Do I need to retune with test pipes?
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Joined: Oct 2008
Posts: 251
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From: Edmonton, Alberta
I am happy to hear that you have gotten away without a retune as that adds a lot of extra cost.
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Registered Member
Joined: Oct 2008
Posts: 251
Likes: 22
From: Edmonton, Alberta
This is correct in theory, but the practical ROI (HP/$) also comes into to play for most of us. I just don't see the value of paying $1K for a full tune to get maybe a 5-10HP gain. I could see it if I was going to a high boost pulley, but this exhaust change is pretty minor.
You won't care about roi when your motor pops due to running too lean. Just saying. It's worth at least getting AFR back in range. Ignition shouldn't need adjusting besides more advancement for power but we are talking safety strictly right now.
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Joined: Oct 2008
Posts: 251
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From: Edmonton, Alberta
I monitor AFR so I would immediately know if it starts running lean.
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Joined: Apr 2017
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Well, if you have already spent a couple of hundred bucks on an Intake system to gain 5-10hp, a couple of hundred bucks on a cat-back exhaust for another 5-10hp, and another couple hundred bucks on test pipes / high-flow cats for, again, that 5-10hp, then spending a few hundred bucks on a tune/re-tune for another 5-10hp is definitely worth the money 
And you'll definitely see the bargain when you race another G or Z with the exact same setup as you, but he manages to pull on your because he had that 5-10hp advantage from a proper tune
And you'll definitely see the bargain when you race another G or Z with the exact same setup as you, but he manages to pull on your because he had that 5-10hp advantage from a proper tune
This is correct in theory, but the practical ROI (HP/$) also comes into to play for most of us. I just don't see the value of paying $1K for a full tune to get maybe a 5-10HP gain. I could see it if I was going to a high boost pulley, but this exhaust change is pretty minor.
Registered Member
Joined: Oct 2008
Posts: 251
Likes: 22
From: Edmonton, Alberta
Well, if you have already spent a couple of hundred bucks on an Intake system to gain 5-10hp, a couple of hundred bucks on a cat-back exhaust for another 5-10hp, and another couple hundred bucks on test pipes / high-flow cats for, again, that 5-10hp, then spending a few hundred bucks on a tune/re-tune for another 5-10hp is definitely worth the money
And you'll definitely see the bargain when you race another G or Z with the exact same setup as you, but he manages to pull on your because he had that 5-10hp advantage from a proper tune
And you'll definitely see the bargain when you race another G or Z with the exact same setup as you, but he manages to pull on your because he had that 5-10hp advantage from a proper tune
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Joined: Apr 2017
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Well, in your case, your car is supercharged and not a typical all-motor bolt-on setup anymore, so you should car a re-tune anyway when switching from high flow cats to test pipes. The tune will shift enough to need a quick re-tune. You can have ten thousand gauges to log your car's performance, but at the end of the day, what does that mean to you? And the million $$$ question is, how much power are you putting down to the ground with your new test pipes? Did you gain or lose power? Nobody is convinced when your butt tells you the car "feels" faster or slower.
But anyway, going back onto the original topic, if you're not planning to re-tune the car to get the most gains out of the setup anyway, then why even bother doing test pipes in the first place? Might as well save that $1K on a tune, plus another couple of hundred bucks from buying a pair of test pipes, correct?
Unless you don't have access to a good local tuner, then that's different story. Otherwise, just remember, every horsepower counts when you're all-motor
But anyway, going back onto the original topic, if you're not planning to re-tune the car to get the most gains out of the setup anyway, then why even bother doing test pipes in the first place? Might as well save that $1K on a tune, plus another couple of hundred bucks from buying a pair of test pipes, correct?
Unless you don't have access to a good local tuner, then that's different story. Otherwise, just remember, every horsepower counts when you're all-motor I think you are missing an important point... it is not a couple of hundred bucks to retune on a dyno. I've had my car tuned twice and both times was well over $1K. My tune is already optimized for maximum performance. I am considering making a minor change to the exhaust system going from burned out cats to resonated test pipes. I am likely already at zero back pressure from the cats and AFR readings are fine at all throttle settings. And I don't notice any power loss. A 5 HP increase is withing the tolerance of measurement error. Even 10HP represents a 2% variance for me so doubt that would be a factor going against another car.
I think you are missing an important point... it is not a couple of hundred bucks to retune on a dyno. I've had my car tuned twice and both times was well over $1K. My tune is already optimized for maximum performance. I am considering making a minor change to the exhaust system going from burned out cats to resonated test pipes. I am likely already at zero back pressure from the cats and AFR readings are fine at all throttle settings. And I don't notice any power loss. A 5 HP increase is withing the tolerance of measurement error. Even 10HP represents a 2% variance for me so doubt that would be a factor going against another car.
1K is outrageous to just look at files and do some polishing. Hell ever thought about utilizing data logging and file transfer? That's what I did with Visconti, and I am happy with the reuslts.
