Headers: Cheap or High Buck?
By Jim Hill
I read of the trials and tribulations some folks have been having with trying to choose a set of tube steel exhaust headers. I'm not a header expert, but I have been around enough to have learned a little about headers and exhausts.
Hedman Hedders have been discussed. They are very reasonably priced and are of equally reasonable quality. They're very good for few dollars.
However, the cliché "You get what you pay for" is very accurate when it comes to headers. Tube steel headers look like a writhing, twisting "bag of snakes" for a number of reasons. (Remember Indiana Jones' saying: "I HATE Snakes!")
Those twisting, winding tubes must be designed, jigged, and welded to clear all suspension, chassis, engine, steering, and accessory items. Other considerations such as spark-plug installation/removal also must be considered. Next, they should be as close to "equal length" in their primary tubes as possible.
Why? Equal length promotes more equal cylinder-to-cylinder efficiency.
Fit, flange squareness, and spark-plug accessibility are all critical considerations when buying headers.
As an example, have you ever struggled trying to get the plugs out of poorly fitting/designed headers with big-tube small-block Chevy pipes? I'm referring to 1-7/8" primary or 2" primary headers in race-only, high-rpm applications. Or, 2-1/4" or 2-1/2" primary headers in a big-block Camaro? Can you say: "Special home-made custom tools, skinned knuckles and hands sporting lots and lots of those little dark skin patches that come from header burns"!
Some of the lower-priced products might have to compromise these critical points to bring the product home at a reasonable price. Generally, lower-priced headers sacrifice equal-length or near-equal considerations for fit and low-price.
For a strictly street driven vehicle this may not be critical, but for a street/strip or pure-race application, equal-length and an absolute minimum of sharp bends (which restrict exhaust flow) in the primary tubes means added HP and torque... something you're seeking in any performance car or truck. If this is your goal, you may have to step up and pay extra for better-quality headers.
At one time Hooker offered the best quality in mid-priced headers. Their fit, finish and tube lengths were generally very good. I have no idea if this still holds true since Hooker was bought out by the new Holley conglomerate. If you're seeking the ultimate in race headers, I'd say it would be hard to find better than the headers made by Jack Davis. His "Step" headers are the choice of most of the strong runners in NHRA and IHRA doorslammer classes, especially in Super Stock. Expensive? You bet! A set of Jack's headers for a big-block '69 Camaro were about $1,200 (!), but we're talking about the ultimate headers for ultimate serious race cars.
I mention this just to offer some parameters in "low-end to high-end" comparisons for quality and price.
Another consideration is in the "behind the collectors" area. The "old" Chrysler Corp. (before the Germans!) did exhaustive research into race exhaust systems in the late 60's and early 70's. What they found was that the addition of an "H" shaped cross-over tube behind the collectors added mid-range torque with the surprising benefit of quieting the overall exhaust noise. It even made the system sound better to the ear. Back then, in the days of glass-pack mufflers, the engineers found the best performance mufflers were Chrysler Imperial mufflers and the Chevy "turbo" mufflers originally used on the turbocharged Corvair Spyder vehicles! (Yep, I DID say "Corvair!")
Today we have more sophisticated designs such as the "X" pipes and a wealth of HP-designed mufflers from Borla, Supertrapp, Flowmaster and others. Some of the magazines ran tests on these as a comparison. Surprisingly, muffled Super/Comp dragster and Super/Gas engines lost no HP with the addition of mufflers, and in some cases, gained power!
If you want to "bone up" on racing/performance exhaust systems there are several good books available that offer a wealth of information. Motorbooks is a good source for these titles.
Another consideration to give serious thought to is header coating. Simple header paint is certain to burn away. Some engine builders prefer to use the coating processes, not only for appearance but to insulate some of the exhaust heat. Remember, that motor is just a "big heat pump," and heat means "work." Header insulation wraps also prevent excessive under hood temps and fuel handling problems. They also insulate the driver from heat, not critical in a drag racing car as much as in an endurance oriented oval track or road race vehicle. Again, thorough research and investigation could mean saving some bucks and adding some HP using good ol' common sense.
I'm sure the old-timers are aware of the points I've made, but for those just getting their feet wet building a car, this might save wasting money and time buying two or three sets of headers to get the best for your own application.
Trust me, there is considerable HP and torque available in a "max" set of race headers over an inexpensive, street intended product.
Like esteemed oval track chassis builder Banjo Matthews once said: "Speed costs money, son. How fast do you want to go?"
Jim Hill
www.cranecams.com
