was also thinking of getting rid of my mac catback and going with magnaflows since its a straight through muffler. Not sure if that will make a difference. Any opinions would be appreciate guys.
3 inch catback
- Thread starter stangfreak
- Start date
Here’s an 800 rwhp cobra with a flowmaster cat back. At the end they unbolt the cat back and dyno it with an open x pipe. It only gained 5 hp and 7 torques. They’re not really choking up the exhaust. Also, my buddy’s 2.9 whipple cobra went bottom 10’s at 140 with flowmasters. I’d run what you like sound wise.
Yes that is what I was expecting. Its funny you mentioned the flowmasters. Back in the day when snakebite was sold, the car had a 3.4 whipple built motor and a custom 3 inch exhaust. I forgot who did the custom exhaust. But it was big boy stuff.
Not sure if you remember venomous03cobra. He is a very good friend of mine. One of the best drivers I have ever seen. John also built his motor from the same place, had a 2.8H kenne bell with off the shelf exhaust. Nothing like snakebite. Just regular exhaust. I dont even think he had 1 7/8 long tubes. Nothing was 3 inches. If I remember correctly. Both cars made the same power. Granted, the new snakebite had a 3.4 whipple but NON CRUSHER.
when venomous had the stock motor and again just a simple exhaust setup, he ran 10.32 at 134 with a ported eaton and a 60 dry shot.
I just wanted to see if any of you had different experiences.
When I was ordering my ARH midpipe, they told me they didn’t see any significant restriction or power gain on 2 1/2 vs 3” until some ridiculous number.
Any time a company tells me not to bother with a more expensive part, I believe them
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Makes me want Super 44s again...Greatest sounding muffler behind the Borla Stinger. In my opinion, of course...
nick told me the same thing. Thats why I didnt bother getting a 3 inch exhaust.
I have 44’s in my magnaflow cat back. I prefer chambered mufflers. Less raspy than a straight through.
I’ve ran 2.5” magnaflow catback at 900whp turbo with no issues on a 5.4 no less. I think an sc 4.6-5.0 with a 3.0 whipple will be ok at 900-1000whp without much if any restriction. The big key will be muffler design and where the x is, high flow or no cat etc. If it makes great healthy power on a 2.5” setup stick with it because ground clearance sucks with a 3” catpipe. I think you have to get something oval bent or it’ll just have to sit higher/ruin the stance like I have had to come to terms with.
Now I did 3” resonators and straight piped… But I’m on a bigger pair of turbo’s setup with 1/5/8-3” headers, 3” x pipe. On 20-30psi it jumps above 1100-1200whp so I have the 3” side for that but if I was running just pump gas or booster, 10-12psi, the 2.5” should have been fine.
I recommend at least a great resonator for any test pipe setups, it softened the car by 50% volume but cleaned it up by 200%. I didn’t want a resonator and run header back castles for a week, but it was raspy and pitchy. Put the 3” bullet resonators in and it’s like almost perfect to me now.
Turbo/sc play totally different but you gotta realize a turbo car hates exhaust restriction where an sc car just pushes that crap out regardless
Open header, dumped under the car vs through the resonators and tailpipes, I pick up less than 25whp turbo and all with high boost.
Run what sounds great, you can’t feel 5-25whp at 800whp or higher. The car will vary 50whp just with weather and engine temp conditions at that power level.
Now I did 3” resonators and straight piped… But I’m on a bigger pair of turbo’s setup with 1/5/8-3” headers, 3” x pipe. On 20-30psi it jumps above 1100-1200whp so I have the 3” side for that but if I was running just pump gas or booster, 10-12psi, the 2.5” should have been fine.
I recommend at least a great resonator for any test pipe setups, it softened the car by 50% volume but cleaned it up by 200%. I didn’t want a resonator and run header back castles for a week, but it was raspy and pitchy. Put the 3” bullet resonators in and it’s like almost perfect to me now.
Turbo/sc play totally different but you gotta realize a turbo car hates exhaust restriction where an sc car just pushes that crap out regardless
Open header, dumped under the car vs through the resonators and tailpipes, I pick up less than 25whp turbo and all with high boost.
Run what sounds great, you can’t feel 5-25whp at 800whp or higher. The car will vary 50whp just with weather and engine temp conditions at that power level.
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