Header questions

[freakstatus]

Is there much difference in performance when you just install the Kooks headers by themselves with the stock exhaust? Or do you need the entire Kooks exhaust and X pipe to see the difference?

Also, when you install the Kooks headers, do you need a tune for them?

[mmssdriver]

you wont feel the full benifits of the headers until you complete the exhaust system, but you probably wont hurt anything cept ur pocket..

[sailsmen]

It will prob run lean.

[red]

It will prob run lean.
Headers will cause a car to run rich, as the 02 sensor will detect excess air (a lean condition) and instruct the PCM to provide more fuel. My A/F after header install went to the mid 12's.

[snowbird]

You have to do the whole system for sizeable benefit but it will cost quite a bit $$ and you'll have to stand the added noise.

IMO, you have to seriously consider a blower as for a little more money you get a whole lot more HPs and TQs ...

[sailsmen]

06-14-2005, 03:06 PM

Ken
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Go For It!!!
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Quote:
Originally Posted by Yamaha
Hi, I'm close to going the kooks full system route. Couple questions: Did you do the 1 3/4 or 1 5/8 diameter pipes and is there an exhaust drone at speed (80mph) ? I've go the 4.10's, Lidio chip and CAI. I'm in New Jersey and can drive to Kooks in LI for a local install. Thanks, Stan
I just got my 4:10 's last week; with the Lidio chip, CAI, and the Kook's full system. It is a pleasant sounding exhaust, I don't notice any drone. You won't be sorry. Go for the larger pipes, let it breathe!
Note: you may need to get dynoed and the A/F ratio adjusted, I didn't notice it after the Kook's, but I did after the JLT CAI install. Lidio said that it was about 13.7-13.8, instead of about 13.0.
Ken
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03-03-2008, 10:48 AM

Local Boy
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Having the mods you listed (Kooks) puts your motor in the lean side of the A/F ratio...Moreover, the dealership may have put in cheap gas...and the motor goes down hill from the time you drive off the lot...The "Ting" you heard was actually "Ping" as in detonation...OUCH!

You say the car was running awesome...that is because it was running very lean.

Bottom line: Bad gas + those mods = Lean condition (engine damage)

You may be in a good position to get a new motor! I would push for that...

Good Luck...Don't give up...it really is a GREAT car...

ALOHA
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05-22-2006, 09:46 PM
Lidio
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Quote:
Originally Posted by MADDOG
Lido,

I have a Xcalibrator2 that i bought from you. I recently installed my Kooks headers. Is the the 4:10 tune already set for headers? If not, what adjustments should i make with my progamer? Should i adjust my air/fuel ratio?

Current mods installed:
4:10 gears W/STUD GIRDLE
JLT RAM INTAKE
KOOKS HEADERS/BASSANI X-PIPE/SUPER 40'S/DELETE TIPS
You really should get the A/F checked now that you've installed headers and probably a 2.5" exhaust of some sort. Believe it or not, the A/F on some cars doesn't go that lean or lean enough to worry about at WOT with a header and exhaust install. But its best to get it looked at.

You may want to have your A/F hecked again. How was the A/F checked a sniffer or bung?

[MarauderTJA]

Headers will cause a car to run rich, as the 02 sensor will detect excess air (a lean condition) and instruct the PCM to provide more fuel. My A/F after header install went to the mid 12's.

Was that on a dyno or data logged during a 1320 run? Mid 12's with A/F is not really rich. For safety purposes with a stock motor with long tubes and exhaust I would have the car retuned.

[Paul T. Casey]

Is there much difference in performance when you just install the Kooks headers by themselves with the stock exhaust? Or do you need the entire Kooks exhaust and X pipe to see the difference?

Also, when you install the Kooks headers, do you need a tune for them?

Just my recomendation here. Do the "whole breathing" thing at once. By that I mean headers, high flow cats and mufflers (I like the Magnaflows), X pipe, tail pipes, and CAI and spacers. The CAI (and spacers if desired) is relatively cheap, especially when compared to the exhaust mods. But, by doing it all at once, you save the cost of tuning twice. The exhaust mod itself may or may not cause you a CEL condition, but it will alter the oxygen content your O2 sensors see. So yes, to get the most bang out of the exhaust mod, do a tune. By flowing the exhaust more freely, you can add air to the engine. The best way to do this is to unrestrict airflow to the TB. This is where you want to go with a CAI (again, personally I like the JLT). It's also a good time to jump up to the 90mm MAF (again, relatively cheap). What all this (intake and exhaust mods) has done is increased the air flow efficency of your engine. To realize the most potential of this air flow, you will need to re-tune. If you do all the above, I will garuntee you get a CEL. I'll even go as far as garuntying (sic) the codes will be P1195 and P1197. This translates as over lean on rear O2's. This will cause the PCM to add fuel to compensate for this condition, causing your engine to run rich and quite frankly, rather flat. What you need your tuner to do is re-do your fuel maps (there's plenty of room in the stock injectors to handle these mods) and either turn off the rear O2's or re-program them to like what's flowing by with the new tune. I'd rather not be sharing this info, as someday, someone will listen and I'll pay for it at the track, but being Easter and all, I'm in a generous mood today.

