Now that the engine in my blazer is running good I'm planning on the exhaust. Long tubes are a for sure but it's the rest I'm contemplating. The only pre made kits are 2.25 piping. While I've got the skills to build a full exhaust, I don't have the time. So my question is would dual 2.25 be enough for a 383 or do I need to suck it up and have a dual 2.5 built?
CK5
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Dual 2.25 or dual 2.5 exhaust
- Thread starter centexk5
- Start date
smaller pipe = louder snappyer crackles under hard pull or high rpm .
i have had dual systems but anymore i prefer the cleaner smoother sound of a 2.5" to a y-merger pipe uni then out a single 3" pipe .
i have had dual systems but anymore i prefer the cleaner smoother sound of a 2.5" to a y-merger pipe uni then out a single 3" pipe .
I'll have an h or x pipe installed to help smooth the tone out. Two separate pipes sounds like crap. I'm planning on being around 400hp at the engine.
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I ran 1-3/4 primary tubes and 2-1/2 pipes on my 465hp BBC, and love the results...Im thinking 2-1/4 pipes would be similar on your SBC and convenient for you...Unless you plan on hitting 6K on a regular basis, then the slightly bigger system might be better for upper rpm performance.
GM never ran larger than 2-1/2 on any SBC vehicle up to 375 BHP. I dont believe anything bigger than 2-1/2 on BBC cars either.
GM never ran larger than 2-1/2 on any SBC vehicle up to 375 BHP. I dont believe anything bigger than 2-1/2 on BBC cars either.
The only problem with dual exhaust on one of these 4-wheel GM trucks is running the exhaust pipe down the right side. The hot exhaust pipe is so close to the transfer case that it boils the fluid inside the transfer case. This is the reason why GM designed a single exhaust pipe system that runs down the left side on GM trucks.
Fuel line and guage/pump wiring in that right side frame rail also
I run Edelbrock tes headers with 2.5" y pipe, 3" to cat,3" to muffler and a single 3" out the stock route.
I have to be SMOG legal for Calif.
I have to be SMOG legal for Calif.
It's interesting to note that if you take most modern vehicles, they are making close to the "Max HP for a dual system" with a single of that size, diesels being the exception.
Well after an Amazon gift card and credit card points, I bought a 2.25 dual exhaust with mufflers for $75. Figured what the hell why not. It'll be a bit before the 383 and knowing me I'll change the exhaust three times. Now to save for the headers.
And of course summit had 10% off so I just had to buy long tubes.
