HP Manifolds vs TTI Headers ?

[BSB67]

1970 440 SIx Pack, nothing to crazy, on the dyno at 5500 rpm making 425 hp & 530 ft lbs of torque. I've always run original HP manifolds & factory H pipe, full exhaust. Is it worth it to install TTI headers ? Will it boost the horse power & if so by how much roughly ? Thanks in advance.

The answer will depend, at least to some degree, on the camshaft you are using. Do you know the specs?

 

[gtxrt]

Nick say's 35 hp more, and 60 more torque which is even more important. to get 60 more TQ with just one modification, what more do you want if more performance is what your looking for.

 

[gtxrt]

I ran the hedman Elite headers ceramic coated years ago I was wondering if they still make them. Never leak, thick flanges. They were 1 3/4 inches I believe. They fit nice, no mini starter back then.

 

[beanhead]

Answers: 1) yes it is. 2) yes it will. This is very simple : Factory exhaust manifolds are good for an original numbers-matching car. Period. How much HP ? It depends on your particular combo. I've run 6-bbl since the early 70's to this day. I'll put this out there right now... anybody that says the factory Exh manifolds are better, does not know what they're talking about . Period. Convenience ? Bull, I can change plugs just as easy on a 440 with headers as well as manifolds. If you can't, you shouldn't be working on cars. And I can do so as easily now, just as I did back then. That's my take. You do what suits you best.

No burned plug wires here.
That's a problem for people that allow that to be a problem.

depending on the headers and if they're ceramic coated or not, there's also the factor of under hood heat if that's a concern. If you do go headers, I'd spend the extra coin and buy the ceramic coated versions.

 

[Some Car Guy]

You’ll pick up a huge amount down low. That’s the win with headers. I’d run coated or not at all. Current car is a correct resto, I’d like to send the manifolds out for jet hot or similar. Would help with heat as my bay is packed with stuff to hold it in there. I’d love to see a comparison in the car of just coating manifolds. I’d bet a small amount of power and huge drops in temps.

I didn’t used to burn plug wires, but with uncoated headers I had the them break down quickly. Especially the ends. They’d look fine, but a nighttime start would reveal a light show under there. It’s pretty weird to watch as a perfect looking wire let’s a random spark out at idle. You can hear the misfire as you see it.

 

[super-bee_ski]

Answers: 1) yes it is. 2) yes it will. This is very simple : Factory exhaust manifolds are good for an original numbers-matching car. Period. How much HP ? It depends on your particular combo. I've run 6-bbl since the early 70's to this day. I'll put this out there right now... anybody that says the factory Exh manifolds are better, does not know what they're talking about . Period. Convenience ? Bull, I can change plugs just as easy on a 440 with headers as well as manifolds. If you can't, you shouldn't be working on cars. And I can do so as easily now, just as I did back then. That's my take. You do what suits you best.

Try replacing the starter on a Hemi in a Superbee with headers....
Can not be accomplished w/out removing drivers side header, which means dropping the Torsion Bar

 

[super-bee_ski]

Great post!

 

[WileE]

Try replacing the starter on a Hemi in a Superbee with headers....
Can not be accomplished w/out removing drivers side header, which means dropping the Torsion Bar

Been there, done that... and I'm talking 50 years ago. I've done jobs on cars that make doing that like a piece of cake.

 

[Butch Harley]

manifolds 1 not a drag car 2 more room to work!!!!!!!!

 

[casey henson]

One of the reasons I chose HP manifolds...

 

[64 Plan B]

1970 440 SIx Pack, nothing to crazy, on the dyno at 5500 rpm making 425 hp & 530 ft lbs of torque. I've always run original HP manifolds & factory H pipe, full exhaust. Is it worth it to install TTI headers ? Will it boost the horse power & if so by how much roughly ? Thanks in advance.

I’d have to say that new coated hedders look great , they will give you more power/torque (likely on the bottom end) and are worth every penny
I went with a mini starter after baking a couple regular starters and would recommend Remflex gaskets
Decent hi heat wires will likely keep you running on all 8 it you’re careful with routing
Good luck !

 

[6PK2GOBEE]

1970 440 SIx Pack, nothing to crazy, on the dyno at 5500 rpm making 425 hp & 530 ft lbs of torque. I've always run original HP manifolds & factory H pipe, full exhaust. Is it worth it to install TTI headers ? Will it boost the horse power & if so by how much roughly ? Thanks in advance.

