Hi everyone,

I have an 87 LT with a 92 Z28 TPI 305 in it. Right now the car has stock manifold, stock y-pipe, and I believe stock catalytic converter(bought the car a few years ago, most all work was done by previous owner, I don't know all of the specifics). The guy who had the car before me put on a dynomax cat-back exhaust. Now the car sounds good, I love the tone, but I want it to be a bit louder. My thinking is to get shorty headers, aftermarket y-pipe, and high flow converter. Now will those upgrades make my car louder, or will it not make a noticeable difference. I just want to make sure it actually will make my car louder. If this wont make a difference what other alternatives do I have? (other than long tubes, can't really afford them)

Also, I do not care much about improving performance, its a stock 305 with a slight tune and MSD ignition. Headers wont make it into a 13 second car, but I am just looking for sound.

I really appreciate the help
Best Regards,
Cat

 

JUST CHANGE OUT THE MUFFLER TO CHANGE OUT THE SOUND
IT IS CHEAPEST THING AND IF YOU ARE NOT LOOKING FOR PERFORMANCE UPGRADES, WHY SPEND MORE MONEY THAN YOU NEED TO?

 

Thanks for the input!

Well I looked up magnflow's muffler, and from the videos on youtube, the mufflers doesn't sound much different than my dynomax, so I am not gonna bother to buy a new muffler.

Now back to my original question, will the shorty headers/y-pipe/hi-flow converter make the car louder? Also if I do get these upgrades, how much power can I expect to gain, if any?

Thanks again,
Cat

 

If you don't have emissions testing in your area then I would get rid of the
cat.I have a flowmaster with 3 inch piping and when I got rid of the cat I heard a very noticeable change.that's if you are looking for a cheap alternative.

 

Cheapest and quickest way (also illegal in some places w/ emissions testing) is to gut the cat. Open it up, take all the insides out, and put it back in. You can also get a cat delete pipe that just replaces it, but I just gutted mine.

As for general sound, the further back you get from the "road" (exit) side of the exhaust, the less it does for sound, but the more it does for performance, especially in these cars. Mufflers are sometimes expensive but are by far the most effective way to get more sound. Headers and a y-pipe will make noticeable difference when you step on the gas, and you might have more rumble at idle, but in my experience, it doesn't do nearly as much as a cat-back or muffler.

Bottom line, if you already have a 3" system, I would gut the cat, see how it sounds, and then buy a new muffler if you want.

 

I personally don't feel comfortable gutting the cat, even though my car just got through its last emission test (in P.A. cars 25 years or older are exempt). Somewhere I read it is a pretty serious crime if caught, even though I would most likely never get caught.

Well as it seems, from the information you guys have gave me, headers won't do much for sound. I guess if I really wanted more sound I would have to do long tubes and fab up an dual exhaust(not in my budget ), but now that I think of it, if I can feel some more power in the car, it may be worth it.......I guess for 450 bucks for the setup I am looking at putting together is a pretty good deal.......now a few more mesially pay checks and I order...........

Thanks to everyone for their help, when I actually do this I will post a before and after vid

 

What set up are you looking at ? A 3in. Cat back ?

 

my 305 has edlebrok headers cat delete,and magnaflow muffler,and its sounds nice at idle and has alot of grunt from there up

 

I already have the Dynomax cat-back on it(I believe it is a 2.5 inch, but I have to measure it). I am looking at getting the Hedman shorty headers, their y-pipe, and a magnaflow universal converter from summit. But there are a few unknowns I need to figure out first. My car does not have AIR tubes on the manifolds, the only thing hooked up to them is the O2 sensor, now will these headers come with a place to put in a O2 sensor, or do I have to fab something up. Also the converter on the car now has a tube that comes out of the shell, but it is not hooked up to anything, do I need a converter that also has the same thing?

Thanks

 

If you don't have AIR, then that tube on the cat should be welded up, and the cat gutted otherwise it will not function properly and/or fail. You could always get a non-air CAT, which is what I did and am installing in a few days.

My current setup is: Edelbrock headers and y-pipe, stock gutted cat, 3" flowmaster cat-back.

It's really loud, great rumble at idle. I have a 305 with alot of upgrades tho (cam, forged internals, ported and polished heads, TPI intake done over as well, etc.)

 

you'll need a bung installed on the drivers side header

be careful where you put it so it has clearance and isn't in the way of the oil filter either. You'll figure it out as you hold it up for fitment. ( that was my way of saying don't panic and ask for suggestions because it's best to be seen with your own 2 eyeballs)

 

I had an 80 series Flowmaster on my otherwise stock LG4 305. Sounded great and was pretty loud. Much more bark than bite with an LG4 lol.

 

Just put on the Flowmaster CAT back 3" exhaust with the 80 series muffler. Looking to add a "off-road" 3" Y-pipe. With no CAT will the car go into a safe or limp mode? Do you need a custom tune?

 

Just run open manifolds like all the trashy trucks! Haha jk but seriously on my ol 305 I ran no cat to a Flowmaster 80. Still pretty trashy imo but sounded sexy so I didn't care at all.

 

Does running an off-road Y pipe require a custom tune or MIL eliminators? I had an 03 Mach 1 and had to get a custom tune or the car would go into a safe/limp mode since the back O2 sensor was reading the same value as the front O2 sensor.