TURBODAWG

iTrader: (54)

I had an 03 Cobra with exhaust, x-pipe, air filter, and tune. Stock pully and ran a 12.24 @117 mph with it, on stock tires, 93 octane. My old Cobra would stomp me from a roll. The make from 360 to 380 whp stock. So I would think I would get beat pretty bad.

If you look as the curve from 5500 to 6900 RPM, you will see the torque curve is flat. That means as the HP will increase dramatically and linearly with RPM. Look at the power curve at the end of the pull, its almost 45 degrees. That is the strange part. The first part of the HP and torque curve looks in line with others, just the top end of the curve seems off, and I dont know why.

Just for some other info. 5zigen claims 45 whp from their exhaust. It uses a 60.5mm piping. This exhaust uses a 80mm piping and a straight thru, almost nothing to it muffler. All I know is I am the only one to dyno with this exhaust. I happen to have a filter, which WORKS claims something like 25 whp from their filter, and this one is foam and should flow better. Although HKS claims 11 whp from the filter. The boost controller is hold almost 18 psi at 7400 RPM. Which is about 3 to 4 more than stock, from what others have noted. So using the high end whp increases from all the parts installed would yield.

Exhaust 45 whp
Filter 25 whp
MBC (4 psi @ 10 whp per psi) = 40 psi

45+25+40 = 110 whp

So if I would have made 245 whp stock on this dyno (theoretical, because I didnt)

add 245 whp + 110 whp = 355 whp.

I am not saying this is correct, because I dont believe 5zigens numbers (even though they have graph versus stock vs just exhaust). I dont believe WORKS number however, I guess they have a graph to back it up, I havent seen it with my own eyes though. The boost controller, I did see with my own eyes how much boost it was holding, and 10 whp per psi increase is about right.

Once again, I am skeptical of my numbers but the graph somewhat makes sense if you look at the flat line of the torque up high. I am also skeptical of 5zigen, and Works in there hp increase also.

Brian

STi2EvoX

^You have to remember that part of what one part can add is dependant on another, and it's always a diminishing returns situation. For example, a tune (reflash) by itself will add 50hp on a X. An intake by itself might add 15 hp because of how rich the car is stock, but a filter and a tune together will not add 65 hp. The reason is that the main source of power from the filter is from leaning out the fuel mixture on a car that is too rich.

However, the main chunk of power from tuning the ecu is done from leaning out the car as well. Sure boost and timing and mivec are all aiding as well, but the point is that the filter isn't helping much after the car has been tuned. For instance, if you dropped in the filter after the car had already been tuned, you might only see around 2-3 hp. The exhaust on a highly tuned car making 700 horsepower will be contributing a huge percentage of that power because of how important getting the massive amount of exhaust gases out of the car is at that power level.

However, you can't take that huge number and apply it to a stock car and say that this is what the exhaust adds. Each part helps each other part and when all combined they represent different contributing percentages of the total sum, but can never be added together based on their individual contribution to a stock car. If this were the case then you'd have people making 500 hp with parts that everyone knows don't equal anywhere near that. Your car definitely needs a tune right now to smooth out that power band.

love9sick

Hahahaha 45whp from the exhaust

TURBODAWG

iTrader: (54)

I was wrong it was only 40 whp from the exhaust alone. Here is the graph taken from this thread:

Thread: https://www.evolutionm.net/forums/sh...d.php?t=330271


Graph: http://www.vividracing.com/catalog/w...5zevoxdyno.jpg


You are right, I need a tune, no doubt about it. I will get one once a good one is available. Not a fan of the ECUTEK. Waiting for a flash for the stock ROM.

Brian

STi2EvoX

^Ecutek adjusts the stock ecu ROM files. It is not a piggy back or a standalone, but as true of a reflash as any reflash software available. They have control over most all of the tables so far and will add anything that is needed later. Ecutek currently can adjust the mivec tables, all of the boost tables (wgdc, targets, gains, etc), ignition timing, air/fuel w/ idc mapping, etc... pretty much everything.

StevenStarke

iTrader: (77)

you do need a tune, but you cant add whp gains like that, it doesnt work that way.

-Steve

Robevo RS

iTrader: (16)

+1 on that

TURBODAWG

iTrader: (54)

You also dont pick up 25 whp from a drop in filter. All it does is have less restriction to flow. It cant change the air fuel ratio, because unless the pathway of the air is changed (turbulence for example or a non laminar flow) the MAF is not going to read any differently. With a cone filter the air flow pathway can and in some cases does change drastically. I was just making a point that whp increases claimed by others are equally ridiculous as my dyno number is. So if you can explain the 40 whp increase from that exhaust and the 25 whp increase from the filter, then there may be an explanation for my number. I do infact believe the dyno is a little optimistic for some reason. I wish I would have dynoed stock to see what it was and then had a before and after result.

Brian

evostang

What dyno was this in NC?