Dyno tune tomorrow

Tech discussions on the L77 6.0L V8.
CrashTestDummy
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Location: Pearland, Texas

Re: Dyno tune tomorrow

Post by CrashTestDummy »

I can't speak specifically to the Caprice factory tune, but most late-model GM tunes are actually a bit lean. This, depending on other factors, and there are a lot of them (change one map, and you have to find and change a few others, that lean tune can hurt MPG. I think it causes you to be more in the throttle to get the same performance, so you're using more fuel (well, using more air, which results in you using more fuel). Many tunes will enrich the mixture map up a bit, and add more initial spark. As long as you aren't getting spark knock, that can definitely help performance and mileage.

There's also the 'torque limiting' portion of the tune, which, depending on the vehicle, can really affect the driver's sense of drivability. On our '10 Tahoe, there was a distinctive flat spot at throttle tip-in when leaving a light, or stop sign. Our tuner tuned that out, which, to me, was worth every dollar we paid for the tune alone. He also firmed up the shift points a bit, which helped drivability a bit, too.

Some will want to tune out AFM, which can be annoying in some instances. Since our locale is pretty flat, we kept it, which will help mileage where we drive most.

There's a lot more that can be adjusted
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
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bsparks72
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Joined: Tue Jan 20, 2015 9:29 pm
Location: Katy, Tx

Re: Dyno tune tomorrow

Post by bsparks72 »

Navy Lifer wrote:
bsparks72 wrote:I'm also sticking with 87 octane.
So many questions....sorry!

What did the tuner have to say about this (sticking with 87)?

If the ECM was already "optimizing" timing, is the power increase based on more fuel (richer) or less (leaner), given the limitations of the fuel choice?

Did he suggest what the impacts might be if you run higher octane with the same tune--or whether he thought it was really worth doing an 87 octane tune? Obviously the tune made a difference, so it wasn't just a matter of him taking your money. The bottom line for me is whether it does any harm to reliability/durability.

How much of the power increase comes from the differences made in the transmission (not that it "makes" power), whether through better shift efficiency or other tweaks--torque management, etc?

Did you specify what you wanted as far as the shift firmness, and are you OK with how it is now?

Is there any indication of spark knock?

Really interested in what happens to your fuel economy, between tune & AFM delete. Please let us know!!!

And....Happy Birthday!
I didn't ask a lot of questions, and just told him it's my daily driver that goes about 75 miles per day, in either stop and go traffic or at highway speeds. He said he can get a "decent amount" more power on a 93 tune. I don't know what that means in real-world numbers. I would venture that it's in the single digit gains over my tune, but I don't know that. I know he reduces but doesn't eliminate torque management. He basically did his thing, then we went for a drive. He asked if the shifts were too firm for me, but they were spot on. I hate a lazy shifting automatic! At full throttle I did chirp 2nd gear one time. There's no indication of spark knock, and I'm not sure if I'll try anything other than 87, unless I get an indication of knock.

As far as fuel economy, I've reset it in the info center 3 times (I know this isn't spot-on accuracy, but I figured that back-to-back numbers might give me some indication). My overall fuel economy had leveled out at 18.1 over the past several weeks prior to the tune. On the trip home, I was showing an average of 17.8mpg. Keep in mind that a lot of that was on I-10, where there are 75mph speed limits...and I was going a tad over that. At 70 it looks like it will get more around 20-21. I honestly don't think that disabling AFM will affect me much, as my driving conditions on the freeway don't let it come on very much at all (usually 75mph or more, and up and down overpasses or dodging traffic). I've rarely seen it on longer than 10-15 seconds. It was more of an annoyance, and since I put the mufflers on it on Friday, the tone was not pleasant. The seat-of-the-pants is noticeably better, and I really like the better shift map. It just seems to pick the gear changes at more appropriate times. I drove the car 2 hours home, and I drove it another 2 hour round trip today. Time will tell, but at this point I like it quite a bit better than I did.
-Brandon
2012 9C1 L77 - 228/234, .604/.609 112 cam, JBA shorty headers, Solo high-flow cats, X-pipe, Cherry Bomb single-chamber mufflers (Frankenstein exhaust), Roto-Fab CAI, CTS-V torque converter, 3.45 Camaro diff, G8 red/black seats/steering wheel
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GTObert
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Location: Jordan, MN

Re: Dyno tune tomorrow

Post by GTObert »

