Dyno 4 weeks ago
no corrections or adjustments made to the dyno. Straight up 2000 lb load = 215 hp. Only mods to the 5AT was grounding and pop/z tube combo. Dynoed at 8:30 a.m. outside temp about 80 and humidity was high.
Today
Same set up on the same dyno. Same time of day and approximately same temp and humidity. Added the kinetix plenum and borla true dual.
Run one = loss of 2 hp! WTF!!!
Run two = gain of 1 hp! WTF!!!!!!!!!
Run three = same as first run! WTF!!!!!!!!!!!!!!!!!!!!!!!!!!!
Run four we try 4th gear. All previous runs were made in 3rd as any runs attempted in four would result in the speed limiter kicking in somewhere in the 145 area, again WTF!! Thought speed limiter was up in the 150's. So we run in fourth and get the same result 196 hp and stopped pulling at about the 145 mark. I'm so pissed and disappointed as I was in hopes of seeing at least 225. I figured a 10hp would have been a conservative but modest gain for the changes made but never did I expect 1 hp for $1000.00 in mods. Somethings up but where to start ? Compression test? 20 gauge it and put it out it's misery ?

 

did you get air to fuel readings?

i would get those done and then send your ecu to TS with those readings.

Daniel

03.5 5AT DP Coupe
Ground Kit / Z – Tube / Shock Sensor / 5% Tint - 30% Windshield
Clear Corners / L.E.D. Hood Lights / KPTech VDC Memory
KPTech OEM Remote Window Up / Invidia Exhaust

 

When you say "No corrections" ... do you mean physical or environment correction (ie. SAE)??? The latter is very important for comparison sake ... otherwise, the numbers are as good as nill.

Clint (THX723)

 

When did you add your mods? Doesn't it take awhile to actually reset the ECU? Obviously 4 weeks would be long enough but you didn't say at what point you added the plenum and exhaust.

2003 Blk/Blk Premium w/navigation
Tinted Windows (20%)
Chrome Wheels
BRM Catback Exhaust
Injen CAI (blue)
Unorthodox Crank Pulley (blue)
Clear Corners
Grounding Wires (blue)
255/45ZR17's rear

 

Man that's horrible I did a baseline dyno today before installing my UR Pulleys, 7 wire GK, Borla TD and XERD test pipe's and had good gains fromt he injen or just high stock HP and TW to begin with. Check out my dyno, my place also had to get the thing working and was similar conditions like you had. From after everything was installed, it feels like I gained like 50 hp and torque, no joke. My car pulls non stop now in any gear its sick. Sry to hear about your dyno man.. Reset your ECU and go back. here's mine


Martin
2003.5 BS G35
Nismo Aero/Sport Package
Injen CAI
B+G Springs
ADR M-Classic 19's..

309837-My G35 Baseline Dyno.jpg

 

there were no enviormental corrections made so that I would look at raw numbers, so to speak. I realize that with corrections it can make the numbers considerably different from what I got but for the sake of a true test ( using constants ) we made no adjustments to the dyno. As far as the length of time for the mods both upgrades ( ? ) were on the car for 600 miles and approximately 2.5 weeks. Should be enough time for the ECU to adjust. I'm concerned that there may be issues with the engine after all we've all seen the same mods done singley or as a combo and I don't recall anyone having similar results.

 

I dynoed last weekend four runs - there was about a 15 hp difference between the first two runs (which were ran back to back w/o really letting the car cool down after driving over an hour to the shop) and the last two runs (had the fan kicking on it for about 20 min between each run...

First run = 230.2
2nd run = 231.0

3rd run = 244.3
4th run = 244.9

All runs had a nice A/F Ratio that tailed down to ~12.5 at redline... I'm pleased, as the only reason I dynoed was to see what my A/F ratio was and to see if I need to send off for a reflash (even though it was good I still would like the reflash for the increased rev-limiter - my HP was still climbing @ redline! Torque started falling around 5800 rpms though)

2003.5 BS coupe 5AT
Clear Corners, Alum. Pedals, Pro-1 Intake, Helix Test Pipes, UR Pulley, Grounding Kit, CF Engine Cover, GReddy EVO II Exhaust, Kinetix Plenum

 

Did you get a chance to compare the entire graph, rather than just the "peak" numbers? Could be much different, then maybe they converge at peak.

In any case, my observation has been that the plenum combined with the cats result in a greater improvement than either individually. Maybe the exhaust just doesn't change much, other than the tone. Thanks for sharing your data. Try getting some 1/4 mile times, those might tell the tale more accurately provided you control for conditions.

2004.5 Coupe/5AT/Ivory/Everything but front spoiler/Nismo CAI/Crawford V5/Crawford Cats

 

Unfortunately, raw numbers aren't really good for anything. You could argue it's validity if you happened to have made the pre- and post-mod runs back to back within the hour ... even then, corrections factors would greatly improve accuracy. Temperature is only one variable with barometric pressure and humidity being the two other major ones factored into the correction. SAE correction was enough to attribute 8hp (or 3%) in my case.

Other suspect is the Kinetix Plenum. I have recently made the addition myself (v4). After a few weeks and 1500 miles later (in the sizzling California summer heat), I find all the bolts (including those holding the throttle body) have loosened, cause virtually undetectable leaks all around. This explains why the car felt a bit ‘flat’ the past week, which I shrugged off as the doing of the summer heat. The bolts were torqued down properly w. loctite applied initially.

You might want to check the bolts. Set torque wrench for 5 in-lbs (slightly under spec) and see if any of them budges. If so, back them out completely and re-apply loctite then retorque to spec (6 in-lbs). Let cure for two hours or so before starting engine. Looking at the bolts I backed out ... it appeared little loctite actually made it to the lower plenum threads. It was getting caught up by the cork gasket as the bolt is inserted through it. For a piece of mind, I took the plenum off and trimmed off the excess cork material around the bolt holes. All seems ok and strong once again.

Hope that helps. Good luck!


Clint (THX723)