Has anyone noticed a difference in sound in 1 5/8" Vs 1 3/4" Headers?
1 5/8" Vs. 1 3/4"
- Thread starter BlkCCSvt
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At what power level?
Sitting at 525 atm, will be ramping it up tho.
Sound might be a little more hollower. Idk if i'd buy 1 3/4" over 1 5/8" headers because they sound better. Also depends on the rest of the exhaust. I'm sure if you went to a 1 3/4" primary header that you would also want a 3" midpipe and catback, which would add to the sound. But if you run 2.5" midpipe and catback I cannot see it changing the sound any noticeable amount.
1 5/8" Kooks LT's made more power that Kooks 1 3/4" LT's in the low and mid range and lost nothing to the 1 3/4" LT's at the top. Power level has little to do with which size makes more power. Engine size is the deciding factor. The two I discussed in my test was at 20lbs of boost. 20lbs of boost is 20lbs of boost no matter how you look at it. Boost is a measurement of the air that is stacking up in front of an engine. That is why larger displacement, cams, heads, better exhaust, etc lower the boost. If 1 5/8" headers lower the boost x amount and 1 3/4" don't lower it any further your wasting your time to continue going larger. Scroll to page 6 of the article below.
http://www.kennebell.net/KBWebsite/Tech_Articless_pg/links/tech_articles/MODS4MODS_COBRApart3.pdf
http://www.kennebell.net/KBWebsite/Tech_Articless_pg/links/tech_articles/MODS4MODS_COBRApart3.pdf
primary tube size should be based on A. the size of the motor, B. How much power it is producing naturally aspirated. C. How fast the motor is spun. I'd recommend 1 5/8" for 75% of cobra owners. DD street car 1 5/8", track car or car with more than 6-650rw 1 3/4"
That's my 2 cents.
That's my 2 cents.
1 3/4" primary and 3" exhaust is a recipe for "drone" (lower exhaust resonance/slower velocity). The smaller exhaust will scavenge the exhaust more efficiently. The bigger exhaust will work better at high RPM and big boost.
I would stick with 1 5/8" primaries and a 2 1/2" exhaust for most street applications.
what would u recommend for a car with a 3.4 25#s of boost and a powere lvl of 750 rwhp+ ? i was told 1 7/8
Without dyno time and track testing hard to tell. Exhaust systems have a mind of their own and no 2 cars will get the same results.
If that is going on a street car @ 25 lbs/750+ hp I would use 1 3/4 primary but would stick with 2 1/2" exhaust. If it's see more time on a drag strip (I say that because no road racer in his right mind would run that set-up) I would bump it up to 3" since 95% of the time the engine is near or at red line.
A 3.4 blower running 25 lbs
What is this car going to be used for? That blower is going to be put'N a hurting on your crankshaft snout (figure about 150 hp to drive the thing at 25#). If used primarily on the street a 2.3 Whipple at 15-20 lbs will be in its "sweet spot" with regard to efficiency.
Some great advice here. I personally just went from mac 1 5/8 with a catted x, to arh 1 3/4 3" collector and catted x. The sound was alittle different but not much, alittle deeper and slightly louder. Mainly made the switch due to boost being at 20 psi with the macs when the car is pullied for 17, switching to the 1 3/4 boost is back down to 17, plus have some other plans for more power so I was prepairing for that.
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