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Discussion Starter · #1 ·
As I mentioned in an earlier thread, for those of you who are contemplating headers but have not yet done a purchase/install - be patient a while longer! ;) There are a few developers who will have offerings over the next several weeks. I am trying to track all of them.

I had an in-depth chat with Ernie Francis at Breathless today re his very new header design. Ernie had just come back from one engagement and is now off to the SEMA show. He has sold out of his original small run of the new headers, and expects more to be available in late November. Here is some more specific info:

1. All sets to-date have been made and are planned to be made in jet hot coated mild steel. Stainless may be available, but at a significantly increased price. I told Ernie of my personal preference for stainless due to my own less than satisfactory prior experiences with exhaust components fabricated from mild steel. I also reminded him that there have been a significant number of complaints from some purchasers of a competing header which is mild steel. Ernie responded that he was well aware of these complaints, and his units were considerably thicker, thus stronger. IMHO only, I would still prefer stainless, but will keep an open mind on this subject until his units have been out in the real world for a few months...

2. His headers do not have a "d" port design to provide an exact exhaust port match to our heads. Ernie says that this is not necessary, and perhaps he is correct, I am not technically knowledgeable to know. But, as I ask myself, why not offer this, if I am designing a new set from scratch? Surely, enough Z's are out on the street to make it commercially viable - IMHO. Everything I have previously read about port matching is that it is a Good Thing.

3. Headers are designed for ease of install and for ease of clutch replacement if necessary by having collectors, flanges and fourth pipe on passenger side removable. I questioned Ernie closely on this point as removable also means an enhanced chance for leakage. Ernie told me that substantial testing has been done to ensure this is not an issue. For example, the collectors are attached with RTV red sealant as well as two bolts. Surely this feature would be a giant plus, if it works as advertised.

4. Headers are of a stepped design with primaries starting at 1 3/4 inches and "stepping up" to 1 7/8 inches, 8 inches from the flanges. From all that i can gather, this is a notable improvement on what has been available to-date.

5. Expected power gains. Ernie expects an approximate 15 rear wheel h/p gain and even more importantly a substantial rear wheel torque gain on a basically stock Z06 (intake mods only). No dyno results yet, but he has asked me to get back with him on this in the not too distant future after he has done before/after relative dyno power testing on his Mustang dyno.

So, stay tuned to this channel for a BPP update later in November - and remember, more new headers are coming soon! ;)

After thinking about this for some time, I believe my ideal header manufacturer would offer:

1. Stainless construction;

2. Design which maximizes power while minimizing install headaches;

3. Port matching to our cars;

4. Stepped design;

5. One basic application for essentially stock cars, one for substantially modded cars;

6. Complete before/after relative gain dyno results which are repeatable;

7. A "reasonable" price! :eek:

Honently, I don't think ANY of the headers under development will meet all of my personal criteria, so I guess it will take some further careful comparative analysis to make an informed decision. Kinda like a local retailer sez "an informed consumer is our best customer".

That's all fer now....:)
 

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EXCELLENT!!

Exellent report Investigator!! :cool: I've seen Ernies design and they are sweet, although I would prefer stainless also!!
 

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Head Exhaust mating with Headers

BAD JUJU...................
They must mate............if they are not as close to perfectly matched, then any exhaust port work, is for naught.........
I think your bud, needs to re-think this position........FLOW, in and OUT.........a MUST.
 

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Re: Head Exhaust mating with Headers

ZO6LS6 said:
BAD JUJU...................
They must mate............if they are not as close to perfectly matched, then any exhaust port work, is for naught.........
I think your bud, needs to re-think this position........FLOW, in and OUT.........a MUST.
I want someone to ante up - get some custom exhaust port matched headers made. Install some of the "lowly" un-port matched headers, dyno, same day, pull them off and install the port matched custom set - let's see how much it really matters....


exhaust porting for naught just because the headers aren't port matched?!? are you crazy!

Again, I go back to my original statement - if you want that little tiny amount of power back that port matching may provide - go clean the damn air filter...:p
 

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Are yo crazy??

