Just Dyno'd my car... I'm a lil weirded out

[s14dude]

DLo just has a dope car. lol. HOt run!



yeah i am suprised those numbers are quite up there for having stock maf, smic etc......dont run that shit too lean and blow something up tho.

[DLo Eric]

Originally Posted by kassed33

ok, question...where are you getting the 18 for the A/F? according to the dyno(which should be ALOT more accurate than a A/F gauge you have on your car) you are at just under 12 which is right where you want to be on a turbo car. You should start off just under 14 at low RPMs then drop to around 12ish when boost kicks in and stay around there. Thats why the dyno graph has a red dashed line at that A/F ratio. And as for the power you are reading it is high for one of a couple reasons. First if you dont have a boost controller you could very likely be over boosting more thatn 10psi...you should really get one if you dont already have one, its much safer. Second the correction factor on the dyno should be the SAE correction (this is the number that everyone gives as the universal HP numbers, it makes the right corrections for temp, altitude, humitidy for your location. And third a dynojet is going to read higher than a mustang dyno. This is because a dynojet mesaures free spining torque with out putting a load on the wheels to simulate being on a road. But a mustang dyno, you have to put in the vehicle weight so the dyno can adjust for the accurate load on the wheels, and this type will give you a lower number because of this but it is a more realistic number, the actual HP you will have on the street. The stock hp for that turbo and engine should be 205hp and 203tq at the crank. The stock turbo will be safe to 13-15 psi. After that, the turbo is past its efficiency range, and power increases will fall off and are not worth the risk of turbo damage. The engine should produce 230-250 RWHP at safe boost. So your probalby around the 15psi range...well hope thats of some help for ya bro!

... HKS wastegate actuator. I'm getting the 18 A/F before I tuned it down to 12.

on another note I checked with another blitz gauge and its reading 12Psi and as far as boost spiking the actuator I have has never spiked.

Also forgot to add I have a walbro since that might be brought up in figuring out why it was running so lean before the SAFC tune

[BigVinnie]

Originally Posted by orion::S14

Whoa...I hate to get off-topic here...BUT...

That's 100% incorrect.

A proper A/F for a turbocharged motor is ~12:1 or so AT THE LEANEST.

Run +13:1 at ~10-12psi on a SR and you'll HEAR the knock, and possibly break the motor.

But don't take my word, I'm not a tuner...maybe listen to Garrett:



From here: http://www.turbobygarrett.com/turbob...tech102.html#e

- Brian

Yep your right the ratio is more consistent with Natural Aspiration than it is for turbo charging.

turbobygarrett
The turbocharger increases the density of the air resulting in a denser mixture. The denser mixture raises the peak cylinder pressure, therefore increasing the probability of knock. As the AFR is leaned out, the temperature of the burning gases increases, which also increases the probability of knock. This is why it is imperative to run richer AFR on a boosted engine at full load. Doing so will reduce the likelihood of knock, and will also keep temperatures under control.

There are actually three ways to reduce the probability of knock at full load on a turbocharged engine: reduce boost, adjust the AFR to richer mixture, and retard ignition timing. These three parameters need to be optimized together to yield the highest reliable power.

That means in the scenario of AFR being between 12.7:1-13.2:1 and running boost higher than probably 7PSI (Garret stated higher 10-12PSI) mixture should in fact be richer (AFR 11.4:1 on average, which would vary from displacement/load) and ignition timing should be retarded. So any mixture running richer than a an 11:1 could increase ignition timing. My fault, still stuck in Natural aspiration....

[NemeGuero]

18 at idle isn't too too bad. But under load that sucks balls. hahah

full boost/load should be 12ish... as has been said.

Go to a non-newb dyno place. haha

[S14DB]

Oh knowes danger to manifolds1!!

[BigVinnie]

Originally Posted by S14DB

Oh knowes danger to manifolds1!!

LOLS I think you just proved that any conversation with a turbo charged engine with an 18:1 ratio is impossible..........LOL
Although that graph is fake...

[S14DB]

Originally Posted by BigVinnie

LOLS I think you just proved that any conversation with a turbo charged engine with an 18:1 ratio is impossible..........LOL
Although that graph is fake...

nope, ran it for 2 yrs with that or leaner...

Before I tuned it.

[johngriff]

OMFG what is with the nightmare A/F ratios? Dont let me get all jimwolf up in here, but i wouldnt go past 11.6 at the leanest when pushing more than 12psi.

Changing the timing isnt going to affect EGT's which "in turn" will effet af/r. Changing the timing on a SR.... LOL. If you think you can set the timing by the cas GTFO.

Oh yeah, do they do installs too?

[BigVinnie]

Originally Posted by S14DB

nope, ran it for 2 yrs with that or leaner...

Before I tuned it.

That my friend is super nutty....... The loop de loop is something I don't see.....Why did the charts change???

[S14DB]

Loop happens when you have tranny slip. 2 different dyno's.