Glenn Menard, Memphis, TN, 1973 Plymouth ‘Cuda 440
I am planning on replacing the exhaust system on my ‘Cuda and wanted to get your opinion on a few options. The car has a fairly”warmed over” 440:
0.040 over – Kieth Black pistons (set up as floaters) – true C.R of10.89:1 – Top of block chamfered to unshroud valves – Stage V heads, ported using Mopar’s porting templates, chambers cc’d and polished, 11/32″ stem valves (bronze guides), titanium retainers, Crane 1.6 rockers – Hughes solid cam 0.050″ duration ~ 238 intake, 244 exhaust; lift ~ 0.569 intake, 0.579exhaust (I don’t have the exact specs here at work, but it’s the earlier version of their max velocity series) with matching springs – Assembly is balanced – Mopar M-1 single plane intake – Holley 850 carb (list 9381 if I remember correctly – came with no choke). I used to ride submarines so I had a lot of time to plan this one!
It cruises at ~ 3400 RPM on the highway. The car does not see any track time, but I must admit I do get on it once in awhile. The shift light is set at 5800 and by the time this old fart reacts, I’m hitting 6100 – 6200 rpm’s when the 727 shifts. (It seems every Mustang owner thinks he has the fastest car in the world and of course it is our duty as Mopar owners to show the motherwise!)
I am currently running Hooker Supercomp headers with 1 3/4″ primaries and 21/2″ pipes (w/crossover) and flowmaster mufflers. I am planning on installing a TTI system, but am not sure of the best way to go. Options are:
1. Keep the Hookers and run either a 2 1/2″ or 3″ system (TTI’s web sites hows they offer adapters for the Hookers).
2. Change to TTI headers (1 7/8″ or 2″ primaries) and run either 2 1/2″ or3″ system.
I have heard for years that the 440 responds best to 1 7/8″ primaries, but have also heard good things about the 2″ headers. Is a 3″ exhaust system too big for the street (sacrificing flow velocity for upper rpm capability that the car never sees)? I know you guys have done some extensive testing with different exhaust configurations and would value your opinion.
The TTIs are awesome headers in any size. For your application, it’s kind of a toss-up whether to use the 1-7/8″ or 2″ primaries.
HP-wise, the Hookers really aren’t bad, either, the biggest advantage that the TTIs have is fit, freedom from rattles, etc.
For anything over 450-475 HP, the 3″ pipes are the way to go. Again, based on your specs, it’s borderline. When pressed, however, since there’s little doubt that you like to crush a little rice now and then, I’d say go for the max: 2″ primaries, 3-1/2″ collectors, and 3″ pipe all the way back.