nate9207

i've got the 3.0 and i've considered puttin duals and headers. of course the downey ceramic headers would probably be the best choice for headers, but i'm not sure about the rest of the exhaust. i'd like to run true duals but i'm not sure if i should use 2" or 2.25" or 2.5" tubing and i'm also not sure what some good mufflers would be. i'm thinkin thrush or cherrybomb glasspacks.

lemme know what yall's 3.0's got. if any of yall have redone your whole exhaust system, let the braggin begin!

abecedarian

Don't have a 3.0, but I have an opinion:
... you are removing 3 cylinders from the O2 sensor readings, making it harder for the ECU to control your fuel mixture properly.
... you are negating most of the scavenging effect the stock (or well designed aftermarket) exhaust has.
... you are making the truck 'illegal' to operate on the street.

Now, having said that, I'd probably suggest 1.875" (1 7/8) or maybe even 1.75" (1 3/4) pipe on each side. You don't have enough exhaust flow to require 2" pipe.

You may be able to get around the scavenging issues I mentioned above by using an "H" pipe. You might even get around the O2 sensor issue I mentioned by using an "X" pipe and mounting the O2 sensor in the crossover.

nate9207

well i could care less about the o2's. mine have been bad for about 2 years and its still runnin strong. gets around 25 mpg hwy too. WITH 32's and stock gearing

4Crawler

iTrader: (3)

One thing to consider with true duals is the gas tank along the passenger side of the frame.

abecedarian

like I said, I only had an opinion. likewise, I don't see the need for 2" piping either.
If it's running fine even though somethings wrong (bad O2 sensor(s)) I'm in no place to argue.

nate9207

abecedarian: yeah i see what ur sayin abe. thanks for the input tho, seriously. its pretty funny watchin girls eyes open up a lil wider when they see that check engine light pop up. hell thats how i know everything's fine hahahaha jk.
i'm still not sure on the whole backpressure thing tho. i get mixed and biased opinions on it ALOT. lol

4crawler: yeah i've given that some thought tho. do you think that removal of the spare tire would suffice for muffler room?

abecedarian

I mentioned backpressure?
I only mentioned scavenging.

Well, maybe you could cross the pipe over and run parallel with the other exhaust, and stagger the mufflers so they don't interfere with each other? May not be a bad idea anyways... to have the muffler on the one side the same linear distance (based on the piping length from the head) as the other.
You might even be able to use a dual in / dual out muffler and elliminate a crossover....

nate9207

oh, my bad lol well whats scavenging then? haha

the muffler on it now is a huge-@$$ midas "coffee can on steroids" thats COVERED in rust. its quiet as heck and i dont really like it. also, my cousin gutted the cat when he had the truck before me lol. hell my whole exhaust is covered in rust. the powder gets in my eyes when i'm workin under it. or maybe thats dirt? lol either way it still hurts

abecedarian

scavenging is when the exhaust pulse from one cylinder passes over the 'pipe' from another, and due to 'venturi' effect (bernoulli to others) creates negative pressure on the pipe thus 'sucking' the gasses out.
Backpressure has it's place (arguable as it is), but we're talking about a differential pressure versus net pressure.

swaysidelife

i have a 3.0 with a 2in. cat back and a flowmaster 40. it sounds great

dropped_dime98

That with duals or single out?

swaysidelife

single out.

nate9207

sway how loud is that 40?

i thot about doin a 2inch pipe into a glasspack. i'll either eliminate the cat until the government makes me put one on or just get a high flow lol

here in bradley county, tennessee we ain't got no emissions testing

Tubbyfatty

I think high flow cats are around 100, but i may be wrong about that.

Whats the stock pipe diameter for a 94 with the 3.0?

Tubbyfatty

Speaking of exhausts. I was looking under my truck for kicks and giggles just now and....does this look like a cherry bomb glass pack?



total length is 30''.

This thing is way quiet tho...

jason191918

Most likely. Is there a pipe/hanger after it?

Tubbyfatty

Yea theres a pipe that goes over the axle then exits under the bumper.

nate9207

i read on another post that the stock pipe diameter is 2.125" aka 2 1/8" they say to keep the pipe sixe around that or 2.25" since 2.125" piping is hard to find.

that could be a cherry bomb, or a thrush, or a glasspack from jegs. thats the three red ones i'm familiar with. i'd like to get some purple hornies from jegs one day just for kicks lol.

its quiet eh? get that sucker really really hot and spray water on it to crack the glass. i've heard it makes em sound badass.

blackspyder

No 3.0 but IMO
duals with an X-pipe to connect the O2 sensor and single cat in. Cherry Bombs are nice but I perfer the Thrush Turbo muffler (cheap and sound good)
1 3/4" pre Cat, 2" post Cat (easier to find cheap mufflers for 2" than 1 3/4")

Jay351

Im running the stock manifolds, stock crossover. Right after the o2 sensor I had 2.25" single pipe welded in, that into a magnaflow hi-flow cat, that goes into a Flowtech glasspack straight out into a 3x16" boom tube.

Theres something like 2 small bends in the entire catback. When I chopped of the stock style tailpipe (I had the exhaust shop route it like the stock setup) and made my own straight back pipe it go rid of most of the "wet fartish" sound that the 3vze tends to get with a glasspack style muffler..
I think it sounds great, but its very loud. Like drive beside a car at full throttle and the alarms will go off loud..

Here is the exhaust when first installed: Note the old style tailpipe and spare tire...




Now:




I would recomend a set of LCE headers (get the street header kit!), I have seen it in person and the quality is awsume! Much better then that downey crap. Then follow that into a 2.25" SINGLE pipe, or 1.5" pipes if you want duels... Add a cat(s), unless you want a little extra top end power...