shil01

Well I got my car dyno'ed yesterday.
About a month ago I baselined at 234HP. Same day I added test pipes and redyno'ed to 238.9. Not to shabby. Almost 5 HP increase (expected)
Anywhoo, ive been a busy beaver and have since installed Crawfords Plenum, Injen CAI, Borla Headers, and Borla TD CatBack Exhaust. All installed within the last 2 weeks.
I wanted to redyno between all mods but alas I was impatient, and had most of my mods installed within days of each other and did not have a dyno readily accessible.
So I finally got my car redynoed yesterday and these were the results.
Pic is a bit confusing and shows all my dynos done since ive bought the car. Made 2 pulls yesterday -Blue and Red are yesterday's dyno with all my mods. Green is with the test pipes and purple is baseline.


Thats a peak of 248HP from 234. Thats a total increase of 14 HP! I was expecting close to 265HP+ with what I have done but was sadly mistaken. Thats approx $215 per HP!
All runs were said to be done in 5th. (I'm wishfully thinking the last ones were run in 6th.
I definetly felt an increase after the plenum and Borla TD from the butt dyno, but dynos prove an insignificant gain after all were installed.
Could i have had something installed incorrectly?

FLY BY Z

What were the temp and humidity on the different days? If the conditions on your first dyno were perfect and the last one was in less than ideal conditions it could have very easily chopped off some HP.

dwnshift

iTrader: (1)

To me that looks about right with those modifications from what we have seen on our race car.

Import-Tooner

I wonder what a a/f controller would do. If you had a way to do some fine tuning I bet you could tap into the 260+ numbers.

Dissolved

ouch

KONVERTER

iTrader: (2)

did you drive your car like grandma during the break in period>?

zzzya

iTrader: (2)

Did you have a fan in front of the car blowing air into the CAI? With all of the back-end exhaust mods you have done, you really could use some good airflow coming in on the front end. The CAI may be hindering your numbers if there was no fan.

shil01

Potato head- all dyno runs were done between 76-78 degrees
Pure- theirs my buddy! btw- i see you have a knack for making friends on this board (BOING!)
Konverter- I did drive like a grandma, some say good, some say bad.

Ok. I think I have found something very conspicuous.
Maybe good news!
I have attached below some more info on runs 2 and 4
Run 2 was done with the test pipes and run 4 was with the whole setup.



Note the Gear ratio for both runs. My first set of runs (dynorun2) shows 59.74 RPM/MPH. The second set of runs (dynorun4) 46.74 RPM/MPH. (This is also reflected the same on dynoruns 1 and 3 respectively)
Also the difference between time it took to get to 6000RPM's. On the first set of runs it took 7.34 sec. On the second set of runs it took 11.94sec.
Can anyone analyze this that has some dyno experience?
To me it looks like these runs were run in different gears.
Can anyone confirm?

KONVERTER

iTrader: (2)

you did your dyno run in 3rd gear???

shouldnt it be done in 5th????

shil01

No. I specifically told the dyno tech both times (to his surprise) that the 1:1 gear was 5th and he told me both times it was done in 5th. Why do you think it might have been 3rd?

SpoonieLuv

Wow. I've seen a few stock Zs dyno 245-250hp at the last event. Some guy did a little over 250hp on this board stock

damen

did you flash your ecu or is that not needed?

FLY BY Z

Just calculate what gear matches what MPH.

Run 2 equals 6000 RPMs and you would be doing 100 MPH.

Run 4 equals 6000 RPMs and you would be doing 128 MPH.

So whatever gears matches those speeds is what gears you were in but obviously you were in different gears for those two runs.

Run 4 had you in a higher gear than run 2.

KONVERTER

iTrader: (2)

because you have 75mph.

since you drove like grandma i think your car isnt opening up like it should

hfm

iTrader: (1)

Damn. That's depressing.

350Z_Redline

iTrader: (1)

If the car was running too lean would it get lower numbers? I have a setup similar to shil01's minus the plenum. I was told that the addition of the plenum to my setup might have the car run too lean. Did you get your A/F ratio taken during the dyno?

VandyZ

iTrader: (2)

IMO, you will see little increase in HP from either Borla headers or Injen CAI. Also you are putting too much emphasis on the "peak" number. Look at the entire graph. It looks real good to me and you only have 3300 miles. Your engine is only a little over the half way mark for being totally broke in. Re-dyno at 5000 and you may see a couple more, especially if you kept it under 5K rpm for the first 1200.

Some points:

you gained 10 at peak between the current and last session. With the plenum we have seen a range of 7-11 hp gain at peak. You are right there with the best of them, maybe the other mods helped you get there. Look at your curve after 5500 that is a huge gap . . . very nice! Both tq and hp curves are impressive. Don’t give up yet. Next time do the runs with the A/F ratio gauge and track that as well, you may need a little more fuel like someone else said. Also, you are running a very free flow system with much less back pressure than stock setup

shil01

Can anyone tell what gear the car actually was in by the data provided? The more I look at it the more apparent it seems that both runs were at different gears. 5th and then 6th, or 4th and then 5th. I am going to call the shop today to see if I can redyno but I need some info to argue my case.

i did run with A/F ratio. it went from 14 to 13.2 as the car went up in revs (on the modded runs). My baseline ran a bit richer @ 13.6 to 12.6.

Some of you guys also reference what speed I was going. 75MPH or 100 MPH. I dont see anywhere referencing speed except for the gear ratio, and I don’t think that is the actual speed I was going but rather RPM's per MPH ratio. I’m thinking out loud here but if the gear ratio states 59.74 RPM's per 1 MPH (is that a correct assumption) then that would put my car at 108MPH at 6500RPM's and that would be the top of 4th. If the gear ratio states 46.76 RPM's per MPH then that would put my car at 139MPH at 6500RPM's and I think that is the top of 5th. Is this a correct assumption? (or maybe I dont know WTF im talking about!) I think this is on the same lines as what Mr. Potato was saying.
Someone please confirm and if there are any dyno techs or others with this data sheet to compare please reply.

Thanks guys
-Richard

VandyZ

iTrader: (2)

Dont get too worked up about it, we did comparison between 4th and 5th gear pulls and it only showed around 1 (+/- .5) hp in favor of 4th gear. But it does look like run 4 was in a higher gear than 2. Which is good if you think that run 2 may be biased higher because of using a lower gear. I think you are correct in your thoughts. We run our own cars at the dyno here and they hated that we had to take the car that fast in out 1:1 gear.

LeighJr

iTrader: (1)

Overall I think 14+ rwhp is respectable a little expensive but still good, and dynos Lie everyone is different, Go find that Mossy Dyno!! it will give you the #'s you want.