[red]

Believe it or not, the A/F on some cars doesn't go that lean or lean enough to worry about at WOT with a header and exhaust install. But its best to get it looked at.

Your LTFT (Long-Term Fuel Trim) is adapted according to your STFT (Short-Term Fuel Trim), which is richer as a result of the lean condition during closed-loop. These adjustments are applied during open-loop, as your 02 sensors cannot be used for feedback. Therefore, the car runs richer. Here's info on Fuel Trims (http://www.musclemustangfastfords.com/tech/0607mmfp_ford_efi_system_tunin g/index.html).


Was that on a dyno or data logged during a 1320 run? Mid 12's with A/F is not really rich. For safety purposes with a stock motor with long tubes and exhaust I would have the car retuned.

This was read on a dyno with a wideband in a tuning-only bung in front of cat on the driver's side. Dipped into the low 11's, but averaged out at 12.6. Mid 12's is rich for N/A, not rich for forced induction, as you would want to account for possibility of bad gas and other factors.


This translates as over lean on rear O2's. This will cause the PCM to add fuel to compensate for this condition, causing your engine to run rich and quite frankly, rather flat.

Agreed.

[Paul T. Casey]

Red, your Fuel Trims link no wrky for me.

[freakstatus]

Good stuff. Thanks guys. So I'd be looking at about 2 grand for the entire system?

[Kennyrauder]

I love my kooks & the magna flows with large exhaust. Just make sure you don't use the kooks header gaskets... mine blew out in a year. Go with the OEM manifold gaskets. Good Luck. PS the exhaust mod is a must if you S/C your car.

[red]

Red, your Fuel Trims link no wrky for me.
Paul, sorry. I fixed the link.

[Paul T. Casey]

Thanks Red. Awesome stuff there. Should be required reading for everyone who does any intake/exhaust mods.

[GreekGod]

PS the exhaust mod is a must if you S/C your car.

As I recall, at one time, the worlds quickest Marauder had a stock exhaust, including cast iron exhaust manifolds. Oh, and it was supercharged.

[red]

Thanks Red. Awesome stuff there. Should be required reading for everyone who does any intake/exhaust mods.
Posted here (http://www.mercurymarauder.net/forums/showthread.php?t=42854) so it could get a little more visibility.

[sailsmen]

The O2 sensors cut off @WOT. Headers reduce back pressure and increase scavenging.

At WOT with Headers a lean condition can result.

[red]

The O2 sensors cut off @WOT.

Your LTFT (Long-Term Fuel Trim) is adapted according to your STFT (Short-Term Fuel Trim), which is richer as a result of the lean condition during closed-loop. These adjustments are applied during open-loop, as your 02 sensors cannot be used for feedback. Therefore, the car runs richer. Here's info on Fuel Trims (http://www.musclemustangfastfords.com/tech/0607mmfp_ford_efi_system_tunin g/index.html).
Sailsmen, please read my post again. I stated this (open loop occurs under WOT).


Headers reduce back pressure and increase scavenging.
The efficiency is dependent on several factors of design in the headers.


At WOT with Headers a lean condition can result.
I disagree that this would be typical. Please back your statement with further explanation.

[sailsmen]

With LTH the scavenging can result in a lean condition. The operative word being can. The O2 sensors are off at WOT and uncombusted gas can be sucked out.

LTH are several times ($850-$950) the cost of having the A/F checked on a Dyno.

Point being if I had LTH put on a Marauder I would have the A/F checked. I know of several tuners who make the same reccomendation.

A better response is "You should probably have the A/F checked because it can run lean".

The questions was did he need a tune. The answer is get the A/F checked.

[red]

With LTH the scavenging can result in a lean condition. The operative word being can. The O2 sensors are off at WOT and uncombusted gas can be sucked out.
A clean intake charge is one of the benefits of headers. Too much valve overlap and too much exhaust velocity can result in excessive charge passing into the exhaust. With stock cams and headers / exhaust designed for our cars, this effect should be minimized.


