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Directconnection
06-15-2007, 08:15 PM
I have a couple pages of the data written down from pages of flowtests, but I will give a rundown on just the flow gains/losses in cfm with the manifold bolted to the head, and at .500" lift. Also, I bolted the manifold down to exhaust runner #2 on the bone stock g-head and simply used the same head runner for all manifold runner tests (and blocking off the other runners of course) this way there was no variance of different head ports being used (and less math, too). Used the same exhaust head port for all tests. I also had a 3" spacer between the headstand and head for exhaust manifold clearance.

Stock G-head *alone* at .500" lift: 127.7 cfm

Stock exhaust manifold:
#1) 1.4 #2) -17.2 #3) 7.4 #4) 6.9

Vendor A ported stocker:
#1) 1.7 #2) -17.7 #3) 6.9 #4) 6.5

Moparzrule ported stocker:
#1) 5.1 #2) -15.0 #3) 9.8 #4) 20.5

Vendor C ported stocker:
#1) -.3 #2) -16.7 #3) 9.3 #4) 4.3

Vendor A log header:
#1) 3.1 #2) -5.8 #3) 1.3 #4) 11.1

Vendor B log header:
#1) 3.9 #2) -3.5 #3)no test #4) 10.9

Vendor C semi equal length header:
#1) -1.3 #2) -2.8 #3) -3.7 #4) 3.2

Vendor B *LOG HEADER* PORTED by Steve Mercier:
#1) 11.1 #2) 10.5 #3) 17.2 #4) 12.7



I also performed another flowtest on these manifolds on a SF-300 at 10",28" and 45" but never got around to crunching the #s and also had a few test situations with 45" creating so much heat that the tape on the other ports would vibrate off on some and I tried my best to keep an eye on. Doesn't appear that at 45" that they flow alot more air as I expected, but it does appear that they do flow more, especially the larger volume ports.

A 1 cfm gain over what the head flows is a pretty big gain to be asking of, so take these small flow increments in terms of more like a stock head that flows 140cfm, and a big valve head that flows 200+

BadAssPerformance
06-15-2007, 09:21 PM
Vendor C semi equal length header:

Nice study and information Steve! :thumb:

semi? ;)

Directconnection
06-15-2007, 10:27 PM
Nice study and information Steve! :thumb:

semi? ;)


Hehe... I say semi because I never measured to confirm it, but it does look close enough;)

nomadman2001
06-15-2007, 11:48 PM
I'm confused. The numbers are all over the place :yuck: , can you explain them a little for me?

Directconnection
06-16-2007, 09:00 AM
I'm confused. The numbers are all over the place :yuck: , can you explain them a little for me?


The #s aren't all over the place, but maybe it's a bit confusing for some as they are tight knit.

I 1st flowed a stock g-head exhaust port which happened to be cylinder #3 and was 127.7 cfm. I now had my baseline. Then, I put on the exhaust/intake gasket, put heavy tape on runners 2,3 and 4 on the exhaust manifold of choice for the test and bolted the open #1 runner to the head. Now, for the stocker, as you can see, flow picked up to the tune of 129.1 which was a *GAIN* of 1.4 cfm. Then, peeled off the tape on runner #2 and put new tape on #1 and tested #2 which lost 17.2.


See the pattern?

Frank
06-16-2007, 09:04 AM
Steve,
I dont think he is confused by your numbers and your method, but rather the reason why they do that.


Jim,
It has to do with header construction. Our flanges are placed such that the turbo actually fits. When you have to meet those demands, your runners are not equal and can very flow quite a bit.

moparzrule
06-17-2007, 06:22 PM
I take credit for the Vendor B ported stocker. Since steve has given me the results a little bit ago before this post I've calmed down the #4 runner porting to make it flow a little more even to the rest of the ports. I also spend a little more time in runner 2 to make it flow better as it is hands down the worst port in our stock manifolds. I've learned a lot from this test, and I want to thank steve very much for helping me improve my manifolds even more than what they are.

Directconnection
06-17-2007, 09:22 PM
I will change vendor B to your moniker.

Also, I edited my ported example as it was Vendor B, but Vendor B ported LOG header, not a ported moparzrule's manifold by me;) .

SwiftTech
06-19-2007, 01:24 PM
did you test a tbi header?

Ondonti
06-19-2007, 06:56 PM
did you test a tbi header?
You cant really use the flow numbers on individual runner manifolds to compare how well they will perform against a log.

