496 stroker exhaust

[diesel_lv]

I am building a 383 stroked to 496. It should be in the 650hp range and even more torque. All hp in by 5,200 rpm. Following this build, https://www.hotrod.com/articles/chrysler-383-big-block-mopar-for-the-masses/ , but 496 instead of 450 and roller cam. I am going to use TTI 2" stepped to 2-1/8" headers. O2 sensor for the fuel injection. I am thinking of putting in 2 high flow 3" 200cpsi catalytic converters and 2 high flow 3" mufflers. Keep drone down and exhaust smell down. Only like the smell of 100+ octane and 2 stroke Castor 927 premix. Then 3" dual out the back. Any thoughts on this? Advice on what is good or bad? Thanks.

 

[PurpleBeeper]

My 2-cents?
a. catalytic converters are not necessary
b. the cam is still too big for a street motor
c. the Stealth heads aren't the best choice & the CNC porting is too expensive

Sorry to rain on the parade

 

[forphorty]

That Comp 231/237 cam would be a baby in a 496. I would do the Trick Flow 240 over the Stealths.

 

[diesel_lv]

My 2-cents?
a. catalytic converters are not necessary
b. the cam is still too big for a street motor
c. the Stealth heads aren't the best choice & the CNC porting is too expensive

Sorry to rain on the parade

I'm thinking catalytic converters to keep smell down and to help keep highway drone down. Is there a reason you don't think they are necessary other than emissions laws?
Actually the cam I'm using is the XR 280HR roller cam. Should be very good bottom end in a 496. But thank you.
Already have the heads and porting done. Heads and porting was 2k. I don't know if there is another head out there that's complete with valves, seals, springs and retainers for under a grand. Then a grand for porting.

 

[diesel_lv]

That Comp 231/237 cam would be a baby in a 496. I would do the Trick Flow 240 over the Stealths.

The Trick Flows are 1k each and still require at least a valve job. Possibly more porting to match up to the porting being done on the Stealth heads.

 

[diesel_lv]

Thank you both for your replies. As for the exhaust, anything else I can do or not do? This car will have GV overdrive, Already have it, FiTech fuel injection already have it. It will "NEVER" see the drag strip. This was my great grandmothers car and I just really enjoy torque. It will be driven quite a bit. I am 53 and so over the exhaust drone. That is why I am considering Cats. Thanks.

 

[PurpleBeeper]

I'm thinking catalytic converters to keep smell down and to help keep highway drone down. Is there a reason you don't think they are necessary other than emissions laws?
Actually the cam I'm using is the XR 280HR roller cam. Should be very good bottom end in a 496. But thank you.
Already have the heads and porting done. Heads and porting was 2k. I don't know if there is another head out there that's complete with valves, seals, springs and retainers for under a grand. Then a grand for porting.

OK, I think your cam is reasonable & you have all the parts and I'm sure it will run fine. Thinking out loud on the exhaust, you might just think about some "hemi resonators". I've got stock-type Walker mufflers & have been considering splicing in some cherry bombs into the tailpipe area as a "cheap hemi resonator knock-off" or maybe some actual repro ones if they're not insanely expensive.

For the cats....they do reduce sound more than you would think. An obviously, they reduce hydrocarbons...but I'm thinking your fuel injection setup with have the air/fuel mixture dialed in pretty well. I dunno….I've never considered adding catalytic converters to a car...hmmm?

 

[diesel_lv]

OK, I think your cam is reasonable & you have all the parts and I'm sure it will run fine. Thinking out loud on the exhaust, you might just think about some "hemi resonators". I've got stock-type Walker mufflers & have been considering splicing in some cherry bombs into the tailpipe area as a "cheap hemi resonator knock-off" or maybe some actual repro ones if they're not insanely expensive.

For the cats....they do reduce sound more than you would think. An obviously, they reduce hydrocarbons...but I'm thinking your fuel injection setup with have the air/fuel mixture dialed in pretty well. I dunno….I've never considered adding catalytic converters to a car...hmmm?

Thank you for the recommendation. I had actually thought of using header glasspacks then to the mufflers before thinking about catalytics, but resonators would probably be very good too.

 

[kiltedrunner]

Thank you for the recommendation. I had actually thought of using header glasspacks then to the mufflers before thinking about catalytics, but resonators would probably be very good too.

I have a similar build with a dual 3" exhaust and dynomax mufflers. While it sounds great idling and under load, I can't stand the drone while on the highway. I've been considering adding some resonators after the mufflers, but just before the exhaust tips.

Not sure if anyone has done this, but hoping it would help.

 

[dcala84141]

I to also followed that hot rod article to the T, but instead of the 231/237 cam I went with the roller thumper cam which I later found out not the best choice 527 hp at 5700 and 542 trq at 4400 Going to go with what I got for now and maybe change to a cam with less overlap next year

 

[68 HEMI GTS]

Run 3” TTI out the back with an x pipe. My car has no drone, even with the flow masters. Although if noise is an issue I wold recommend the dynomax super turbos that TTI sells with their kits. Be a very nice street setup.