View Poll Results: What is the best option for my driving goals.
Buy Package Headers (i.e. evo etc.)
6
16.22%
Buy Custom Headers
2
5.41%
Port Stock Headers
21
56.76%
Leave Them Alone.
8
21.62%
Voters: 37. You may not vote on this poll
Headers....Again!!!!
#31
Originally Posted by eclou
In regards to headers on the 99x setup - the key to spooling up is pressure drop and velocity. Less back pressure behind the turbine will allow the wheel to spool faster. Open exhaust cannot be beaten for creating the biggest pressure differential across the turbine. However, if the turbo spools so quickly that the motor cannot increase the fuel trim to match, it is possible the AFR is becoming too lean and less than optimal power is being produced.
Now as far as velocity, the hotter the gasses, the higher velocity. If you run headers whose primary tubing is too large, too long, or allows more radiation of heat (stock manifolds are double walled) then the velocity will diminish and the turbine will not spool as quickly. I think a safe header will use the same size dia tubing as stock, be equal length, use an efficient merge collector (NASCAR style, Burns, etc) and have a thermal coating to keep the heat in.
Now as far as velocity, the hotter the gasses, the higher velocity. If you run headers whose primary tubing is too large, too long, or allows more radiation of heat (stock manifolds are double walled) then the velocity will diminish and the turbine will not spool as quickly. I think a safe header will use the same size dia tubing as stock, be equal length, use an efficient merge collector (NASCAR style, Burns, etc) and have a thermal coating to keep the heat in.
#32
Originally Posted by kayman
of course I don't believe their claims. I just find it really funny they are able to get away with it. Never said I bought into thier marketing hype.
btw, here's a direct quote from their website:
"Power gains are increased by 17 HP and 20 Ft. TQ with no other modifications." thats listed in the descripton for the k24 headers.
If I were to buy both their stage 3 kit and stage 4 kit, the only difference in the package would be the inclusion of the headers in the stage 4. Yet they state that difference in hp gained between these two bolt-on kits is 50hp. So essentially what they are claiming is that without any other mods, the headers give you 17hp. And if you add them along with an exhaust, intake, flash and k24s, you'll somehow manage to get 50hp.
Yet based on everything I've read on the forums, nobody has felt or measured any power gains from headers alone. Has anyone called evoms out on this?
btw, here's a direct quote from their website:
"Power gains are increased by 17 HP and 20 Ft. TQ with no other modifications." thats listed in the descripton for the k24 headers.
If I were to buy both their stage 3 kit and stage 4 kit, the only difference in the package would be the inclusion of the headers in the stage 4. Yet they state that difference in hp gained between these two bolt-on kits is 50hp. So essentially what they are claiming is that without any other mods, the headers give you 17hp. And if you add them along with an exhaust, intake, flash and k24s, you'll somehow manage to get 50hp.
Yet based on everything I've read on the forums, nobody has felt or measured any power gains from headers alone. Has anyone called evoms out on this?
#33
Originally Posted by jimmer23
Dude, don't you get it? He said they're not going to list or tell you in their marketing all the differences between stages X and Y. No math in the world will reconcile the numbers because YOU DON'T KNOW ALL THE FACTS. Why would any tuner do this - so you can price compare and nickel-and-dime them out of their profits? R&D goes into these stages for a reason, and I think it's pretty well known that the shops are only going to tell you the obvious (visual) differences between the kits.
and this still doesnt address the fact that they claim the headers add 17hp without any other mods.
#34
Originally Posted by kayman
I dont think you get it. They sell these "stages" as off the shelf bolt-on kits. There's nothing they can hide, when all the parts are shipped to the customer directly. If I purchase the kit online, evoms doesnt do the installation. How can they conceal anything when I have all the parts right in front of me? When I talked to evoms, I told them I have their stage 3 setup and aksed what I would need to go to thier stage 4. I spoke with mike and he confirmed all I needed was the headers and that there is no difference in the software and a reflash is not part of the upgrade. Plus I was told that their stage 3/4 sotware is the standard GIAC k24 file anyway.
and this still doesnt address the fact that they claim the headers add 17hp without any other mods.
and this still doesnt address the fact that they claim the headers add 17hp without any other mods.
I did header alone tests years ago. I stated earlier that by simply replacing stock headers with custom headers (in my case S Car Go headers) the motor would go lean. To get the extra power or the A/R's out of the lean range we had to add fuel. Remember, only added fuel makes power. I'm sure this is simular to what EVOMS is doing.
I find their claim of 17 hp very credible. It is in line with our own tests. But ......... they had to add fuel to get there. Another way of putting it, if your motor was tuned correctly with stock headers and you simply added a good set of tube headers you probably lost power with adding fuel and changing the tune.
Last edited by cjv; 08-04-2007 at 01:34 PM.
#35
Originally Posted by cjv
kayman,
I did header alone tests years ago. I stated earlier that by simply replacing stock headers with custom headers (in my case S Car Go headers) the motor would go lean. To get the extra power or the A/R's out of the lean range we had to add fuel. Remember, only added fuel makes power. I'm sure this is simular to what EVOMS is doing.