Point being if I had LTH put on a Marauder I would have the A/F checked... The questions was did he need a tune. The answer is get the A/F checked.

Agreed. I had mine checked after doing the headers and exhaust.

[sailsmen]

Although unlikely in an N/A in an S/C there is a chance the fuel sys could max out with headers.

There was a header design that was highly efficient at scavaging utilizing a unique collector. Apparently it was difficult to tune and is no longer used.

It would be intersting to chart the exhaust pulse pre and post header install superimposed on a Dyno pre and post.

It would be a good graphic on how headers work.

[Dragcity]

I'll be doing a Kooks install as soon as I get them. I don't think I can afford multiple Dyno runs though.

[red]

Although unlikely in an N/A in an S/C there is a chance the fuel sys could max out with headers.
Again, on stock cams and using headers tuned for our car, it is unlikely that there is enough valve overlap to suck a significant amount of intake charge into exhaust. If there were a significant amount, then the 02 sensor would detect an increase in oxygen content from the passing of intake charge and therefore send a lean condition. This is the same point I made concerning the lone addition of headers without significant passing of intake charge. The increased oxygen content is read by the O2 and detected as a lean condition. Accordingly, the STFT is adjusted to richen the A/F and your adaptive trim (LTFT) is consequently and subsequently updated. The LTFT is used in our cars to modify the maps for open-loop (i.e., at WOT). Addressing your comment, which is inline with my statements: if your fuel system is almost maxed, then the addition of headers could cause it to max out. However, this does not necessarily mean that you are lean, as the car is already richer than necessary.


It would be intersting to chart the exhaust pulse pre and post header install superimposed on a Dyno pre and post.
We could try to compare the power and torque results of different headers, but what you stated does not appear to provide insight into the arrival timing beyond what you could see by comparing pre and post, and in my opinion, nor will it expose any valuable information to readers.

[Glenn]

Well here come the flames :flamer:.

Regardless of the dyno numbers the real track numbers do not strongly support tube headers on a SC as being absolutely necessary for good times. Look at the top 12 runners on the Timeslip page. Tube headers are not a requirement to run good SC times: two cars did not have tube headers - one was Lidio and one other guy.

Sorry fellows, but if you have a SC track times just do not support the high cost of tube headers and the custom X-pipe, etc. that people believe they should install as part of the "package". (I would not state this before due to my respect for a former Atlanta car shop owner.)

Yes, the extreme MM runners running low 11's and 10's seem to benefit more with tube headers, but I am talking about the average MM performance owner. Facts are facts - look at the track times. You do not need tube headers and the high cost of the entire exhaust package to run good times with a SC. (NA do run better with tube headers, but I am talking about SC MM.) If you want good dyno numbers and impress the guys then the headers are great. But, its performance on the street or track that count. FRPP Cobra shorty headers and a Cobra hi-flow X-pipe into your stock mufflers and exhaust pipes for your SC do just fine especially if you are on a limited budget.

OK, let the :flamer:begin.


Glenn

[red]

Well here come the flames :flamer:. Regardless of the dyno numbers the real track numbers do not strongly support tube headers on a SC as being absolutely necessary for good times.

No flames necessary; they'll only detract from the information here. Kennyrauder just stated his opinion. There are many ways to get a S/C car fast; headers does not need to be one of them.

[sailsmen]

Glen I am confused over what you are trying to say.

What do you mean by good times?

When you say tube headers do you mean Long or Mid vs the Ford FRP Short?

If you are referring to Lidio's time I believe that was w/ NO2 which has more O2.

I ran 12.2 w/o headers w/ Cobra Exhaust @10psi.

[sailsmen]

"The Exhaust Pulse
To gain a more complete understanding of how mufflers and headers do their job, we must be familiar with the dynamics of the exhaust pulse itself. Exhaust gas does not come out of the engine in one continuous stream. Since exhaust valves open and close, exhaust gas will flow, then stop, and then flow again as the exhaust valve opens. The more cylinders you have, the closer together these pulses run.