Higher flow numbers on this test dont = more hp but you can notice that among the log style, some of them really suck with cylinder to cylinder flow so some people are trying to balance that out.

TBI header might flow less then anything else tested but that doesnt mean its going to lose power. The method of testing cant be used to compare log vs individual runner manifolds IMO but it does show how the individual is pretty balanced and it took work to fix a log manifold to balance it out (so maybe the log without porting is not such a great idea etc) The stock log headers still do a much better job of helping cylinder #2 flow.

SL#189
06-19-2007, 07:25 PM
So an optimal header/manifold would have equal flow through all runners independent of actual flow quantity (with the understanding that more flow is better)? Is it possible to do this with our stock manifolds?

Directconnection
06-19-2007, 07:44 PM
I could make a stocker flow close to the log header, but it would require welding, and I wouldn't trust it after that.

Also.... the stock manifold is a log manifold and much like the log headers except for lesser volume.

Lastly, an equal length or individual runner manifold has it's advantages. But... before we should care so much about tuning and it's effect of the pulses drawing other cylinders via scavenging during overlap (which may not be as critical as NA since we have little overlap and huge backpressure...but that's another story on it's own...) ....we shouldn't overlook that the meat and potatoes of the actual job the manifold has: and that's to move exhaust gasses through the port, 1st and foremost. Efficient engineering via proper tuning is the icing on the cake... and proably pretty thick, as well.

.

tvanlant
06-19-2007, 10:08 PM
Looks like the log headers flow much more evenly than any of the stockers, but still very nice numbers on Matt's.

Have the other vendors requested that this test be anonymous?

Directconnection
06-19-2007, 10:22 PM
Have the other vendors requested that this test be anonymous?

No, it was my doing. Also, most of them were collected samples, not vendor donated. Hint about the log headers...both are not being made anymore. So, it is not a TU that I tested.

johnl
06-19-2007, 10:51 PM
Seeing how much better #4 flows in this "static" measurement of flow by individual header port test, where the inertia and flow of cylinder #s 1,2 & 3 are not working against #4, makes me wonder whether #4 needs the extra flow to overcome the other 3. In a "dynamic" sense it is 3 against 1, pushing uphill.

It's another one of those - "if only we had back to back dyno test" - deals.

BadAssPerformance
06-19-2007, 11:46 PM
BTW,
Vendor C semi equal length header: is my prototype... "semi" cuz Steve did not measure them, but the runners are within .25" of each other...

In a static bench measurement it flows worse than a stocker, yet much more balanced. At 7000 rpm I think it works just a little better... dyno needed to prove this. :thumb:

http://www.badassperformance.com/mstore/bap_parts/header/header_01.jpg

cordes
06-20-2007, 12:02 AM
BTW, is my prototype... "semi" cuz Steve did not measure them, but the runners are within .25" of each other...

In a static bench measurement it flows worse than a stocker, yet much more balanced. At 7000 rpm I think it works just a little better... dyno needed to prove this. :thumb:

http://www.badassperformance.com/mstore/bap_parts/header/header_01.jpg


Do you think that the added bends needed to make it equal length are what causes the reduction in flow?

BadAssPerformance
06-20-2007, 12:13 AM
The pipes are just slightly larger cross sectional area than the ports, so adding length of a similar cross section (even without bends) adds restriction to flow. Velocity is maintained better tho...

moparzrule
06-20-2007, 06:27 AM
Seeing how much better #4 flows in this "static" measurement of flow by individual header port test, where the inertia and flow of cylinder #s 1,2 & 3 are not working against #4, makes me wonder whether #4 needs the extra flow to overcome the other 3. In a "dynamic" sense it is 3 against 1, pushing uphill.

It's another one of those - "if only we had back to back dyno test" - deals.


