HP manifold differences

[Dino]

After pulling the engine I'm not too keen on putting the headers back on.  They worked great but I just have no use for them.  Unfortunately the hp manifolds are stupid expensive and I do need  to watch my spending, the car is going to need a lot as is.  Although the car is a 69, the engine is from a 71.  I still have the Chrysler TNT pie tin.  I thought about making the engine look like a 69 and I did get the water pump nipples a few years back for a 69 so I could run the stock heater hoses.  Then I thought what's the point?  It came from the factory with a 318 so who am I trrying to fool?  I've decided to redo the engine as it was in 71, or at least close to it.  The Sanden compressor will look a bit out of place.   

I found the driver side manifold cheap, part number 2951865, so now I need the passenger side.  I know there are some differences in the manifolds regarding the hookup to the pipes so I'm not sure which one to get.  It should be 2899879 but will this work?  At the moment I have true duals that fit the headers so I need new pipes.  Should I order them for a 70 then?

Also, I'm debating adding an H pipe and if I replace the mufflers they will likely be ultra flows.  I may want to keep the true duals though as I like the sound but if you guys want to talk some sense into me, I'm all ears.  I do NOT want an X pipe though.  This car is just a street car and I really don't like the sound they make.

[don duick]

 I had HP manifolds and switched to headers, now I am thinking of going back to the HPs. I think the right hand manifolds are the same. Any differences on the manifolds between 69 and 70 is on the left side only. the flange angle is the only difference. Why get a new exhaust ? you only need a short pipe to connect to your existing pipes. Unless you need new pipes. I definitely recommend you use a H pipe this will improve the sound.  I have dynomax VT mufflers they sound great and have no drone.

[Troy]

You should buy the opposite of the one I have and then trade me! Mine was switched prior to me getting the car and has leaked ever since due to the slightly different angle. I'm very tempted to just put headers on since I have a set of TTis taking up space for the last 8 years...

But as for making it look like anything, I wouldn't mess with it. Better to make it look like a 69. If you're not doing that then why make it look like anything specific? Use the parts that work and keep on driving.

Troy

[Brass]

Why change them if they work great?  Power *and* mileage will likely suffer if you switch back to manifolds. Unless they've been trouble, or you want the fast-ratio pitman/idler down the road, I would spend that money on an x-pipe with some ultra flos instead.

[71 SE3834V]

The casting number on my '71 pass. side ex manifold is also 2899879 so that confirms that (also in my '71 pdf parts file).

Having just dropped my engine in last fall w/HP manifolds and participating in pulling yours w/the headers (what a pain in the you know what!) I vote for the HP manifolds. I like I said in person, as far as the seat of your pants goes will you feel the difference? Any difference you feel will no doubt be in the positive direction because of the cam change.
My  

Oh, lemme add one more nugget of opinion.
Any money you spend on the HP manifolds will GREATLY reduce the time of the install! Bolt them on the engine while it's on the stand, drop the engine in and bolt the exhaust up while underneath doing all the other stuff. Well that's how it went w/my existing exhaust. I know it'll be a little different w/your pipes but you get the picture.
Maybe in a younger day but I getting too old to be F-ing with extra work crap when you just want to drive the car. 

[Dino]

Let me rephrase that...they work great as in there's nothing wrong with the headers.  I just don't like headers all that much.  I like the sound coming out of the tailpipes but that typical thin sound coming from under the front is what bugs me a bit.  Headers were fun on my 68 when I was in my twenties, but now I don't cae for them anymore.  The underhood temp is not bad so that's not a reason to get rid of them, the lack of space however...

The thought of wrestling those things back in is not one I care to see through.  Additionally the headers have surface rust and there's very little paint, if any, that will last on a header so the remaining option is ceramic coating and that's costly.  If I had a powerful engine and it could actually benefit from headers then we wouldn't have this conversation, but there's just no point in having these on my engine.  If there's anything I need it's torque and I'll probably do better with HP manifolds then  I realy don't care what this car can do at the top end as it never sees it.

