Finally done fixing.

[MWFan]

So I hope to do some performance stuff.
When I bought the car a couple of months ago it was pretty, but had some issues. Lousy idle due to intake vacuum leaks, heater would not shut off, overheating at idle, leaking trans at parking cable. Nothing serious, just aggravating.
Now that it is solid in the driveability dept, I want to do a couple of mild performance mods. The car has a 440 suposedly built to Magnum specs, 452 heads, 483/284 purple cam, Edelbrock 600, pushbutton 727 with shift kit, Dana 60 with 354 gear. It has a 2.25" exhaust with what sounds like stock mufflers and somebody welded a short section of 2" pipe at the end of the tailpipes to attach some pretty nice stainless tips.
My plan is to get rid of the 2" section of pipe, make it all 2.25", install some chambered performance mufflers, put in an H pipe and replace the Eddy 600 with a Holley 750 vacuum secondary. My concern is the stock stall converter. Hoping that the bigger carb won't effect the throttle response which is very good with the little 600.
Any input?
Thx.
Bernie

 

[khryslerkid]

With the 3:54 gear you're useing it should be ok. I'm useing the 3:23 with a stock converter and about the same cam (Sum 6401). Running two 600s, one to one linkage, not progressive.

Would I like a higher stall converter, sure but what I have works ok for street use. It's not a dog by any means.

 

[MWFan]

With the 3:54 gear you're useing it should be ok. I'm useing the 3:23 with a stock converter and about the same cam (Sum 6401). Running two 600s, one to one linkage, not progressive.

Would I like a higher stall converter, sure but what I have works ok for street use. It's not a dog by any means.

Thanks KK. I Appreciate the input, I read your build thread and your info on the fan shroud you built. I emulated the shroud in fiberglass. Love your work and respect your opinion.
Thx, Bernie

 

[slepr1]

Imo, your exhaust is a bit small. My 340 cuda had a 2.25" exhaust. You will need a 2.5" exhaust. I'd estimate your 440 to be around 375-400 Hp depending on your compression, which is in 2.5" range. I think your stock converter will be fine.

 

[MWFan]

Imo, your exhaust is a bit small. My 340 cuda had a 2.25" exhaust. You will need a 2.5" exhaust. I'd estimate your 440 to be around 375-400 Hp depending on your compression, which is in 2.5" range. I think your stock converter will be fine.

Thanks! Compression accd to the build sheet is just about 9.4/1. Replacing the system is not currently in the budget but I hope getting rid of the stock mufflers and 2" section on the very end of the exhaust and adding the H pipe will help some. I read that the H pipe will mostly benefit low end but I'm guessing that relieving the restriction of the muffs and 2" section may help a little on top. At least the system should sound more respectable and Im hoping I blip the needle on the seat of the pants dyno...
My main concern is will the car bog with a bigger carb...
Thx.

 

[Don Frelier]

The 2" section after the muffler is not a real source of backpressure, especially if it's straight.
H-pipe and mufflers will give you the most improvement for your money.
If you have nice stainless tips I would keep them for now.
A well tuned 750 should not bog.

 

[MWFan]

The 2" section after the muffler is not a real source of backpressure, especially if it's straight.
H-pipe and mufflers will give you the most improvement for your money.
If you have nice stainless tips I would keep them for now.
A well tuned 750 should not bog.

Thanks Don. The 2" section at the end is definitely not straight, they are turn downs to exit under the rear bumper, nearly 90º. The 2.25 replacements will be nearly straight.