HP/Torque gains on HFC with invidia exhaust

Daravelli

Member
Car
2011 Fx35
Hi guys,

I did a search and didn't see this specific question answered, but if it has been my apologies.

So, the invidia exhaust on a 2nd gen adds roughly 16hp and 20 torque according to the dyno test by the manufacturer. Any data (either estimated or dyno tested) on how much hp/torque high flow cats add in addition to this figure?

Also, my local shop quoted me $900 tuning costs ($300 license fee for Uprev, $600 tune) and $500 labor for an invidia exhaust and test pipe w/ HFC installation. Does this seem really high to anyone else, or is that typical? I didn't think a bolt on exhaust installation was very labor intensive, but I'm no mechanic.

Thanks all.
 
In my opinion, the custom tune is a bit high. The exhaust installation is way too high. But cost is relative though. I would ask a couple other muffler shop for comparison.
 
Tune price seems high, it varies by location, but most custom tunes are in the $5-600 range. Denver doesn't seem like it would have so few options that they could charge that much. Most shops charge ~$100 per hour for tuning, it doesn't take 6 hours to tune a car with just an exhaust.

Exhaust labor is ridiculous. It's maybe a 3 hour job for HFC and catback install, probably less if the shop is competent. I bet if you called a muffler shop, they'd do it for half of that. "Performance" shops are typically a ripoff when it comes to basic stuff like exhausts. They charge you their going rate of $100-150 an hour for work when really the work is the same as a muffler shop charging $50 an hour.

FWIW, an exhaust isn't going to give you 16-20 hp by itself. There isn't that much restriction in the OEM system. Maybe 16-20 all in with the HFCs and exhaust. And you can't run test pipes with HFCs - one or the other.
 
Tune price is high and so is the install. Even with a $150/hr shop time, it shouldn't take more than 1 hr to install an exhaust, maybe 1.5hr tops to put on the HFC also if some of the bolts are rusty.

My Uprev tune was $600 with the license.


...as for the power gains, with a TUNE you will get maybe 15HP from the HFC, and maybe 5-10hp from the rest of the exhaust. I wouldn't expect more than a 25hp jump tbh.

Make sure they run a base line before install, then tune it for the power. Then you can see how much you really gained....

Good luck
 
In my opinion, the custom tune is a bit high. The exhaust installation is way too high. But cost is relative though. I would ask a couple other muffler shop for comparison.

Tune price seems high, it varies by location, but most custom tunes are in the $5-600 range. Denver doesn't seem like it would have so few options that they could charge that much. Most shops charge ~$100 per hour for tuning, it doesn't take 6 hours to tune a car with just an exhaust.

Exhaust labor is ridiculous. It's maybe a 3 hour job for HFC and catback install, probably less if the shop is competent. I bet if you called a muffler shop, they'd do it for half of that. "Performance" shops are typically a ripoff when it comes to basic stuff like exhausts. They charge you their going rate of $100-150 an hour for work when really the work is the same as a muffler shop charging $50 an hour.

FWIW, an exhaust isn't going to give you 16-20 hp by itself. There isn't that much restriction in the OEM system. Maybe 16-20 all in with the HFCs and exhaust. And you can't run test pipes with HFCs - one or the other.

Tune price is high and so is the install. Even with a $150/hr shop time, it shouldn't take more than 1 hr to install an exhaust, maybe 1.5hr tops to put on the HFC also if some of the bolts are rusty.

My Uprev tune was $600 with the license.


...as for the power gains, with a TUNE you will get maybe 15HP from the HFC, and maybe 5-10hp from the rest of the exhaust. I wouldn't expect more than a 25hp jump tbh.

Make sure they run a base line before install, then tune it for the power. Then you can see how much you really gained....

Good luck

Thanks guys, this is in line with my thoughts. These guys are closest to where I live and work, but looks like I need to take a look around and find something more reasonable. A muffler shop or even just a non-performance shop is probably a better idea for the install itself.

Is it safe to drive after the exhaust install before tuning, or do I actually need to have it towed to the performance shop for the tune immediately after install? I've read through a thread and it seemed like there were people going both ways on the subject...
 
No no need to have a tune for installing new aftermarket exhaust. I won't hurt anything without a tune.
 
