I'm getting close to finally making a decision about this exhaust I want to build out.I just installed some long tube headers and I definitely want to go two into one.
But I wonder... if you join the two into a single pipe, and then into a single inlet for a 1 in, 1 out muffler, do you lose the benefits you see in regard to better airflow, than if you go into 2 inlets into the muffler?
I really like these Magnaflow mufflers but It one comes with a one in, one out configuration. Otherwise, I'll prob go with Flowmaster 40, which has two in, one out.
Two into One Exhaust
- ZOSO
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Re: Two into One Exhaust
laffycaffi wrote:I'm getting close to finally making a decision about this exhaust I want to build out.I just installed some long tube headers and I definitely want to go two into one.
But I wonder... if you join the two into a single pipe, and then into a single inlet for a 1 in, 1 out muffler, do you lose the benefits you see in regard to better airflow, than if you go into 2 inlets into the muffler?
I really like these Magnaflow mufflers but It one comes with a one in, one out configuration. Otherwise, I'll prob go with Flowmaster 40, which has two in, one out.
Magnaflow makes a dual/single muffler. The magnaflows are reversible so it can be single in dual out or dual in single out.
Rob
74 Ranger EFI351w, 4r70w, ARB 5.13 9in, ARB 5.13D44, and a bunch of other goodies. Best of all the family memories.
04 Mustang Cobra, KenneBell 2.2 feeding a lot of boost on E85. Tire shredding machine
New project: 77 Bronco Ranger, body work and more body work.
Very little left of a 72 durango tan explorer sport
74 Ranger EFI351w, 4r70w, ARB 5.13 9in, ARB 5.13D44, and a bunch of other goodies. Best of all the family memories.
04 Mustang Cobra, KenneBell 2.2 feeding a lot of boost on E85. Tire shredding machine
New project: 77 Bronco Ranger, body work and more body work.
Very little left of a 72 durango tan explorer sport
- laffycaffi
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Re: Two into One Exhaust
You've answered my question, then!
- Digger
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Re: Two into One Exhaust
Don't get too hug up on performances losses. Most aftermarket exhaust systems are oversized for the average engine's performance.
I ran 2-1 exhaust, 2.5" diameter all the way with a decent 351W. Never felt like it was missing anything over the 3" exhaust it had prior.
Remember Bronco's are really short too and piping restrictions are a function of length/diameter, so a smaller diameter pipe over a short run will have comparable restriction to a larger diameter over a long run. If you have long tube headers, the 2-1 collector will likey be behind the t-case, the single exhaust from the collector to exit will only be 4-5 ft.
https://blog.tdotperformance.ca/guides/exhaust-back-pressure-how-to-choose-the-correct-exhaust-pipe-diameter/amp/
I ran 2-1 exhaust, 2.5" diameter all the way with a decent 351W. Never felt like it was missing anything over the 3" exhaust it had prior.
Remember Bronco's are really short too and piping restrictions are a function of length/diameter, so a smaller diameter pipe over a short run will have comparable restriction to a larger diameter over a long run. If you have long tube headers, the 2-1 collector will likey be behind the t-case, the single exhaust from the collector to exit will only be 4-5 ft.
https://blog.tdotperformance.ca/guides/exhaust-back-pressure-how-to-choose-the-correct-exhaust-pipe-diameter/amp/
Cummins R2.8 diesel, ZF5, AtlasII, HP44/BB9, ARBs, coiled / linked suspension, 37" KO2s, full cage, bumpers, etc.
Build Thread: http://www.coloradoclassicbroncos.com/viewtopic.php?f=3&t=5420
Average 23.5 mpg, Best tank: 26.3 mpg
Build Thread: http://www.coloradoclassicbroncos.com/viewtopic.php?f=3&t=5420
Average 23.5 mpg, Best tank: 26.3 mpg
- Justin
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Re: Two into One Exhaust
One other benefit to going smaller is packaging and noise. I'm running a 3" and have had a hard time quieting it down. It's OK now, but took some work. You can also get tighter bends in a 2.5" than a 3", so wiggling it around the rear axle is easier.
- laffycaffi
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Re: Two into One Exhaust
Great tips - appreciate it.