Stillen Headers installed - Review/Pics/Vid/Dyno

SoCal 370Z · 04-19-2009, 08:13 PM

Great write-up, but I am waiting for my free demo ride

to handout your rep point. Anyway, what's next...engine tune?

m4a1mustang · 04-19-2009, 09:40 PM

From the video that almost sounds *too* loud, but I'll take your word that it's quiet while driving like a granny.

RCZ · 04-19-2009, 09:56 PM

Umm, quick question...why did it take 3 hours to wrap the headers...thats like a 20 minute job...

semtex · 04-20-2009, 07:41 AM

Quote:

Originally Posted by RCZ

Umm, quick question...why did it take 3 hours to wrap the headers...thats like a 20 minute job...

*shrug* I didn't do it; my mechanic did. I will say this though -- my mechanic is very meticulous. If something doesn't look perfect to him, he will undo everything and start over until it looks perfect. But to be honest, I will also say that time management isn't his strongest point. My guess is that the 3 hours included an undisclosed amount of 'distraction time'.

Quote:

Originally Posted by m4a1mustang

From the video that almost sounds *too* loud, but I'll take your word that it's quiet while driving like a granny.

Would you guys like me to make a vid clip just driving around normal with my stereo playing? Would that help? You know, at one point in the clip as I'm about to turn onto a main road, my radar detector starts going off. I didn't change the volume setting of my V1 from prior to the header installation. So if you go back and play that bit, that might give you a better idea. It even continues beeping 1 or 2 times after I make the turn and go WOT again. Another thing you can listen for is my turn signal clicker. You can still hear it clearly even when the engine is under load. Now, our clicker isn't a loud one, so I think you can make an inference from that as well.

Quote:

Originally Posted by SoCal 370Z

Great write-up, but I am waiting for my free demo ride

to handout your rep point. Anyway, what's next...engine tune?

Underdrive pulley. Then a tune when UpRev releases their 370Z package.

m4a1mustang · 04-19-2009, 09:57 PM

I suspect beer was involved, but that's just me.

SOLISIMO · 04-20-2009, 06:49 AM

Quote:

Originally Posted by m4a1mustang

I suspect beer was involved, but that's just me.

sounds like one of my jobs

t-ray · 04-20-2009, 10:08 AM

semtex, you don't know me from Adam, but I've been following your posts.

I've got an 05 g35 sedan 6mt, with pretty much full n/a boltons. Other than the fact that my exhaust is raspy as hell(full test pipes instead of hfc's), your car sounds almost exactly the same as mine. Very familiar.

And to be honest, that disappoints me. I don't want to go too far off topic, but I've always wanted a v8 sound, and that nissan v6 will just never sound the way I want it to.

Regardless, I've gotta go off topic again, in another direction: I'm eager to see your dyno results. With full mods and a utec tuned by sharif, my car has gone 13.26@104mph on drag radials in the 1/4. Before your headers, and no tune, I believe you put down 306hp on sharif's dyno. That's sick. That's 60hp *more* to the ground than my car, on the same dyno. Props man.

semtex · 04-20-2009, 11:05 AM

^Thx dude. I will have updated dyno results by Wednesday afternoon/evening, including numbers from Sharif's dyno.

semtex · 04-22-2009, 03:33 PM

Okay, the dyno results are in, and they are um . . . somewhat confusing. I went and did dyno runs on both DynoJet and DynoDynamics just like I did last time.

Let's start with DynoJet.

This is the run I did last time, before I had the headers installed:

This is the run I did this morning, after installing the headers:

Kinda underwhelming, right? A max hp gain of 3.31, and a torque gain of 2.1 ft-lbs. I mean, at this point I was thinking "what a freakin waste of money!"

So then I make the drive over to Forged Performance to do a run on their DynoDynamics.

This is the previous run, prior to the headers:

Now here's this morning's results. This first graph shows HP and A/F:

This one shows torque:

So . . . what to make of this?

On DynoDynamics, I get a gain of +10.8 hp, which certainly makes me feel better. But I get a small loss in torque instead of the small gain I got on DynoJet! I go from approx. 251 to 247 ft-lbs. And that's comparing peak to peak. The delta in the lower to mid rpm range is actually larger than just 4 ft-lbs (unfortunately Sharif partially obscured the lines with his logo).

