Headers VS Manifolds

-
66cuda

66cuda

2011Armada K of C 1st PL
Joined
Dec 1, 2005
Messages
1,083
Reaction score
31
Location
St. Clair Shores Michigan
OK....here is the background... My 66 started life as a /6 car....because of its survive-ability( pretty much zero rust) it was deemed to become something greater. So Off I went to find a 340 block...found one...looked for x heads...found big port U heads...I am OK so far....cleaned it all up did the heads did the block and ran it through an assembly process....ALL GOOD....( so far) Found a failing 727 snatched it and started to pump it up...went from 3 to 4 clutch drum & clutches, 3 to 4 planetary s...ohh rah ....starting to come together.... found a 8 3/4 sure grip with a 355 cleaned it up and re-set everything...its tight and solid. found 3 v8 k frames, 2 were junk and the 3rd seemed to vaporize along with its owner ( I think he left Michigan.) Gave up on that and went with shumaker conversion mounts and stiffer torsion bars...there isnt that much difference in weight so...off we go.... OK now so the set up is /6 k frame, schumaker conversion mounts and a 727......had to modify the trans mount the stock one is about 2 inches too tall and the 727 hits the tunnel...drop it down 2 inches and off ya go...... I talked with TTi and they understand the config and say their headers will work.....IF I modify the trans cross member, the brake lines and block and use an expensive mini starter which assumes I have a regular torq converter ( which I do not running 2800 stall)..... SO the TTi's cost around $900 and then there is the $200 starter and a flurry of R&R to install not to mention it will ALL fit like skin ( meaning WAY TIGHT) in pretty much every aspect....... so here is the questions

1. Is the "performance" (and I mean REAL performance,) obtained from headers going to be worth the $1200 cost?.....

(I am not in bracket racing or any other kind of racing.....I want to burn out here & there....and nail it on occasion.....quite frankly I did not spend all this time building this thing up and restoring it only to beat the hell out of it.)

2. SURE I like to go fast but am I REALLY going to notice 10 to 20 horses? not at the clock/strip...but the pull felt behind the wheel??

3. so does anyone have a setup like this?
( OH I have the stock 273 v8 exhaust manifolds and cant seem to find if there is a difference between the 2bbl v8 manifolds and the commando v8 manifolds???? but I have to believe they are as big as the 318 ( never saw any 318 manifolds to compare))

I am leaning toward the manifolds for a couple of reasons....
1. COST
2. COST
3. Hassle ( modifications, installation & maint like oil changes etc)

so WHAT say you? and please provide some background and reasons for your statements....I am interested in your thought behind your comments
thanks
66cuda

headers? or manifolds?
 
1. Depending on your build the difference between headers and manifolds can be small or very large.

On my build for example…… I lost 1.42 seconds and 8 mph in the 1/4 mile (this is mostly exhaust change related but other factors, Im sure played into this). My build is not typical….. The engine set up is high compression and high RPM, the worst scenario for switching back to manifolds.

2. I look at it this way…. You have not driven the car with drive train you have built so you won't notice the loss…… The first time you run it is, what it will be.

Again, my personal example…… My car was fun and fast with headers and it is still fun and fast with manifolds.

3. If you go manifolds, you should at least run the best flowing manifolds that will fit your application.


My advise…. Go with manifolds, get it on the road and enjoy. You can always put headers on later if you feel the need.
 
If you want the max. performance from you build(340,X heads)I would run headers.The 273 manifolds on a 340 will restrict the full potential.Just my opinion.:read2:

P.S I scored a brand new mini-starter from a 89 318 Dakota at the local pick and pull.It was the best money saved on my build!$$$$
 
Header are worth it performance wise,and done right with good gaskets etc they will not leak(very much,lol).I would say that headers should be part of any performance build.Leave manifolds for the cruisers and restoration crowd.

If cost is your objection there are very reasonable headers out there like summit ,hedman etc. Mid grade cost would be hookers.

That being said NO header is easy to install. They will all require some work,like shifting the motor around,dinging tubes,maybe a smaller starter etc.
 
This will be a very subjective thread. Interesting too.

Really comes down to what you need from your car to get the thrill. Im at a 13.2, 1/4 through manifolds, in full street trim and on stock tires. I have no doubt that I could touch the 12s if i play with it and learn to launch better on the E70-14s.

