440 Magnum/Super Commando: Headers or Stock Manifolds?????

[A D I D A S]

Okay, finally after about a year of hemming and hawing, I have finally decided to rebuild the 440 in my '72 4-speed Plymouth 'Cuda.

The rebuild I have planned pretty much mirrors the one done in the April 2001 issue of Mopar Muscle. However, there is one substituion I want to make:

Retain stock manifolds instead of getting headers. My car sits kind of low, so I don't know if ground clearence is going to be an issue. Plus I am a little concearned about heat and leaking of headers, as well as plug access restriction. I haven't ever had a set of true long tube headers on a car, so I am not sure if my concearns are justified or not.

My only concearn is, is it worth getting a bigger cam (Comp Cams 274H), intake (Performer RPM), and possible headwork (bowl port/5-angle valve job at Tri-City Competition in Breckenridge, MI), without getting headers? I'm not looking to build a racecar, just a stout street combination.

Just wondering if anyone else has encountered this dillema, and if they have any experience with the manifold vs. header debate.

FYI: The April 2001 article on the engine dyno showed headers to be worth almost 30HP over a stock 1969 440 Magnum/Super Commando.

[jimbo7074]

Since you are considering larger cam, intake, and head work,I would definitely use headers.If you get a set that are ceramic coated,and have good thick flanges,most of your fears will be laid to rest.I know ground clearance can be a pain in the butt,just try to compromise if possible.With the stock manifolds I think you will really be holding back some horsepower.

[451Mopar]

I think a full TTI exhaust system would really help power and fit good, but I think the list cost is clost to $1,000!

If you decide to use the TTI stuff, call:
John Cambridge
Parts Manager
Ron Olson Dodge
800-397-8401

He got me my exhaust system for 12% below list cost.

If you decide to run the stock manifolds, they are only good for about 420 HP? In one of the Mopar magazines (I think High Performance Mopar) they went from extrude honed magnum manifolds to headers and gained over 60HP!

[Magnum440]

Yup, TTI, quality and good fitment are worth the price, IMHO. Opt for the ceramic coating, too. Headers do increase underhood temps, and the ceramic coating will help some.

[sbuc72]

Be careful with Headers and e-bodies. If you get the wrong type, you may have to take your steering apart to get them in/out.
If its not an issue installation isn't an issue (if the steering isn't in yet) then go with headers. otherwise, stocker manifolds will fit without any problems.

.sbuc72

[1350CFM]

How fast ya wanna go? Thats the first question. I run low 12's with manifolds on stock size street tires. I'm sure I will be in the high 11's this year. When running manifold the best thing to remember is BIGGER is not BETTER. Keep your cam a reasonable size and build your engine for low RPM torque. I only run 111mph in the 1/4 now with 3.91 gears. I plan on picking up at least 2 or 3 MPH when I switch back to 3.55's. If your interested we run a few races a year that are either "pure stock" or stock appearing" where everybody runs cast iron manifolds and intakes. Plenty of the guys arerunning 11's now and this is on stock Goodyear Polyglas or Redline tires! Check out the website in my sig. I would be happy to give you some tips on running good while still looking stock if your interested.

[PapaBato]

I'd also like to get some headers on my car, but i'm not sure which ones to get. I want to get ceramic coated, and heat wrap for my starter to make sure that it won't burn up on me. Would i have to modify my steering or shift linkage or anything if i got headers in my car ('68 440 in '67 satellite)?

[1350CFM]

My brother put a set of Thorley headers on his 440+6 RR ans said they are CRAP! The fit horrible and he only picked up 2/10's. Not worth the hassle to me. If I were going to buy a set I would buy TTI's then they would also line up with their exhaust system.