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.

 

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.

 

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.

 

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 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.

 

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...

 

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.

 

kayman,

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.

 

heavychevy,

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.

 

PM sent.

 

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

 

well I never bought the evom headers. But I did get another aftermarket set for only a few hundred bucks. No power gains, but it did reduce lag and improve exhaust sound a bit. I'm happy with my setup.. but it does bug me when I see misleading claims.

 

Given the same turbines the faster spool will always occur in the car with less backpressure. Exhaust backpressure of any amount gives some resistance to the turbine wheel spinning.

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.

Absolutely. Most of the Fabspeed and eBay headers are using cheap thinwall Chinese SS. The welds are nice, the collectors passable, but the thinwalls will not hold heat the way the factory units will. You need a good gauge 321SS (or even inconel ideally). If you go with the cheapo units I would thermal coat them and forgoe the bling/polish.

 

sigh...i drank that coolaid...

 

I like the idea of being charged for what goes into your car rather than being charged for how much horsepower you end up with.

 

If Scotts car still runs 10.6 with more or same mods after 50k more miles I'll be a beleiver, but there are WAY too many fly by night rememdies for power that dont address all of the needs of the motor. Fact of the matter is that most of us are shortening the lives of our motors, but by how much and how exponentially is the question. Some of these mods simply releieve stress on other parts of the motor, I know some of us are just as concerned with longevity, especially the way we drive our cars, at least I am.


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.