I fine their claim of 17 hp very credible. It is in line with our own tests. But ......... they had to add fuel to get there.
I did header alone tests years ago. I stated earlier that by simply replacing stock headers with custom headers (in my case S Car Go headers) the motor would go lean. To get the extra power or the A/R's out of the lean range we had to add fuel. Remember, only added fuel makes power. I'm sure this is simular to what EVOMS is doing.
I fine their claim of 17 hp very credible. It is in line with our own tests. But ......... they had to add fuel to get there.
Last edited by kayman; 08-04-2007 at 01:37 PM.
#36
Originally Posted by 9Eleven
Bro, throttle response and lag are due to exit gas, not intake. As long as the turbos have less backpressure they will spool up faster and the trottle response will increase. The air going in is plenty for a k16 or 24. The stock headers are more than capable of delivering enough air to the turbos. When I was looking at the whole set up the other night when I installed my exhuast it was pretty obvious to me and to my tuner. But as I wrote earlier, if you go bigger turbos, now you're talking a lot of changes.
With that being said how can you say the intake is more than sufficient? What are you using to make this assessment? There is still a motor there, there is not just turbos, and those turbos feed off of the motor so there will be some difference with an intake, but how much is what I'm trying to find out, and I'd like info from someone who has studied this (on a car) or done the mod themselves.
#37
Originally Posted by kayman
that makes sense. its just odd that more fuel is not part of their stage 3/4 kits yet they still make the hp claims. and I bet many people have purchased their headers after reading "17hp with no other mods" only to realize no gains. oh well, I guess that's buisness...
Expect the misleading when it comes to protecting a so called trade secret. This applies to everyone in the business. After all it is the way they make their living. You can't really be mad at them. Just remember, because of the profits involved with the 996tt, advances have been made power wise and the prices have continued to come down year after year. I can remember when 15K would get you about a 480 hp motor.
#38
Originally Posted by heavychevy
I think you are confusing the two, throttle response and lag are NOT the same thing, even in a turbo car. Throttle response is directly related to how much air the motor can inhale upon pressing the gas, and then how fast the air is able to escape through the exhaust, it it not a one way street what so ever, a motor that cant breath wont respond.
With that being said how can you say the intake is more than sufficient? What are you using to make this assessment? There is still a motor there, there is not just turbos, and those turbos feed off of the motor so there will be some difference with an intake, but how much is what I'm trying to find out, and I'd like info from someone who has studied this (on a car) or done the mod themselves.
With that being said how can you say the intake is more than sufficient? What are you using to make this assessment? There is still a motor there, there is not just turbos, and those turbos feed off of the motor so there will be some difference with an intake, but how much is what I'm trying to find out, and I'd like info from someone who has studied this (on a car) or done the mod themselves.
Throttle response has alot to do with the AR or your turbo (there is basicly three ratio's) and torque of your motor. Years ago Ruff motors had better response simply because they enlarged the restrictive tubing from the MAF to the turbo. This really made a difference in torque believe it or not. I could go on .............. but I won't for now.
#39
Originally Posted by heavychevy
I think you are confusing the two, throttle response and lag are NOT the same thing, even in a turbo car. Throttle response is directly related to how much air the motor can inhale upon pressing the gas, and then how fast the air is able to escape through the exhaust, it it not a one way street what so ever, a motor that cant breath wont respond.
With that being said how can you say the intake is more than sufficient? What are you using to make this assessment? There is still a motor there, there is not just turbos, and those turbos feed off of the motor so there will be some difference with an intake, but how much is what I'm trying to find out, and I'd like info from someone who has studied this (on a car) or done the mod themselves.
With that being said how can you say the intake is more than sufficient? What are you using to make this assessment? There is still a motor there, there is not just turbos, and those turbos feed off of the motor so there will be some difference with an intake, but how much is what I'm trying to find out, and I'd like info from someone who has studied this (on a car) or done the mod themselves.
#40
Originally Posted by kayman
that makes sense. its just odd that more fuel is not part of their stage 3/4 kits yet they still make the hp claims. and I bet many people have purchased their headers after reading "17hp with no other mods" only to realize no gains. oh well, I guess that's buisness...
Why is it that Protomotive does not sell headers with the 700 HP kit... they prefer stock.
Things that make you go hhmmmm.... Scott ran a 10.6 on stock internals with STOCK headers.... Someone please explain to me why you need $2K headers for a 480 rwhp car?
Kayman, now that you have your stage 3/4? not sure... you should get together with Awais(BTW, he has stock dvs, headers, and even air filter)... and you will see what I was trying to tell you.
Problem with all of us, and I am guilty in the past of this, is that we all like to believe our cars are 600HP, 650hp, 700hp cars, etc.... so we buy into the marketing trickery.... and spend $6K on turbos, 2K on headers, 5K on exhuast, etc.... I think that is crazy.
I can get stock K16s converted to K16/24s for $1000 a pair.