Reasons for having manifolds: paint will stick to them and last, I can get a heat stove and hook it up to that 71 dual snorkel ar cleaner I have.  I do drive this car when it's freezing so these things are important.  This is not a car that ever sees shows or cruises but it racks up a few thousand miles a year, rain or shine, hot or cold.  And, as Jeff said, the engine will drop right in with the manifolds bolted in place.  These headers were indeed a pain.  And yes, it's the cam that will make all the difference, not the headers or manifolds.

The idea of havng the car more stock is appealing to me.  I really don't are for all the aftermarket stuff anymore.  I still love custom builds and all that, but having a mismatched part like headers on a low comp engine just doesn't make sense to me.

The exhaust pipes have surface rust but they're solid so adding short pipes indeed should do it.  I guess it won't hurt to add an H pipe, wasn't that how they came by the way?  I'm installing a cam closer to stock, a tad hotter but barely, so that's going to tone the exhaust note down a bit from the current purple cam, I suppose adding the crossover will also mellow it out which means I can get better flowing mufflers.  I'm not familiar with the VT mufflers so I'll check them out!  Definitely not getting an X pipe, I don't care how well they flow, I do not like the sound they make, never have.  Too raspy for me.   

About making it look like a 71, it's only because it is a 71 and all the parts I have are for it.  I have the 71 only intake manifold and the dual snorkel.  Instead of buying more stuff why not use what I have right?  Besides, the intake manifold is supposedly one of the best flowing manifolds Chrysler made back then.

Troy which manifold do you have and which do you need?  Who knows what I will find, we may both get lucky!

[Bronzedodge]

When I regasketed my 383 I had my exhaust manifolds surfaced.   A machine shop took .003 off of them to true them up.  There was never a gasket from the factory, so I put it back that way.  One less thing to leak or burn out.   

[john108]

These exhaust manifolds were off a 440.

[Dino]

When I regasketed my 383 I had my exhaust manifolds surfaced.   A machine shop took .003 off of them to true them up.  There was never a gasket from the factory, so I put it back that way.  One less thing to leak or burn out.   

That's pretty cool.  I had heard they came without gaskets but have a hard time wrapping my mind around that.  I'm assumig the heads wouldn't need surfacing as they are thick?

These exhaust manifolds were off a 440.

Yeah those are stock non-HP manifolds, aka logs.   

[justcruisin]

I took these off my 71 R/T if a pic helps.

[Dino]

I took these off my 71 R/T if a pic helps.

I just bought that driver side on today, now I need to find the other.      

Thanks for the pic.   

[don duick]

I just removed my headers and put on HP manifolds and took it for a test drive today. You are right Dino. there is no need for headers on a stock or mild 440. I have not felt any difference according to the bum on the seat dyno. Now has a deeper sound but same noise level.

[Dino]

I just removed my headers and put on HP manifolds and took it for a test drive today. You are right Dino. there is no need for headers on a stock or mild 440. I have not felt any difference according to the bum on the seat dyno. Now has a deeper sound but same noise level.

Excellent!  Nothing wrong with the deeper sound either.   

[71 SE3834V]

....... according to the bum on the seat dyno.

That's funny right there! I gotta remember that one.

[archie360]

Sticking with the HP manifolds here.  Had to replace the pass side which had a large crack.  Might even attempt to weld it up as it's not doing anygood where it sits.  Dino, I agree with you on the heated air ducted to the snorkel.  Really seems to help driveability when the engine's cold. 

[gcdsn76]

I have a 67 383 and I have a set of non-HP manifolds. Did they use studs or bolts? Does anybody sell a kit like the ones for the HP manifolds?

[don duick]

I have a 67 383 and I have a set of non-HP manifolds. Did they use studs or bolts? Does anybody sell a kit like the ones for the HP manifolds?

yes they also used studs. You can use the stud kit for the HP manifolds you will just need an extra 3 small nuts or have 3 long nuts sticking out. It might be cheaper to just buy 12 studs and nuts from summit or any bolt shop

[gcdsn76]

This there a Dorman part number for these studs?

[71 SE3834V]

This there a Dorman part number for these studs?

Dorman #673-003

http://www.oreillyauto.com/site/c/search.oap?keyword=675-003