CA Supra owners and cat back exhausts

[MZero1]

Good morning,

Can anyone in our wonderful Left coast state of CA chime in on installing a cat back exhaust and then getting your Supra smogged? I would love to get either an HKS or RK Titanium exhaust, simply for sound and looks (I understand no power gain without tune) but am reluctant due to the effen CARB restrictions. Apologies if this is elsewhere within the forum. I tried a search. thanks all!

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[PASupra85]

I live in PA, so take this with a grain of salt. We are required to follow CARB as well and my understanding is that as long as you are not touching the emissions part of the exhaust (cat) you should be fine for smog. HOWEVER, noise levels are a different story. I think the limit is 95dba in CA. That is where you might get into trouble.

 

[MZero1]

Thanks man, I have read about the sound level limits. My understanding is that the HKS is relatively quiet compared to others. I appreciate the response! BTW, I have family back there near Easton and have visited several times. Your roads are fantastic compared to pot hole ridden Norther CA. It's a shame Cal-Trans/state can't do same here.

 

[PASupra85]

Thanks man, I have read about the sound level limits. My understanding is that the HKS is relatively quiet compared to others. I appreciate the response! BTW, I have family back there near Easton and have visited several times. Your roads are fantastic compared to pot hole ridden Norther CA. It's a shame Cal-Trans/state can't do same here.

welcome! Easton isn’t too far from me; about 40 mins or so. Tbh… the roads are hit or miss… as in the potholes . it’s town by town and a lot of them are small around me so you can drive on a road that is silky smooth then enter the next town and need to swerve like you are on an autox course!!! All about local budgets I guess…. Not to mention the salt /brine that they use around me really beat up the roads. My daily looks like it has been through a salt field.

 

[adrian56k]

Once you get your car smogged you don't have to worry about it for years. I just got my car smogged and then immediately installed a catless downpipe and exhaust system after the car was registered. However, it is important to keep the stock components just in case you get into any trouble. Then you can easily replace the parts you need to pass a smog again if need be. Another option would be a hot smog.

 

[concept]

Good morning,

Can anyone in our wonderful Left coast state of CA chime in on installing a cat back exhaust and then getting your Supra smogged? I would love to get either an HKS or RK Titanium exhaust, simply for sound and looks (I understand no power gain without tune) but am reluctant due to the effen CARB restrictions. Apologies if this is elsewhere within the forum. I tried a search. thanks all!

I've had an aftermarket cat-back exhaust on a previous car for 12 years. As long as your cat remains, you should be good to go. Cat-backs have no adverse effects regarding emissions.

 

[MZero1]

Thanks all for the input. I shall move forward shortly and get a cat back for my baby.

 

[swrdply400mrelay]

I've heard the HKS dual muffler IRL, and to me it's really loud to where I can't tell the difference between valve open and closed

As others have said it doesn't affect CARB, but some areas the cops are more strict on sound violations.

Interested in seeing which one you get!

 

[Tsuki]

I've heard the HKS dual muffler IRL, and to me it's really loud to where I can't tell the difference between valve open and closed

As others have said it doesn't affect CARB, but some areas the cops are more strict on sound violations.

Interested in seeing which one you get!

Correct - if you want to stay within the sound limits, you do NOT want the dual-muffler HKS, you want the Super Turbo Muffler. The dual-muffler is actually past the legal noise limits in Japan, as well, so it does not have the certification needed to run on the streets there, but the Super Turbo does.

 

[Illest1Five]

HKS Super Turbo Muffler is less loud than the HKS Hi-Power. Super Turbo Muffler is slightly louder than stock. Both are cat-back so you won't have to worry about anything related to smog checks or CARB compliance as they don't alter emission parts.

Sound compliance is a different story. The difference between you getting an exhaust ticket or not is subjective - you're at the mercy of law enforcement who thinks you are below/above 95db limit. Your saving grace could be CA State Ref paperwork that certifies your exhaust is sub-95db but that's a tedious process that requires you to have received an exhaust ticket, get sound tested at a CA State Ref, and passing sound test.

 

[concept]

HKS Super Turbo Muffler is less loud than the HKS Hi-Power. Super Turbo Muffler is slightly louder than stock. Both are cat-back so you won't have to worry about anything related to smog checks or CARB compliance as they don't alter emission parts.

Sound compliance is a different story. The difference between you getting an exhaust ticket or not is subjective - you're at the mercy of law enforcement who thinks you are below/above 95db limit. Your saving grace could be CA State Ref paperwork that certifies your exhaust is sub-95db but that's a tedious process that requires you to have received an exhaust ticket, get sound tested at a CA State Ref, and passing sound test.

Most people know this but always be aware of your surroundings before accelerating "briskly" (city or highway) with an aggressive exhaust system. It used to be difficult at times when I lived in Conn, as there were cops in plain-looking sedans who would hit their flash-alternating high beams as they chased the "perpetrators".
Here on the west coast, this is far less likely to happen.

 

[MZero1]

I've heard the HKS dual muffler IRL, and to me it's really loud to where I can't tell the difference between valve open and closed

As others have said it doesn't affect CARB, but some areas the cops are more strict on sound violations.

Interested in seeing which one you get!

Thanks! Leaning toward HKS, poss SuperTurbo model. Would love a titanium system though.

 

[MZero1]

Thanks all,

Kinda related, does anyone use Race Ramps "wrap" ramps? Expensive alternative to floor jacks and stands but looks safer and provides 14" of work space for DIY guys. Which I want to try to do my own exhaust swap.

 

[SupraTR]

Thanks all,

Kinda related, does anyone use Race Ramps "wrap" ramps? Expensive alternative to floor jacks and stands but looks safer and provides 14" of work space for DIY guys. Which I want to try to do my own exhaust swap.

Given the price for these ramps (I did a quick google so maybe the product you're thinking is cheaper elsewhere) I'd just get yourself a Quickjack. A bunch of members on the forum have one and I can tell you its 100% worth it and will provide even more space. Stores very easily in the garage. I think I got mine on sale for ~$1200-1300.

 

[MZero1]

Does the quick jack contact points do any damage to the "BMW" plastic mounts?

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