If I knew back then what I know now... I would have saved $40K.
markski
__________________
2001 996TT 3.6L and stock ECU
9.66 seconds @ 147.76 mph 1/4 mile click to view
160 mph @ 9.77 seconds in 1/4 mile click to view
50% OFF ON PORSCHE ECU TUNING BLACK FRIDAY SPECIAL
2001 996TT 3.6L and stock ECU
9.66 seconds @ 147.76 mph 1/4 mile click to view
160 mph @ 9.77 seconds in 1/4 mile click to view
50% OFF ON PORSCHE ECU TUNING BLACK FRIDAY SPECIAL
Last edited by markski@markskituning; 08-04-2007 at 02:24 PM.
#41
Originally Posted by MARKSKI
Remeber I spoke to you a few times.... you should have listened...
#42
Originally Posted by jimmer23
FYI - Less backpressure (i.e. high flowing exhaust) creates more lag but more top-end HP. More backpressure will spool quicker with less peak HP.
I think you are confusing exhaust systems in naturally aspirated motors vs FI - in N/A motors resonance tuning has been shown to be very helpful in exhaust scavenging from the ports of the head. You can tune the optimal scavenging for different rpm ranges depending on the intended usage of the motor. In an FI system the scavenging is far less effect on HP gains than just reduction of backpressure.
Originally Posted by cjv
Your omitted three items. Thickness of tubing. Thicker tubing retains more heat than thinner tubing. Type of material. Some materials retain heat better that others. And sound wave distortion to valves. There should be a slight lip at the upper edge where the head/header meet to prevent this distortion from traveling back to the valves. People make a big mistake when they simply gasket match.
#43
Originally Posted by MARKSKI
Remember I spoke to you a few times.... you should have listened...
Why is it that Protomotive does not sell headers with the 700 HP kit... they prefer stock.
Things that make you go hhmmmm.... Scott ran a 10.6 on stock internals with STOCK headers.... Someone please explain to me why you need $2K headers for a 480 rwhp car?
Kayman, now that you have your stage 3/4? not sure... you should get together with Awais(BTW, he has stock dvs, headers, and even air filter)... and you will see what I was trying to tell you.
Problem with all of us, and I am guilty in the past of this, is that we all like to believe our cars are 600HP, 650hp, 700hp cars, etc.... so we buy into the marketing trickery.... and spend $6K on turbos, 2K on headers, 5K on exhuast, etc.... I think that is crazy.
I can get stock K16s converted to K16/24s for $1000 a pair.
If I knew back then what I know now... I would have saved $40K.
markski
Why is it that Protomotive does not sell headers with the 700 HP kit... they prefer stock.
Things that make you go hhmmmm.... Scott ran a 10.6 on stock internals with STOCK headers.... Someone please explain to me why you need $2K headers for a 480 rwhp car?
Kayman, now that you have your stage 3/4? not sure... you should get together with Awais(BTW, he has stock dvs, headers, and even air filter)... and you will see what I was trying to tell you.
Problem with all of us, and I am guilty in the past of this, is that we all like to believe our cars are 600HP, 650hp, 700hp cars, etc.... so we buy into the marketing trickery.... and spend $6K on turbos, 2K on headers, 5K on exhuast, etc.... I think that is crazy.
I can get stock K16s converted to K16/24s for $1000 a pair.
If I knew back then what I know now... I would have saved $40K.
markski
#45
Originally Posted by MARKSKI
Remember I spoke to you a few times.... you should have listened...
Why is it that Protomotive does not sell headers with the 700 HP kit... they prefer stock.
Things that make you go hhmmmm.... Scott ran a 10.6 on stock internals with STOCK headers.... Someone please explain to me why you need $2K headers for a 480 rwhp car?
Kayman, now that you have your stage 3/4? not sure... you should get together with Awais(BTW, he has stock dvs, headers, and even air filter)... and you will see what I was trying to tell you.
Problem with all of us, and I am guilty in the past of this, is that we all like to believe our cars are 600HP, 650hp, 700hp cars, etc.... so we buy into the marketing trickery.... and spend $6K on turbos, 2K on headers, 5K on exhuast, etc.... I think that is crazy.
I can get stock K16s converted to K16/24s for $1000 a pair.
If I knew back then what I know now... I would have saved $40K.
markski
Why is it that Protomotive does not sell headers with the 700 HP kit... they prefer stock.
Things that make you go hhmmmm.... Scott ran a 10.6 on stock internals with STOCK headers.... Someone please explain to me why you need $2K headers for a 480 rwhp car?
Kayman, now that you have your stage 3/4? not sure... you should get together with Awais(BTW, he has stock dvs, headers, and even air filter)... and you will see what I was trying to tell you.
Problem with all of us, and I am guilty in the past of this, is that we all like to believe our cars are 600HP, 650hp, 700hp cars, etc.... so we buy into the marketing trickery.... and spend $6K on turbos, 2K on headers, 5K on exhuast, etc.... I think that is crazy.
I can get stock K16s converted to K16/24s for $1000 a pair.
If I knew back then what I know now... I would have saved $40K.
markski
Are there any examples of these same packages with 70 80 100k miles on them that havent blown something, I know the turbo motors are die hard but with the beating my motor takes at the road course, I would like to KNOW my mods are safe.