Straight pipe-removing mufflers?

Does straight piping really do much for performance?

How much loader would it be?

1968 302 4 brl

Does a cross over do much?

Removing the mufflers makes them sound like crap unless you have a race engine. The drone will give you a head ache. Same with before axle turn downs

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This was the first modification my 16 year old self did with my first Cougar. It sounded great for the first half mile. I went past my girl friends house. Her father, who was a serious car guy told her she wasn’t getting in that car until I got the muffler fixed.

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I chopped off my '68’s exhaust when I was young too. It was because I backed into a steep uphill driveway and smashed the old single exhaust. I drove around for a little while with no muffler and thought it was badass at the time. But it’s very loud and would get old quick, not to mention the potential for unwanted attention from the local constabulary. Shortly after, I got a set of dual, long glasspacks installed with an H-pipe. This setup is still on the car and I like it.

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I never ran straight pipes, but I did have some glasspacks bolted directly to a pair of Blackjack Aluma-Kote headers for a while. The rest of the engine was pretty mild; just a stock headed 302 with an Edelbrock Performer intake and Autolite 4100 on it.

It was loud enough to break the sound barrier just starting the car. Goosing the throttle would give you tinnitus. Not even kidding.

If you have the old cast iron log manifolds, it would be a little quieter than the header/glasspack solution I tried, but not by much, and it really won’t sound racy - just trashy and annoying. Nice for a demolition derby car maybe, but not so much for a Cougar, especially if you want to drive it on the highway.

Any crossover will usually gain you a percent, maybe two percent more horsepower. Not a huge deal. It does change the sound just a bit too. You won’t notice a performance boost, but without it, there will be a much more pronounced left-right burble when you stand behind your car. H pipe smooths that out just a little, but retains most of the same note. An X-pipe smooths out the sound considerably, but offers virtually the same performance as an H pipe.

My car is nearly straight piped. It has glass packs that I’m sure my dad poured oil in to burn them out. It’s loud, sound is meh, volume is loud. It drones on the highway, but not unbearably so. Now that I’ve been driving it for a couple years, I’m ready for mufflers.

It’s worth noting that with any type of muffler, the smaller the louder. And vice versa. My dad had HUGE glasspacks on his '72 Cadillac Eldorado, and even with 500 CID, it was very mellow and quiet except at full throttle. No drone at all.

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Highly suggest mufflers. You can control the sound level quite a bit depending on what kind of muffler you have. Personally I avoid glasspacks, I hate how they sound but many do and they are cheap.

Avoid turn downs too if you can. I have turn downs at the axle as a temp solution but hate it. A good quality set of mufflers and tailpipes will do wonders.

This is all very helpful!! I appreciate the suggestions, advice and real life experiance.

Going to stick with muffler, add crossover, and remove downturns.

Ill post a before and after video once done for all ya’all to see the results.

Might be a while, If I ever get drug tested, one drug they can save money on testing for is SPEED, I am not the fastest at “git r dun”.

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Yep exactly, my glasspacks are quite long, and sound pretty mellow. Nothing like the obnoxious little popcorn machines that some may be thinking of.

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