So I had my car dynod today at the ced meet. I put down 283hp and 296tq. My afr was at 13.1. I already talked to a few people at the meet about it and they said I should have been a bit higher. What do you guys think. Mods in sig

 

Seems about right, as far as the AFR that's about what I have seen in other TC cars. Someone with more experience in that matter may be able to provide you with more info. As far as the HP/TQ it seems about right.

I know it's probably not practical for you, but I would be interested in seeing what difference it makes if you had the same mods, but the stock intercooler. I would like to know what the numbers are on that one.

 

It seemed to me the guys runing the dyno were a bit confused on every other car, It was the 1st time i've ever seen cars dynoed, so i don't know for sure, but they seemed a bit lost. I did hear some older guys taking in the shop saying that the results from that dyno would be unreliable.
I thought your ss performed great at the dark knight cruise.
Let me know if you guys do any get togethers, I'll be there, had a blast !

 

I'm not an expert on this engine but that A/F is quite lean compared to what other cars with turbos look for under boost.

 

The reason the AFR is where is it is because if the DI. Ive heard that the normal range is 12.8 to 13.2.

 

I don't understand what you mean, sorry?

12.8 to 13.2 is still lean on a turbo engine, I'd be interested in knowing what it is on a stock SS.

 

Yeah me too. I mean im not really worried because if something messes up then the dealer will fix it lol

 

with a computer controlling the mix I don't really think thats too lean..the system is quick to correct any problems. And with todays emmissions thats about right.Lean actually produces more power as all the fuel is burnt while keeping cylinder temps high.A fat mix tends not to burn completely and results in lost power and cooler cyl temps.Now if it were a carburated car..I'd be worried as carbs are not known to maintain constant AFR's throughout the entire rpm range and you will run into leanout conditions somewhere in the rpms range.Gotta love 'puters!! God thing its not windows based....or is it.........

 

From Garrett's website

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

Leaner AFR results in higher temperatures as the mixture is combusted. Generally, normally-aspirated spark-ignition (SI) gasoline engines produce maximum power just slightly rich of stoichiometric. However, in practice it is kept between 12:1 and 13:1 in order to keep exhaust gas temperatures in check and to account for variances in fuel quality. This is a realistic full-load AFR on a normally-aspirated engine but can be dangerously lean with a highly-boosted engine.

 

ahhh,,,but since these eng 's are monitored and controlled this is not an issue if knock is the main problem . This is why we can run 87 on a non staged motor....timing and fuel are immediatly corrected to control this..way before we actually will be able to hear it.I doubt very much if GM would allow their bread and butter to operate in a zone that will wind up costing them rework money....this applis to electronic FI eng only. Remember we are talking factory settings made for everyday all conditions driving, not purpose built machines.