I've searched for days and I can't find what an answer.

I currently have the Vortech tuner kit with 3.12 pulley non revup with the Utec. I have headers, fast intentions test pipes and FI exhaust. I put down 351whp on a dynodynamics.

I am looking at replacing the Utec with the Osiris Uprev, and will need a new tune, so I was also thinking about adding a Plenum or plenum spacer at the same time.

My question is what is the best option for my combo, the spacer or something like the Kinetix SSV? And what kind of gains could I expect with the new Osiris tune and the spacer or Kintetix? Also is there anything else that I may want to add before my new tune? I'm thinking maybe meth injection...

 

Why would you downgrade to an osiris? You should be at around 375-380 whp BUT, your problem is that you are running headers and test pipes. Switch to stock headers and cats, and you'll make more power with the vortech.

The plenum mods do pretty much the same unless you have a a fully built motor w/ cams and are making massive boost. Just go with a plenum spacer and call it a day. You won't make much more power than your are currently at though....

 

Definatlly get the MotorDyne 3/8" spacer since you're using Vortech, then get a re-tune. You'll be supprised at the increase....Good Luck!
Gary

 

My tuner is recommending going to the Osiris for drivability improvements and better hot starts. He also said that it would get rid of my SES light. I think he prefers to tune with the Osiris as well. I have seen that there is some debate on which is better, so I'm just exploring some options. I did have stock cats and made 332whp. I then put on test pipes (because cats burned up), and made 351whp on the Dynodynamics (prob 385-395 on a dynojet) which is about right. I figure that if I'm going to get a new tune, I may as well do something else at the same time.

I dunno, haven't decided what to do yet...

 

THe osiris is a downgrade and might even blow your motor up like the HR on my my350z.com bc it's basically an upgraded reflash of the stock ecu.

I would never recommend going back to stock headers and cats... Yes, u loose back pressure but u gain the extra hp/tq on the top end.

Meth kits will help u add more timing and may let u see +20hp or u can try E85.

 

Yeah, I'm leaning towards keeping the Utec and just upgrading to the 2.87 pulley with water/meth injection. Pretty sure that will scratch my itch. I just put on some 20" wheels and I can feel a loss, especially in the midrange. So I want to overcome that with more power. Who doesn't want more power

Why are tuners pushing the Osiris uprev? Do they just want a reason to cash in on retunes?

 

who's your tuner? I have the gates belt for the 2.87 pulley if u want.

 

There are a couple threads regarding UTEC vs. Osiris for FI applications, search around. It's by FAR a "downgrade".

 

no active knock control above 5000 rpms is a downgrade, esp for a SC app where HP/boost and thusly AIT's is related to rpm.

you want the most control at the upper rpms with a SC'r.

 

Thanks for the input guys. I went in and talked to my tuner, Dave at Function:Tuned, and I am convinced to stick with the Utec. My next mods will be to add meth and either a plenum spacer or something like the APS tallboy or Kinetix SSV.

Your thoughts on the APS or Kinetix?

I am currently running the 2.87 pulley, my invoice said it was the 3.12, but I looked at it and it is definitely the 2.87.

 

A reflash would work just as well with your utech. You can also raise your idle and a ton of other things as well.

I don't believe that you gained whp with test pipes. You would be the first ever, so I believe you did have defective cats. Also, the huge differences in dyno numbers is incorrect as well.

 

Go APS. There's no reason to spend more on the SSV unless you want the bling. Meth will definitely help. You should be around 425 whp once all is said and done.

Do you have dyno numbers to prove this? I removed my motordyne plenum spacer and opted with an SSV. I never really felt any gains from my spacer, even when I was NA.

 

I think you're right about the test pipes. My cats did burn up and clog the exhaust, and were probably bad from the beginning. Who knows, all I know is the before and after Dyno numbers.

The difference in dyno numbers is pretty accurate. Funtion:Tuned's dyno reads really low, most people say about 13% lower than the average Dynojet. If you doubt that, just ask in the National G Club section. Dave (the owner of F:T) gave me that 13% number himself based on his experience (which is considerable).

Any ideas about the Plenum/intake manifold mod?

 

Take my SSV thats for sale!

 

Lol, I'm trying to figure out if I have time to come get it tomorrow.

Why are you selling it BTW?