There is no bolt on for the FX that requires a tune to drive. A tune would optimize things, but you could drive indefinitely without tuning, the ECU will compensate. Only thing that would require tuning to drive is larger injectors or MAF, pretty much anything short of that is driveable without tuning.
 
guys im dying to do the high flow cats done before i get the uprev tune so i dont have to retune my car..... but CA emissions and sniffers on the on ramps... anyone with hfc have any issues with the smell? and will they pass the sniffer test?


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guys im dying to do the high flow cats done before i get the uprev tune so i dont have to retune my car..... but CA emissions and sniffers on the on ramps... anyone with hfc have any issues with the smell? and will they pass the sniffer test?


Sent from my iPhone

HFC should pass but depends on brand etc find one that shows data proving it will pass aka they say "California legal" or something....
 
HFC should pass but depends on brand etc find one that shows data proving it will pass aka they say "California legal" or something....

I'd be interested in hearing from peeps with HFC and aftermarket exhaust that have passed emissions with no issues. I'm in CO so not the strict standards of CA, but it would be good to know which brands have passed in any state really. I do remember reading a thread on here where the guy was using kinetix HFC and it passed emissions fine, but I don't remember what state he was in.
 
HFC should pass but depends on brand etc find one that shows data proving it will pass aka they say "California legal" or something....

there are no high flow cats in the world that state that they will pass CA smog. as long as they pass sniffer then i will be good. i was looking at the cnt racing hfc


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I'd be interested in hearing from peeps with HFC and aftermarket exhaust that have passed emissions with no issues. I'm in CO so not the strict standards of CA, but it would be good to know which brands have passed in any state really. I do remember reading a thread on here where the guy was using kinetix HFC and it passed emissions fine, but I don't remember what state he was in.

I have passed in NY with Kinetix HFC on my first gen. You have to make sure the 02 sensors are set off from the main piping with either spacers or a J pipe.


there are no high flow cats in the world that state that they will pass CA smog. as long as they pass sniffer then i will be good. i was looking at the cnt racing hfc


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The issue is that although a lot of aftermarket cars WILL PASS the sniff - they will not be able to get a CARB number so technically they are still illegal.

My comment was a bit of a tongue-in-cheek comment..

many people run aftermarket parts on their cars.

For example Kinetix claims their HFC are "SMOG legal" and do meet all Federal/EPA rules, and will pass emissions, but states they do not have a CARB number. Some have claimed that the inspection stations are OK with certain brands because they are known to meet all the fed/EPA rules...... (seen on another forum)

Also, you can always just swap the stock ones back in for the inspection. Exhaust parts aren't permanent ;)
 
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Any update on the HFC + tune combo? I don't want a full exhaust and don't want test pipes. But filters/MAF-tubes, pulley, HFC, and a tune may be a decent setup.
 
Any update on the HFC + tune combo? I don't want a full exhaust and don't want test pipes. But filters/MAF-tubes, pulley, HFC, and a tune may be a decent setup.

i got invidia HFCs and Invidia Gemini with Stillen gen 3 on my 2nd gen. My gaskets in the catback are leaking a bit but with the HFCs there is a noticable loss in low end torque. Because the 7speed likes to upshift into a high gear in D and never downshift I really feel the torque loss. I am going to get tuned as soon as I fix my leak. But for sure when i put it in first and floor it from a dig theres more wheelspin for sure. Really likes to rev out now.
 
Thanks for the feedback! Low end torque is what I desire the most, so it sounds like there's next to nothing to enhance that. Oh well, motor will likely stay essentially stock.
 
Thanks for the feedback! Low end torque is what I desire the most, so it sounds like there's next to nothing to enhance that. Oh well, motor will likely stay essentially stock.
Look for differential with a higher multiplier number like a 330 could become a 3.69 maybe a 411
 
What's the benefits on a differential like that ?

You get better low end punch... 3.3 gears (stock Final Drive on the FX35 RWD) are like highway gears. going up to a 3.69 (g37s) final drive or even 4.11 or 4.3 will give better off the line. Plus they come as VLSDs


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You get better low end punch... 3.3 gears (stock Final Drive on the FX35 RWD) are like highway gears. going up to a 3.69 (g37s) final drive or even 4.11 or 4.3 will give better off the line. Plus they come as VLSDs


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Now that's what I'm talking about. Do you know a part number?
 
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