adding headers and exhaust to cutty

[86_olds]

if i add some hooker headers to my cutty and a flowmaster exhaust and just tune it up all legit like take it to muffler shop ..will it still pass smog if everything is running good or will adding that make it fail smog??

 

[FE3X CLONE]

What engine?

There are no smog legal headers for an Olds engine to my knowledge.

Are you going to true duals? If so, that's technically illegal according to the letter of the law.

 

[86_olds]

stock 307 v8 umm no true duals for now was just going for single with a new cat cuz the one thats on is making a leaky sound

 

[FE3X CLONE]

Well, the problem is that with headers, you don't have any way to run a single exhaust.

Your best bet for stock 307 would be to use a cat-back dual exhaust. It remains emissions legal and you don't have to mess with anything forward of the catalytic converter.

 

[DrRansom442]

Single exhuast can be made to run off of headers .... however as stated. If you live in an area that smog tests. This will NOT be legal. If you follow the exact text of the law. You can not modify the federally certified emmissions package .... i.e. no modifications to cat location ... modifications to "y-pipe" (which gets fuzzy since 307 exhaust dumps one manifold into the other and does have a "Y-pipe" to speak of. I tied my headers into the exhaust behind my cat-converter (when I eliminated it), but my car isn't emmission compliant by ANY means. Check local laws. You maybe reserved to cat-back only mods.

Given that you said a stock 307 ... I honestly don't think you will see gains from running headers. 307 heads aren't known for flow numbers. On my 87 I ran cat-back mods. I had a mandrel bent tube ran into a Camaro style Flowmaster and had dual exitting tail pipes in the factory locations. IMHO it sounded even better than the O.E.M. 442 style exhuast and often got looks and inquiries as to "what's under the hood?" - "just a bone stock 307 with a K&N air filter and exhaust".

 

[FE3X CLONE]

Single exhuast can be made to run off of headers .... however as stated.

How do you get the pipe from the drivers side header over to the passenger side? With the transmission in the way, the only place to do it would to run it past the crossmember and join it up after the transmission.

If you ran a set of shorty headers like the Hedman 58160's then you could make a single exhaust work really well and look pretty much factory. However they'd still be illegal. It would just depend on where you live and how keen the tester is.

 

[DrRansom442]

Well the #4 heads on a '78 block and a total lack of emmissions components already makes my car non-compliant and I am just going to find an under-counter safety inspection. 81 cars do not have to run emmissions testing (cars 25 and older are exempt) but there is a visual inspection as part of the bi-annual "safety". Since the cat was removed completely, my exhuast shop was able to create a Y-pipe further back. I really need to get the car up on a lift and take some photos .... you realyl can not tell how the Y is made from my photos

http://www.facebook.com/photo.php?pid=1 ... 1682660462

you can clearly make out the passanger side collector and can see the driver's side pipe running back past the trans

http://www.facebook.com/photo.php?pid=3 ... 1682660462

this is the "Y" ... kinda wished I gota tad further under the car or had it on a lift

http://www.facebook.com/photo.php?pid=3 ... 1682660462

this last photo you can see where they tied the head pipe into the existing pipie into the (again) Camaro style muffler with dual tailpipes exitting

http://www.facebook.com/photo.php?pid=3 ... 1682660462

yup those are a 2nd hand set of Hedmann's

 

[78 salon]

Single exhuast can be made to run off of headers .... however as stated.

How do you get the pipe from the drivers side header over to the passenger side? With the transmission in the way, the only place to do it would to run it past the crossmember and join it up after the transmission.

If you ran a set of shorty headers like the Hedman 58160's then you could make a single exhaust work really well and look pretty much factory. However they'd still be illegal. It would just depend on where you live and how keen the tester is.

I've seen a pic of it done. It's funky looking, but here's how...From the driver side header, it does a 180* turn back to the front of the car. When it gets to the space where the factory crosover goes, it makes a turn into there, goes across the car to the passenger side and ties into the cat. con. As I said, it sounds funky and looks even stranger but you get to run headers and be compliant at the same time.

 

[FE3X CLONE]

quote] I've seen a pic of it done. It's funky looking, but here's how...From the driver side header, it does a 180* turn back to the front of the car. When it gets to the space where the factory crosover goes, it makes a turn into there, goes across the car to the passenger side and ties into the cat. con. As I said, it sounds funky and looks even stranger but you get to run headers and be compliant at the same time.

The problem is that's technically not compliant. All that gets you is the abilty to say the converter is in the same place. But you've modified the exhaust system ahead of the converter and is illegal according to the letter of the law.

Of course I don't want to sound like the emissions police guy because I'm definitely not on that end of the spectrum. Just don't want to see someone spend a bunch of money modifying their exhaust and not be able to get it past the emissions police.

 

[DrRansom442]

I'd have rethought things a tad, had I known there was a visual inspection. By all means check local laws or find some place that does under the counter inspections.