No..........but lets be adults and be sensible here.......ok?
What in hades is the reason for matching INTAKE manifolds, and the ports?( not to mention micro smooth finishing).........FOR optimum air flow, with the LEAST amount of resistance possible........( Turbulence)
Does it NOT make sense )( likewise), that you want it to be EXTRACTED just as smoothly?????.............
FLOW, IN, FLOW OUT...........
While I agree, that the intake side is MORE important.........
The fact remains that you are attempting to scavenge the exhaust as effectively, as you are trying to intake it..........think of it as Elax for your car:D
 

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And I'm not disagreeing with you, not in the least. Of course it's more efficient to have the exhaust side matched. I just find it humorous that it's that big a deal to people - as though the LS6 was the only motor with this problem.

We are dealing with MASS PRODUCED headers. There isn't a perfect match between ANY header and the LS1 head, and there won't be one with an LS6 head. There isn't a perfect match between the INTAKE and the head either!! We're dealing with mass produced parts - not matched sets....I just trivialize the cost effectiveness of port matching a mass produced set of headers - I don't see it EVER happening - Customized set? Hell yeah! Mass produced? Nooooo....Call be crazy, but I've yet to see a header manufacturer's tolerances THAT tight before. Go out and dump many thousands on a customized set of Ti headers that are port matched to YOUR heads (not ALL LS6 heads). This port matching "issue" isn't going to be resolved by simply swapping flanges, as has been mentioned before it's also going to entail throwing the primaries onto a mandrel and giving the first few inches the "D shape". I just really honestly think we are dealing with a marginal amount of power here - and IMHO, time/worry is better left to other areas to gain that power back - OR - go for it, and dump a ton of cash on doing it RIGHT. :)
 

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Discussion Starter · #7 ·
Guys, if I might don my referees white shirt and bowtie for just a moment... I would like to see the d port matched headers (and initial part of primaries) done en mass, catering to the Z06 "extreme performance enthusiast market" Just think, between '01 and '03, there will be at least 20,000 Z06's out there. Even if 5% of of these "extremists" anteed up, that's 1000 sets - gotta be some profit there for mass production.

On the other hand, maybe all this port matching on the exhaust IS overrated. Why not wait until these units are done with their relative power gain testing on the dyno, and then we will have more definitive info? I think we will know a lot more about this issue by the end of this year...

Remember, there may be others in the wings....;)
 

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We are dealing with MASS PRODUCED headers.
As the prices go up, so do the expectations.

I want someone to ante up - get some custom exhaust port matched headers made. Install some of the "lowly" un-port matched headers, dyno, same day, pull them off and install the port matched custom set - let's see how much it really matters....
I think this is best investigated on a simulator.

The step from an unmatched flange changes the wave reflection characteristics of the primary tube. That change might help your stock cam engine at certain RPMs and hurt at other RPMs. The impact really depends on the combination. So the guy with a different cam may benefit, where the match-up didn't help the stock cam.

When I worked for the big-3, I spent hundreds of hours (of my own time) studying engine combinations on one of the best engine simulators ever coded.

There are simpler simulators available ($100-500) that do a pretty good job and are extremely useful tools. Ricardo WAVE is probably the most serious tool available for purchase, but it is very expensive (I haven't used it). Gordon P. Blair's "Design and Simulation of Four-stroke Engines" is a very nice, heavy text on the subject.

Once the model was built, you could compare the difference between an H-pipe with the crossover tube 5" behind the collector vs. 15" behind the collector. Or what if the crossover diameter is 2" instead of 3"? What if it is 3" long vs. 10" long?

Ater lots of simulation, I wanted an H-pipe with 3 crossovers. Each with a valve that opened or closed at a different RPM.

Race engines typically have a lot more valve overlap than the LS1/LS6. That overlap makes the engine very sensitive to exhaust tuning and different exhaust configurations. The cams I most often simulated had around 106 degrees of separation - not your typical LS6.

Whenever I would change the exhaust, I needed to adjust the cam to fully appreciate any benefit of the change (close the intake earlier, etc). On a dyno, you need a super budget for these things. On the sim, you just need time..

