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Discussion Starter · #1 ·
Thank You for stopping by. I have an Exhaust question for you performance specialist.

For some stupid reason Ford Decided to run H-Pipes On the exhaust of their V8's Vehicles. ( Not sure if this applies to all v8 vehicles) From my understanding, The X-Pipe is all around better for any V8's ( Or v6 for that matter ) with true dual exhaust. I was plotting up exhaust ideas in my head.

The solution I have come up with for my car is: Hack off the part after the secondary cats, Replace with 2.5' Magnaflow X-Pipe kit with Cut-outs, And leave the rest of the exhaust stock. In theory, I would have the Best Of Both Worlds. I could cruise around in Peace and Quietness, Flip the switch to the electric cut-out opener and "Raise Hell".

What are some of the ideas you Ladies & gentleman have, Or have applied to vehicles you have, or have had. Thanks

Jason~:tup:
 

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Discussion Starter · #2 · (Edited)
Hmm. I know some of you truck guys have modified your exhaust. I'm going to assume trucks already have x-pipes? :shrug:

I guess my question is. Would it be better to do a full exhaust cat-back, Or go the cut out route? Wouldn't the cut outs be a bigger gain than better flowing mufflers anyways?
 

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DONT put cutouts on a 4.6, Ive heard them on a Crown Vic and they sounded horrible! I didnt put true duals on my truck, instead I got ride of 1 of the 2 stock cats, did 3" single inlet to 2.5" dual outlet with 4" tips coming from a Flowmaster 40 Series on my truck. It sounds awesome, but is very loud, especially when im towing! Im sure gutting my truck taking out the insulation and rugs in favor of Rhino Liner doesnt help though!

Most stock truck have single exhaust from the factory, unless your buying a Lightning, SuperBee Ram, etc. On some trucks, an X or even an H isnt really possible without getting expensive. Pipes should be realtively close together to run an H, which isnt always doable because of a transfer case, driveshafts, torsion bars, crossmembers etc. in your way. Most custom duals on a truck are true duals from the manifolds back, some sound good, some sound like shit.

But because of how much room you have to work with on your Interceptor, I'd get a set of headers, a nice x-pipe kit and 2.25-2.5" piping and your choice of muffler depending on how loud you'd like it. Go 2.5" if there are no mandrel bent kits out there available and crush-bent is your only choice (if youre getting it custom bent locally).

-Tyler
 

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Discussion Starter · #4 ·
Thank you tyler. My only problem is. I want to retain my stock sound for normal cruising. Flowmaster, magnaflow ect mufflers are kinda loud for everyday use for me. Cut outs would only be for drag strip or showing off. I would still retain all 4 cats, I don't think it would sound that bad when open. If i was removing the cats and running straight from the headers/manifolds. Then i agree it would sound terrible.
 

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if you're putting the cutouts at the corssover pipe - you lose all benefit of scavenging.

also - exhaust on a v8 anything is highly dependant on what you have done BEFORE said crossover.

longtube or shorttube headers? if the answer is neither, ie: stock... just run the stock stuff, high flow cats, and get a better flowing set of magnaflow turbo mufflers.. not straight through, so not very loud.. but still better flowing than the horse whisperer stockers.

If the answer is long tubes - keep the h crossover, and enjoy your lowend torque. run 2" piping off each head, and post crossover to the cutouts, and have fun.

If the answer is short tubes - go with an x crossover, but don't put the cutouts there. cutouts always go post crossover, unless you're just doing it for the noise... god knows you won't show any track gains (unless you're running heavily ported non stock heads with an aggressive cam, and rocker)
 

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Discussion Starter · #6 · (Edited)
Thank You Steve. I Have stock manifolds at this moment. The cut outs are after the crossover point just before the mufflers. I do plan on getting shorty's (headers) in the future. So the Crossover would be a good mod to get either way. Just thought the cutouts could substitute getting mufflers and having to deal with the wicked over the axle pipes :tdown:

I'm still looking into the high flo cats. Might remove the 2 secondary cats and leave the 2 primaries stock. You guys are giving me a better outlook on this. Always good to here views from others :tup: Karma
 

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the cats and mufflers are your bottlenecks on that engine... so yeah, higher flowing cats, and decent (not even great) mufflers will make a huge difference for now. skip the cutouts until you're making enough power to need them.
 

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Discussion Starter · #8 ·
Agreed. Removing secondary cats.

Plan: Stock primaries, x-Pipe, Turbo Mufflers Flowing through 2.5' Crush bent pipes. :tup:
 

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you could allways get dynamax mufflers . i had those on my stang ,an it didn`t sound really loud either
 

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By and large, the difference between H- and X-pipes centers on sound and torque. H pipes tend to give V8s an old-school, muscle-car rumble whereas X-pipes lend a higher-pitched, almost "Euro" sound. A properly done X will give slightly more power than an H but I believe the H will give a bit more torque down low. The performance difference is really minor and I think the choice of which to go with is made mostly because of one's sound preference. I suspect Ford put H-pipes on Mustangs (etc) because of the sound. Packaging and cost may also have played a role...who knows?
 

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Discussion Starter · #11 ·
^Have you modified the exhaust on your 02 GT ? I see you've got it pretty modified. What mufflers are you running and what size exhaust?
 

