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My 2 1/4 pipes too small?

DEL65

DEL65

Of The Morons
Hi my rebuilt 289 is back in the car and I estimate HP in the 300-325 rage, hopefully. The motor includes AFR 165's comp cam with .509 lift and 224/230 duration, Hooker Comp headers, generic Summit turbo mufflers.

I currently have 2 1/4" pipes and stock 1 3/4" 65-66 GT tips/trumpets. Will this system will choke my new motor? If so, what size should get; 2 1/2?. If I change to larger 2" stock-looking trumpets, will that still be too small?
 
IMO 2 1/4" pipes on a dual exhaust is more then enough.

No 4 banger has that big pipes. Just my opinion. :stu
 
2 1/2" pipes and a good set of headers. Air in, air out.
 
I would say the 2 1/4 is fine. The gas cools as it goes to the rear so you can go smaller after the muffler but that 1 3/4 pinch at the end may hurt performance.
 
"Opentracker" said:
I would say the 2 1/4 is fine. The gas cools as it goes to the rear so you can go smaller after the muffler but that 1 3/4 pinch at the end may hurt performance.
Click to expand...

He could add a ginormous fart can to fix that!
 
Hi, I'm glad to hear I can keep my 2 1/4 pipes and mufflers.

If the 1 3/4 tips are too small, will 2 inch tips work, or do I need to go larger? Thanks.
 
You didn't mention if your 2-1/4" system is mandrel bent... If not mandrel bent and if the over the axle bend is crushed to less than 2", then changing tips won't be much help.

For what it's worth, I have a similarly equipped 331 with 2-1/4" mandrel bent exhaust, short headers and it zips to 6200 with ease...
 
I'm going with 3 inch :hide Some may call it overkill, but it's the same price as 2 1/2 where I'll take it.

Bill
 
I can't recall if the pipes are mandrel bent, but I'll double check. Looks like I'll buy a pair of the 2" stock looking GT tips then. Thanks again for all the info, I appreciate it.

(Once I'm done, I have a pair of big tips and an enlarged shift hole for my T5...say that 3 times fast. )
 
"DEL65" said:
I can't recall if the pipes are mandrel bent, but I'll double check. Looks like I'll buy a pair of the 2" stock looking GT tips then. Thanks again for all the info, I appreciate it.

(Once I'm done, I have a pair of big tips and an enlarged shift hole for my T5...say that 3 times fast. )
Click to expand...

John-

We had stock GT tips modified to work with the fastback. We cut them off right where the chrome meets the pipe. Brought it close to 2". Just welded them to the exhaust pipe. I can get a pic I'd you are interested.
 
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