BMW540-G8GT

I've had my G8 GT for about 3 weeks now and love it. I have been researching the intakes and exhaust for a first mod. I'm thinking around $500 for the first "installment"/mod. There are some nice intakes and exhaust so help me decide which to do first.

Intakes: Vararam or Rotofab - I am attracted to the power gains of the Vararam but not the install with the radiator leaning back, etc. The Rotofab looks fabulous and sounds like it has decent gains and sound also. Of these two, not sure which to choose. One of these will cost around $300.

Exhaust: I've decided the Solo axle back w/J pipes sounds pretty darn sweet and can be bolted on by myself (and stock replaced for road trips with family, etc). This will cost just under $500.

I've started doing the lower front grill mod (opening blocked off honey combs) and was thinking between this, the lower panel mod and factory snorkel mods that these might bring extra horses to the intake. I haven't taken the stock airbox off yet to see how well its designed but I have read that some guys who have done the free diy mods have noticed nice gains from the increased airflow to the stock airbox (makes sense to me). Maybe this is good enough as far as intake and I should do the exhaust first, since this stock exhaust is too quiet. At the same time, I'm guessing the axle back won't bring much gains like a Vararam or Rotofab.

Whether it's an intake or axle back it's less than $500 for my first mod. So, which one should I do first?

nda9090

Congrats on the G8. You won't get much HP increase from the axle backs. The main area of restriction on the stock exhaust is from the resonators a crimp in the pipes that is under 2" in diameter. If you really want to stay under $500, look on some other G8 forums and try to find a used RotoFab and a used Cortex tuner. You can then save up for a full catback exhaust and headers.

8UALIVE

iTrader: (2)

A tune would wake it up tremendously!! If u haven't got one already. I have a Vararam and I love it! No problems!! Congrats by the way!

JJhummus

If you plan on doing anything more than what you have done, nothing beats finding a good tuning shop or some online vendors that can retune the car. Waking up the tranny and other things will make the car much more enjoyable to drive and then when you add your goodies, the retune will give the max benefit. If you don't want to go that route initially, put an intake on it. The sound is nice and you don't have to worry about the exhaust developing a drone or being too loud.

BMW540-G8GT

Thanks guys. The tune is the #1 recommended first mod and the only reason I haven’t considered it is that I don’t want my b2b or GM drivetrain warranty to be compromised by a tune. It seems most are not worried about this, it seems you can flash the stock tune to the car before bringing it in for any work..... but it still worries me a bit. I can feel so much power in this car but it certainly isn’t there at the push of the throttle, at least not instantaneously and the tranny even is sport seems very slow and lazy, yet durable and strong.
So, if I decide a tune is what I want to do what do I look for? I am VERY limited in knowledge of tunes. My guess is that a local dyno tuner would be the best bet as tuning via dyno is probably going to net the best gains and it’s probably no more than $300 or so..... Will this kind of tune also address the transmission?
If I don’t have a local dyno tuner that can work on my car, what do I look for in tuning devices (cortex, diablo, etc, etc)?????
Thanks again!
The only reason I have the solo axle back in mind is because this stock exhaust is so quiet and I love the V8 rumble. I am thoroughly impressed by the power of this car but the quietness leaves something to be desired. The fact that it appears I can bolt it on and then bolt my stock exhaust back on for family trips is what is appealing to me. I am not planning on getting headers or a supercharger or anything major like that. I’m thinking cai, tune and axle back for the sound..... low 13’s or high 12’s sound fast enough for me ;-) ... for now.

XxXTransAmXxX

iTrader: (12)

Hello,
I am a Service Manager at a GM Dealer. Yes new guidelines state any major Powertrain Claim involved sending a screenshot of all Calibration ID's in the PCM/TCM prior to authorization of a major repair.

However as I did on my G8, I just bought a spare PCM to play with, thus keeping the PCM that's been in the car for use down the road should I have trouble with the vehicle for "Calibration ID proof"

Also tho TIS2WEB SPS (GM programming interface) does log all flashing/programming via VIN and DATE. So tech there is still a record of me flashing the new PCM somewhere on file.

The big thing as I try to help all of my customers as I am a mod guy myself. If you are loyal to your shop for repairs or just a loyal customer to them, they are more apt to help you out and stick their neck out vs a situation where you would show up as a "stranger" to the dept or company asking for assistance. Either way just be honest and up-front with the service manager on things 9 out of 10 times they will take care of you.

XxXTransAmXxX

iTrader: (12)

On a side note....

My G8 mods were as followed in this order;

1. Solo Axleback w/ J Pipes, Mid-Muffler Delete with X Pipe
2. Roto Fab CAI
3. Camaro SS wheels with Nitto Invos
4. Tint & Vinyl work
5. Cortex running the Perf 93 tune currently

I am completely happy with this car. I will only do Susp mods for now as it is just fine for my DD during the summer. As I park it next to the Firehawk in the winter when I drive the TBSS....

Check out G8Board for more info