View Full Version : Doing my exhaust. Need size of pipe.
blktbon20s
05-11-2006, 02:20 PM
I'm going to do it myself but i want know whats the diameter on the pipe?
Today i put it on my lift and the pipe right before the back resonator looks like its not a circle, looks like a oval:confused: ?
Also do u guys think its worth changing the whole exhaust, from headers - back, to a bigger diameter? like a 5"?
Spong
05-11-2006, 02:33 PM
I wouldn't recommend anything over 3" for an I6. I've read they need some backpressure.
Steve
blktbon20s
05-11-2006, 02:41 PM
So 3" is what comes to the back.Even tough its like squeezed?
Somebody in another thread, recently, measured the stock piping and found its 2.75" and not a full 3.00" as most of us thought. As posted above, you'll want a little back pressure in the system or you're economy may go south along with low end torque.
Spong
05-11-2006, 03:51 PM
2.75" is correct. I measured the stock pipe on mine and it was 2.75". So going to a 3" would give you slightly larger piping.
Prey521
05-11-2006, 03:56 PM
Would going up to 3"s have a negative effect on backpressure?
Spong
05-11-2006, 04:07 PM
It's such a small increase that I don't think it would. Going larger like maybe 4" might give a negative effect.
Prey521
05-11-2006, 04:11 PM
It's such a small increase that I don't think it would. Going larger like maybe 4" might give a negative effect.
In that case, going up to 3"s wouldn't help performance either?
Spong
05-11-2006, 04:19 PM
Changing exhaust isn't going to make a big performance difference no matter what you do, but you can hurt peformance. Going to a 3" could help a little.
Prey521
05-11-2006, 04:32 PM
Changing exhaust isn't going to make a big performance difference no matter what you do, but you can hurt peformance. Going to a 3" could help a little.
I'm gonna run the 3's with the flowmaster 50 SUV series that's being installed over the weekend.
Spong
05-11-2006, 04:38 PM
That's what I would do if I was running a single pipe.
Prey521
05-11-2006, 04:46 PM
That's what I would do if I was running a single pipe.
Ya, single pipe! Thought bout the duals, but decided against.
blktbon20s
05-11-2006, 08:46 PM
i might do 3" cuz i'm doin dual!:D
trailblazer02
05-11-2006, 08:49 PM
I also thought about doing duals, but I don't really want something to noticable. So I decided to go with the Bassani catback which has a single rear side exit pipe.
jjsryd
05-11-2006, 09:02 PM
When i get ready to do mine, i'll be going 3" from the cat.
ScarabEpic22
05-11-2006, 09:55 PM
i might do 3" cuz i'm doin dual!:D
If you do duals, you wouldnt want (and cant find a good muffler) 3" all the way back. You would want 3" from the cat to the muffler and then probably 2.25" or 2.5" max from the muffler to the tips.
And, 2.75" is the diameter of the stock exhaust, but it gets so crimped over the axle, I wouldnt be surprised if it was more like 2-2.25 there.
Spong
05-11-2006, 10:42 PM
i might do 3" cuz i'm doin dual!:D
If you do duals, you wouldnt want (and cant find a good muffler) 3" all the way back. You would want 3" from the cat to the muffler and then probably 2.25" or 2.5" max from the muffler to the tips.
And, 2.75" is the diameter of the stock exhaust, but it gets so crimped over the axle, I wouldnt be surprised if it was more like 2-2.25 there.
:iagree:
I wanted dual 3" but the shop said there wasn't enough room (this guy would do 3" if he felt it would be ok, I totally trust him). My duals are 2.25" Yeah, I would prefer larger but I doubt with my setup it would make any difference.
jkatan
05-13-2006, 01:31 PM
If you do duals, you wouldnt want (and cant find a good muffler) 3" all the way back. You would want 3" from the cat to the muffler and then probably 2.25" or 2.5" max from the muffler to the tips.
And, 2.75" is the diameter of the stock exhaust, but it gets so crimped over the axle, I wouldnt be surprised if it was more like 2-2.25 there.
Is that what pretty much everyone has? I went to my local exhaust shop and they said that I would have to go with 2.25" pipes from the muffler back. They want to charge me a lotta $$$$ for the Flowmaster I want (40 series delta flow with 3" inlet and 2.25" dual outlets).
Whats the consensus on Flowmaster? I hear a lot about Magnaflow and Borla, but my friend has a Flowmaster and I really like the sound. Any suggestions?
ScarabEpic22
05-13-2006, 02:42 PM
I have a Magnaflow with a 12" glasspack and love the sound. I think 3in in and 2.25out would be fine, Im pretty sure thats what Spong has.
jkatan
05-13-2006, 03:20 PM
Anyone have the Flowmaster 40 series delta flow on their TB? Id like to hear it before I get it done. Im especially interested if anyone has it on the 6cyl TB.
Spong
05-13-2006, 06:21 PM
IMO, Flowmasters sound the best. On various V8 powered vehicles I've owned, I've had Flowmaster, Super Turbo and Magnaflow. Magnaflow is too quiet for my taste.
I've got a FM 70 SUV on my TB. I had a FM 50 Delta to start and it sounded awesome but got to be too loud at interstate speeds. Be advised, the FM 40 series WILL BE VERY LOUD.
runzwitsisors
05-14-2006, 06:39 PM
I have used magnaflow on my past 3 vehicles and I love the sound!! even on 4 banger Lance evolution 8 it had a very deep tone... I have a magnaflow wide open 3" catback on my 4.2 trailblazer and it sounds very good. At idle it sounds stock but deeper. But once you hit the gas it sounds mean but not to loud. I would recoment magnaflow from personal xp. :D
ScarabEpic22
05-14-2006, 07:11 PM
I have used magnaflow on my past 3 vehicles and I love the sound!! even on 4 banger Lance evolution 8 it had a very deep tone... I have a magnaflow wide open 3" catback on my 4.2 trailblazer and it sounds very good. At idle it sounds stock but deeper. But once you hit the gas it sounds mean but not to loud. I would recoment magnaflow from personal xp. :D
Sounds like your setup is lot like mine man!:D 3" catback with Magnaflow (I have a glasspack too) out a nice tip!:yes: