Ok guys...here it is. Now that the 6 is back up and running, here's my dyno chart. The end result was 456 at the wheels, so using 20% drivetrain loss (seems consistent, given the 307 rwhp stock run), that puts it right at 570 hp at the crank. Keep in mind the wheels haven't gone on yet. After the wheel weight numbers came back I realized I wasn't saving as much as I thought, but still probably around 15 lbs of rotating mass which should help.



As you can see, by 4000 rpm there's a 60+ hp difference at the wheels, which rapidly increases. By 5000 rpm the difference is over 100 hp at the wheels (120 at the crank), with a peak difference of 163 rwhp (204 at the crank at 6250 rpm. It looks like it flattens off from 6250 to redline, but the power doesn't drop off. It will stay in that sweet spot of 100-200 hp difference during straight-line runs as the rpms don't dip below 5000 when shifting at redline in any gear. I haven't seen the torque curve yet, but I'd expect good gains across the power band.

 

Wow, that is quite impressive! Congrats! It will be a blast to drive. I'm looking forward to hearing about your real world experience and thoughts once you have the car back and have had an opportunity to drive it around some.

BTW, I see your signature says South FL and Reno. Where will the car be located? I am taking a vacation to FL in December and I would love to see your car.

Adam

 

Wow, what a difference! That's awesome. BTW, the 307 number seems a bit low. HP climbs linearly right up to the limiter (~7300), but it looks like the stock run was only done to 6750.

 

I don't know the exact rpm at which the car made the 307 in stock form. I do have the original dyno but it's small and hard to read. The data showed that the car made 299 hp at 6500 and 304 at 6750. Presumably the 307 hp came somewhere around 7000 rpm, but the data ends at 6750. It was reported to me though that the peak power the car made was 307 on that run, but I don't know if they ran it to redline because I wasn't there.

 

Awesome dyno Mark. Those numbers are right in line with mine on an RPM to RPM comparison. That car should really fly now! Watch out for that rev limiter, it comes up quick!

 

My assumption is the RED run in the plot is your base run without charger. If so the car war running extreemly rich for an NA car, that would result in a loss of power for sure and may explain the 307rwhp of your base run. I am guessing but running that rich would account for a 10-20HP loss maybe even more. As far as your after run goes, ask your tuner to reprint your run with the HP and TQ numbers with AFR, and if he was logging boost that would be nice to see as well. Since he is using a DynoJet he may even have their OBDII plug in, this would allow him to log and plot all of the OBDII data and graph it with the HP and TQ, this info can be very helpfull in working in the tune.

Looks good so far, without more info it is hard to say what is happening from 6300-7400RPM that area looks like either the blower is running out of air or the tune may need a little more work to smooth things out.

Without a doubt it will be a blast. Keep us informed.

Dave

 

Yes good eye. The stock tuning on the Vantage is very rich...some tuners have gotten 20-35 hp just from changing the A/F mixture.

The peak hp does come surprisingly low at 6250...I wonder if it would be different on the road with better airflow.

 

Not likely, the Vantage uses a MAF (Mass air Flow) sensor to measure the air then determines the amount of fuel to add, more air more fuel, so the amount of fuel for any given amount of air is controlled by the ECU. If you had more air the ECU would just add more fuel untill it reached the target in the fuel tables of the ECU.

Another variable would be engine coolant temp, if the car was on the dyno and allowed to get hot from not having any airflow accross the radiator, then the ECU would command more fuel and less timing to try and reduce heat buildup in the motor, but AFR's of 10:1 are still considered very rich even if the goal was for using the fuel to cool the cylinder & piston. This is why when running on a dyno you set up large fans to reduce heat in the coolant system. It is also helpful to have the ability to log the OBDII data and then you can look at all the variables as needed.

What mods did you have on your base run?

Dave

 

The stock AFR tables for the vantage runs very rich in open loop. Add in some LTFT correction and you can easily get richer than 10:1. Thats my experience as well.

 

I have been thinking about this even more, our Dynojet only measures to 10:1 AFR and looking at the base run again I am sure the car was running richer than 10:1 from 5500 to 7000rpm. This is a serious issue; even in Hi Compression NA motors AFR's that rich will cause long term issues with the health of the car. The O2 sensors will live a very short life and worse yet the fuel will wash down the cylinder walls and cause premature wear of the rings. Other issues are diluted oil and premature bearing wear. I am not saying this is going to happen to every car running in the 10:1 AFR range but it is very possible.

It may be time to start gathering some data, to find out if this is normal or abnormal. Are there any other base run dyno sheets the AFR that anyone has posted or is willing to post? Has anyone had there oil tested and willing to share the data?

By the way does anyone know what tuning software is being used to flash the ECU, or are they changing a chip in the ECU?

Dave

 

Apparently it's "normal" in the sense that it's the stock tune. ESX said they are all like this...they run very rich. It certainly supports RSC's statement that AM left a lot of HP on the table, whether it was to not get too close to the DB9's output or to just be conservative. Whatever the case, even without a SC kit there's a lot of HP to be gained from a proper tune and it sounds like longevity would be improved as well.

 

Here is my stock dyno. Also rich!.
ECU is typical Motorola mpc565 processor but a BDM module does not connect to the Aston Martin board. A custom solution has not yet been developed(which pins and how to talk to to them). Great job for an ECU hacker.

 

Wow that is a big gain! Is it only for ECU tune?

 

I see you supercharged it. Missed the thread. thats an impressive gain. Hows the ride?

 

I think you're speaking a lot of sense. We've certainly found that the AMV8 produces larger than usual gains on a NA remap, but more interesting is your comment on O2 sensors. I've now seen and heard of a number of cars that are killing O2 sensors in similar sorts of mileages to the clutches (around 15,000). We actually lost nearly 2 days of time when we were mapping the RSC supercharger on the rolling road because of a misfire eventually traced to a faulty O2 sensor.

Funny that the assumption typically is that the OE map is the safest and the aftermarket ones are stressing the engine! Not always the case!!!