Headers on late model trucks

powerisfun

Just curious if anyone whose added headers to
their late model truck (late model meaning '90 or
so to present) could share their experience with me
and others. Were they worth the price? Were they
shorty headers? Was there a noticeable
performance improvement? From what I've heard
there is a tendency for headers to shift the torque
to higher rpm's which may not be what a truck
owner wants (particularly if towing or hauling
often). I'm particularly interested in other
'96-'99 GM C/K trucks with the 5.7L engine, but I'd
be interested in all makes and models.
I already have mine, but haven't yet installed
them (hopefully in the next few days or at least by
this weekend I'll get some time). I'll post my
own experience in future messages. In the
meantime, I'll direct you to a great website that
has a bunch of performance modification data for an
'88 Ford F350 (including headers, cat-back,
computer chip, 180 thermostat, synthetic fluids,
etc.) . The site is
http://www.performanceunlimited.com/projectmpg

If you're adding bolt-ons to your truck, this is
definitely a site you'll want to read.

-powerisfun

dave40

Your Truck engine is a big air pump. The more air you pump out and the more you pump in make power. Headers, catback exhaust, High flow air intake systems will make a Big difference. Shorty headers work best with under 400hp engines. Use the long tube headers for over 400hp engines plus they are more time consuming to install on the new Vortecs.

z71brent

You can get headers that actually increase more in the low end of the band than the mid to upper end of the power band. All depends on which brand and type you buy.

"IF or When" I put a header on my truck, it will be a JBA or Jardine". They are the best in the business for low end torque. They are high sellers in truck and RV headers and exhausts.

The ceramic coated shorty headers for the 99 Silverado 5.3l are $675, but well worth the investment if you ask me.

powerisfun

What is the advantage of ceramic coated headers over just plain painted headers? Is it a looks thing, or is there a performance reason?

powerisfun

dave40

Ceramic lasts longer and don't get as hot.

powerisfun

After installing the PaceSetter headers, I noticed that there is a little more in-cab noise compared to the stock manifold. Not enough that it's a bother, but it was enough to make me believe that there may be something wrong.
Anyway, due to pathetic quality, I'm sending the PaceSetters back to JCWhitney. The pathetic quality I'm referring to is not the noise, but that the welds were sloppy and unprofessional looking, the bolt holes didn't line up quite right (one of the header bolt-heads was scraping on the primary tube next to it, and one of the head-pipe bolts would not go in in the correct direction, I had to put it in backwards.), the EGR tube didn't seal correctly, and the paint-job was deplorable. I should have just sent them back immediately rather than waste time installing them, but much of the poor quality didn't rear it's ugly head till after they were already half-way installed. Now I know better, what to check, what to look for in my next set. I've ordered a set from Summit Racing (their own brand). They're a much more trustworthy name than PaceSetter.
Once again their just painted instead of chromed or ceramic-coated, but then again, they're only $160 compared to $350-$600 price range for the top name brands. Even if they wear out in a few years, I can just install another set and still have less invested. Summit claims their brand is tuned to give the most torque and horsepower gains in the 1500-3500 rpm range. Right where I want it.
I paid the $7 for two-day air and they shipped them today, so they're guaranteed to be here by Thursday. We'll see. I'll install them this weekend and let you all know how they compare sound-wise and performance-wise to the PaceSetters. Oh, the PaceSetters did seem to produce more power when you step on the pedal (i.e. 2500 rpm or higher). That is the only positive thing I have to say about them.
I also have a split-rear dual exit cat-back to install and I should have that installed this weekend as well.
-powerisfun

powerisfun

Needless to say, you should avoid TFX-PaceSetter products like the plague. This was not one simple thing that I was just fussy about. I kept giving them the benefit of the doubt, but they kept getting crappier as I kept installing them.
-powerisfun

2sly4u

You may actually get "LESS" hp and torque from a non-ceramic or chromed header than you would by just leaving the stock exhaust manifold. The heat soak you are going to experience is definitely an adverse factor, especially in these new Silverado trucks. They run way too hot already. Add the extra heat from a cheaper header setup and you are just asking for problems.

