and slapping a J's Racing 70RR on it without a retune will result in A/F ratios or like 15:1

is this false? maybe the ecu takes time to adjust?

i plan to pick up a 70rr or 70rt and didnt want to tune the car right away...

the 70rr and 70rt are catless and have no resonator headerbacks

 

I'd personally never run a car at WOT with that kind of A/F ratio. From what I've read though, you should be fine.

 

I think it would help if you knew where in the RPM band the 15:1 A/F ration is, since you don't stay in a certain RPM range in WOT all the time.

 

I believe the data you are looking for started from the lips of Giles. He had some cars come in the shop for a tune with his EMU and on the preliminary pulls the A/F were scary lean. These were cars with intake, test pipe, and cat-backs.

It's more of a problem with the later AP2s than AP1s though.

Dev, the Laguna AP2 (06 IIRC) from New Jersey had scary high A/F when he made it to Giles, though I don't recall the exact number. See this: http://holyrollerdyno.com/Holyroller_Dyno/...Dave_Surti.html

-Mike

 

Shouldn't have as much of a worry with an AP1 like was previously mentioned. They run richer than AP2's, especially the '00-'01 models. But I would still get a tune whenever you can. Mainly for gains reasons, but better safe than sorry.

 

[QUOTE=daktruckie99,Nov 4 2010, 01:03 PM] I believe the data you are looking for started from the lips of Giles.