need some exhaust experts!

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Apr 26, 2002 | 01:07 PM

spoon059

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Mountain Pass

Joined: Apr 2002

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need some exhaust experts!

Okay, after reading up on a lot of stuff, this is what I think I'll do. I have a 95 with stock dual headers. I plan to leave them in, and scrap everything behind it. I want to keep the one cat, and hollow it out, and buy a high flow cat. I will also buy 2 18" cherrybombs, 2 nice tips, and whatever tubes I need. I plan to install a custom true dual exhaust that will exit at an angle in front of my rear wheels, Lightening style. This would mean one of the headers has the high flow cat and cherrybomb, and the other header has a hollow cat and cherrybomb. Would this sound awful, with some sound inhibited by the working cat and some not, and therefore should I install an X-pipe after the cats? Or do my exhaust professionals out there think this might work? I think I can get this done for $200 to $250 (depending on whether or not I need to buy 2 high flow cats at $60 a piece!), and my objective is to have a nice sounding exhaust from the 300, not loud and annopying, but not quiet the way it is now. Please give me some feedback if you have thoughts or ideas about this!!!

Apr 26, 2002 | 05:36 PM

thatdude

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From: McPherson, Ks

need some exhaust experts!

I'm not an expert but I would pop for a new SET of cats for backpressure (performance) reasons.

Apr 26, 2002 | 06:30 PM

GammaDriver

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From: Southeast FLA

need some exhaust experts!

[updated:LAST EDITED ON 26-Apr-02 AT 07:33 PM (EST)]Catco, i believe, makes a dual-pipe into single high-flow catalytic that can replace your whole envisioned mess of catalytics/hollowed out junk. It is designed specifically for our trucks, and would bolt right up to the manifolds, plus it has a oxygen sensor hole. It would be MUCH easier to install it than to try to retrofit a Universal high flow cat.

I totally disagree with keepign two inline cats though. Backpressure is a complicated subject, and I'm not going to get into it much past the fact that your two stock exhaust manifolds would create be plenty of backpressure alone, so the subtraction of two cats for a single high flow cat will not hurt your low-end nor your engine.

Apr 26, 2002 | 10:03 PM

spoon059

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Mountain Pass

Joined: Apr 2002

Posts: 102

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need some exhaust experts!

What if I left the first cat in, because I looked at it and the O2 sensor (I assume) has piping up into the main engine block, and looks difficult to bend or rearrange, and take out the second cat. Wouldn't that reduce some of the restriction but still leave sufficent backpressure?

Apr 26, 2002 | 10:45 PM

GammaDriver

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From: Southeast FLA

need some exhaust experts!

Sufficient? Plenty.

Mine's that way.

Apr 26, 2002 | 11:00 PM

spoon059

Thread Starter

Mountain Pass

Joined: Apr 2002

Posts: 102

Likes: 20

need some exhaust experts!

Excellent! Thanks for your knowledge, it will hopefully make my project run a lot smoother. just out of curiousity, what do you run behind that, and how does it sound? I want a nice truck rumble that isn't annoying as hell, but doesn't sound like I have a mouse grunting under the hood.

Apr 26, 2002 | 11:20 PM

GammaDriver

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From: Southeast FLA

need some exhaust experts!

[updated:LAST EDITED ON 27-Apr-02 AT 00:30 AM (EST)]I'm just running some aftermarket OEM-design muffler (perhaps a Meineke or a Walker?) that came with the truck. It's just a little more lively than it was - but it still sounds quiet, yet low in tone (what tone there is) in the low revs - which is pretty much what I like. I like the individual, slower thump sound over a sporty sound.

It seems to me the more a muffler flows the higher the tone gets. I'm thinking that a good tone might come out of my stock-ish muffler, yet bigger pipes on both sides of it.

(one of my examples of exhaust tone was that my step-dad had an El Camino with a 350 c.i. that had true, no-catalytic duals with very standard mufflers - it had a real nice, real low thump, thump sound/growl that turbo/high-flow/glasspack mufflers just don't seem to give).

There's some really experienced info on the two (it says three, but there wasn't anything on the third in my broswer) pages of this post:

https://www.ford-trucks.com/dcforum/DCForumID39/1240.html

Edit: I'm still looking for the best backpressure argument posts, but this was one that I remembered and just found:
https://www.ford-trucks.com/dcforum/80_96/2554.html