I'm going to go out on a limb here and say that I don't really trust the DynoJet results. I say this because the shop with the DynoJet is really close to me, and I went and did the DJ run before the DD run, so I'm thinking that my engine wasn't adequately warmed up. Last time, I drove the 45 miles to Forged and did the DD run first, before driving back and hitting the DJ.

Well, the charts are there for you all to look at and draw your own conclusions. My own conclusion from these results is that if you've already done the intakes and HFCs and cat-back, the hp gain you'll get from the headers is either negligible, or at best modest (relative to what you'll get from the other components), and you'll either lose a little torque, or at best gain a negligible amount. Are the headers worth it once you factor in installation cost? I can't answer that for you -- it's an individual decision.

All in all, I have mixed feelings on this (based on the DD results). I like the HP gain. I like 317.2 a lot better than 306.4. But I'm not pleased about the loss of lower mid-range torque.

wstar · 04-22-2009, 03:53 PM

Quote:

Originally Posted by semtex

All in all, I have mixed feelings on this (based on the DD results). I like the HP gain. I like 317.2 a lot better than 306.4. But I'm not pleased about the loss of lower mid-range torque.

Are you sure that the low-rpm torque loss wasn't just from ramping the throttle in? On my DD run, I don't really trust any of the numbers under 3750 rpm or so as I'm pretty sure the engine wasn't solidly WOT until shortly before 4K. Even then, the way my torque doesn't really peak up until about 4250 is suspicious (this may have been lag between hitting WOT on the pedal and the engine really starting to breathe like WOT).

Given the data we have so far (including yours), I think it's fair to say that the headers aren't great bang per buck (and especially aren't good bang per installation hour), but I have a hard time believing we really lost torque on them given the graphs and the unknowns.

There's also the ECU consideration. The headers may provide better gains under good tuning (or not), we'll have to see.

semtex · 04-22-2009, 03:59 PM

Quote:

Originally Posted by wstar

Are you sure that the low-rpm torque loss wasn't just from ramping the throttle in? On my DD run, I don't really trust any of the numbers under 3750 rpm or so as I'm pretty sure the engine wasn't solidly WOT until shortly before 4K. Even then, the way my torque doesn't really peak up until about 4250 is suspicious (this may have been lag between hitting WOT on the pedal and the engine really starting to breathe like WOT).

Given the data we have so far (including yours), I think it's fair to say that the headers aren't great bang per buck (and especially aren't good bang per installation hour), but I have a hard time believing we really lost torque on them given the graphs and the unknowns.

There's also the ECU consideration. The headers may provide better gains under good tuning (or not), we'll have to see.

Even if it was from ramping the throttle in, why would it show a loss? The throttle had to be ramped in the last time as well, right? I don't know. I'll tell you guys my driving impression so far though. I can notice the loss of torque on the low end. I mean, before the dyno, I kinda suspected it, but now I have confirmation. But paradoxically, it feels quicker once I really get into it, which I guess is where the hp gain comes into play. Sound wise, I'm still undecided as to whether I liked the way my car sounded before the headers vs. after. To be 100% honest, I do not feel that this was money well spent. I'm actually toying with the idea of having my stock headers put back in. But then that's another $750 out of my pocket, right? So I probably won't. Plus you're right about the tune. It'd be premature to rip these out until I see what a tune will do.

wstar · 04-22-2009, 04:14 PM

Quote:

Originally Posted by semtex

Even if it was from ramping the throttle in, why would it show a loss? The throttle had to be ramped in the last time as well, right? I don't know.

Well, the throttle inputs might not be the same between the runs. I think on my next DD run, I'm going to ask the guy to make sure he drops back under 3K before he floor the throttle and takes the run. It's not a very well-controlled variable, and since most people are just looking for the peak HP number anyways, it doesn't matter to many. It would be nice to hook up OBD-II to the dyno machine and get throttle position mapped onto the graph as well if that were possible.

Quote:

I'll tell you guys my driving impression so far though. I can notice the loss of torque on the low end. I mean, before the dyno, I kinda suspected it, but now I have confirmation. But paradoxically, it feels quicker once I really get into it, which I guess is where the hp gain comes into play.

That's what I've noticed as well, mostly in the form of the car having less "jerk" at low rpms (esp at 3k-ish and below). Looking at my graph here:

The low torque before hitting the peak at 4250 can either be low-rpm torque loss from headers, or it again could be throttle input issues near the start of the run, I'm not really sure. I'm pretty sure everything before 3500 is from lack of WOT though.

