Opinions on 3" exhaust system

[Michael Plummer]

Looking for more power out of my 94 GT and was wondering about a 3" exhaust sysem from MAC.

Currently the car has:
1 3/4" MAC shorties
2 1/2" MAC H-pipe
2 1/2" tailpipes with Magnaflow mufflers

Switching to:
Keeping the 1 3/4" MAC shorties because I don't like the issues I had with long tubes awhile back.
3" ProChamber with collectors that will matchup with the 2 1/2" collector on the shorties.
3" catback with MAC Flowpath Mufflers.

MAC engineers did a good job of getting me to believe that their mufflers are better and outflow most of the straight thru design in the market today. Am I crazy stupid for buying their sales pitch?

They gave me a good deal: $600 for (3" ProChamber and 3" cat-back w/mufflers) and free shipping.

Any comments good or bad?

Thanks
Michael Plummer

[SmokinStang]

My guess is that you won't see any gain, but maybe a 5-10 HP loss instead perhaps. You have a high HP car.....so you may just see a minor gain though. All indications tell me not worth it......which makes you crazy

You would obviously hear a difference factually. I would imagine that you may also run into some unwanted clearance issues also.

SmokinStang

[Chet-b]

i have to agree with Bob even though mac makes a great product i beleive that the money can be spent in other areas to improve your horse power and get more power per dollar spent. i dont think you will notice that much of diffrence.

Just my opinion...

[ToplessPony94]

From what I've seen over the years, anything bigger than 2.5" makes little if any difference on any car, and when a difference occurs it is often negative.

[Mustang5L5]

If you had a turbo or blower and making 500+ HP...then 3" would be okay.

Sometimes a free-flowing exhaust is a bad thing

[lxfiveo]

I dunno Mike....at your power level on the street, I'd be setting up my exhaust to what sound level and tone I want, not can I get 755 to the wheels or 747. You don't run it at the track, so it really is a non-issue. Your money is far better spent elsewhere.

[chasetopher]

I gotta agree with the $$ comments. I have mac LTs, Prochamber, and single chamber axle backs. Love the setup & sound but wouldn't spend thy $$ if it hadn't come with the car....

[Mustang5L5]

I dunno Mike....at your power level on the street, I'd be setting up my exhaust to what sound level and tone I want, not can I get 755 to the wheels or 747. You don't run it at the track, so it really is a non-issue. Your money is far better spent elsewhere.

That's a good point, but then you could also argue that you don't need the entire exhaust to be 3" to make the tone you want. Youncould have a 2.5" exhaust but install 3" tips and possibly get the same results.

[Michael Plummer]

Okay, Most people are saying spend money else where. My question to you folks is where? I liked the $600 budget (what I paid for the exhaust) but on my setup which I'm going to list. I can't find anything else to upgrade that will be money wise.

True, I'm not really a track guy and the car has no cage but I would like a bigger RWHP and RWTQ number. I like to have the bragging rights down at the local shops and part of me is a HP junkie.

At my HP I'm thinking the 2.5" exhaust has to be hurting me. At what point is a larger exhaust system warrantied?

Jimmy LaRocca always told me that when you have alot of pressure (back pressure) in your exhaust system and I do (14 psi) that the motor has to work very hard to make that HP. If I decrease the pumping loss on the motor, this should increase HP and TQ and the motor won't have to work so hard.

I APPRECIATE ANY COMMENTS

[Michael Plummer]

Block: DART 331ci internals good for 1200HP
Heads: TFS CNC 185
Camshaft: Custom from FREEZY74
Intake: Edelbrock RPMII
Fuel System: 80lbs, twin Pierberg pumps and #8 feed and #6 return
Exhaust: 1 3/4" MAC shorties
2 1/2" MAC H-pipe
2 1/2" tailpipes with Magnaflow mufflers
Throttle body: BBK 70mm
MAF: Pro-M 3" Pro-Tube
Supercharger: D1@20.6-21psi
Water/Methanol: Snow Performance stage 3
Tranny: Tremec TKO 600
Clutch: McLeod twin disc
31 spline axles
Gears: 3.55
Ignition: MSD 6A-2 programmable
Accel 300+ spark plug wires
Autolite 3924 spark plugs
Accel 300+ coil

Thats basically it for engine mods. Now where can I spend money to up the HP and TQ levels without breaking the bank.

Thanks