VRUS airbox track results (inside).
Well, I finally got back to the track last night to see what my latest modification would do for my car. For those that don't know, I have gone to the track after every modification to verify the addition adds power. Below are some of the better track #'s after each augmentation:
Bone stock- 12.6 @ 114
K2- 11.9 @ 122.3 but initially after the K2 mod, I ran a 12.2 @ 119
K2+ Vrus TB- 12.0 @ 124.6
When I look at a modification to determine if it increased HP, my focus is more an trap speed than et. I have run with both DR and PS2 rubber and in my hands I get similar results. I also understand engine temps and outside temps will affect your trap speeds. Furthermore, some people believe that the ECU must adapt to your latest mods to get maximum power.
So, I'm not sure how to interpret my results last night running K2+Vrus TB+ Vrus airbox. The numbers............... 11.7 @ 120.2 (temps were in the mid to low 60s, PS2 rubber).
Any thoughts? The only things that I did different................ I ran as soon as I got to the track (45min away) and no prerun ice packs to cool intake temps.
There is a highway ramp where I hammer the car on whenever possible, the difference is 10mph from winter temps to summer temps, 143 winter to 133 summer. It's obviously longer than a 1/4 mile but the temperature/speed ratio might hold.
Nice time though, it would be nice to see what DR's and cold air would give you.
Well, I finally got back to the track last night to see what my latest modification would do for my car. For those that don't know, I have gone to the track after every modification to verify the addition adds power. Below are some of the better track #'s after each augmentation:
Bone stock- 12.6 @ 114
K2- 11.9 @ 122.3 but initially after the K2 mod, I ran a 12.2 @ 119
K2+ Vrus TB- 12.0 @ 124.6
When I look at a modification to determine if it increased HP, my focus is more an trap speed than et. I have run with both DR and PS2 rubber and in my hands I get similar results. I also understand engine temps and outside temps will affect your trap speeds. Furthermore, some people believe that the ECU must adapt to your latest mods to get maximum power.
So, I'm not sure how to interpret my results last night running K2+Vrus TB+ Vrus airbox. The numbers............... 11.7 @ 120.2 (temps were in the mid to low 60s, PS2 rubber).
Any thoughts? The only things that I did different................ I ran as soon as I got to the track (45min away) and no prerun ice packs to cool intake temps.
In my S4, I would never see a 4mph drop even with heat soak(want to talk about a hot engine bay). A couple tenths of a second and 1-3mph at max(1-2 on avg). On the flip side, I have never been one to sit there "preparing" my car with ice, because its not what it will ever do on the street.
Not knowing anything about this airbox, were the proper pressure drop measurements taken in car, under load? You can destroy a cars performance with an incorrectly built/tuned airbox.
Last edited by zapco98; May 6, 2007 at 10:24 AM.
I think the first ECU reaction to high IATs is to pull timing.
ETs show that you can drive, I would not discount the air box just yet.
The highway drive to track with no cool down, that hurts. One last thought did you reset your ECU? Last thought, sometimes I think our ECU suffer from mild retardation or maybe it is just ADD, some resets work better than others.
I have the Johnson pump that Kleemann installed.
No, I did not do the "sneaky reset"..................... and yeah, maybe my intake temps affected the run.
Trending Topics
The Best of Mercedes & AMG
That's on target for an 11.1-11.2 or so.I would check IAT's to see if timing is being pulled.
Man , that is impressive. Sorry I cannot comment on your Mods or offer any insight. I am just amazed at the trap speed. I think you will be down in the low 11s on a cooler night. Your ECU likely needs time to adjust to the new air flow and power. Id try reseting it. Course I know how to do that LOL. Great run ROCK!
http://www.modulardepot.com/density2.php
http://wahiduddin.net/calc/calc_da.htm
weatherunderground.com can even help you retrieve the weather conditions for past runs so that you can make those calculations.
keep in mind that you're NOT losing 4mph. often when you lower 1st half track times or et's by a couple of tenths, you can also lower mph. a comparison of the intermediate times/mph for all the runs would be more helpful in considering what's actually going on.
you can test this theory. launch softer off the line and you'll likely add 1-2mph to your traps speed. this is why people typically never get their best et on the same slip as you best mph.
http://www.modulardepot.com/density2.php
http://wahiduddin.net/calc/calc_da.htm
weatherunderground.com can even help you retrieve the weather conditions for past runs so that you can make those calculations.
keep in mind that you're NOT losing 4mph. often when you lower 1st half track times or et's by a couple of tenths, you can also lower mph. a comparison of the intermediate times/mph for all the runs would be more helpful in considering what's actually going on.
you can test this theory. launch softer off the line and you'll likely add 1-2mph to your traps speed. this is why people typically never get their best et on the same slip as you best mph.
Ok Chiromikey, THANKS for the info , I just did the calculations .. If my car ran a 13.14,Density Altitude = 3595 feet. Where would the car be with a lower DA? My traps were 104-111 and times mostly in the mid 13's. THANKS, LOL, says the wind was ONLY 62 MPH!!!!
You guys ROCK , no pun intended. Once again I feel like a little hijacker!
You guys ROCK , no pun intended. Once again I feel like a little hijacker!





1. The VRAB might not be the bottleneck in your airflow... and while better than stock is not helping the overall efficiency.
2. Your ECU may need to be remapped to cater with the extra airflow.
3. Your pump is on its way out.
4. Heat soak ...
5. Tranny was in "cruise mode" and not "grip it an rip it" mode... after the long drive.
I cannot see how the VRAB would affect your ET's negatively in anyway... in every respect the flow is BETTER ... but maybe the package not coming together properly (back to ECU again).
I guess only way to be sure is a re/re of the airbox at the strip in back to back runs ... in same conditions, prep, launch etc. This should not take too long.
Stevebez, you bring up a number of possible explanations and I'm thinking either "my ECU may need to be remapped to cater with the extra airflow or the tranny was in "cruise mode" and not "grip it an rip it" mode... after the long drive."
jparch, if you have a gripe with Victor and his products, why don't you just specifically tell us what they are................please enlighten us. I have noticed that this is not the first time you have dismissed his efforts with a glib remark.
Last edited by rflow306; May 6, 2007 at 10:38 PM.
i think what maybe happening, as some said, is that ecu is trippin out; the stock air boxes are very restrictive and vrus' box looks like it is MUCH more efficient and has better flow characteristics, the increase in flow might be too much for the stock ecu to comprehend
i would try to find a place to do a custom dyno tune
Go through a process of elimination, swap out filters and such, should be fine, oh yeah i still want ten cars!
Rflow, did you find out if you can borrow your buddies two-car trailer? Bring your ***, i got the steaks, but you better becareful with our Canadian beer! Hey Rflow how about you and jparch knock it out when you get here, should be a good race, then you'll have a chance to see his track results, if your interested drop me a pm and we can set something up, but no Canadian beer for you until after!

Bleek, thanks for the recommendations, I will give them a try.
Mikey, I'll have to do some digging but I think I still have a number of them. I need a little time to get that info together.
On a side note, the CEL came on yesterday, one day after running at the track. I'm taking it in on Thursday for some diagnostics.