Keep in mind that for a "pulse" to move, the leading edge must be of a higher pressure than the surrounding atmosphere. The "body" of a pulse is very close to ambient pressure, and the tail end of the pulse is lower than ambient. It is so low, in fact, that it is almost a complete vacuum! The pressure differential is what keeps a pulse moving. A good Mr. Wizard experiment to illustrate this is a coffee can with the metal ends cut out and replaced with the plastic lids. Cut a hole in one of the lids, point it toward a lit candle and thump on the other plastic lid. What happens? The candle flame jumps, then blows out! The "jump" is caused by the high-pressure bow of the pulse we just created, and the candle goes out because the trailing portion of the pulse doesn't have enough oxygen-containing air to support combustion. Neat, huh?

Ok, now that we know that exhaust gas is actually a series of pulses, we can use this knowledge to propagate the forward-motion to the tailpipe. How? Ah, more of the engineering tricks we are so fond of come in to play here.

Just as Paula Abdul will tell you that opposites attract, the low pressure tail end of an exhaust pulse will most definitely attract the high-pressure bow of the following pulse, effectively "sucking" it along. This is what's so cool about a header. The runners on a header are specifically tuned to allow our exhaust pulses to "line up" and "suck" each other along! Whoa, bet you didn't know that! This brings up a few more issues, since engines rev at various speeds, the exhaust pulses don't always exactly line up. Thus, the reason for the Try-Y header, a 4-into-1 header, etc. Most Honda headers are tuned to make the most horsepower in high RPM ranges; usually 4,500 to 6,500 RPM. A good 4-into-1 header, such as the ones sold by Gude, are optimal for that high winding horsepower you've always dreamed of. What are exhaust manifolds and stock exhaust systems good for? Besides a really cheap boat anchor? If you think about it, you'll realize that since stock exhausts are so good at restricting that they'll actually ram the exhaust pulses together and actually make pretty darn good low-end torque! Something to keep in mind, though, is that even though an OEM exhaust may make gobs of low-end torque, they are not the most efficient setup overall, since your engine has to work so hard to expel those exhaust gasses. Also, a header does a pretty good job of additionally "sucking" more exhaust from your combustion chamber, so on the next intake stroke there's lots more fresh air to burn. Think of it this way: At 8,000 RPM, your Integra GS-R is making 280 pulses per second. There's a lot more to be gained by minimizing pumping losses as this busy time than optimizing torque production during the slow season."
http://www.nsxprime.com/FAQ/Miscellaneous/exhausttheory.htm

Header info.;
http://www.nhra.com/dragster/1999/issue04/racing_technology.html
http://www.carcraft.com/techarticles/header_basics/index.html

[red]

...
http://www.nsxprime.com/FAQ/Miscellaneous/exhausttheory.htm

Sailsmen, all fine and good and already understood. Pasting this does not suffice in explaining your point and just circumvents discussing your suggestion for graphing. So again, I'll ask, what value does overlaying the pulse count on a dyno printout provide? Do the pulses not grow linearly with the RPMs? My point is that you can overlay the dyno sheets of a stock Marauder with manifolds and a stock Marauder with headers, and point out the gains or loses, which would indicate the timing of arrival for the suction (scavenging) wave and determine where these headers are effective in the RPM range. And, as I mentioned, this could be of value if you're trying to compare header design (for example, take a look at the link you provided (http://www.carcraft.com/techarticles/header_basics/photo_02.html)).

[sailsmen]

As an illustration to explain how headers work for the benefit of the other 3,986 members who may find it informative.

The value of knowledge would be based on what benefit the recipient has placed on it.

[sailsmen]

Here are some interesting posts about the Shorty and Kooks;
http://www.mercurymarauder.net/forums/showthread.php?t=5946&highlight=kooks+shorty

06-15-2004, 11:26 PM
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Quote:
Originally Posted by cutt
what does the kit consist of.i'm interested in just removing my cats.(off road kit).will that kind of effect will that have on the computer?

Nothing...and unless your car is only off-road....it's illegal, and I wouldn't recommend posting it in a public forum.

There are 3 choices for exhaust changes in a "package".
Dennis' Cobra manifolds (replacement manifolds, hi-flo cats & x-pipe) still needs mods to the mufflers
Kooks Headers (complete kit through mufflers into the tailpipes, including X-pipe, hi=flo cats & 18" Magnaflow SS mufflers)
SVO Shorty Headers (available several places online since vendors here no longer sell them) then you'd need to have x-pipe and hi-flo cats fabbed or use other "off the shelf" versions

All three, have shown almost exacting gains on N/A cars.

--------------------------------------------------------------------------------
Last edited by TAF : 06-15-2004 at 11:28 PM.

http://www.mercurymarauder.net/forums/showthread.php?t=10718&highlight=kooks+shorty

09-23-2003, 02:33 PM
Logan
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Kook's Headers Dyno Results!!

