Re: Tale of Three Dyno's
Well, now I’m at BBR with my SRT on the dyno and the first two pulls sound like my granny was behind the wheel. Slow acceleration never hitting the limiter – producing very disappointing numbers. But it seems revenge is always mine – on run #2 my oil dip stick came loose and my SRT shot oil all over the shop.. Also my AFR readings were all over the place. Well, I was told that the 185mm pulley was making way to much boost and causing me to run lean and thus not making HP - - etc etc… But then after some clean up time at the shop- and when it was just me and the owner (and a few kids looking to fill their nitrous bottles) I asked him to hit the rev-limiter on Run #3. It was still a dog pull but here are the results followed by the AFR charts.
Notice how low the torque curve is compared to the other dyno charts – notice the top of the charts says “Dyno Comparison?”
Bottle_Blown_Blowup-1.jpg
Bottle_Blown_Blowup_AFR-1.jpg
The good part about this run is that I reached 361.7 Peak WHP - very close to what the website that translated my DynoDynmics (308.1) numbers to DynoJet said…
But wait – my SRT is sitting on at SuperFlow dyno… Turns out I saw them looking at other charts after run #2 (there was a remote monitor) - and I saw some sort of conversion with my dyno my chart while comparing it to some other runs.
I don't know why BBR could never get my SRT6 into the Dyno mode. My ECU is setup to run to 6,150 RPM and the BAS and ESP light should illuminate. (A special feature of the SI tune – no external settings required and no fuses to pull to get into the Dyno Mode – just strap up and go)
At the end of run #3 I asked what was up with the different charts (Dyno Comparison)? Turns out this system will convert the SuperFlow data charts into DynoJet charts. I wonder now If I hadn’t asked him to hit the rev limiter or had seen this conversion feature, just what my peak HP and Torque # print charts would have looked like compared to …… – well, I think you know.
Take a look at the other charts posted on the forum from this shop – look how similar the curves are to my other charts – notice they are all labeled “Dyno Comparison"…
Now look again at the AFR chart – what had happened to my SRT6? - Turns out nothing, but I was concerned enough that I called Andy at the Corvette shop today and asked if he remembered me (it’s been a year) and my SRT6 – he did – I gave him the run down and he said bring the SRT over and let’s put her on the dyno. When I got there he was finishing up with a customer (08 Vette) over $6K in mods, an old farmer boy (I would guess about 70) from the central valley whips out a wad of $100 bills – Anyway – Andy looked at the charts and then looked at my tail pipe and remembered why he had not done a AFR last time (See Dyno chart #1). Turns out his sniffer is custom made for Corvettes and the probe wouldn’t t fit right in my pipe. He says he can disconnect the O2 sensor from the probe and clamp it on the very end of one of the exhaust tips and just sniff one side. He said it would read a leaner then a normal probe but it would at least give me a Idea and a second opinion.
So here is the Dyno Chart from that run – everything back to normal with the AFR rock steady at 13.5 (with a proper probe up the exhaust pipe I would say 12.5 – 12.8) - so based on this and my DynoDynamic tuning charts (and I’ll pull a few plugs tomorrow) – I’m positive my SRT6 is just fine. Also pretty happy with the peak HP of 350.75 considering it was around 35deg warmer and a bit more humid today VS the weather last night.
DynoDynamics_3-1.jpg
Bottom line is make sure the Dyno shop and operator you use are experienced, that you know what to do and how to get your SRT into the proper dyno mode and don’t be afraid to ask for the Charts the way you want. I also suggest sticking with a DynoJet or Dyno Dynamics, or Superflow because it looks like the conversions are pretty accurate and solid.
Enjoy the weekend!!!!!
BB
Last edited by BrianBrave; Aug 29, 2008 at 11:42 PM.