That was excatly the same point I said to Steve when we were first discussion this testing VIA PM's and he said he'd be testing each runner individually. But we concluding that testing all 4 at once simply couldn't be done on the flowbench plus it would take 10 times as much work to do it with all the fabrication needed so I wasn't expecting steve to do it that way. He's done enough IMO, this took a lot of work and he did it all for free so you won't hear complaints from me!
I already knew my manifold flowed better than and FM unit because it was my own personal experience and I had a friend do one of the old leaf blower test on mine against FM against a stocker. But that was flowing all four at once and for that reason he had to go backwards through the manifold. The test was just for kicks, but mine kicked FM's azz all over the place. But in my real world testing, I had 200-300 RPM faster spoolup and a definate seat of the pants upper RPM gain. Before that I never knew the manifold made such a difference. It might have been amplified because I was running close 300 WHP, perhaps a closer to stock car wouldn't have felt as much of a difference. But no other changes were made besides the manifold swap. Unfortunitely I never got to re-dyno because my car got totaled about 2 weeks after I changed the manifold. :yuck:

MiniMopar
06-20-2007, 10:50 AM
I have one of those leaf blowers that can double as a giant leaf sucker. If you hooked that up from the turbo end and measured negative inches of water at the turbo outlet, you could do a quick comparison while flowing all four runners. Not a scientific test for sure, but could test overall flow differences.

NeonShowCar
06-20-2007, 11:06 AM
BTW, is my prototype... "semi" cuz Steve did not measure them, but the runners are within .25" of each other...

In a static bench measurement it flows worse than a stocker, yet much more balanced. At 7000 rpm I think it works just a little better... dyno needed to prove this. :thumb:

http://www.badassperformance.com/mstore/bap_parts/header/header_01.jpg

Nice looking header JT. Are those 1 7/8" tubes? I'd be a little worried about that exhaust flange thickness looks like 1/4".

Still a nice looking header - ever run it on the car?

BadAssPerformance
06-20-2007, 01:14 PM
Nice looking header JT. Are those 1 7/8" tubes? I'd be a little worried about that exhaust flange thickness looks like 1/4".

Still a nice looking header - ever run it on the car?

Thanks... 1-5/8" tubes... has been on th ecar for several years, not a ton of miles tho. The flange started out at 1/4" but was a litle wavy after welding the tubes to it so I ground it flat... one side is ~ 1/8" now :eek: but it still seals pretty well :thumb:

johnl
06-20-2007, 04:41 PM
I have one of those leaf blowers that can double as a giant leaf sucker. If you hooked that up from the turbo end and measured negative inches of water at the turbo outlet, you could do a quick comparison while flowing all four runners. Not a scientific test for sure, but could test overall flow differences.

Dang, I just threw out an old swamp cooler. The motor and squirrel cage were still good. Now, that would have made a giant sucker!

moparzrule
06-20-2007, 05:44 PM
I have one of those leaf blowers that can double as a giant leaf sucker. If you hooked that up from the turbo end and measured negative inches of water at the turbo outlet, you could do a quick comparison while flowing all four runners. Not a scientific test for sure, but could test overall flow differences.


Good idea, but I'm not sure how much of an affect the sucking of air will make things different than blowing it throw like it does on the car.

MiniMopar
06-20-2007, 06:01 PM
Good idea, but I'm not sure how much of an affect the sucking of air will make things different than blowing it throw like it does on the car.

Shouldn't be much different, since it just a pressure differential. It's better than blowing through it backwards.

You could also block each port in sequence and compare the readings for a very rough comparison that way.

iTurbo
06-20-2007, 11:41 PM
How about the 'TBI' headers? How well do they flow compared to the log type manifolds out there?

BadAssPerformance
11-27-2007, 02:35 PM
For some reason I just thought about this thread.

If flow is measured like this, a smaller diameter and/or longer length will reduce the flow, right?

So an equal length runner manifold compared to a plenum would flow less if the cross sectional area of the (log) plenum is larger and the length is shorter than that of the the (equal length manifold) runner?

TurboRon25
11-27-2007, 02:46 PM
That is why I'm not a big fan of comparing manifolds based on flow tests.
If you flow all runners at the same time it is better, but you still don't take pulses into account.
Killing velocity also "flows" nice.

Flow test is great for stock vs ported stock A vs ported stock B

Ron

lansingsportsrage
03-17-2008, 09:51 AM
I am told that that the flex-fuel exhaust manifold and/or the Mexican MPI Exhaust Manifold (maybe they are two in the same) were stock cast iron header like manifolds which flowed exceptionally well.

Can anyone confirm ?

Directconnection
09-08-2010, 10:55 PM
Just bumping this thread from the dead for a friend (Jim) to see here ;)

RoadWarrior222
09-09-2010, 07:24 AM
Not sure if it was here or elsewhere, but it was one of those "Can I use a leafblower for boost?" threads, and doing the math, it turned out that with optimistic figures you might get a couple of PSI... so I wouldn't put too much stock in them for boosted flow numbers, but they might be useful for N/A testing.