Navy Lifer wrote: If the ECM was already "optimizing" timing, is the power increase based on more fuel (richer) or less (leaner), given the limitations of the fuel choice?
The ECM is definitely not optimizing timing. Most of the power gains realized are from advancing the timing and reducing the sensitivity of the knock sensors. A/F ratio does make a difference at WOT, but the most noticeable thing in my opinion is the increase in part throttle power and response that you get from advancing the timing.
2011 9C1
2005 GTO
xcidmigs
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Re: Dyno tune tomorrow

Post by xcidmigs »

I emailed The Guerra Group to ask if they will sell the same tune they just did via mail and heres the reply:

"I'd be happy to sell you a tune through the email for your Caprice PPV. If you're interested in the remote tuning option, you have a couple of choices. If you own EFI Live or HP Tuners, I can send you tune files through the email and continue to update the calibrations until you are satisfied. The cost for my email tune support is $300. If you don't own any tune software, I offer HP Tuners or EFI Live at a discount if you bundle it with my tune support. I offer HP Tuners Standard for $449 or HP Tuners Pro for $599 and EFI Live Flashscan for $799. If you are looking a more cost effective way to tune your own vehicle, I have a nice solution:

You purchase an EFI Live AutoCal device from me for $350 shipped to you.
You read your ECM and TCM tune calibrations and send them to me.
I modify your tunes and then e-mail them back to you. You transfer them from your PC into the AutoCal which you then take out to the car and load in the new Patrick G ECM and TCM tunes. You can then data log with the AutoCal to check fueling, timing, and shift behavior. You then e-mail me the logs. I will in turn make modifications based on those log files. I send you revised tunes until you're completely happy. What's great about this approach is you can enjoy the benefits of the tune with your current mods, then get 3 free updates for when you add mods in the future.

The cost for my email tune support is $300 per vehicle. This fee covers up to 3 complimentary tune updates to your vehicle. A typical update would be things like adding a high stall torque converter, a gear change, an aftermarket cam, or a supercharger upgrade. If you make changes beyond the 3 updates, the cost per additional tune update is $50.
So to recap, the entire cost would be $650 for the Autocal hardware and the tune support. It would be $749 for HP Tuners Standard and tune support. It's $899 for HP Tuners Pro and tune support and $1099 for EFI Live Flashscan and tune support. "

So thats $650 at a minimum which makes me think you are better off going to a local place and having a dyno tune done on your car in person which around me is priced around $450. I realize that makes it impossible to remove yourself if you want to consider that factor as well.
motorhead
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Joined: Sun Nov 24, 2013 6:15 pm

Re: Dyno tune tomorrow

Post by motorhead »

Any Tuners for Caprice 6.0 L77 in MA or NH? Sounds like some great results. Thanks.
motorhead
Posts: 32
Joined: Sun Nov 24, 2013 6:15 pm

Re: Dyno tune tomorrow

Post by motorhead »

Any Tuners for Caprice 6.0 L77 in MA or NH? Sounds like some great results. Thanks.
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bsparks72
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Location: Katy, Tx

Re: Dyno tune tomorrow

Post by bsparks72 »

Today's road trip: 365 miles. According to the info center:
Average speed - 71.1 mph (yeah a lot was done at 80+)
Fuel economy - 19.6

I didn't manually calculate fuel economy so take it for what it's worth.
-Brandon
2012 9C1 L77 - 228/234, .604/.609 112 cam, JBA shorty headers, Solo high-flow cats, X-pipe, Cherry Bomb single-chamber mufflers (Frankenstein exhaust), Roto-Fab CAI, CTS-V torque converter, 3.45 Camaro diff, G8 red/black seats/steering wheel
Gerome
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Re: Dyno tune tomorrow

Post by Gerome »

Sounds like some numbers I could live with .
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The Tech
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Re: Dyno tune tomorrow

Post by The Tech »

My tuner told me the difference between 87 and 93 octane would be about 25 hp so I switched to 93 before my tune. I saw a two mpg increase over the 87 with the extra power.

Mine dyno'ed at 373 rwhp and 390 lb/ft.
2011 Alto Gray Caprice PPV 9C3, Kooks Long Tube Headers, Kooks Drag Cats and Crossover, Solo Axle Back System.
1996 DGGM Impala SS
1995 Caprice 9C1 red over white
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