exhaust on 440

[rattlesnake]

Need input on exhaust system for a 70 cuda 440 car.  I should run about 10:1 comp, competition cams super thumper specs. RPM range 2500-6400, duration 295 intake and 312 exhaust, lift 507 intake and 494 exhaust. I have 906 heads that have port matched and cleaned up a bit as far as the rough corners and such. The manifold is a Wiend team G. 391 gears w/ AT.

Questions are: does anyone have suggestions on header size and make for maximum HP. Has anyone ever used the shorty headers, I ask this because in the past I have had ground clearance issues with my hookers and how are they compared to traditional headers for fit and performance.
Any suggestions for carb size?

[Bart]

You should look at doug's headers they do not hang low, I put the 2.5 magna flow on my 383 makeing 452 hp.

[MEK-Dangerfield]

How do you plan to use the car? Street or strip?

I'm fine with 1 3/4" headers, but you might want to go bigger if you plan on racing it.

Doug's and TTI's are fine for clearance issues below, so no worries there. Shorty headers will compromise what you wish to achieve.

As far as carb size, I say at least 850 CFM.   

[rattlesnake]

It is primarely going to be a street car. I also had trouble with the hooker competition model rubbing my steering shaft. Any trouble there with the dougs or TTI headers and how well does thier ceramic coating hold up.

[cudabob496]

if around 500hp, then 1 and 7/8 header, and 2.5 inch mandrel bent exhaust with X-pipe
if around 600hp, then 2 inch header and 3 inch mandrel exhaust with X-pipe

I use dynomax super turbo mufflers. flow as much as flowmaster, but less noise.

X-pipe will give you 15 hp

[The Cuda Guy]

If Im not mistaken that is a very large intake for a warmed over 440, the Team G has like a 8000 RPM celing.  May want to look at a Holly SD or Eddy Perf RPM which has a range of like 2500-6500 unported.  But if you chose that intake for other reasons nevermind my comment.  As far as the exhaust headers go with big tubes around 1-7/8 to 2" which ever is more affordable.  TTi and Dougs have been the consistant recommended headers of this site for years, id start there.  440s make plenty of tq down low so losing a few lbs of tq low with the bigger tubes for a few hp on the top end is a decent trade IMO  .  Good luck.

Don

[nqkjw]

Got TTIs 1 7/8" on my 440 70 challenger.
The fit is superb but you have to make sure the crank centerline is where the instructions say.
Been on for abt 3yrs now but very few miles.The ceramic coating is still fine.
TTI also tells you very roughly 450hp is the changeover point from twin 2" to twin 3"
Mine is around 430hp and I went twin 3" so probably overkill

[HP_Cuda]

Don't forget if anything might be in your way. If you use Firm Feel quick ratio pitman and idler arms you have limited choices in headers unless you then go the modified route. But the ability to shave off turns off the steering is like music to my ears!

[cudabob496]

Got TTIs 1 7/8" on my 440 70 challenger.
The fit is superb but you have to make sure the crank centerline is where the instructions say.
Been on for abt 3yrs now but very few miles.The ceramic coating is still fine.
TTI also tells you very roughly 450hp is the changeover point from twin 2" to twin 3"
Mine is around 430hp and I went twin 3" so probably overkill

Beautiful Challenger! How did you get it to sit low in front and back?

[nqkjw]

Beautiful Challenger! How did you get it to sit low in front and back?

Thanks for that cudabob.
It IS a beautiful car and damned near perfect.
Spent 5yrs of my spare time doing it and it was a nice car before I pulled it apart.
I've laid claim that it's the 2nd best challenger in Australia and no one is disputing it.

As for suspension height - accident I think.
It was originally a 318 car and I've replaced the torsion bars for 0.92" units.
I always set my chrysler front end height at abt 3/8" clearance to the lower control arm stop rubbers.
The rear springs I suspect are a bit saggy but it still rides OK.

Here's a current pic of it for you.The Dart in the background is my latest effort.

[cudabob496]

Wow, some awesome Mopars down under!!

I was thinking you mighta used some drop spindals up front.