Vigo
09-09-2010, 02:26 PM
How about the 'TBI' headers? How well do they flow compared to the log type manifolds out there?

I would say ask JT because a tbi header is laid out the exact same as his tubular manifold so balance between cylinders should be pretty similar.

cordes
09-09-2010, 04:08 PM
I would say ask JT because a tbi header is laid out the exact same as his tubular manifold so balance between cylinders should be pretty similar.

Could you expound upon that some more? The TBI and JT's piece look quite a bit different to me.

Also, I thought the TBI header info was out there. Perhaps it was posted up later in the thread?

Directconnection
09-09-2010, 05:08 PM
Not sure if it was here or elsewhere, but it was one of those "Can I use a leafblower for boost?" threads, and doing the math, it turned out that with optimistic figures you might get a couple of PSI... so I wouldn't put too much stock in them for boosted flow numbers, but they might be useful for N/A testing.


Let me ask you something then: would you rather have the ported ABM I did, or a stock-stocker? If by your reasoning, there shouldn't be any difference, if any at all.... right? ;)

I believe Ken and Reeves saw quite a bit of difference in their et/mph from running a stock unported ABM.

turbovanmanČ
09-09-2010, 06:57 PM
I believe Ken and Reeves saw quite a bit of difference in their et/mph from running a stock unported ABM.

What did they run previously?

Directconnection
09-09-2010, 08:31 PM
What did they run previously?

I don't recall the specifics, but I remember talking to ken on the phone years ago about the positive gains he saw.

Then going waaaaay back. (john?) Johnston who was a former SDAC president many years ago used to road race his pretty much stock '87 GLHS. He went with the "new for then" FM header, which was the TBI modded setup. I don't want to put out #s that I seem to recall he said he saw.... but it was a LOT for that single mod. I'd have to say it was probably optimistic.... but still a good gain.

Now, let's keep this on topic and not ruin the factual info by bench racing and saying a ported stocker is the shiznay! :D

turbovanmanČ
09-09-2010, 08:33 PM
I don't recall the specifics, but I remember talking to ken on the phone years ago about the positive gains he saw.

Then going waaaaay back. (john?) Johnston who was a former SDAC president many years ago used to road race his pretty much stock '87 GLHS. He went with the "new for then" FM header, which was the TBI modded setup. I don't want to put out #s that I seem to recall he said he saw.... but it was a LOT for that single mod. I'd have to say it was probably optimistic.... but still a good gain.

Now, let's keep this on topic and not ruin the factual info by bench racing and saying a ported stocker is the shiznay! :D

Fine, :mad: :p

BadAssPerformance
09-09-2010, 09:11 PM
I would say ask JT because a tbi header is laid out the exact same as his tubular manifold so balance between cylinders should be pretty similar.


Could you expound upon that some more? The TBI and JT's piece look quite a bit different to me.

Also, I thought the TBI header info was out there. Perhaps it was posted up later in the thread?

First off, there are several problems with a flow bence test comparisson between manifolds for turbocharged applications.

In a simple flow test the measurement is the restriction of the port combined with the length of the runner, so to do good on a flow test you just need a big hole. A header made with soup cans for primaries and a log plenum made from 2 coffee cans welded end to end would outflow all headers, but probably not perform as good as any other header.

Some race headers have looooong primaries to tune the exhaust pulses for a specific RPM. These can work well, but would provide poor flow test results.

See the pattern here?

The TBI has balance but the cross section of the runner has restrictive cross section and tight bends so it does restrict flow. The header I made has larger ID pipes and larger, smoother radius bends to try to help the flow over the runner lengths.

Really would have to do a back to back analysis to see, but my money is that the tube header will out perform the TBI header and not cuz I am biased to hell either, LOL.

Vigo
09-09-2010, 09:39 PM
The TBI and JT's piece look quite a bit different to me.

How so? The runners are routed the exact same.. although most people who make tbi headers dont weld the flange on at the same angle as JT's header (which is their mistake imo).



The TBI has balance but the cross section of the runner has restrictive cross section and tight bends so it does restrict flow. The header I made has larger ID pipes and larger, smoother radius bends to try to help the flow over the runner lengths.

Really would have to do a back to back analysis to see, but my money is that the tube header will out perform the TBI header and not cuz I am biased to hell either, LOL.