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^Have you modified the exhaust on your 02 GT ? I see you've got it pretty modified. What mufflers are you running and what size exhaust?
I had installed an MRT catted H pipe on the car but was forced, last summer, to put the factory H back on to pass an emissions sniffer test. It's still on there now. I may put the MRT back on to see if the supercharger likes it...

My catback is a Steeda.
 

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Discussion Starter · #13 ·
No Headers?

So the stock H Pipe is ok? Maybe just have a larger h-pipe made 2.25'-2.5'. You wouldn't be any chance have any exhaust videos would ya? I'm curious as to how loud this setup sounds. We basically have the same motor from my understanding.
 

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open headers yay wtf omg idk idc weeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
 

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No Headers?
Factory logs. Shorties don't gain anything and LTs have several issues for me: packaging is very tight (generally, the K-member has to come down to install them) and loss of the ability to use the factory midpipe (important to me for sniffer testing.)

So the stock H Pipe is ok? Maybe just have a larger h-pipe made 2.25'-2.5'. You wouldn't be any chance have any exhaust videos would ya? I'm curious as to how loud this setup sounds.
Check this one:

http://ca.geocities.com/[email protected]/My_Homepage_Files/Download/Steeda_Idle_Rev_Driveaway.MP3

This is the MRT and the Steeda catback made a few years ago, before the blower installation. I think this is before my Comp Cams too...

We basically have the same motor from my understanding.
Yep, pretty much. I think the intake manifold is different but otherwise, it's essentially the same 4.6L 2V mill.
 

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Discussion Starter · #16 ·
Exhaust:
sounds great. I might keep the stock logs. Shorty's are a pain for this year Crown Vic.
Gears:
I have. 3.27rar I'm seriously considering going 3.73 rar.
Cams:
If i'm not mistaken, Interceptors have the 262ah cams, Or something aggressively similar.

Still a lil bit louder than i want, But i may have to bite the bullet. When you were N/A did you use the Steeda U/D Pullies?
 

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Gears:
I have. 3.27rar I'm seriously considering going 3.73 rar.
I've got 3.73s and love them. They'd be a good gear for the heavier Panther platform. Doesn't give any more wheel HP but the car feels livelier with them around town. The Mustang GT came with a 3.27:1 rear stock and I believe the CV did too. On the highway, you'll see engine RPM increase by about 14% with these gears. If you turn 1800RPM at 70MPH now, you'll see about 2050 with the 3.73s. It's not a huge penalty.

Cams:
If i'm not mistaken, Interceptors have the 262ah cams, Or something aggressively similar.
At most they'll have the Ford "PI" cams which aren't nearly as aggressive as the Comp 262s. With the 262s I get a nice lope to the idle compared to the glass-smooth idle with the factory PI cams. At 0.050" lift, the Comp cams have 226/230 degrees of duration on the intake/exhaust lobes and a lift of 0.545" on both sides. The PI cams have intake and exhaust durations of 186/194 and lifts of 0.505/0.534 lift respectively.

Still a lil bit louder than i want, But i may have to bite the bullet. When you were N/A did you use the Steeda U/D Pullies?
No, I had a set of March piggybacks. Good pulleys and never gave me any trouble plus they retained the factory damper and inertia ring which is critical to prevent oil pump issues.
 

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Discussion Starter · #18 · (Edited)
Cams:
I was thinking about going hi-tech stage 2. But i'll run the stock "PI"s I plan on getting rid of the 4.6L anyways.
U/D Pullies:
I've heard bad things about piggy backs, SFI one piece units are the way to go, Based on my research. Piggy backs still give about the same gains though :shrug:
Gears:
Yea, i think i'll go 3.73, that should drop at least .5 sec of 1/4 or something close to that.
 

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Cams:
I was thinking about going hi-tech stage 2. But i'll run the stock "PI"s I plan on getting rid of the 4.6L anyways.
Getting rid of the car or the engine? If the engine, with what will you replace it?

U/D Pullies:
I've heard bad things about piggy backs, SFI one piece units are the way to go, Based on my research. Piggy backs still give about the same gains though
I never had any problems with mine. The most important thing to consider with UDPs, especially for the mod motor, is the damper tuning. The mod uses a gerotor oil pump driven right off the snout of the crankshaft and it uses brittle powdered-metal gears. If the crank snout damping is insufficient, the torsional vibrations can actually cause the oil pump gears to shatter. If your goal is to reduce the drive ratio to the accessories, piggybacks will give that while also retaining the damping Ford designed in.

If you have your heart set on a one-piece, I've heard good things about Steeda.

SFI doesn't necessarily mean that the damper will function to protect the oil pump gears (for instance)...it more means that the part was built such that it won't come apart and cause a hazardous condition to arise.

Yea, i think i'll go 3.73, that should drop at least .5 sec of 1/4 or something close to that.
I don't know about 1/2-second but it'll help get that thing moving :)
 

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Discussion Starter · #20 ·
I'm getting rid of the engine. This will be a year or 2 down the road. I'm replacing with SC 5.4L from lightning. But for the time being, i want do build up the car. Exhaust,trans, suspension. I will install 3.73 gear with carbon clutches and t-lok.
 
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