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Discussion Starter · #1 ·
In an in depth conversation with one of the owners of Vararam today, this was a direct quote from him.

The conversation was about the hand held tuners that are sold, and the problem they seem to have with the Vararam Intake. While the stock tuning is able to adapt to the leaner conditions caused by the ram air action, the handheld tuners are not, according to Vararam.

I was getting detonation with the Predator tuner which was not there with the stock tuning. Also, there was no more power to be had with the Predator, only detonation.

Vararam said if you have the Vararam, you DEFINATELY do not want the Predator tuning in the ECU. He says that Predator contacted them for a fix for this issue :eyes:

Lastly, it was a blanket statement from Vararam that the fastest Zs are running stock tune, and it is best able to adapt to most non forced induction mods the best.

That is all.
 

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With the stock tune, my LTFT's were 15+ points lean.

Adapt? Yes, the LTFT's do that. The problem is that when you go WOT, the LTFT's lock at zero and your WOT is too lean.

I contacted Vararam for suggestions MAF table tuning and got nothing. It is clearly not stock. On my speed density tune, all my LTFT's are zero-ish, enable the MAF and bang, 15 points positive. Don't get me wrong, I like my Vararam, but their support left me with an uneasy taste in my mouth.

John.
 

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I don't know how the GM PCM works yet, but on a Ford at WOT it just looks up a value in the PCM. Nothing to learn, you are in open loop mode at WOT. If GM is the same way (I would think that it would have to be because it also uses narrow band) then Vararam is only talking about closed loop mode, not WOT which is what your implying.
 

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"Fastest" means WOT to me. But then again, I could be wrong.

:)

John.
 

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LOL -- no problem. :)

John.
 

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All the fastest cars with vararam and stock tuning but when you have a honkin cam or FI stock tuning is not where it is at.

I see his point with stock cars and vararam but the fastest Z06's are not running stock tuning or even stock cubes for that matter.

I am pretty sure of that. It's a good point though for close to stock cars with vararam and i don't dispute that at all.

If vararam leans you out then the last thing you need is some tuner leaning you out more cause you'll detonate and the car will pull timing.

Same thing with trying to run more octane than you need on a stock motor as you might just lose power.

You need tuning thatthe mods you have not just blindly plugging in a predator tune and running with it. With each mod of significance you should do a wide band O2 dyno pull to see where you are and adjust the tune accordingly.
 

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pat03z06 said:
All the fastest cars with vararam and stock tuning but when you have a honkin cam or FI stock tuning is not where it is at.

I see his point with stock cars and vararam but the fastest Z06's are not running stock tuning.
:yeadog: My car barely runs with a stock tune...you need tuning with a highly modified car.
 

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The Predator is made by Granatelli, and their reputation is not so good with those who have done business with them. (If you like you can search my topic titled "Granatellis are crooks") Therefore, I would have no confidence in their programmer.

Tuning makes all the difference, if done by a professional tuner.
 

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Innovator said:
In an in depth conversation with one of the owners of Vararam today, this was a direct quote from him.

The conversation was about the hand held tuners that are sold, and the problem they seem to have with the Vararam Intake. While the stock tuning is able to adapt to the leaner conditions caused by the ram air action, the handheld tuners are not, according to Vararam.

I was getting detonation with the Predator tuner which was not there with the stock tuning. Also, there was no more power to be had with the Predator, only detonation.

Vararam said if you have the Vararam, you DEFINATELY do not want the Predator tuning in the ECU. He says that Predator contacted them for a fix for this issue :eyes:

Lastly, it was a blanket statement from Vararam that the fastest Zs are running stock tune, and it is best able to adapt to most non forced induction mods the best.

That is all.
I recently installed a VARARAM then took it to have it DYNO TUNED first pull factory tune 345RWHP 341 RWTQ last pull after LS1 EDIT tune 370 RWHP 358 RWTQ a good tune makes a difference.
:cheers:
 

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Discussion Starter · #12 ·
OLDGUY said:
I recently installed a VARARAM then took it to have it DYNO TUNED first pull factory tune 345RWHP 341 RWTQ last pull after LS1 EDIT tune 370 RWHP 358 RWTQ a good tune makes a difference.
:cheers:
If leaning it out and adjusting some parameters gives you more HP, why didn't the GM team tune it as such? Perhaps there are reasons we are not aware of? Emissions would be lower with more advance and less fuel :screwy:
 

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The stock tune is ok, even if you have a cai and headers, as
eventually the car will learn the mods somewhat.

However, a "good" tune from someone that knows what their doing makes the car run smoother, and cleaner. Not to mention some additional sotp difference and better gas mileage.

Guess you have to decide if you want to spend $400-$600 for a "good" tune using HP-Tuners/LS1Edit.

augydog :cheers:
 

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Runner richer at high rpm/load is cooler EGT's, and easier on the cats. Leaner is harder on the cats for sustained operation. (don't the factory emissions cats have to last 60k or 100k (under warranty) by law?)
 

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Innovator said:
If leaning it out and adjusting some parameters gives you more HP, why didn't the GM team tune it as such? Perhaps there are reasons we are not aware of? Emissions would be lower with more advance and less fuel :screwy:
I'm no expert but like mentioned above it must be warranty . Lets face it the more HP you squeeze out of an engine the more stress on the parts so GM de-tunes and hedges there bet JMHO. My tune was done by the VETTE Dr.'s and Carman told me GM leaves a lot on the table with the factory tune on ALL of there cars not just the VETTE'S .
Bob :cheers:
 

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Discussion Starter · #16 · (Edited)
Yes, such is the case with a forced induction car, like the Audi S4 for example, which has near 100 HP left on the table. But on N/A cars, I've never found tuning to make a significant difference, and it seems that this car is no exception.

Now if the car has extensive mods like a cam, head work etc, I can see the need for a custom tune. But since the MAF sensor reads the total volume of air and is supposed to adjust for variables, it seems pointless to tune a mostly stock car. My car is in fact faster with the stock tune, once the ECU ‘learns the timing curve. Upon a fresh reset, the car will actually be faster, running like a happy idiot, detonation and all. This is what I believe to be “my car is faster with the custom tuning I just got" false perception. What happens after several hundred miles though? Ya, it probably goes back to the HP/TQ it had before, give or take a little.

I've heard lots of talk about how you need to get your fuel trims near 0 for optimal power, but this makes no sense. LTFT is solely determined by the 02 sensors, which become inactive on WOT, where the TPS and MAF do all the air metering measurements. So, what do the LTFT have to do with open loop WOT tuning? :mah:

'Learn' me something if I'm wrong here.
 
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