I completely agree with you.. I think anyone with a better than stock head and intake would benefit from running your header over a tbi header.

BadAssPerformance
09-09-2010, 09:44 PM
How so? The runners are routed the exact same.. although most people who make tbi headers dont weld the flange on at the same angle as JT's header (which is their mistake imo).

Like...


The TBI has balance but the cross section of the runner has restrictive cross section and tight bends so it does restrict flow. The header I made has larger ID pipes and larger, smoother radius bends to try to help the flow over the runner lengths.

Vigo
09-09-2010, 10:18 PM
The only reason i brought it up was because of balance.. Im not contesting the flow part.. you saw the 2nd part of my post?

cordes
09-09-2010, 10:46 PM
Perhaps it's just me, but JT's piece looks different in my mind than a TBI header. Isn't Aaron's piece patterned off of JT's design?

8valves
09-09-2010, 10:48 PM
Perhaps it's just me, but JT's piece looks different in my mind than a TBI header. Isn't Aaron's piece patterned off of JT's design?

More or less. Really it was just the easiest way to get close to an equal runner length with the shortest amount of time, effort, and cost of materials involved. And since I built mine out of spare scrap bends that was important, haha!

Had I been smarter I would've looked at JT's more closely to make a more extreme angle into the turbine housing so it would clear the firewall easily. The coolant fittings on my turbo have an interference issue. Or, had, rather. :p

cordes
09-09-2010, 10:50 PM
More or less. Really it was just the easiest way to get close to an equal runner length with the shortest amount of time, effort, and cost of materials involved. And since I built mine out of spare scrap bends that was important, haha!

Had I been smarter I would've looked at JT's more closely to make a more extreme angle into the turbine housing so it would clear the firewall easily. The coolant fittings on my turbo have an interference issue. Or, had, rather. :p

A two minute response time after not seeing you post for months. Nice. :clap:

8valves
09-09-2010, 10:53 PM
A two minute response time after not seeing you post for months. Nice. :clap:

HAHA! I can't even begin to explain how busy I've been with work. It's so crazy (thankful!) that I haven't had any time to work on any of my stuff at all.

Not to mention I've been working on a project for a member on here FOREVER now. I can't thank him enough for being so patient. But I'm sure he'll share that with everyone soon enough.

cordes
09-09-2010, 11:00 PM
HAHA! I can't even begin to explain how busy I've been with work. It's so crazy (thankful!) that I haven't had any time to work on any of my stuff at all.

Not to mention I've been working on a project for a member on here FOREVER now. I can't thank him enough for being so patient. But I'm sure he'll share that with everyone soon enough.

I'll look forward to seeing the pics. It's actually killing me that I'm going to be in your hood next week, but I'll be super busy at a wedding so I won't be able to stalk your progress at all.

black86glhs
09-10-2010, 03:38 AM
Steve....my ported ones will have mad flo skilz yo!!!!:clap:




Sorry, couldn't resist wasting bandwidth.;):D

Pat
09-10-2010, 12:22 PM
Then going waaaaay back. (john?) Johnston who was a former SDAC president many years ago used to road race his pretty much stock '87 GLHS. He went with the "new for then" FM header, which was the TBI modded setup. I don't want to put out #s that I seem to recall he said he saw.... but it was a LOT for that single mod. I'd have to say it was probably optimistic.... but still a good gain.


I wish I had some hard data to contribute, however, I can say this...

I bought John J's GLHS a couple of years ago. I haven't done much with it yet, nor have I changed the engine set up at all from what John had and I can say that for a mostly stock set up with FM's tbi header, MP Stage II computer and 2.5" exhaust with a cat, that car boogies. It is definitely faster than my first GLHS was with a similiar set up minus the header.

John gave me a folder filled with documentation on the car, and in it were a bunch of timeslips where he was consistely trapping 102 mph on street tires. For that set up, that's pretty good. I think the header has a lot to do with that.

Directconnection
09-10-2010, 12:37 PM
I wish I had some hard data to contribute, however, I can say this...

I bought John J's GLHS a couple of years ago. I haven't done much with it yet, nor have I changed the engine set up at all from what John had and I can say that for a mostly stock set up with FM's tbi header, MP Stage II computer and 2.5" exhaust with a cat, that car boogies. It is definitely faster than my first GLHS was with a similiar set up minus the header.

