Any tuners here? Looking for AFR advice.

[cp-the-nerd]

I've been learning HPTuners since the beginning of the year, I'm taking it one step at a time and experimenting on my car (very carefully).

 

Right now I'm studying AFR and DFCO. I noticed that my Malibu (3.6L VVT, DOHC, port-injected) is commanding an AFR of 14.1 while cruising and 11.9 under Power Enrichment. Everything I've read says those numbers are very rich an N/A motor, should be more like low 15s and mid 12s respectively.

 

Anyone care to discuss this with me? Also if anyone is familiar with HPTuners, is there a simple method to bump up the commanded numbers so I can gauge any improvement? I can post the tune if someone wants to take a look.

[Drew Dowdell]

I wish I knew more about this. I'd like to put a mild tune on my Encore.

[cp-the-nerd]

Man, I wish my car was as easy to tune as the 1.4T. I could make a safe 20 hp and 30 lb-ft gain in 30 minutes on your car. There are tunes that make 200 whp on that powertrain. That's overkill, IMO, and not reliable, but it can make a healthy 160 hp/180 lb-ft on premium gas no problem.

Edited June 16, 2015 by cp-the-nerd

[Drew Dowdell]

Man, I wish my car was as easy to tune as the 1.4T. I could make a safe 20 hp and 30 lb-ft gain in 30 minutes on your car. There are tunes that make 200 whp on that powertrain. That's overkill, IMO, and not reliable, but it can make a healthy 160 hp/180 lb-ft on premium gas no problem.

 

Normally the car is fine, but this past weekend we had it loaded up with people and luggage. It was pulling hard over some of the western PA mountains and as such the fuel economy really suffered.   When it's just the two of us, we get 32-33 mpg on a trip... but this time we barely hit 27mpg... and that was driving conservatively.

[cp-the-nerd]

Do you run premium or cheap stuff?

[Drew Dowdell]

Do you run premium or cheap stuff?

 

Just 87.  Because I travel so much, I'm not the one who uses the car mostly and thus I'm not the one to fill it up.  That is my main reason for being shy about a tune that would be "Premium Required".

[cp-the-nerd]

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

[Drew Dowdell]

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

 

I'll try it out next time. 

[furioustee]

I am not at all familiar with HPT Tuners but I have been eyeing the Superchip Tuner I have seen while doing a research. I have read good reviews about it.

[David]

I have used the superchip tuner on my suburban and it really rocks for solid performance. I have it tuned nicely on 87 and if needed added power can change it to premium tune and get more out of it. I like that I can change it on the fly when the tank is empty and then fill up with premium and go.

 

I recommend using tuners to enhance the basic tune of an auto.

[Thed]

11's are definitely low. Crank that sucker down to 12.4 at WOT and feel the power. I'd still keep the cruising AFR where it's at though. You don't want to fry your cats, as raising the AFR too much is going to heat up your EGT's quick. 

[cp-the-nerd]

11's are definitely low. Crank that sucker down to 12.4 at WOT and feel the power. I'd still keep the cruising AFR where it's at though. You don't want to fry your cats, as raising the AFR too much is going to heat up your EGT's quick. 

 

Thanks man. Does it matter that the car is already set to hit 12.4 on pure gasoline? Power Enrich is programmed as a function of the stoich AFR (there's a multiplier table).

[Thed]

Is it the factory table or an aftermarket one? 

[cp-the-nerd]

It's factory. Stuck with E10 around here so the AFR drops.

[Drew Dowdell]

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

 

No real noticeable difference I think.

[David]

 

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

 

No real noticeable difference I think.

 

Best thing would be to replace the OEM chip with a Jet Chip and their Tuner so you can run in OEM tune mode, go to fuel efficiency mode or to performance mode. I have to say that I really like the ability to self tune your auto with preset tunes or if you want to play with it tune yourself to get the type of idle and performance you like out of the engine.

[cp-the-nerd]

 

 

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

 

No real noticeable difference I think.

 

Best thing would be to replace the OEM chip with a Jet Chip and their Tuner so you can run in OEM tune mode, go to fuel efficiency mode or to performance mode. I have to say that I really like the ability to self tune your auto with preset tunes or if you want to play with it tune yourself to get the type of idle and performance you like out of the engine.

 

 

A Jet chip?! I thought those were garbage. They are constantly posting "25+ Horsepower! 5+ MPG!!" on their product listings.

[Thed]

In the days of simpler MPFI systems I'd just say screw it and MegaSquirt it but you'd never be able to communicate with the transmission, ECU's or other "smart" devices in your car. 

 

Fun Fact: A new Volvo truck has on average seventeen different computers. One of these is the windshield wiper module, which also controls the exterior lights. Fun right? the KW's I work on are much simpler, with at least eight computers but no more than twelve for KW's made from 2010+ (the hardest part about it is knowing the CAN systems that the computers use to talk to each other (BTW, trucks have more complicated CAN systems than cars)).

[David]

 

 

 

You should try running premium before a trip like that and see how your fuel econ turns out. Couple folks at our old forum had Cruze turbos that loved premium, would get several more mpg and feel better doing it. Totally offset the cost difference.

 

No real noticeable difference I think.

 

Best thing would be to replace the OEM chip with a Jet Chip and their Tuner so you can run in OEM tune mode, go to fuel efficiency mode or to performance mode. I have to say that I really like the ability to self tune your auto with preset tunes or if you want to play with it tune yourself to get the type of idle and performance you like out of the engine.

 

 

A Jet chip?! I thought those were garbage. They are constantly posting "25+ Horsepower! 5+ MPG!!" on their product listings.

 

I took a 350 V8 and bored it out to a 402, hot cam, overall performance focused and with a jet chip it moves. I personally think JET chips work well.

[Thed]

Nothing beats a true dyno tune though...