The car does everything I need it to do for giving me that rush of excitement when I'm out for a drive.

Like others have said… If you are strictly looking to maximize performance, headers should be part of your plan.
 
Here is a link to a Mopar Muscle OEM manifold and headers comparison on a dyno using a mild 360. The more performance you build into the engine, the better headers will work.

http://www.moparmusclemagazine.com/...pp_0307_mopar_crate_engine_exhaust/index.html

But I may have some bad news.....Watch for other problems if you had to lower the trans mount location. If everything is tilted down at the rear mount, it will mess up your driveshaft/pinion angles and can cause header clearance issues with the chassis! Too bad you couldn't have found a 904 because I don't believe 727's were available in A-bodies back then, so the floor pan and frame wasn't designed to make them fit right.
 
WELL the engine was scoped on a bench and turned like a real 323 HP...pretty impressive BUT certainly not in the 4, 5 & 600 ranges where the experiment says the most can be obtained from headers....it is likely this car will never see a drag strip or be in ANY speed competition. With this one I will be burnin out here & there but that is about it...this is a drive park & shine toy. I ALREADY have a nine second yes 9, blown 340 72 Duster...so obtaining performance is no biggy and not a NEED with the 66.... and I have a crusier a 428 67 Pontiac Bonneville convertible.... this is just another toy ....just wanted to hear your thoughts/ opinions.... The set up is weird and it has all the right equipment, it actually looks quite stunning in the build phases...... I have just never realized the advertised and popular opinion benefits regarding the addition of headers on below 350 hp cars!! I have done many many installations and have yet to feel any significant difference worth the cost or effort required to put them in and maintain them....on the full blown race car YES I get it and I am lookin for 10'ths of seconds there but on the street???? The wrong activity there gets your car impounded, generates insurance coverage loss and hundreds in fines & fee's.....no thanks
It seems to be a somewhat senseless( to me) cost vs benefit arrangement. and I was askin to hear what you all would do with this sweet 66 if you were in my shoes and the money was coming out of your pockets....I hope it keeps going I am loving the ideas and the thoughts behind them



ANYONE know for sure if the all the 273 manifolds were the same? I was wondering if the Commando 273 were any different?
 
The 273 manifolds will choke your 340.
If you are going to run manifolds step up to some HiPo 340's.
Yes,they have gotten pricey,but they work real well.
 
I have talked to Ebay stainless header customers that say they are very happy with the headers they bought. Since they are designed as a replacement for the stock iron truck manifold's, they may work well for us A body types in milder apps!

http://cgi.ebay.com/ebaymotors/94-0...r_Truck_Parts_Accessories?hash=item3ef9b08180

I have a stainless header from ebay that I'll be installing on the neon pretty soon. A report will be forthcomin.
 
some people have had good luck using early durango dakota exaust manifolds as long as its manual steering floor shift in an early A-body dont flow as good as headers but better then stock 273 manifolds look for part # 53006618 & 53006619
 
I have a set of 340 TA ( HiPo) Manifolds commonly referred to as the "manifold header" they were mocked on the motor and do not fit the application..... they hit hard and bind the manual steering coupler on the drivers side and they dump directly over the torsion bar on the pass side..... they will be up for sale soon. 28635438 pass and 2863553 Drvr ..... They DO NOT fit a 66 with a /6 k, schumaker mounts and a 340 with a 727 behind, not even close!
When you say they will CHOKE the 340 what do you mean? nothing flows like a header I get that....but the 273 commando did pretty good out of the box and that is essentially the same LA motor as the 340 ....a lil bigger valves and point or two of increased compression true, but not that far off, they are pretty much matched HP for HP

273 Specs from a FABO forum called 273 specs

......................Charger/Commando................D/Dart
Horsepower...... 235 @ 5200 ......................275 @ N/A
Torque............ 280 @ 4000 ...........................N/A
Camshaft I .......... .425" .............................. .495"
E ....................... .425"............................... .505"
Duration ................248º.............................. . 284º
Overlap ..................46º .................................N/A
Carburetor..... 625 cfm AFB....................... 750 cfm Holley
Exhaust........ cast iron manifolds............... headers by Doug
Warranty........5 yr/50,000 miles...................... NONE

340 specs quote from ALLPar

The 340’s best power rating was 290 horsepower; even in 1973, it still managed 240-245 net horsepower.