Quote:

Sound wise, I'm still undecided as to whether I liked the way my car sounded before the headers vs. after. To be 100% honest, I do not feel that this was money well spent. I'm actually toying with the idea of having my stock headers put back in. But then that's another $750 out of my pocket, right? So I probably won't. Plus you're right about the tune. It'd be premature to rip these out until I see what a tune will do.

I actually like the sound of my full setup most of the time. The only thing that still bugs me (and that the headers undoubtedly exacerbate) is the extreme rasp around the 2500-3000 range even at light throttle. I wish I knew how to fix that with some kind of rubber damper (like the two that are already on there from the stock setup).

semtex · 04-22-2009, 04:18 PM

Quote:

Originally Posted by wstar

I actually like the sound of my full setup most of the time. The only thing that still bugs me (and that the headers undoubtedly exacerbate) is the extreme rasp around the 2500-3000 range even at light throttle. I wish I knew how to fix that with some kind of rubber damper (like the two that are already on there from the stock setup).

Hmm...I don't detect any rasp. I wonder if the fact that I had my headers wrapped is making the difference.

user123 · 11-20-2009, 07:01 PM

Quote:

Originally Posted by semtex

Okay, the dyno results are in, and they are um . . . somewhat confusing. I went and did dyno runs on both DynoJet and DynoDynamics just like I did last time.

Let's start with DynoJet.

This is the run I did last time, before I had the headers installed:

This is the run I did this morning, after installing the headers:

Kinda underwhelming, right? A max hp gain of 3.31, and a torque gain of 2.1 ft-lbs. I mean, at this point I was thinking "what a freakin waste of money!"

So then I make the drive over to Forged Performance to do a run on their DynoDynamics.

This is the previous run, prior to the headers:

Now here's this morning's results. This first graph shows HP and A/F:

This one shows torque:

So . . . what to make of this?

On DynoDynamics, I get a gain of +10.8 hp, which certainly makes me feel better. But I get a small loss in torque instead of the small gain I got on DynoJet! I go from approx. 251 to 247 ft-lbs. And that's comparing peak to peak. The delta in the lower to mid rpm range is actually larger than just 4 ft-lbs (unfortunately Sharif partially obscured the lines with his logo).

I'm going to go out on a limb here and say that I don't really trust the DynoJet results. I say this because the shop with the DynoJet is really close to me, and I went and did the DJ run before the DD run, so I'm thinking that my engine wasn't adequately warmed up. Last time, I drove the 45 miles to Forged and did the DD run first, before driving back and hitting the DJ.

Well, the charts are there for you all to look at and draw your own conclusions. My own conclusion from these results is that if you've already done the intakes and HFCs and cat-back, the hp gain you'll get from the headers is either negligible, or at best modest (relative to what you'll get from the other components), and you'll either lose a little torque, or at best gain a negligible amount. Are the headers worth it once you factor in installation cost? I can't answer that for you -- it's an individual decision.

All in all, I have mixed feelings on this (based on the DD results). I like the HP gain. I like 317.2 a lot better than 306.4. But I'm not pleased about the loss of lower mid-range torque.

This is McFly from GenCoupe.com Forums - Your Hyundai Genesis Coupe Community

Someone over on our board posted a link to this thread. I'd like to help out. If you don't find this beneficial then feel free to ignore it.

I've analyzed your Dyno graphs. I hope you find this information helpful.

Enjoy:
Why did the 370Z gain 3whp on the Dynojet and 11whp on the Dyno Dynamics?

Answer is that the Dyno Dynamics dyno wasn't done the same before and after. The 370Z continues to make more power the higher the RPM you take it. So, if you short change the car and don't run it to it's highest RPM possible, then you don't get a good reading. They have to run the car to the same RPM on the before dyno, and the same RPM on the after dyno. On the first Dyno Dynamics dyno run they ran the car to only 7100RPM, then on the second dyno run they ran it to 7600 RPM. So, since they ran the car to a much higher RPM the second time, it's only obvious that they were going to get a higher reading, and that they short changed the car on the first dyno run.