This work generally wasn't about peak numbers - it was area under the curve. You typically gave up a higher peak number (at least for road racing) in the interest of more under the curve.

I also looked at step headers. They do not always result in better performance. Like most exhaust stuff - it depends.

I'm not sure that anyone has really spent much time *testing* headers and exhaust for these various common LS1/LS6 configurations. I think the 346/385/420/etc are all going to want something different.

I have friends who will do runs on the good simulator for me. But there are a lot of LS6 engine measurements I don't have yet (intake port&runner dimensions, plenum volume, exhaust port dimensions, etc).

When I eventually get a good model built, it will be interesting to see how an expansion at the flange impacts performance.

Regardless, it looks like the exhaust is going to soon be much better covered. Now I can't help but wonder if there are any new intake choices on the horizon??
 

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The most important thing about the headers, or any header for that matter is that the flange nor any other portion of the header do not obstruct the port. The simple way to check this is to use your gasket as a template. For instance on my GN, the ATR headers were smaller than my exhaust ports. Since this is a turbo motor, getting the exhaust right is critical. But, the headers come with instructions that you may have to do that. So, I scribed it all out on the flanges and port matched my headers to the exhaust port. But, if you go look at any race motor. NASCAR, NHRA, etc... and you look at the headers. They aren't port matched, they in most cases are bigger than the exhaust port. You want to take those hot expanding exhaust gases and move them out as quickly as possible. The steps are so that as the gases cool, the port they travel gets smaller and you keep exhaust gas velocity up.

This may be wrong, but it is my understanding that on many of the headers for the LS1/LS6 the flange and tubes are in fact bigger than the port.

If that is the case then this would offer no flow restriction. So, changing the flange to a D Port is probably not going to really gain you anything. Even if the flange was a D Port, that is at most a 3/8" transition from flange to tube. At which point it is round anyway. But no one is going to make a D Port header tube.

So, like I said, the most important thing is just to make sure the port isn't obstructed, and then to make sure the tube isn't too big, and then to do your homework on number of steps, etc...

I would like S/S also. As I mentioned earlier. ATR supplies several different S/S exhaust systems for cars, include the GN. Everything I have seen asked for, they are capable of. Also they have an in house dyno, so they could validate any performance gains, just as many of the other vendors would. The construction, quality, and materials they use are simply the best.

All of their headers are 3/8" flange 304 S/S with mandrel bent tubes. Anyhow, I just thought I would throw this out there, as another option. If there was any interest we could see if they would fab some up for us.

Also in the other forums, it looks like LG is fabbing up some nice equal length headers in S/S that could also be quite promising.
 

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BLEUBYU said:
...Why not wait until these units are done with their relative power gain testing on the dyno, and then we will have more definitive info? I think we will know a lot more about this issue by the end of this year...
Oooh, I can address this issues!

...'Cause you can have incredible power gains NOW by strapping on a set of, say, TPIS long tubes NOW.

One thing that I think is very important to remember here is that we're all running different COMBO's of components on our cars, and some of these components work well together, and some don't. When you couple that with the fact that some of our cars come out of the factory with different performance levels, then perhaps the issue of waiting to see it 2 or 3 more HP can be gained from a set of headers becomes moot. What if you get more HP from your headers than I do, but my intake combo works better with my headers, giving ME more overall HP? Where are we then?

(Me, I don't have the time or money to flow-test everything before and/or after it goes on the car.)

The way I see it, the results of the testing of headers will vary on the strength of ones engine (stock) to begin with, and also any mods made ahead of (and after) the intake, too. Unless we can all agree that there's going to be ONE magical combination out there of intake and exhaust components, and that it's just a matter of time before we nail that down, then I think we could be chasing a pipe dream here.

Heck, even the NASCAR guys have to tinker with their set-ups every week -- and often many times during the week and/or race. Why? 'Cause sometimes an engine just isn't as strong as another, or a combo works better/worse on a given day, or the combo doesn't hold up long term, or... (etc.) And one of the reasons they don't inform the others of their proposed set-ups is 'cause they CAN differ (and not only could someone copy theirs, but they could IMPROVE on theirs). My point is just that there's no one magical combo out there, I'm convinced, and so looking for it MAY be futile. I think that includes header design, too.