Trust me, the extra money for the ceramic coated headers is well worth the cost. I would leave the stock manifold before investing in a cheap header, at least on these heat soaked, power robbed new model Silverado's.

Not just my opinion. Many will tell you that there will be just way too much heat in the engine compartment and there is already a problem with these trucks running way too hot.

Best of luck.

powerisfun

Actually, my truck is a '98 GMC with the 5.7L engine, which I believe runs a little cooler than the new trucks (not as high revving), but your point is still well taken. They sell header tape to insulate the tubes for around $25.00. That should be even better than a ceramic coating to keep the heat in. That should also help insulate the sound now that I think of it.
Any experience with header tape?
One other thing is I'll be ordering one of those fancy hoods with a hood scoop in a few weeks. That will definitely help keep it cool in there.
Thanks again.
-powerisfun

2sly4u

Most header manufacturers void the warranty on their headers if you use the header tape.

I wouldn't use it anyway because it looks terrible. Ok for a race car at the track, but not for a $30k truck.

You are correct though. You probably won't have much problem. The previous model GM trucks run about 20 degrees cooler than the new model trucks.

powerisfun

I noticed on the Summit website that the tape voids the warranties, so I asked the Summit tech people why. They said it was because moisture gets between the tape and the header and causes rust. It's probably not as big a problem out here in NM where the humidity is a constant 25%, but I'll have to think about that one. I'm not that concerned about the looks. The looks of the Vortec 350 are very plain anyway and nothing to show off. The Vortec 454 and the new engines are much more attractive.
Maybe I'll just construct a little heat shield out of some aluminum or sheet metal till I get the hood with air scoop. Those hoods are pretty nice, by the way, and can be seen at (look at the "Customer Cars" section to see a better example than the ugly truck they have on the home page):

http://members.aol.com/Carbon4U/index.html

They don't yet have any advertisements for the new body style, but if anyone is interested, they can email them. They've responded very quickly everytime I emailed them.
-powerisfun

powerisfun

JBA Racing has some nice articles reprinted from magazines that tested their headers, etc. I'm always a little leary to take what the magazines say as gospel, because sometimes I get the feeling the articles are just paid advertisements. They make for interesting reading, though, and who knows? Maybe they're on the up-and-up.

http://www.jbaracing.com/trucksuv/truck_suv.htm

-powerisfun

powerisfun

...if you have a '99/'00 Silverado/Sierra, I don't think I'd bother getting shorty headers. In one of the above-mentioned articles, it shows a picture of the stock exhaust manifold removed from the engine and it looks very unrestrictive (a lot less restrictive and better designed than the stock manifold on the Vortec 5.7L). It looks like a well designed manifold in that it looks a lot like a shorty header already, so it probably has the similar siphoning (i.e. scavenging) characteristics. Unless you can find a set of smog-legal long tube headers (lots of luck there!), or you just want the look, I wouldn't waste the money.
-powerisfun

2sly4u

I agree with you on both of your last two posts.

powerisfun

Well, I got the Summit headers in on Thursday last week and I installed them on Saturday with no problems. Incidently, the Summit headers are now actually Flowtech brand headers which is what I wanted in the beginning but they were listed elsewhere as about 30% more expensive than the PaceSetters. They're definitely a better quality header than PaceSetter. Everything fit well and installation was very easy (especially after having installed the PaceSetters). Both PaceSetter and Flowtech need to work on their directions though. Both of them were very cryptic with no pictures. I didn't really need them (except to read through them once to make sure there wasn't something out-of-the-ordinary in them), but I'm fairly experienced with working on cars. I can imagine a new do-it-yourselfer would have been confused by them.

There is still a bit more cabin noise and I think it's because the passenger-side collector runs very close to the fire-wall exhaust shielding causing a resonance. The sound is only noticeable at idle and it just sounds like exhaust gas rushing through a tube (kind of resembles the sound of coffee brewing). I can live with it, but I'm going to try to put some kind of heat-resistant sound absorber between the fire-wall and the shield (don't know what yet) just to see if it helps.

