go with the 2 1/2
Exhaust decison help
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Joined: Jan 2006
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From: Ventura California
Exhaust decison help
I am looking at purchasing an exhaust system for my 70/350. Choice is 2 or 2.5 inch pipes. Also choice of intermediate pipe weld to muffler or not. What do you all prefer? Any suggestions?
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2 1/2" system will work with stock manifolds, pipes start at 2" then increase to 2 1/2".
Recently installed 2 1/2" mandrel bent exhaust system on my 1970 L46 350/350HP 4 speed with 2 1/2" Rams horn manifolds. Also, went with Stainless Works 2 1/2" tips. I noticed that I have lost quite a bit of low end torque, but in the future I will be upgrading to a 383. I don't think I would of lost as much low end torque with stock 2" exhaust manifolds. Is yours a base 350/300HP, if planning on putting in a larger engine I would go 2 1/2" IMO, otherwise stay with 2" or maybe 2 1/4" with stock manifolds. Also is your car a 4 speed or auto, 4 speeds can afford some loss in low end torque vs auto. If you decide to go 2 1/2" I replaced my 2" exhaust hanger bracket for a 2 1/2" hanger that mounts under transmission.
Recently installed 2 1/2" mandrel bent exhaust system on my 1970 L46 350/350HP 4 speed with 2 1/2" Rams horn manifolds. Also, went with Stainless Works 2 1/2" tips. I noticed that I have lost quite a bit of low end torque, but in the future I will be upgrading to a 383. I don't think I would of lost as much low end torque with stock 2" exhaust manifolds. Is yours a base 350/300HP, if planning on putting in a larger engine I would go 2 1/2" IMO, otherwise stay with 2" or maybe 2 1/4" with stock manifolds. Also is your car a 4 speed or auto, 4 speeds can afford some loss in low end torque vs auto. If you decide to go 2 1/2" I replaced my 2" exhaust hanger bracket for a 2 1/2" hanger that mounts under transmission.
Last edited by CoolKars; Jul 8, 2006 at 05:11 PM.
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From: Ventura California
Mine is a base 350/300 with 4 speed. I do not plan on any other engine change. Sounds like there might not be any benefit to go 2.5 inch. Would the sound/tone be different? Now I am leaning towards staying with the stock 2 inch? I'm SOOOOO CONFUSED!!!!!
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Melting Slicks
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From: Piedmont Va
St. Jude Donor '11-'12-'13,'19-'20
I just changed from stock 2" to 2 1/2 and retained the 2" ramhorns. I installed Dr Gas X-Pip and Flowmaster Delta 50's. the low rpm tone got way lower...but at speed it is throaty and sounds awesome. I am still playing with the carb jetting, which was lean before, and way lean now, so I cannot comment on the power/torque just yet..but I will be way disappointed if it does not improve significantly
Thats intersting...Did you measure this somehow?...EVERYBODY say's changing to free-flowing exhaust provide a power gain..why would this decrease low end torque? I'm confused..
Another note, i purchased a pre-bent pipe kit from Ecklers. The shop told me it would have been cleaner to just have them fabricate it from scratch..but they did a heck of a job..
pic's on my homepage if interested..
I noticed that I have lost quite a bit of low end torque,
Another note, i purchased a pre-bent pipe kit from Ecklers. The shop told me it would have been cleaner to just have them fabricate it from scratch..but they did a heck of a job..
pic's on my homepage if interested..
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[QUOTE=dosoctaves]
Thats intersting...Did you measure this somehow?...EVERYBODY say's changing to free-flowing exhaust provide a power gain..why would this decrease low end torque? I'm confused..
Did not dyno, just seat of the pants feel. Probably picked up at higher RPM more HP. I believe the loss of low end torque is the result of reduced back pressure, maybe some other forum members with more knowledge can comment.
Thats intersting...Did you measure this somehow?...EVERYBODY say's changing to free-flowing exhaust provide a power gain..why would this decrease low end torque? I'm confused..
Did not dyno, just seat of the pants feel. Probably picked up at higher RPM more HP. I believe the loss of low end torque is the result of reduced back pressure, maybe some other forum members with more knowledge can comment.
Drifting
Joined: Jan 2006
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My 74 has stock 2" pipes that run to the rear of the car then 2.25 pipes an mufflers out the back. Need 2.25 or larger tail pipe to accomodate inlet/outlet available for super 40 flowmasters. Nice muffler with a deep rumble. They are louder than stock mufflers but not as aggressive as regular 40 flowmasters. Come in flat black and are smaller than stock mufflers so they fit very nicely up under the rear fenders. I want to hear the radio when I roll so I went with super 40 flowmasters. I do not have an X or H pipe and not sure I need it. Didn't want to pull off good pipes just to add H pipe. Besides, Chevy didn't put one on originally. Some say it helps balance the tone of the mufflers. Time to have that feature added is when you do a complete front to back pipes/muffler job so the H pipe can be welded into the new pipes when they are off the car. Find a muffler shop with an installer who knows what he is doing and will take time to get pipes,clamps, holders/mufflers etc. on straight. Good Luck!