--------------------------------------------------------------------------------

Wow!

I just got back from doing the post-dyno on my car with the Kook's exhaust on and was so excited I just can't contain myself!

Wow! (It bears repeating)

The only caveat I have to mention is that my car has a 3000rpm stall in it, so getting number much below 4000rpm is near impossible on a dyno. BUT, I can tell you, the newly available amount of power and torque down low launches my car like you wouldn't believe out of the hole.

That being said, my car prior to the header install, was making 256.3rwhp and 278.6rwtq.

My car, post header install is now making....

285.7rwhp and 293.5rwtq!!

That's peak, 29hp and 15tq!!

What's important to examine is that although the peak numbers are high, there are even higher spreads in the torque and power bands throughout the curve. There's almost a 50hp spread on power at 6000rpm!!!

All in all, what a kick ass investment!!
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Last edited by Logan : 09-23-2003 at 02:50 PM.

http://www.mercurymarauder.net/forums/showthread.php?t=5053&highlight=kooks

[red]

As an illustration to explain how headers work for the benefit of the other 3,986 members who may find it informative.

The value of knowledge would be based on what benefit the recipient has placed on it.
Agreed. A thorough and accurate explanation of how headers work would be an excellent article for the MyMarauder.com Wiki. The question was about why you were suggesting the graph of exhaust pulses overlaid on a dyno sheet. As I don't see this conversation being productive anymore, I no longer care to pursue the answer.

[Paul T. Casey]

No dyno numbers on hand, but I do have my timeslips book. Generally, with just the tune, u/d's, T-stat and plugs I went from 15.0x to 14.7x average with a best in the 14.5 range. Add complete (to tailpipes) exhaust (Kooks) and my average dropped to the 14.27 range, with best of 14.18. Polish, spacers, CAI, and re-tune brought me down to 14.0 average with best of 14.02. The exhaust itselve works. The tune makes it better.

[sailsmen]

For the benefit of the other 3,986 members who maybe interested;

"It would be intersting to chart the exhaust pulse pre and post header install superimposed on a Dyno pre and post.

It would be a good graphic on how headers work."

"As an illustration to explain how headers work for the benefit of the other 3,986 members who may find it informative.

The Dyno Graphs are the effect. The change in pulse is the cause.

[Glenn]

I was trying to explain that SC long tube headers are not necessasry to run in the high 11s. Also, I do not believe they are cost effective for the track times you can obtain if you are on a racer's budget. For half the cost you can install Cobra shorty headers and a hi-flow X-pipe and still run good times.

Glenn :burnout:

PS: I ran 13.9s with the same shorty headers and OEM mufflers and tail pipes before I went Trilogy.

[red]

The Dyno Graphs are the effect. The change in pulse is the cause.
Timing of arrival of the suction/scavenging wave (i.e., what's reflected in the collector due to pulse collisions) causes the changes in power/torque. What you suggested was:

It would be intersting to chart the exhaust pulse pre and post header install superimposed on a Dyno pre and post.
Per the definition you provided from the NSX FAQ, an exhaust pulse is described as:

Exhaust gas does not come out of the engine in one continuous stream. Since exhaust valves open and close, exhaust gas will flow, then stop, and then flow again as the exhaust valve opens... exhaust gas is actually a series of pulses
Therefore, an exhaust pulse is created as the result of every exhaust cycle and charting the pulses over the RPM range will provide no insight as every cycle produces one. Therefore, as RPM climbs, the number of exhaust pulses will climb linearly, providing no useful information.

Wave tuning, the basis of header design, times the arrival of the scavenging/suction wave such that it coincides with the valve overlap and draws a clean intake charge into the cylinder. The variables of design include the diameter and lengths of primary tubes and the diameter and length of the collector, and these variables are used to tune where power and torque are created. Comparing pre and post header install dyno sheets would provide insight as to how your header design has affected the location and amount of gains and could be used to compare multiple header designs. Again, for example, take a look at the link you provided (http://www.carcraft.com/techarticles/header_basics/photo_02.html).

[red]

The exhaust itselve works. The tune makes it better.
Agreed. With my full exhaust done, I was running in the low 14's. After dyno tuning (and adjusting my A/F), I was in the mid 13's.

[Kennyrauder]

WE all have to take an impromptu trip every now & again. OR WE WILL ALL BE TOTALLY NUTS>

[Kennyrauder]

I thought long & hard about going with Headers after the install of the Vortech but I really believe what goes in must come out. This engine is a breather compared with GM engines & I beg someone to tell me I'm wrong especially approaching 5 Grand. If you don't believe me I'll take you for a ride. C'mon up to Canada for a beer.