John gave me a folder filled with documentation on the car, and in it were a bunch of timeslips where he was consistely trapping 102 mph on street tires. For that set up, that's pretty good. I think the header has a lot to do with that.

Pat, that *IS* really good info! So I'm not crazy (ok, well...sorta:D) For those that also don't remember (or go back far enough) Pat's GLHS ran high 12s.

Pat
09-10-2010, 01:06 PM
Pat, that *IS* really good info! So I'm not crazy (ok, well...sorta:D) For those that also don't remember (or go back far enough) Pat's GLHS ran high 12s.

Ahem....mid 12's ;)

On the tbi header GLHS, I think the rest of the set up (again, I didn't build it but from what I recall from receipts) is a fresh 2.2, an UDP, the FM header, 2.5" exhaust with cat, stock cam, and an E1 turbo, which I'm almost positive is a .48 exhaust/60 trim compressor. As far as I know, the head, cam and intake are stock stuff.

Now, you can argue that some of the gains are form the turbo, however, in my first GLHS, it was trapping a consistent 110 mph on a stock turbo. I did swap on a .48/60 trim turbo as a test to see if it would pick up anything and it really did not. Trap speeds remained at the 110 mark, which I attributed to the stock exhaust wheel in a .48 housing.

That being said, the turbo on the tbi header GLHS is likely not giving any real improvements over the stocker. The big modification on that car is definitely the header.

8valves
09-10-2010, 02:51 PM
Ahem....mid 12's ;)

On the tbi header GLHS, I think the rest of the set up (again, I didn't build it but from what I recall from receipts) is a fresh 2.2, an UDP, the FM header, 2.5" exhaust with cat, stock cam, and an E1 turbo, which I'm almost positive is a .48 exhaust/60 trim compressor. As far as I know, the head, cam and intake are stock stuff.

Now, you can argue that some of the gains are form the turbo, however, in my first GLHS, it was trapping a consistent 110 mph on a stock turbo. I did swap on a .48/60 trim turbo as a test to see if it would pick up anything and it really did not. Trap speeds remained at the 110 mark, which I attributed to the stock exhaust wheel in a .48 housing.

That being said, the turbo on the tbi header GLHS is likely not giving any real improvements over the stocker. The big modification on that car is definitely the header.

And to help with that, my Daytona traps 108.0-108.2 every time. That's a power everything Shelby Z in FL heat/humidity on a stock longblock. MP ecu, 3", my header, 2.25" SV, .63 exhaust housing, FMIC, +20's/AFPR. 20 psi. No other tricks. I've never had a stock turbo L body really to compare. But I just bought one last week, so I may test out this driveline combo in there.

EDIT: Car ran 105.7 mph average before header in good cool weather. 108.1 AVG after in crappy weather. That actually is fairly significant down here, I've found.

GLHNSLHT2
09-11-2010, 10:24 AM
aaron, no cracks in the header yet? Are you supporting your turbo? Do you daily drive it? I drove my daytona for 3-4 months with the JRB header. It's now a warped cracked up POS sitting on the shelf. I'm not happy about it but loved the way it ran with it. $750 down the drain. My 8v head is going onto my 2.2 new yorker with the modded 2 piece and a ported stock exhaust manny and the S60 turbo. I hope it runs close to the same as it did on the 2.5 with the header.

8valves
09-11-2010, 12:13 PM
aaron, no cracks in the header yet? Are you supporting your turbo? Do you daily drive it? I drove my daytona for 3-4 months with the JRB header. It's now a warped cracked up POS sitting on the shelf. I'm not happy about it but loved the way it ran with it. $750 down the drain. My 8v head is going onto my 2.2 new yorker with the modded 2 piece and a ported stock exhaust manny and the S60 turbo. I hope it runs close to the same as it did on the 2.5 with the header.

Nope, no cracks. I daily-drive it on/off switching with the truck, depending on the weather. I have around 6000 miles on it and about 40 passes at the track. Every time I drive it I beat the snot out of it too. As well as a few 2-3hr constant freeway drives.

No bracing. No additional "strength tabs", and only single pass welds on everything on it.

304SS 16 gauge tubing welded with 308L rod and mild steel flanges (came from TU, same thickness as their old welded headers), welded with 309L to adjoin to the SS. Everything backpurged at all times while welding. Stock swingvalve style donut for a flex section.

Sorry to hear that about your header. I remember looking over the pictures on it. Sadly, in this line of work as well as many others, outside appearance isn't everything.