That being said, I can FEEL a difference in my car now that I have "mass-produced" long tube headers on my car. I supsect a dyno would "prove" that difference, but until I can get it dynoed, I'll just accept that there is a difference. Oh, and I'm enjoying that difference NOW, and would recommend that others get the headers done now, too. Should anyone ever be satisfied that there can't be something better out there? No. Could you be enjoying real-world gains from some headers that exist now (and might you find that they're some of the best even AFTER these new designs come out)? Hell yeah! :D

-Kirk
 

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Whoooohooo! finally some people who agree with me!



<--- sportin' TPIS. :)
 

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Discussion Starter · #12 ·
Welll...that's what is so great about this forum, and for that matter - this country. We can entertain and exchange a wide diversity of opinions, and occasionally, just occasionally... some additions to our base of knowledge takes place.

Here's my take on the header deal. Between now and the end of the year including the Breathless product, there will be at least twice as many header products for us to squabble over as there are now! ;) Now, that's something - and what fun - and, well maybe the opportunity to add to our base of knowledge. I mean after all, squabbling over the intake stuff is gettin' old! We need new areas to fuss and opinionate over. And guess what, the temp is already dippin' below freezing down my way some nights, so the TOY really will not see a lot of action over the next few months.

So, here I be by the ol' fireplace, poppin' open a few

:guiness: and checking out all the new products and the tests of same. From my point of view, what's the rush to buy what is out there now? They will still be around in the Spring, and in a few months of cgitation, agitation and serious :guiness: , I can make THE CHOICE! :lol:

Hey, were havin' fun here! :D
 

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You people keep talking about this "snow" stuff...what's that?

:p
:cheers:
:guiness:
 

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This ought to make the header controversy even more interesting. Corsa Performance just inked a contract to make the headers developed by Wheel to Wheel Racing (WTW)-they make the C5R race cars-to market their headers. They shoudl be on the market by early next year and available in jet coated and uncoated. Also looking at stainless or TI.

With all the info on headers flying around, it will be interesting what Corvette Racing thinks is a good header. The questions still remain, what mods do you have, what RPM ranges do you run, how will run if you are using it on the street thru HP Cats, etc.

I think next year will be very exciting for mods on the Z06.

To add more fuel to the fire, it seems Skunk Werkes still uses the Donaldson Air cleanerfor the Z06 as their choice of air supply. Sojmetimes it is fun to live in Detroit--everyone knows someone who really knows!!!!
 

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Very interesting thread....I believe Mallett is currently developing new headers also. Does anyone know if Katech, Lingenfelter, or anyone else is doing the same?

Zippy :z: :z:
 

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Zippy

Since Katech is just around the corner from WTW and Skunk Werkes, they probably share much of the technology. One designs and builds prototypes, one builds race cars and one builds engines.
 

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Let's see those LGM headers fly now! bahahahaha!

:)

I talked with Lou at our local gathering last week, he showed up in their 7.0L FRC sportin' the new headers....they picked up something like 17 over the TPIS on the big cube....

Another buddy of mine install LG's headers on his stock motored LS1, picked up 27 rwhp.....best I've seen yet!

:cheers:
 

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Just my .02..........

Hi Forum,

Just my .02 about worrying about the D-port exhaust and port matching. If you think of the engine as a big air pump, of course you want maximum air in, max out. I don't think that you need to worry about port matching the exhaust side if the header opening diameter is bigger than the exhaust port. Why would you want someone to port the flange the same diameter as the exhaust?

1. It raises the cost of the exhaust, because porting is involved and it is labor intensive.

2. It would make installation harder, because everything would have to be lined up perfectly, and besides with the header on, how would you know if they were lined up perfectly.

Now, porting the intake is a different story, as even the 2001 LS-1/Z06 intake is still restrictive and can use all the help it can get.

Once again, this just my .02
 
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