69 390/427 exhaust
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From: Flanders NJ
69 390/427 exhaust
I am faced with replacing the exhaust system on my 69 390/427 and I am wondering about going to a 2 1/2" system from the current 2". It LOOKS like the factory manifolds are already 2 1/2 and the reduction is taken in the connectors. I haven't seen any 2 1/2 inch systems offered in the catalogs. Will the 68 pipes setup fit the chassis? Will it fit the 69 factory manifolds? Why in the name of good sense did Chevy decide on the smaller pipes for just one year?!? Sorry for the wordiness of this, but I appreciate any ideas or comments...joe
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When I bought my 68 427/390 last year it had a 2 inch system on it. I put a 2 1/2 inch system with DynoMax mufflers on. Big difference in performance and sound. It really woke the car up. That big block wants to breath. I had a local friend with a muffler shop custom bend a system for me. Good luck with yours.
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From: Huntersville NC
From a mass production/ assembly line standpoint, 2" would be cheaper than 2.5", and cheaper still would be to use the same size exhaust for all cars regardless of the engine used. Just to answer part of your original question.
Drifting
Joined: Nov 2002
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From: Loveland, CO
Joe, I ordered the 2 1/2" system from Mid America for my '69 big block. Only downside was at the back end where the exhaust tips attach. They were reduced to 2" to fit the stock tips. I had the muffler shop cut off the ends and weld on new larger tips. It seemed silly to have the larger pipes necked down at the very ends. I installed the chambered system and boy is it impressive sounding.
Ralph
Ralph
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From: Flanders NJ
thanks to you all. The 2 1/2 system is the way I am going to go. I was considering the chambered system also since I was thrilled with that system on my 1967 442 when I was just a kid. Thanks again...Joe
Drifting
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From: Loveland, CO
Joe, I couldn't find the one for my application in the catalog either. I called them and they steered me in the right direction. One of their models fits multiple years and thats what they sent me. And, it fit. So give them a call and ask what you need for your application.
Merry Christmas, Ralph.
Merry Christmas, Ralph.
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From: Flanders NJ
Ralph:
Many thanks and a very Merry Christmas! My wife is giving me " THE STARE" because I am online with my "Corvette Buddies" on Christmas morning. Gotta go... will converse soon...Joe
MERRY CHRISTMAS AND THE FONDEST HOLIDAY WISHES TO ALL
Many thanks and a very Merry Christmas! My wife is giving me " THE STARE" because I am online with my "Corvette Buddies" on Christmas morning. Gotta go... will converse soon...Joe
MERRY CHRISTMAS AND THE FONDEST HOLIDAY WISHES TO ALL
Drifting
Joined: Nov 2002
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From: Loveland, CO
Joe, at least you are not out in the garage yet.
When our friends come over for Christmans dinner, I plan to take them in the garage first to help me put the body back on a '66 frame (they are expecting it).
Merry Christmas. Ralph.
When our friends come over for Christmans dinner, I plan to take them in the garage first to help me put the body back on a '66 frame (they are expecting it).
Merry Christmas. Ralph.
Melting Slicks
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From: Nevada City California
1969 used 2" exhaust piping because the optional sidemount exhaust system was also 2". '68, '70, '71 & '72 big block optioned cars all used 2.5" exhaust piping, since no sidemount exhaust option available.
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From: Flanders NJ
Hi Ralph. I;ll have my father and daughter in the basement to review my porgress when they get here (more of "THE STARE") but its all family fun.
Early Shark: That sounds like the most likely explanation, ince the previous and following years had both. Also, some of the 69 small blocks had 2 1/2 exhaust as well? All the best holiday wishes to all...Joe
Early Shark: That sounds like the most likely explanation, ince the previous and following years had both. Also, some of the 69 small blocks had 2 1/2 exhaust as well? All the best holiday wishes to all...Joe