[sailsmen]

Comparing the pulse pre and post header will show a difference.

Superimposing this on a Dyno graph that also shows the pre and post will show the cause and effect. If they were the same value they would be either all cause or all effect.

It's a pulse.

Are you saying the pulse is the same before and after headers?

[red]

It's a pulse.
You have yet to clarify what it is you intend to plot over (or versus) RPM. What is your other axis? By simply saying "pulse", am I to assume the pulse count? If so, there's no value. If you're talking about another parameter of the pressure wave, please relate to the timing of arrival (typically done through simulation using the parameters of design). And again, what exactly will this tell the reader above what they can see by simply overlaying the pre and post dyno.

[sailsmen]

It's not the values it's the cause and effect.

There's a before and after.

[red]

It's not the values it's the cause and effect.

Then what exactly are you planning to superimpose on the dyno graph? Related to causality, should you also include intake, compression, and power strokes as causes of the exhaust stroke and pulse? I'm trying to understand what you're suggesting, so why not provide a mock-up?

[Paul T. Casey]

Well here come the flames :flamer:.

Regardless of the dyno numbers the real track numbers do not strongly support tube headers on a SC as being absolutely necessary for good times. Look at the top 12 runners on the Timeslip page. Tube headers are not a requirement to run good SC times: two cars did not have tube headers - one was Lidio and one other guy.

Sorry fellows, but if you have a SC track times just do not support the high cost of tube headers and the custom X-pipe, etc. that people believe they should install as part of the "package". (I would not state this before due to my respect for a former Atlanta car shop owner.)

Yes, the extreme MM runners running low 11's and 10's seem to benefit more with tube headers, but I am talking about the average MM performance owner. Facts are facts - look at the track times. You do not need tube headers and the high cost of the entire exhaust package to run good times with a SC. (NA do run better with tube headers, but I am talking about SC MM.) If you want good dyno numbers and impress the guys then the headers are great. But, its performance on the street or track that count. FRPP Cobra shorty headers and a Cobra hi-flow X-pipe into your stock mufflers and exhaust pipes for your SC do just fine especially if you are on a limited budget.

OK, let the :flamer:begin.


Glenn

He was at that time, the only N/A guy that gave me much trouble at the track. Some of my favorite races.

[Paul T. Casey]

Agreed. With my full exhaust done, I was running in the low 14's. After dyno tuning (and adjusting my A/F), I was in the mid 13's.

Sounds about right to me, if you're running the 4.10 gears. Do you remeber the drop from pre-exhaust to post-exhaust mod? Prior to re-tune I mean.

[red]

Sounds about right to me, if you're running the 4.10 gears. Do you remeber the drop from pre-exhaust to post-exhaust mod? Prior to re-tune I mean.
It was about .2 seconds.

[Paul T. Casey]

Wow, I did better with exhaust, but worse with tune. Kind of averaged out the same though.

[MarauderTJA]

Well here come the flames :flamer:.

Regardless of the dyno numbers the real track numbers do not strongly support tube headers on a SC as being absolutely necessary for good times. Look at the top 12 runners on the Timeslip page. Tube headers are not a requirement to run good SC times: two cars did not have tube headers - one was Lidio and one other guy.

Sorry fellows, but if you have a SC track times just do not support the high cost of tube headers and the custom X-pipe, etc. that people believe they should install as part of the "package". (I would not state this before due to my respect for a former Atlanta car shop owner.)

Yes, the extreme MM runners running low 11's and 10's seem to benefit more with tube headers, but I am talking about the average MM performance owner. Facts are facts - look at the track times. You do not need tube headers and the high cost of the entire exhaust package to run good times with a SC. (NA do run better with tube headers, but I am talking about SC MM.) If you want good dyno numbers and impress the guys then the headers are great. But, its performance on the street or track that count. FRPP Cobra shorty headers and a Cobra hi-flow X-pipe into your stock mufflers and exhaust pipes for your SC do just fine especially if you are on a limited budget.

OK, let the :flamer:begin.


Glenn

I agree Glenn. Early on when I had my P1SC on the stock motor, I had DR Cobra Exhaust system with high flow cats and an x-pipe. The car ran consistant 12.3's & 12.4's in the Florida heat. I really had to swtich over to long tubes after the built motor was put in an upgrading to the D1SC due to higher boost levels.