caymandive

iTrader: (2)

I'm heading back to MachV to get a final Dynojet run completed to see how the headers are doing compared to my baseline I did a few weeks ago. I'll also be getting the Air/Fuel checked and posting my results this afternoon.

Elite Autosport

Can't wait to see the results!

caymandive

iTrader: (2)

According to the Dynojet I picked up +39.5hp at 5900rpm and +34.57 ft/lbs at 6000rpm.

I did this testing over my lunch break and if I had more time to let the car cool down before I jumped on the dyno I am confident I would have seen +40hp and a few more ft/lbs. The results speak for themselves. The headers yield gains everywhere and the once questionable air/fuel seems to be in check.


Are these results perfect. No. In my opinion this kind of testing needs to be done on the same day if possible as I did with my previous testing on the Dynapack. Weather conditions drastically affect the numbers, but it's safe to say these headers are guaranteed to provide you with no less than 35hp probably averaging 40+ and on the rare occasion closer to 50hp.

SAE



UNCORRECTED

alpha6164

Those are good gains. But i am not sure why you think that the AFR is in "check." The AFR is north of 13:1 under load from 2500-5300rpm, it does not even drop below 12:1 until 6200rpm. Most reputable tuner would consider anything higher than 12:1 and certainly 12.5:1 lean.

caymandive

iTrader: (2)

Apparently you don't know what the typical AFR looks like on the IS-F. On a turbo application I'd say your remark would be correct, but on a High Compression V8 this is normal. Check out the link below and you'll see the car is in "check" and actually running slightly richer.
https://www.clublexus.com/forums/5508696-post1.html

caymandive

iTrader: (2)

Well today was one of those horrible type days. I realized I was a day over due on my yearly state safety inspection so, I drove the car to the dealership only to get a "rejection" sticker on on my windshield in place of my normal state inspection sticker.

They said I failed because I have no cats on the car. I was ok, how does that have anything to do with the yearly safety inspection. It seems like it would only matter for my emissions test every two years. The service adviser said that the state requires cats on the car to pass. Ok fair enough I go home and pull off the JoeZ exhaust and start putting the OEM exhaust back on the car. During the install I realized I needed two new gaskets so I returned to the dealership. Just to double check I asked the service guy if I put the OEM exhaust back on, would I pass? He said I would have to put all 4 cats back on to pass. I was like ok i'm going to another shop for my inspection where I'm certain I'll pass, especially now that I have the oem exhaust on. I can tell you that with the headers and OEM exhaust combo, the car is 100% as quiet as it was stock. Now that I have this combination I am planning to get a new Dyno to see how much power I've lost. If it's not much and I'm still able to crack 400whp on the dynapack I just may keep the car as is, though I really loved how wicked it sounded before. I plan to dyno this combination on Friday so I'll post the results then. Should be interesting.


Oh and get this. The service guy suggested I just gut the cats!! That way I would pass the visual. WTF!? I'm guess he doesn't realize how expensive those things are.

infinus

^ or if your really sneaky weld some fake cats on the outside of the joe z piping I wont have to go to an emissions test till 2013 and as long as it doesn't throw a light I'm fine

caymandive

iTrader: (2)

What I'd really like to have is a JoeZ PTS type exhaust with high flow cats that include v-bands so that I could swap in and out test pipes.

combfilter

iTrader: (3)

Why are you getting your inspection done at the dealer?

Go to those little gas station places that "we do state inspections" type. They don't look, they just hook up the odb tool and honk your horn. 10 minutes later you have a sticker on your windshield.

caymandive

iTrader: (2)

I went today to a (Non-dealership) place and I was out the door in 10 minutes with a new inspection sticker. Next year I'll be more prepared and NOT go to the dealership for the inspection. Lesson learned.

BB/F

Did the original place know the car has 4 cats? If so, don't go back there to get the reinspect now that you have the stock system back on. Va does check that emissions equipment is on the car. You can gut the cats and get away with the visual. I believe that when it's time for emissions, they will do a visual check and then connect the car to the obd2 port to check for any reported emissions equipmet codes. You should not have to do the dyno emissions check.

caymandive

iTrader: (2)

Whats funny is the car with full exhaust (no cats) passes emissions just fine. All they do is read the OBD2 port. Unfortunately I found out the hard way is that in VA they do the "visual" inspection as part of the yearly safety inspection. So as long as you go some place that does not know this car comes with 4 cats from the factory then having just 2 cats passes no problem.

carlosg

It would be interesting to see if there is any gains by eliminating the down pipe cats and substituting them with either high flow cats or test pipes vs. headers

Joe Z

iTrader: (10)

^^ Our F's already come with 4 Factory Installed High Flowing CAT's...

**
James, glad to hear you easily passed today... But yeah I agree with you on staying away from the dealership for stuff like this..
They stick to the state rules "by the book"

This next dyno you perform, will be very interesting for sure..!!

I guessing you will have the PTS Exhst back ON by next weekend
(or mid Aug)


Talk to you soon

Joe Z

infinus

They have a modular system like that for 350z and G35's. But if you just weld a fake shell on the outside of the exhaust so it just looks like it has a cat it shouldn't be an issue and you won't have to cut up the exhaust since the exhaust will run as is through the shell. You'll get the same sound, performance, not have to do any cutting and still pass the visual. After hearing how sexy the headers and exhaust sound I don't think I could live with the quiet sound.

One positive note though we'll finally be able to answer the "header only" question people have been asking. I also wonder how much if any it will affect the dip in the curve.