thinking of doing custom exhaust.
#1
11-28-2005, 10:23 PM
thinking of doing custom exhaust.
Well, not totally custom, just mix and match parts and make it a dual exhaust.
1. Air induction from MAC to begin with. (ok, so this is intake, sue me =p)
2. Set of MAC headers.
3. PowerCAT converters from Dynatech running out from each header.
4. Either 2 Flowmaster 40 series or the 50 series.
2.5" pipe all the way through.
what do you guys think?
1. Air induction from MAC to begin with. (ok, so this is intake, sue me =p)
2. Set of MAC headers.
3. PowerCAT converters from Dynatech running out from each header.
4. Either 2 Flowmaster 40 series or the 50 series.
2.5" pipe all the way through.
what do you guys think?
#2
11-30-2005, 02:35 PM
You will lose some low end torque. You can keep the headers if you want, and the intake is a good idea, but I would not go true dual unless your gonna wind it up more to offset the lost torque down low. I would go with a Flowmaster or a Dynomax or similar brand, and do a 3 or 3 1/2 inch single all the way out. It will keep a good sound, and you won't lose all your torque. The cats are a good idea, not because of flow, but the stock items seem prone to breaking up and rattling really bad.Just my .02
#3
12-01-2005, 05:59 AM
Food for thought: A 3 1/2 inch single pipe has approximately 9.6 square inches of volume. Duel 2 1/2 inch pipes would have a combined volume of 9.8 square inches. In my opinion, the 2% differential in volume is not significant. The single pipe is theoretically more efficient because it has less surface area to transfer heat and cause friction on the exhaust gasses. However, I seriously doubt anyone’s “seat-of-the-pants dyno” could tell the difference while driving the vehicle
#4
12-01-2005, 10:34 PM
Exhaust gas flow is a "science" that intrigues me. I have read quite a bit on the subject and draw on some stuff aI learned in my Thermodynamics class in college.
You can get less than what you want if you go too "free flowing" on the exhaust system. Exhaust gas velocity (which is obviously affected by pipe diameter) can impact perfromance.
I have heard many times you need "backpressure". I say that's bunk. It's more a matter of velocity.
Anyways, seems 2.5 inch pipe with true dual exhuast is a wee bit large for a 4.2. A 4.2 just doesn't pump that much air after all.
You can get less than what you want if you go too "free flowing" on the exhaust system. Exhaust gas velocity (which is obviously affected by pipe diameter) can impact perfromance.
I have heard many times you need "backpressure". I say that's bunk. It's more a matter of velocity.
Anyways, seems 2.5 inch pipe with true dual exhuast is a wee bit large for a 4.2. A 4.2 just doesn't pump that much air after all.