If you look at the power that was made at 7000 RPM on both [before and after] dyno run's to make it fair, you'd see that they made 305whp on both the before dyno plot and on the after dyno plot. They made no power, and actually lost power at anything below 7000RPM, in fact. That's how you should be reading the dyno plots, at the same RPM on both the before dyno plot and after dyno plot. Another way to read the a hp graph is to get better resolution of the hp plot... and this is to actually be reading the torque plots. Yes, understand a hp plot and where the gains are by reading the torque graph... and what you see is that there was a loss everywhere, except that the difference disappears at high rpms, and there is no gain/loss.

Put plainly, either learn how to read a dyno plot OR even more simply, you can throw out the Dyno Dynamics readings because the operator screwed up. RUN IT, and RUN IT HIGH!... or at least run it the same.

Hp gain on stillen headers on a 370Z, is about 10hp loss to 3hp gain, depending on where in the RPMs you are... and the gain of 3hp is only for a split second at 7000RPM. WASTE OF MONEY!

People think they know, but they have no idea.

Like I said, If you don't find this beneficial then feel free to ignore it. At the least, I hope I don't get flamed for trying to help out.

semtex · 11-21-2009, 05:52 AM

Quote:

Originally Posted by user123

This is McFly from GenCoupe.com Forums - Your Hyundai Genesis Coupe Community

Someone over on our board posted a link to this thread. I'd like to help out. If you don't find this beneficial then feel free to ignore it.

I've analyzed your Dyno graphs. I hope you find this information helpful.

Enjoy:
Why did the 370Z gain 3whp on the Dynojet and 11whp on the Dyno Dynamics?

Answer is that the Dyno Dynamics dyno wasn't done the same before and after. The 370Z continues to make more power the higher the RPM you take it. So, if you short change the car and don't run it to it's highest RPM possible, then you don't get a good reading. They have to run the car to the same RPM on the before dyno, and the same RPM on the after dyno. On the first Dyno Dynamics dyno run they ran the car to only 7100RPM, then on the second dyno run they ran it to 7600 RPM. So, since they ran the car to a much higher RPM the second time, it's only obvious that they were going to get a higher reading, and that they short changed the car on the first dyno run.

If you look at the power that was made at 7000 RPM on both [before and after] dyno run's to make it fair, you'd see that they made 305whp on both the before dyno plot and on the after dyno plot. They made no power, and actually lost power at anything below 7000RPM, in fact. That's how you should be reading the dyno plots, at the same RPM on both the before dyno plot and after dyno plot. Another way to read the a hp graph is to get better resolution of the hp plot... and this is to actually be reading the torque plots. Yes, understand a hp plot and where the gains are by reading the torque graph... and what you see is that there was a loss everywhere, except that the difference disappears at high rpms, and there is no gain/loss.

Put plainly, either learn how to read a dyno plot OR even more simply, you can throw out the Dyno Dynamics readings because the operator screwed up. RUN IT, and RUN IT HIGH!... or at least run it the same.

Hp gain on stillen headers on a 370Z, is about 10hp loss to 3hp gain, depending on where in the RPMs you are... and the gain of 3hp is only for a split second at 7000RPM. WASTE OF MONEY!

People think they know, but they have no idea.

Like I said, If you don't find this beneficial then feel free to ignore it. At the least, I hope I don't get flamed for trying to help out.

You're not going to get flamed for trying to help out, but you could lose the condescending attitude. And I already stated that these headers are a waste of money, more than once.

04-19-2009, 08:13 PM	#1 (permalink)
SoCal 370Z A True Z Fanatic Join Date: Feb 2009 Location: US of A Posts: 2,842 Drives: Answers Rep Power: 34	Great write-up, but I am waiting for my free demo ride to handout your rep point. Anyway, what's next...engine tune? __________________ ( Click to show/hide ) Why I NEVER say NO to the Panda Lou Fusz!!!

04-19-2009, 09:40 PM	#2 (permalink)
m4a1mustang A True Z Fanatic Join Date: Feb 2009 Location: Northern VA Posts: 55,385 Drives: on two wheels Rep Power: 6963	From the video that almost sounds too loud, but I'll take your word that it's quiet while driving like a granny. __________________ - Steve Zs & Coffee - Saturdays at 10AM in Fairfax, VA and Columbia, MD (Click the banner!) LIKE us on Facebook!

04-19-2009, 09:57 PM	#5 (permalink)
m4a1mustang A True Z Fanatic Join Date: Feb 2009 Location: Northern VA Posts: 55,385 Drives: on two wheels Rep Power: 6963	I suspect beer was involved, but that's just me. __________________ - Steve Zs & Coffee - Saturdays at 10AM in Fairfax, VA and Columbia, MD (Click the banner!) LIKE us on Facebook!

