Headers vs oem manifolds

I have driven my 32Pacearrow 460 now....just put new manifolds on it and a true dual exhaust with big walker muffs...pulled hills near by at least 10 miles/hr faster, and in the 90 degree heat a lot less temp on the gauge ....PLUS I installed two fresh air vents 4inch from the front to on top of the manifolds.... cut two 4 inch holes above my headlights , used 8' aluminum dryer vent hose , routed it around and pointed it to my manifolds.Even climbing at 45 there is now normal air in my engine compartment.....and air at 45 MPH force.....

There are a lot of junk headers on the market. Stainless headers are not a necessity but coated headers are. What you are looking for in a header is a thick head flange, thick and preferably ball connectors at the collector and a ceramic coating, coated inside and out. Do your home work and make your decision. Not all coated headers are coated inside the pipe.
Randy

Free flowing exhaust or headers do wonders for engine power, in most cases.
One thing you will appreciate is buying or making heat shields to keep heat from the exhaust from plugs and top of engine and the rest of the engine and compartment. Properly sized mufflers and real dual exhaust will help too.
Larger oil coolers are a must also with a thermostat.

WILDEBILL308 wrote:

Banks, Thorley and Gibson are all designed to provide lower end torque and horsepower. All 3 use a “long tube” header designs. If you are concerned with under hood heat go with the ceramic coated ones or wrap them.
Bill

Have you ever seen a Tri-Y? 2 cylinders combine a little over a foot away from the port. The cylinders that combine are at opposite ends of the firing order. These combine into a tube that is the same size, which then continues down to the collector.

the Tri-Y design "Primaries" are very sensistive to "tuned length"
and the 4-1 design is opposite, ..very sensitive to Collector more than Primary Length
the Tri-Y has a negative pressure wave at the Branch and again at the collector and again at the Collector exit, the design keeps velocity up through out the system and pipe surface area is relatively small to radiate less heat and keep velocity higher

This is from a guy who has done 1000s of dyno tests to prove out simulation software accuracy. (not someone who is trying to sell their brand of header)

Please do a Google search on Tri-Y vs long tube. They are very different, and there is plenty of good info as well as dyno tests that show how Tri-Y has a much wider power band than long tube.

WeBcruisinc wrote:
Seems to me that the majority favors a header system over the OEM manifold. I also see a lot of support for the banks system, It is expensive but I've pretty much made up my mind to go with it. Now I just need to save up a few more pennys to finance this deal.
Thanks folks for your input. I will update when we getr done.

You are doing the right thing, by going with Banks. Their system is engineered specifically for RV use, using the best products.
I installed Banks on my 454 Chev, and it was everything they said and more! More power, ran cooler and much better drivability throughout the entire power band.
GO FOR IT!

Daveinet wrote:

WILDEBILL308 wrote:

You may want to do some more research on that stamen. Banks, Thorley and Gibson are almost the same design and all work well for a motor home.
Bill

Every bit of research I have been able to find that compares Tri-Y to long tube headers shows the Tri-Y perform much better in the midrange, as well as the "low" top end. Look at any Dyno graph comparison, and below 4500 RPM, the Tri-Y out perform long tube on the same engine, same test. Basically the wide RPM boost starts in the low mid, and carries out to above 4K. My seat of the pants also confirmed this, once I finally got decent mufflers. There was a huge boost right out of the hole.

I'm am a little curious that you state that Banks, Thorley, and Gibson are all the same design. How can they be the same when one is Tri-Y and the other is single long tubes?

Banks, Thorley and Gibson are all designed to provide lower end torque and horsepower. All 3 use a “long tube” header designs. If you are concerned with under hood heat go with the ceramic coated ones or wrap them.
Bill

My ceramic coated Thorleys fit as tight as OJs glove.

I installed a new set of Thorley Tri-Ys on my 454 P-30 in April.. When they came they looked great, but I have habit of checking out all parts before installing.. When I put a straightedge on the header flange I found it was warped from the welding process about 1/8" to 3/16". Instead of sending them back to the left coast and waiting a couple more weeks, I took them to a neighborhood machine shop and we put them in the hydraulic press and pressed the flanges straight, and then used a large 30" horizontal belt sander to sand them perfectly flat.. There was minimal material removed, but the moral of the story is that if I had put those new headers on like that, They probably would have eventually leaked too.. The Thorleys really helped on performance and heat removal..

There are definate advantages to headers... NORMALLLY I would not recommend the Banks or any other header with the possible exception of Ultra Power because I do not feel you will ever recover the cost..... NORMALLLY.

However yours is a special case.. In your case you are already replacing the manifold, so the labor cost for installing headers approaches zero, and the cost of the new manifold is deducted from the cost of the headers and that very likely cuts the cost down by over 50%..

I'd say GO FOR IT.

WILDEBILL308 wrote:

You may want to do some more research on that stamen. Banks, Thorley and Gibson are almost the same design and all work well for a motor home.
Bill

Every bit of research I have been able to find that compares Tri-Y to long tube headers shows the Tri-Y perform much better in the midrange, as well as the "low" top end. Look at any Dyno graph comparison, and below 4500 RPM, the Tri-Y out perform long tube on the same engine, same test. Basically the wide RPM boost starts in the low mid, and carries out to above 4K. My seat of the pants also confirmed this, once I finally got decent mufflers. There was a huge boost right out of the hole.

I'm am a little curious that you state that Banks, Thorley, and Gibson are all the same design. How can they be the same when one is Tri-Y and the other is single long tubes?