Installing 3 inch true dual exhaust
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http://www.summitracing.com/parts/hed-58070/overview/year/1980/make/oldsmobile/model/cutlass
If these are the headers you have I would say these are far too big for a stock 307 since they have 1-3/4" primary tubes which practically puts this in "race header" territory, if you plan on installing a bigger engine in the future then these will probably work fine but if not you will loose a lot of low end torque even if you reduced the exhaust down to 2-1/2"
If these are the headers you have I would say these are far too big for a stock 307 since they have 1-3/4" primary tubes which practically puts this in "race header" territory, if you plan on installing a bigger engine in the future then these will probably work fine but if not you will loose a lot of low end torque even if you reduced the exhaust down to 2-1/2"
So with that being said. Would you happen to know what the best option would be for exhaust and headers performance wise. Without putting in a bigger engine.
For my 86' Regal which also has a stock 307 I looked at those headers but decided against them because of the size of the primary tubes.
I decided to just install all new Walker 442 dual exhaust that bolts right to the catalytic convertor and the pipes are 2-1/4" diameter and even though I gutted the catalytic convertor it is still relatively quiet which is what I wanted, I don't really want it to be loud because then people will expect to be fast and it won't be.
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A 3 inch system will likely do nothing for power, and may even reduce power, with the turbulence it may stir up. The folks who know would never recommend 3 inch. A
2 1/2 inch will work with a mildly built big block..
Of course if you wanna run a 632 inch big block Chevy, the 3 inch would work fine !!
2 1/2 inch will work with a mildly built big block..
Of course if you wanna run a 632 inch big block Chevy, the 3 inch would work fine !!
I don't see any issues with the 3" collectors. Sure they're overkill for a 307 but it won't hurt anything. You obviously aren't going for power lol!
Damn near every header collector I have seen is 3" or bigger. All you need is a reducer to reduce it from 3" at the collector to 2.5" for the exhaust. The reducers are cheap and more than likely can be found in any auto parts store.
I got my old 2.5" dual exhaust kit complete from Summit a few years ago. Fit awesome and was a breeze to install.
Damn near every header collector I have seen is 3" or bigger. All you need is a reducer to reduce it from 3" at the collector to 2.5" for the exhaust. The reducers are cheap and more than likely can be found in any auto parts store.
I got my old 2.5" dual exhaust kit complete from Summit a few years ago. Fit awesome and was a breeze to install.
I've got blackjack headers for now, and yeah it has 3" collectors, most kits that I know come with the collector reducers to the pipe size of the kit. There is no reason to run 3" unless you are going big block with lots of power and need that thing to breath. I'm running 2.25" now but am upgrading to a 2.5" and that's the biggest I would need. 2.25" is a bit restrictive on my current motor build and 2.5" is supposed to assist with some issues.
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