04-20-2009, 11:05 AM	#8 (permalink)
semtex A True Z Fanatic Join Date: Jan 2009 Location: Behind enemy lines Age: 54 Posts: 5,995 Drives: People to drink Rep Power: 33	^Thx dude. I will have updated dyno results by Wednesday afternoon/evening, including numbers from Sharif's dyno. __________________ "There are no small accidents on this circuit." -- Ayrton Senna 316.8whp & 248 ft/lbs (Dyno Dynamics) \| 319whp & 256 ft/lbs (DynoJet) (04/23/10) Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

04-22-2009, 03:33 PM	#9 (permalink)
semtex A True Z Fanatic Join Date: Jan 2009 Location: Behind enemy lines Age: 54 Posts: 5,995 Drives: People to drink Rep Power: 33	Dyno results Okay, the dyno results are in, and they are um . . . somewhat confusing. I went and did dyno runs on both DynoJet and DynoDynamics just like I did last time. Let's start with DynoJet. This is the run I did last time, before I had the headers installed: This is the run I did this morning, after installing the headers: Kinda underwhelming, right? A max hp gain of 3.31, and a torque gain of 2.1 ft-lbs. I mean, at this point I was thinking "what a freakin waste of money!" So then I make the drive over to Forged Performance to do a run on their DynoDynamics. This is the previous run, prior to the headers: Now here's this morning's results. This first graph shows HP and A/F: This one shows torque: So . . . what to make of this? On DynoDynamics, I get a gain of +10.8 hp, which certainly makes me feel better. But I get a small loss in torque instead of the small gain I got on DynoJet! I go from approx. 251 to 247 ft-lbs. And that's comparing peak to peak. The delta in the lower to mid rpm range is actually larger than just 4 ft-lbs (unfortunately Sharif partially obscured the lines with his logo). I'm going to go out on a limb here and say that I don't really trust the DynoJet results. I say this because the shop with the DynoJet is really close to me, and I went and did the DJ run before the DD run, so I'm thinking that my engine wasn't adequately warmed up. Last time, I drove the 45 miles to Forged and did the DD run first, before driving back and hitting the DJ. Well, the charts are there for you all to look at and draw your own conclusions. My own conclusion from these results is that if you've already done the intakes and HFCs and cat-back, the hp gain you'll get from the headers is either negligible, or at best modest (relative to what you'll get from the other components), and you'll either lose a little torque, or at best gain a negligible amount. Are the headers worth it once you factor in installation cost? I can't answer that for you -- it's an individual decision. All in all, I have mixed feelings on this (based on the DD results). I like the HP gain. I like 317.2 a lot better than 306.4. But I'm not pleased about the loss of lower mid-range torque. __________________ "There are no small accidents on this circuit." -- Ayrton Senna 316.8whp & 248 ft/lbs (Dyno Dynamics) \| 319whp & 256 ft/lbs (DynoJet) (04/23/10) Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf. Last edited by semtex; 04-22-2009 at 04:12 PM.

04-19-2009, 09:56 PM	#3 (permalink)
RCZ A True Z Fanatic Join Date: Nov 2008 Location: Miami Posts: 6,403 Drives: '09 370Z Rep Power: 1119	Umm, quick question...why did it take 3 hours to wrap the headers...thats like a 20 minute job...

04-20-2009, 10:08 AM	#7 (permalink)
t-ray Base Member Join Date: Apr 2009 Location: bham al Posts: 91 Drives: 05 g sedan 6mt Rep Power: 17	semtex, you don't know me from Adam, but I've been following your posts. I've got an 05 g35 sedan 6mt, with pretty much full n/a boltons. Other than the fact that my exhaust is raspy as hell(full test pipes instead of hfc's), your car sounds almost exactly the same as mine. Very familiar. And to be honest, that disappoints me. I don't want to go too far off topic, but I've always wanted a v8 sound, and that nissan v6 will just never sound the way I want it to. Regardless, I've gotta go off topic again, in another direction: I'm eager to see your dyno results. With full mods and a utec tuned by sharif, my car has gone 13.26@104mph on drag radials in the 1/4. Before your headers, and no tune, I believe you put down 306hp on sharif's dyno. That's sick. That's 60hp more to the ground than my car, on the same dyno. Props man.

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