Exhaust manifold selection?

[motorparts92]

Car: 1970 Coronet, 3700lbs,

My question on this thread has to do with Manifold selection for my 440. First of all, the engine is a stock 1970 440 HP engine, 9.7:1 pistons, Lunati Voodoo 268/284 .475/.494 Cam, Edelbrock performer stock style intake manifold, clean unported set of 452 heads with oversize valves and street hemi valve springs.. Basically a stock fresh 440HP with a little extra goodies. I was given a set of barely used Hooker Competetion headers 1.7/8 size tubes. I also have the stock 440 HP manifolds... I am inquiring that with the information given, what would you veterans suggest i use for my application? The problem i have with the headers is i am not able to use stock style starter, power steering, oversized torsion bars...and i just pondered if these would even benefit me with my heavy car and mild engine. What do you think?

 

[shag766]

the pure answer is the headers will help. what i don't get is if the car is original 440 motor why change the tq bars. maybe a mini starter is needed, no big deal. as for power steering i am not able to answer that but rest assured someone on here will be able to.

 

[Garys1969RR]

Headers are always going to offer less restricted exhaust flow, as long as you have an adequate ex system to go with it. But how much more power will you get? I prefer the stock H P ex manifolds on my 69 RR just for ease of installation, and trouble free service. Dont know if your headers will clear the P/S pump etc, but they should. I am always changing parts around on my engine, heads etc. So the manifolds make it alot easier to work on than with with headers. Good luck.

 

[motorparts92]

Headers are always going to offer less restricted exhaust flow, as long as you have an adequate ex system to go with it. But how much more power will you get? I prefer the stock H P ex manifolds on my 69 RR just for ease of installation, and trouble free service. Dont know if your headers will clear the P/S pump etc, but they should. I am always changing parts around on my engine, heads etc. So the manifolds make it alot easier to work on than with with headers. Good luck.

yes, i installed the headers already and ran the engine. They fit, but are pressed pretty tight up against my pwr steering, and when i drive and go around corners, it vibrates. Nevertheless, i am leaning toward the manifolds for the same reason as you...easy. Wont have to worry about burning wires, water seeping around those pansy header bolts, and everything will fit and function as it should. I just am trying to decide if whatever power increase i would get from headers is worth all the hassle.. I am not building a top fuel dragster, just a fun street car. I was thinking with the HP manifolds, and 3" pipes back to the mufflers, i would not be sacraficing a large amount.. thanks for the advice guys! keep it comin

 

[robinsonwr]

Well, I have many street/strip vehicles with headers. The current build is a healthy 440/512 stroker with .600+ lift hydraulic roller and 11:1 compression but will run HP manifolds. I will add a mandrel bent 2.5" or 3" full length exhaust. I do not want to worry about header or collector leaks.

 

[Garys1969RR]

I put fenderwell headers on my 68 RR years ago, and had nothing but problems. Leaks, hitting other parts, hard to work on. If you had a set that fit good, maybe ok. Like maybe TTY. I've heard good things about that brand, but not cheap. At least they clear the p/s parts, starter, steering etc.

 

[Meep-Meep]

My headers always fit with PS and stock starters so you must have something strange going on. Are your motor mounts in good enough shape and able to keep the engine at the proper height? Headers will make a bigger difference at high RPM, so if you will just cruise around and not worry about squeezing every ounce of power out of your plant then the stock manifolds are fine.

 

[72Satellite440]

I also didnt want to deal with mini starters/header selection etc.. and I picked up a great set of HP manifolds for 50.00 bucks..I started in last week and sounds awsome Went with 3" Flowmaster H pipe.

http://imageshack.us/clip/my-videos/232/dhy.mp4/

 

[64SF]

72 Sat 440. Sounds good. What engine mods?

 

[72Satellite440]

72 Sat 440. Sounds good. What engine mods?

4.15Eagle forged crank-eagle H rods-JE/SRP pistons-Indy Cyl heads-Indy dual intake--Milodan oiling/low pro pan..Compression ratio 11.35:1

 

[Dennis H]

Less weight and heat with the TTI's. My stock manifolds are for sale. 69 Coronet R/T.

 

[hendo0601]

As far as not wanting to mess with a mini starter i.e. price etc, just use the factory starter from a 93 Dodge Dakota 5.2L. It will bolt right onto your big block with zero modifications needed, and it is in a fact a high torque mini starter. You can pick them up for about 60-70 bucks at any parts store, and if you ever have a problem with it you don't have to worry about trying to get a warranty honored through a mail-order company like summit or jegs, just take it back to your local parts store. Just my .02

 

[62 Dart Convertible]

4.15Eagle forged crank-eagle H rods-JE/SRP pistons-Indy Cyl heads-Indy dual intake--Milodan oiling/low pro pan..Compression ratio 11.35:1

Car looks like a great sleeper - until you start the engine that is! That sounds so tough...

I would love to see back to back dyno results of an engine like yours to see just how much improvement headers provide over HP manifolds.

Surely HR or PHR mag or somebody over the years have done articles on this?! Anybody know of any??

 

[Sonny Black]

Sonny's 2cents---->Put headers on my rb block 63 b body.....also a GOOD air cleaner...it was a big difference in mid range power!!! also runs cooler, mini starter is high torque and it pops right over!(starts easy) BTW; TTI,H pipe, magnaflows and out rear.....

 

[Dennis H]

Sonny's 2cents---->Put headers on my rb block 63 b body.....also a GOOD air cleaner...it was a big difference in mid range power!!! also runs cooler, mini starter is high torque and it pops right over!(starts easy) BTW; TTI,H pipe, magnaflows and out rear.....

That's right. Lighter. Cooler.

 

[RustyRatRod]

Headers.

 

[q-ship]

With the cam you chose, and big valved heads, you are locked into headers.

Will it run good with manifolds? yes, but you have given up a ton of low end torque, so you NEED to get some of it back with headers and also be able to have it breath into the RPM range that the parts work at. manifolds are going to cost you at both ends of the power spectrum with your build.

I have to ask why you built for RPM if you wanted to use stock manifolds?