Fast Intentions CBE Review
 

I’ve had my Fast Intentions CBE installed for a month now, so time for a review… I have the 18” resonators with stainless steel mufflers. Everything else is stock on the intake/exhaust. Also keep in mind this is on a Roadster, which has different acoustic properties since it has top storage and a separate trunk vs. the open hatch area.

PROS:
• Great engine start up sound; compared to stock it is louder, lower frequency, and still refined IMO; cold start is a bit loud, but once the RPMs drop to normal range it mellows out
• Overall sound quality is exactly what I wanted, it has burble, it cracks/pops beautifully during a downshift throttle blip; cracks/pops even occur occasionally during up shift depending on throttle position and gear; this is probably my favorite attribute from sound standpoint
• Overall volume drops almost to stock level at idle (once engine is warmed up), and when cruising with little/no load or throttle input (ex. 75 mph highway cruising in 6th gear)
• Power increase is easily recognized by the butt dyno; most noticeable at greater than 3,000 RPM and with cold ambient temperatures it seems even more prevalent; I believe 20 whp all day long, but keep in mind it’s an upper RPM range power increase; it pulls harder, more response to throttle input in this range
• Great looking exhaust; I was concerned I’d hate seeing the mufflers from a rear view but I am really happy with how they look; tips fit good to the bumper with some washers on the rear hangers (they were too close to bumper without spacers)

CONS:
• Left side exhaust tip sits about 1/8 inch further car forward than right side, but only noticeable from certain angles, not a big deal; I couldn’t adjust this
• Some may consider cold start noise level too much (low frequency, pressure on ears), but again it settles down as the RPM drop to normal idle
• Reduction in throttle response/power at < 3,000 RPM; this was surprising to me as I thought the power increase would be across the RPM range or at least not reduced at low RPM; this seems to be worse at high ambient temperatures (> 80 deg F); at low ambient temperatures it feels basically same as stock; it’s not a deal breaker, but I think it’s something people need to consider before buying; it is noticeable change from stock condition
• Drone with small throttle tip in at 2000-3000 RPM range, mainly 5th/6th gear; example… driving around town at 40-45 mph in 5th gear and you tip into throttle for small acceleration, you get a low frequency drone/pressure in ears; again this isn’t a deal breaker, if you shift to 4th gear in this situation to get RPM > 3,000 it goes away. A lot of reviews I’ve read say no drone on the FI exhaust, but that is not true IMO. There is some drone in this range, but I do not think it outweighs how great it sounds everywhere else in the RPM range

Overall, I love the system! This was my first performance mod I’ve ever done (I mainly leased vehicles prior to the Z). The overall sound, the power increase at higher RPM, and the high quality appearance make it money well spent. I’d do it again in a heartbeat. Thanks to FI for developing this excellent system!:tiphat:

One question I have, would an intake modification improve the < 3,000 RPM throttle response / power? It seems that the lower back pressure from the FI exhaust is the cause, so I’m wondering if opening up the intake a bit will balance it out?? Maybe a dumb question.

http://i191.photobucket.com/albums/z...r/IMG_1448.jpg

Not a dumb question, shows you're thinking.

An intake would make the low-end response even worse. Opening up the car's breathing system will result in top end gains and low end losses until you get a tune. A tune will tell the car's brain how to compensate for the lack of pressure at low RPM and get you a skosh more power.

You should definitely look into getting a tune to take care of the loss at the bottom of the tach.

Do you plan on doing any other bolt ons? If so, hold off on the tune until you have done everything.

Nice review!

I have checked my Z with FI exhaust on dyno few times . With this exhaust there is about 7WHP gain over 6000rpm, no difference 2500-6000rpm and signifcant loss of WHP and TQ below 2500rpm. There is no way to 100% reduce this loss even with tune. If you will install eg. HFC it will be even worse due to reduce of back pressure.

Well, after a tune it will get "louder" in the sense that, less back-pressure, but a smoother deeper note due to better airflow? But then again thats what I feel what happened when I got the Tune on mine.

Review is on point.

Having the same exhaust as OP, I can pretty much confirm everything here. Getting on the gas at a low RPM/higher gear will produce a slight "drone" however a quick downshift takes care of it.

Thanks for the feedback guys. I honestly had no idea a tune would be required to maintain stock HP/torque at low RPM with this system. I have been throwing around the idea of the Stillen Gen 3 intake or the Z1 intake, but I wouldn't like having to remove the front bumper to clean/replace filters. The other idea was AAM dry filters and the Z1 post-MAF silicone tubes. I suppose I could look into getting a tune after that, but it wasn't something I planned on doing! The other problem is I don't think there are any tuners anywhere near Detroit.

Where/what kind of tune did you get? Ecutek? How do you think the throttle response / power below 3,000 RPM changed after tune? Your set up (FI exhaust + Z1 MAF & Drop Ins) is what I would probably do. Thanks!

A tune isn't technically "required" if you are ok with how the car is performing with just the exhaust. If your plan is to optimize the mods (exhaust, intake, HFC, etc), then a tune is highly recommended. The Stillen G3 will net you good gains in the upper RPM range (where our car's make the most power). I personally went with HPS Tubes + K&N Filters since I'm not that interested in upper gains as much as a smoother rev range.

I got EcuTek done by Nik @ Soho (Link: http://www.the370z.com/tuning/109482...ml#post3439636). The Tune is awesome. Throttle response is much much better over 3k, and under is much improved. There is no more "lag", besides from heatsoak which happens periodically as it is blistering hot in NC.

I would def recommend getting a tune AFTER all the mods. I kinda wish i would've done FI 12 Stainless + Berk HFC, I'd have a slightly higher curve midrange.

Great review GOBLUE and we appreciate your honesty. I'm glad that you love the system over all, we do our best to offer the highest quality products on the market.

Our 18" resonated exhaust system offers the best of both worlds. It produces a deep, smooth exhaust note that really comes to life under wide open throttle. While at cruising speed the 18" resonators really help to minimize added interior noise. I know this was a concern being your car is a roadster.

The design of our exhaust system is very modular, this allow for a lot of adjust-ability when aligning the exhaust tips. Exhaust tip alignment can take a little work and sometimes requires a second set of hands (from a friend). If you need help lining things up, give me a call and I'll give you a few pointers over the phone.

I'm surprised to hear that you noticed a lack of throttle response in the sub-3,000 RPM range. All of our dyno testing shows that no performance was sacrificed down low, and in the high RPM range is where these cars really come to life.

As for an intake system, these will help yield more peak power gains. A tune will help your throttle response. Normally I'd recommend tuning once you've completed the 3 breathing modifications (intakes / cats / cat back exhaust). A good tune will help maximize the performance benefits of your modifications.

If you have any questions, please don't hesitate to ask.

Thank you,

- Kevin

Thanks!

Dyno testing at WOT probably won't show a performance hit experienced at partial throttle down low. Then again, it might be OP's head playing tricks on him and not pressing the pedal down as much since it's louder now.