The power is most definitely better. This was the first time that I've actually driven it for a full 26 miles. I have a very good testing ground available to me. I live in a mountainous area and I have to travel up a big hill every day to work. The hill is a 9% grade that goes up for 1.5 miles with some tight turns. In conjunction with the the 7000 ft. altitude, even sports cars get bogged down. Anyway, I always climb it by shifting down from overdrive into drive at the bottom of the hill at 60 mph and I don't allow it to downshift further (never really needed to). Doing this my previous top speed was always 60-62 near the top (with an rpm of about 2450). With the headers, however, my top speed was 66 near the top. Further, I started out slower at 55 at the bottom of the hill instead of my usual 60 because I ended up being boxed in by traffic. I'm VERY pleased and impressed with the power difference. I highly recommend Flowtech headers (Summit) for anyone with the Vortec 5.7L (or the 5.0L for that matter).
I can't wait to install my dual-out cat-back exhaust. That will uncork it even further and should give it a nice sound. I wanted to install it this weekend, but I also didn't want to miss out on spending some time with my wife. Plus, I was interested to see how the headers by themselves performed on "the hill".
Later,
-powerisfun

powerisfun

Well, yesterday I installed my JCWhitney dual-out cat-back exhaust for my truck and I'm really pleased with it. For starters, it appears to be a very high quality system with PERFECT mandrel bends and nice looking welds on the muffler (The mandrel bends on the original GM exhaust are absolutely awful in comparison). It's all made of aluminized steel and I further coated it with a layer of high-temperature paint.
All the pipes are 2.5" diameter on the new system with a dual-in (GM has two cat-converters), dual-out (split rear exit, looks great!). I was worried that the larger diameter pipes combined with the dual-out configuration would hurt my low-end torque, but that's not the case at all. The muffler is a straight-through design that doesn't stop or change the direction of the gas, so that must help prevent the low-gas velocity that robs low-end torque. It's a big muffler (24 inches long) which helps with the sound even though it's a straight through design.
The sound is what I'm most pleased with. It has one of the most pleasant exhaust tones I've heard--a very low bassy grumble that's not the least bit offensive. Very quiet for cruising, but step on the gas and I swear my engine grows another 104 cubic inches. That goes for power too. The power is definitely noticeable in the seat of the pants feel. I think the headers and the cat-back really complemented each other.
This was all done on a budget, by the way, I paid a total of $361 including shipping for both the headers and the cat-back and installed them both myself. I still have to send the first (defective) set of headers back, but JCW is very good about that sort of thing.

For new readers that may be interested, my truck (that is, my "Z71 SS") is a '98 GMC Sierra SLE ext. cab (3rd door) with the Z71 package, the 5.7L engine, and 3.73 gears.
I've added:

K&N filter ($70 with cleaning kit)
Home-made cold-air/ram-air induction (~$35 total)
Halo Spark Plugs ($42.00 for eight)
Flowtech shorty headers ($181 with 2-day shipping)
JCWhitney SilverStreak dual-out cat-back exhaust
($180 including UPS ground shipping)
Cover Craft hard tonneau cover
($425 with shipping)

I love this truck, and my name is particularly relevant now.
-powerisfun

bluebeast

Why then does every magazine article that puts headers (JBA) on the 99/2000 Silverado 5.3L show a HP increase/Torque increase ?? 2nd, why does all the speed shops ASM, STillen, etc put them on then?? I will agree that some cheap designs and materials may decrease or have no affect, but for the most part you WILL ALWAYS gain hp/torque.

powerisfun

I'm not saying they won't work. I'm saying that the existing exhaust manifold for the 5.3L looks very unrestrictive and very well designed. It may be true that they do work great for the 5.3L without any low-end torque loss, but I'd doubt it.
Also, be VERY wary of any magazine articles about bolt-ons. I've read countless of those articles and most of them sound as though they're paid advertisements. Notice that they almost never say anything negative about the performance obtained or the products themselves. They can't all be that great.
One last thing, these articles that you quote, do they provide a complete torque curve with and without the headers?
-powerisfun

meredith

As a result of 30 or more days of inactivity....

this topic is being "frozen". It will be archived or deleted in the next 10 days or so.

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