sgtdestruction

iTrader: (1)

So I have had my 2007 V for 9 months and have yet to do any mods myself. Purchased the car with MagnaFlow catback exhaust and no cags, but otherwise stock.

I love the exhaust note, but want a little more noise. Debating between MagnaFlow high flow cats (no plans for headers) or DMH elec. cut outs for that extra sound.

However, contacted a tuner in Atlanta and asked about a tune after one of the above installs. Was quoted $590 for a "complete dyno tune".

So...thoughts? Should I go with the cats or cut outs? Is it worth the extra $600 to get a tune after these upgrades, or am I wasting money?

isis

iTrader: (1)

A tune is always the best thing you can do if the car is anything but stock. Even a stock car can feel a lot better and improve mileage. I don't know if 590 is a lot or not. Seems like simple mods regardless of the hardware so I don't know how to evaluate the money. I'd do it myself for that money.

MylesF7

Tune will definitely help... A lot... But if you plan on more mods in the near future you may want to hold off till you do those.. Some tuners will retune for free, if thats the case go ahead and do it...

Who's the tuner you contacted?

etcts-v

Anytime you add any modifications that will change the nature of the airflow in your motor then you want to get a tune as the computer is basing it's fueling calculations off of stock parameters. If you throw on mods with no tune, you run the risk of running lean and/or rich which is not good for the motor, especially want to stay out of lean conditions.

That said a cat-back isn't going to have much of an impact, it is after both O2 sensors so you are still getting good readings in the PCM on fueling results. It will still be working off stock maps but you should be fine without a tune as far as engine safety and reliability goes.

As far as the gaining from the tune, you are going to gain horsepower and torque from a good Dyno tune regardless of the mods, even on a stock motor you can get gains by pushing out of the box GM factory tuned into. How much of a gain? Not huge, but most dyno shops will give you a reduced rate to come back in after you add another mod as it won't take as much time for them to modify their original tune as opposed to a whole new map.

If it were me I would go with the Cut Outs, best bang for your buck at the moment. Then save up your money for a few other mods like headers and a tune at the same time. Headers and a stock Airbox mod would require a tune. just my .02 cents!

DMM

Hold off on the tune until you step up to headers. While not ideal, the LTFT's can compensate fairly well until you get into headers and cats with a modded airbox. Once you do this, your fuel trims will likely be well in excess of the +10-15 range, plus you'll want a little more timing in the midrange and top end, along with zeroing the torque management.

Do yourself a favor though, go to the Tuning and Diagnostics section here and inquire about a well known Tuner in your area. Lots of hacks out there that don;t know what they're doing.

James@ShorTuning

Go for it! Def some gains there as the factory tunes aren't very aggressive. Give me a shout if your interested. Might be a bit closer and save u some money at the same time!

To save more money I would do the planned mods prior because depending on the mods will require a full retune.

DMM

^ Use vendors like this guy.

isis

iTrader: (1)

If you're simply looking to draw a line, the cutouts are downstream from the cats. If you do them and keep the stock cats, the computer should still be happy. If you change the cats, you'll need to deal with an obdii cat efficiency code which needs to be tuned out or eliminated. So if you want to save the money on a tune, cutouts won't need anything like that.

It's mostly just a noisemaker at that point, but could be useful down the line. I'd do a tune, but find somebody cheaper. Or learn that yourself. It's not terrible if you are fairly mechanically inclined, halfway computer educated, and patient as hell.

It's money well spent once you can do it yourself.

sgtdestruction

iTrader: (1)

Thanks for the great info everyone. I had emailed Vengeance Racing and received the dyno quote from them. I previously had a z-28 a few years ago, and did some light mods, but never went so far as spending more than a few hundred in the engine.

However, the V is begging for more power and efficiency, and I am inclined to oblige.

James, PM me about your shop, as I have a few friends in Bowling Green that may be interested as well.

BudRacing

iTrader: (3)

I had mine dynotuned at MTI for $400 over the summer. I'm fairly happy with my results, but have nothing to compare that too. The service was good and I got a chance to talk to the tuner afterwards. For what it's worth, Vengeance seems more drag race/peak oriented whereas MTI seems to be more road course/smooth power curve oriented.

sgtdestruction

iTrader: (1)

Thanks Bud...I will def keep that in mind if I contact them again.

odthetruth

iTrader: (4)

Headers, then either cat delete or high flows with a tune. You should pick up a decent amount. I paid 500 for tune. 500 seems to be the solid rate for a tune. I wouldn't really pay higher.

Ron@Vengeance

iTrader: (51)

FWIW, our primary customer base is high performance street cars.. We have tuned over 70 NEW (and countless Gen I/II) CTSVs with various modifications. Our focus is on a COMPLETE street and dyno tune for optimal performance both under the curve and peak. We offer 12 months free updates with our tunes and an additional 12 month prorated updates for those who continue to modify their vehicles.

Im not taking away from any other shops mentioned, but we are DEFINATELY more than simply a drag race shop...

To the OP, I would suggest a tune over the cut outs. The tune will optimize your combination and ensure safety/reliability while increasing HP/Torque thru the entire RPM range. As James said above, the factory tunes leave alot on the table. Goodluck with your decision. If we may be of any help please do not hesitate to contact us.

BudRacing

iTrader: (3)

Thanks for clearing that up Ron.

sgtdestruction

iTrader: (1)

So here is the quote from Vengeance:

DMH Electronic Exhaust Cutouts: $399
Installation (Weld/Wire): $425
Completed Dyno Tune: $590

Total: $1,414

Not judging Vengeance, but this sounds like quite a bit to me. Or am I completely off base and this is normal cost?

sgtdestruction

iTrader: (1)

Thanks for the assistance Ron...I really appreciate you and your team taking the time to answer my questions and shoot me some quotes.

JDB

iTrader: (2)

Why would you spend anything on cutouts that are just noise at your mod level? For that $824, that's practically the price of Kooks headers.... and then you said to add cats with your cutouts ...$290-310 range for these only.... might as well buy Kooks connectors for your headers.

MN_V

iTrader: (5)

Add headers and cats and you'll probably get the sound you're looking for and a performance increase that will make a tune even better!

Isaacs

iTrader: (1)

PM sent...A dyno tune is definitely beneficial with any mods. They'll clean up the fuel/timing, eliminate the GM torque management crap and skipshift bullshit. You should pick up some power and get a good baseline for any mods you plan on doing later. The first visit is usually the big one, then its cheaper every time after that.

MylesF7

FWIW I'd rather take my car to Vengeance than MTI.. JMHO