What kind of hp gain can I expect from these? Do I need to have my engine retuned?

 

You might seriously consider the plenum spacer too. Most bang for the buck.

So a total hp gain of 20-25hp at the wheels is not unrealistic if you do the tune (with the spacer).
With exhaust upgrades air/fuel ratio becomes more critical. You should do it.

 

I'd say more like 1/2 that WITH the spacer. maybe 20-25 at the wheels with every bolt on available and a good tune on top.

 

get a MD 5/16 Spacer and pullys to help... maybe like 25 rwhp

you will need to reset your ECU

 

I meant everything he had PLUS the spacer. Not just the spacer + tune.
But the exhaust is real reason he needs a tune, not just a reset.

 

Sweet! Got some dyno sheets I can see that shows this?!?!

 

Still not enough

 

go to some dyno days... there has been a bunch around here over the years... Yes it does add that much power... no I will not waste time searching the dynos for you. Enough people including myself have seen it first hand - and the dynos are out here and on my350Z that show your all important "proof".

 

If anyone has these dynos handy then I would appreciate them being posted up. From the info I have seen here and my350z, it shows getting 20-25 rwhp through the range pretty tough to come by with simple bolt ons and a decent tune.

 

I agree. And with no headers and high flow cats

 

you know... come to think of it - none of the mods I have (or any of the dozens of people I've been around for three years have) really do anything... Intake, exhaust, and plenum spacer combo doesn’t do a damn thing.

I don’t know why I've been kidding myself all this time... I'll be sure to tell the dozens of others I know that they are kidding themselves too... And the posts that do exist - including ones from structured independent testing that have been published (albeit longer ago than most have owned their cars) - are obviously all marketing hype - even though the independent entities and dozens of by-standers witnessing it have all at one time or another posted results.

Oh, I shouldn't forget that the annual Stillen day dyno results and the multitudes of Church Automotive Dyno days (some specifically designed for product testing like Motordyne, U-Tech/Osiris, among others) are all skewed... By the way, TechnoSquare and all the research the has proven before and after gains is a myth... Must be the So Cal sun…

Yep. I've been wrong about all the 1/4-mile wins I've had in my car and the dyno pulls that have shown gains... Silly me. How could I not have realized it's all an illusion.

I now defer to less than a handful of knowledgeable experts that know more than the hundreds of us foolish ones.

Sorry for being so blind in my attempt to ascertain reality. I now know that bolt-ons can’t possibly amount to 25hp... Gee and to think it only took 3 years and hours and hours and hours of research and communication with other industry professionals (who obviously are oblivious as well) to realize we're all wrong about the facts that present themselves.

Oh well, live and learn.

 

All i am asking for is facts. Everytime I ask, nothing is ever produced. Just a bunch of talk. I dont want to see stillen's dyno. They are selling the products, I expect them to do whatever they can for their products to appear in the best light. I would be happy to concede that bolts on add XX amount of power if I can see a baseline independent dyno and the afterwards one with the same correction factor. Everyone likes showing SAE numbers for their baseline then STD for the afterwards so they can feel better about what they spent to get there.
I really do not think I am asking for much here. When I felt a gain with headers and a tune on my past VQ, I went and had an after dyno at the same place as the baseline. I gained 12whp throughout the band and peak around 20. That makes a believer out of me. If I can just see the same on this car then I would gladly concede. All I end up getting is a bunch of excuses why the dynos are not around anymore. Then I am told to look on my350z for the info where I see and talk to people with first hand knowledge that say it is not possible for a few bolts on either an MT or AT to get 25rwhp throughout the band even with a tune unless the car was in horrible running condition beforehand.

 

^^why don't u try it out urself and post ur results then? This is a forum not a personal answering service for ur questions. The info is there, don't get pissed at us for not doing the research and legwork for u.

 

I know, your right... it just doesn’t exist. It's foolish to think it does. But I've seen the light now - I realize it's a pipe dream to think any gains are to be had.

I knew this forum would be good for something to me one day... I'm so glad threads like this are here - otherwise I would have continued to wrongfully believe all those silly things I've been imagining all this time.

BTW, when I mentioned “Stillen Day” dyno results I was not talking about Stillen dynoing their own product for marketing It’s an event that hundreds of Gs and Zs go to annually – and many dyno their vehicle… and guess what, they don’t all have Stillen products on them.

Not that it matters because they all are just kidding themselves like me… in fact I’m gonna go shred the dynos I have from 2 of those events… I guess I should shred my dynos from Church Automotive too… Oh and the one from the Dyno Shop in San Diego (man those were all good numbers, good thing I know now that they are bogus)… I need to make some calls first to let a few researchers I know (that have stacks of various dyno charts from boatloads of VQs) and let them know they are delusional and they should burn all the data.

Thanks again to great threads like this that finally got me to open my eyes and realize my car is the same HP & TRQ as stock (maybe a few hp difference here and there depending on atmospheric conditions, but of course not from any bolt-on mods – what a silly thought it would be to think the bolt-ons did anything). I am so relieved that I have been enlightened.

 

common jonnylaw - come to the light... stop trying to justify all those great mods you have - oops, I mean all that money you wasted on those worthless mods.

Hey, by the way did you get together with the FX at the event out there?