ONLY 60 hp loss on the liberal side for not spending over $1200 is kinda acceptable and actually more like maybe 30 to 40 tops.....I can live with that.....

OK so the truck manifolds...... are they more "open" than the 273 manifolds and what modifications are required? even with manual steering there is NOT much room on either side , but it is pretty tight on the Drivers side do they feed straight out the back, then down? anyone have pics of them IN an early A?
 
Dave....you are using the stainless header on a NEON?...all good but how does that relate to using them on a 66 with a v8? I missed something in your reply??? do you know someone that used them on a 66 barracuda, Valiant or Dart with a v8 340, 318, or 273 engine and a 727 trans that was never designed to be in this narrow wonder?
 
66cuda
For a daily driver/cruiser there is no reason you can't stick with the manifolds. I have a mild 318 in my 65 valiant and i'm planning on keeping the manifolds but upgrading to the 2.5" TTI pipes that bolt right up to the manifolds and go all the way back (the only mod you need to do is notch the tranny crossmember, as you already know). The complete H-pipe kit with mufflers is about $600 which is really reasonable actually (they're aluminized mandrel bent and comes with all hangers/brackets). You can't have custom exhaust made for much cheaper imho.

The next less costly option is to buy a set of spitfire headers (~$225, but only using manual steering box) and have custom pipes bent to the TTI's.

Good luck!
 
I have been test fitting a set of Spitfires for my 64' w/ a 318. The fit lloks good so far and they will sure flow better than the stoke manifolds. The stainless headers listed above look pretty interesting. From the supplied picture they even look like they will work. Does anyone know anything about this mod? I would like to give it a try!
 
coolbreeze said:
I have been test fitting a set of Spitfires for my 64' w/ a 318. The fit lloks good so far and they will sure flow better than the stoke manifolds. The stainless headers listed above look pretty interesting. From the supplied picture they even look like they will work. Does anyone know anything about this mod? I would like to give it a try!
Click to expand...
any feed back on these, will they fit early A s ?
 
I'd like to see some pic's of the t/a 340 manifolds that you have.....something don't sound right there, i had 340 manifolds on my 64 dart convertable back in the day and I remember they fit awesome,you will have to have a 90* oil filter adaptor with them.
 
The more I look at the stainless headers avertised for a Dakota truck, the more I think they will work on a Early A. Does anyone run truck manifolds on their early A now?
 
Those stainless headers look very close to the Spitfires,but will the steering coupler have problems hitting?I know I had to ding mine in abit for clearance with manual steering(sold now).I,m also interested to see if the Dakota manifolds will work in a Early-A V8?
 
Ok out of curiosity went out there and sat the 340 manifolds on my 64 dart convertable. They fit right on there...will not work with power steering but manual steering.....no problemo
 
waggin said:
Ok out of curiosity went out there and sat the 340 manifolds on my 64 dart convertable. They fit right on there...will not work with power steering but manual steering.....no problemo
Click to expand...

I'm guessing that the passenger side fits fine and that it's the short length of the center shaft and/or the coupler for PS that interferes with the driver's side manifold. Is that correct?
 
66cuda said:
Dave....you are using the stainless header on a NEON?...all good but how does that relate to using them on a 66 with a v8? I missed something in your reply??? do you know someone that used them on a 66 barracuda, Valiant or Dart with a v8 340, 318, or 273 engine and a 727 trans that was never designed to be in this narrow wonder?
Click to expand...
the ones on the link are
94-02 99 00 DODGE RAM 1500 5.2/5.9 V8 STAINLESS HEADER might fit love to find out,
 
Waggin, does your car have a /6 K frame and uses schumaker mounts? I have manual steering and the drivers side hits and binds the coupler..... the pass side dumps right over the torsion bar and it would take a welding magician to snake a pipe in there..... I understand your doubt ( sort of ) but WHY would I provide inaccurate info? I am seeking assistance and opinions
 
To my knowledge,the exhaust ports on the 273 are around the same size as a 318 head. Much smaller than the exhaust ports of a 340 head.So using the smaller 273 manifolds would not let the motor breath to its full potential,or choke it.

PS: Never pay $200.00 for a mini-starter...$25.00 max at a junkyard.My last one cost me $12.00.

Thats to bad you cant get those 340 manifolds to fit,those would be the ticket.
Seems I have seen them on early A's ?
 
You must log in or register to reply here.
-

Back
Top