The factory manifolds are actually nice pieces and flow 87% of full tube headers. With basic port matching that number can be raised into the low 90’s.
Hardly worth the cost changing to headers given the noise and heat generated by them for such a small gain.

 

[Cojohnso1]

Great post!

It was a nice and fair comparison. Those Max Wedge manifolds are big. And adding 30# total is not as significant than 50ft/lbs torque increase. Headers of course would be better. But not enough to justify the costs in my opinion. It was always the opinion that in a stock or near stock build. The HP manifolds flows enough. And seem to be more stable at different temps and conditions that I have noticed. On my 451 drag A-body. Those same hookers can be a challenge getting engine up to temp on cool Minnesota summer mornings. But the 451 is about 600+ HP build. Thus really was no debate. But I'm happy with the HPs on a near stock street 440 in my '69 GTX.

So in closing. The test between the 3 was pretty much what was expected.

 

[RemCharger]

The factory manifolds are actually nice pieces and flow 87% of full tube headers. With basic port matching that number can be raised into the low 90’s.
Hardly worth the cost changing to headers given the noise and heat generated by them for such a small gain.

While this is a fairly imprecise statement, even at 90% let's say, of an undetermined header, a 400 hp engine would be at 440hp with the headers.
So yes, the gain is miniscule.

 

[parksr5]

I ran a set of 1 7/8" primary Hooker long tubes, with 2.5" compression bent exhaust and Flowmaster 2 chamber mufflers. I ran it on a chassis dyno and the calculated flywheel numbers worked out to around 420HP and 520 ft lbs. The car ran a best of 12.25 on a drag radial. Switched to HP manifolds, mandrel bent TTI exhaust, with Dynomax mufflers and ran a best of 12.48 the next time out at the track, with similar weather conditions.

Not a back-to-back test and I had many weekends of racing to hit the 12.25 but, rough figures, the change was .23 in the 1/4 mile.

 

[33 IMP]

I ran a set of 1 7/8" primary Hooker long tubes, with 2.5" compression bent exhaust and Flowmaster 2 chamber mufflers. I ran it on a chassis dyno and the calculated flywheel numbers worked out to around 420HP and 520 ft lbs. The car ran a best of 12.25 on a drag radial. Switched to HP manifolds, mandrel bent TTI exhaust, with Dynomax mufflers and ran a best of 12.48 the next time out at the track, with similar weather conditions.

Not a back-to-back test and I had many weekends of racing to hit the 12.25 but, rough figures, the change was .23 in the 1/4 mile.

Interesting. That calculates to about 25 horsepower, about the average guess that headers would be worth. Yet most would assume the straight thru dynomax are better than the Flowmaster, and engine masters proved that mandrel bent means almost zero compared with compression bent.
I would be very curious what the mph difference was, and the race weight.

 

[68 Sport Satellite]

Interesting. That calculates to about 25 horsepower, about the average guess that headers would be worth. Yet most would assume the straight thru dynomax are better than the Flowmaster, and engine masters proved that mandrel bent means almost zero compared with compression bent.
I would be very curious what the mph difference was, and the race weight.

Yes, I think the mufflers made the difference. I run the straight through Dynomax Ultraflows and they flow WAY better than 2 chamber Flowmasters that were on my car before.

 

[Gus chiggins]

I used the hp manifolds. Ultimately it's your choice. To me the manifolds are less problematic.

 

[MCODECUDA]

The Fast Class cars don’t seem to suffer by using stock manifold although they run a lot of compression which forces the exhaust gasses out. My next stroker motor will use stock magnum manifolds.

 

[Gus chiggins]

Answers: 1) yes it is. 2) yes it will. This is very simple : Factory exhaust manifolds are good for an original numbers-matching car. Period. How much HP ? It depends on your particular combo. I've run 6-bbl since the early 70's to this day. I'll put this out there right now... anybody that says the factory Exh manifolds are better, does not know what they're talking about . Period. Convenience ? Bull, I can change plugs just as easy on a 440 with headers as well as manifolds. If you can't, you shouldn't be working on cars. And I can do so as easily now, just as I did back then. That's my take. You do what suits you best.

Ok, but what about changing the starter?