Rock

Hi Fellas,

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.

DFW01E55

I think that a comparison of the weather conditions between each trip to the track might yield some interesting results. It may be that 4mph in trap speed is an accurate indication of weather impact.

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.

zapco98

It is always possible that it does not work as good as the stock box. If you said it was 85-90F out, I might consider attributing it to heat - but the car should run great in the 60s, and 4MPH is a loss of ~40-45HP...

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.

ChicagoX

Do you have the slips handy?

I would like to compare the back half of the runs to see if the car is laying down for some reason.

Rock

Here ya go:

Yacht Master

Rock, FWIW time to look at your IATs are you still on stock I/C pump?
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.

Rock

I'm not discounting the air box yet (Victor knows where I live).

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.

vader

I can't imagine their is less flow thru this box than the stock setup.

ChicagoX

Your 330' and 1/8 mi are a little off, but you really can't complain about gaining 26mph on the back half of the strip. That's on target for an 11.1-11.2 or so.

I would check IAT's to see if timing is being pulled.

juicee63

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!

chiromikey

i would really like to know the da behind each run. here's a couple of websites that will help you get those numbers:

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.

juicee63

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!

vader

Chiro...one of Rocks previous runs was K2+ Vrus TB- 12.0 @ 124.6

Isn't that a 10 sec ond mph ???? Jeez that is flying downtrack.

chiromikey

i'll try to do the da corrections later...moto gp is starting right now!!!

chiromikey

for THESE cars, his mph probably should correspond to a very low 11 second DEPENDING on what he did on the first half of the track. with a 1.6x 60ft and that mph...look the **** out!!!

stevebez

Hmmmm.... well a few things come to mind...

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.

jparch

Hmmm.... maybe you need the python air tubes..

Rock

Mikey, I'm not sure that the weather conditions had much to do with the results. I have had trap speeds of 122+ in 70-80 degree weather when I was K2 only.

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.

rflow306

+1. Especially with no track results of his own.

AMG_55

1st off- you have a vary fast ****in car

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

Jrocket

I dont remember off hand,but are the intake ducts bigger or do you use the stock sizeing tubes still? If the tubes are infact stock size still,then how does a larger air box do any good,you still have to pull air through a restricted intake tube correct?If they are indeed alrger,then how does it get passed the narrow opening on the drivers side front panel.mean while Im going to search through the air box thread for answers.

bleek

Rock, when you have a chance to do the ecu reset. If the ecu is having a problem, reset it and let it adapt and you should be fine. But it shouldn't have a problem, as the ecu from what i know of Kleemann tunes don't need reseting to see results. I've bolted up a bigger TB with a Kleemann tune and saw immediate results. Also like someone else said just do a quick swap back to the old set up and take her for a pass. When are you going to the track again, bring both set ups with you. Proper cool down would help, but i doubt your johnson pump is crapping out.

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!

chiromikey

do you have your previous time slips so that we can compare the data for the entire run instead of just the final results? there still may not be enough info to know what's happening but the educated guesses will be better than the mass speculation that's going on now.

rflow306

He said no problem, I just need a definite date to set-it up. So far it's my car and PTE's car if everything works out. I am always down for some heads-up racing.

Rock

Jrocket, the intake tubes are the same size.

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.