On Friday, I had my vortech installed on my '05 G35 coupe and tuned by CP Racing and this is what I got on their dyno dynamics:




Then I dyno'd the very next day on a Dynojet and this is what I got:






The a/f readings seem to differ greatly. What do you guys make of this?

Also...I have the zeitronix and have pulled some runs and data logged it but the rpm reading is messed up so I only have a/f as it pertains to boost

Here is a 12 second WOT 1-2-3 pull on an on ramp recorded from my Zeitronix wideband data log....(it has been attatched to this post)

What do you guys think....

 

1) Where were the readings taken on the respective days? Tailpipe? Bung? Factory 02?

2) What were the atmospherics on the 1st day? Similar to day 2? Different?

3) Was the Dyno Dynamics dyno fitted with the PAU (power absorbtion unit?)


The big question is #3. If you were running a load-based dyno (Dyno Dynamics w/ PAU) versus a standard dynojet (non load-based), this could explain the differences in A/F.

 

the dyno dynamics dyno was not loaded

jason it all looks good to me we just need to work on the rpm reading.
i would def believe what your zeitronics guage says over anything next level performance dyno says. they used sniffer and you zeitronics guage and your dyno from cprace was taken in you crawford cat. so those readings are goin to be more acurate.

remember when they had the sniffer on neffsters car and it was reading .8 than his wideband was and when they changed it to the cat it when back down. incase you dont remember im sure todd does!!

 

No I agree with you Dan about the dyno jet numbers. I am more concerned with my Zeitronix reading too. I have no idea how to fix my rpm thing so I have no way to read the data properly. I have made an appointment for Friday 4:00pm at Coastal Dyno to re-tune. You are more than welcome to come if you want.

I just spoke with Sam at Coastal Dyno and he said the dyno dynamics is load-based and dyno jet isn't. If I could get my rpms to work, I'd be happier knowing exactly where I am. I don't know enough about the ECU to figure this out

 

damn it

i work on friday at 4 till 9. that is no fun.

i posted in your other thread what could be the problems with teh rpms

 

If Randys_g is right and you should tune to boost and not RPM...at what point in the boost curve should your a/f be below 12. At what point is 12.5 too lean?

 

You have a supercharger so the two will definitely be related. Turbocharged car, different story. Come to think of it, our cars have no real way of telling tps so it has to be tuned by rpm and map/maf.

 

His problem is a slipping belt . Ive seen the CP chart and his Zeitronix file . His belt was slipping a little on the CP dyno up top after 10psi . Showed the same thing on his Z file . A couple hundred miles later....he is only getting 7psi on the Dyno Jet dyno and his new Z datalog file . The car wasnt tuned at 7psi and now the A/F is off . Just needs to tighten his belt