Headers

**barkster** · 6-25-04, 21:54

I know this topic is old... but, so are most of the posts.

I need to replace the stock headers in my 93 LS... they are rusting. And after all I've read on this subject here and on PT (and all the new product developments... gen III, gen IV, etc...), I'd welcome some fresh recommendations.

I understand the physics and all the talk about scavenging, pressure waves, flow, and so-called "backpressure"... good, bad, or otherwise. Do I want to lose torque? No... but I'm not looking to gain any for the moment, either. What I'm after for now is mid-to-top RPM performance boost.

I've seen the web pages for Borla, Bosal, Hotshot, Pacesetter, and others.... I'd like to hear more about your knowledge and experience with any specific brands on the following points:

base materials (mild vs. stainless)
coatings (ceramic vs. heat paints)
Fit and leaks (is it always hit-or-miss?)
flex pipe vs. ball joint vs. fixed (mid pipe)
welds and additional fittings required (if any, for a 93 LS)
2.25" vs. 2.5"
recommended additional thermal wraps

What, if anything, is really wrong with the OEM headers?

Thanks,
Glenn

**megamx6** · 6-28-04, 14:34

Usually aftermarket headers will flow more...as the stock narrows at the flanges...I have thermal wrap on mine but Id say all that does really is keep the heat from destroying your distributor and starter

**skiingman** · 6-29-04, 0:42

Quote:

Originally Posted by megamx6

Usually aftermarket headers will flow more...as the stock narrows at the flanges...I have thermal wrap on mine but Id say all that does really is keep the heat from destroying your distributor and starter

There can be significant power gains in controlling the loss of energy in the exhaust. You want the exhaust to be as hot and high energy as possible, so that your careful tuning causes the very lowest pressure pulse possible near the exhaust valve when it opens. If you let the gasses cool down, they are less effective in this regard.

Practically, you are 100% right about what a good idea it is to keep the disty and starter cool.

**Brad** · 6-29-04, 3:50

about the question - i have pacesetter and they work fine. dont know about the power increases though because i put them on along with every other mod i have at the same time. but the crafstmanship was decent and i dont have any leaks yet. it's been a little over 2 years

**skiingman** · 6-29-04, 10:42

Quote:

Originally Posted by Brad

about the question - i have pacesetter and they work fine. dont know about the power increases though because i put them on along with every other mod i have at the same time. but the crafstmanship was decent and i dont have any leaks yet. it's been a little over 2 years

I think that especially if you weld a flexpipe in, they aren't bad at all. Only reason I get so pissy about them is the bad experience I had with them on a couple different cars.

Up here, with all the deicer, I think they would be a good choice for a summer car.
-Garrett

TheRacingVolvo · 6-29-04, 12:45

[fizzle] pacesetter!! those things leak like a sive(sp?)

i put the Bosal brand ceramic coated headers on my girlfriends car. (93 MX-6 KL)

before that i had installed the custom magnaflow exhaust, and K&N intake system, so other than sound and the top end power, there wasn't too much that impressed me.

**JeremyL** · 6-29-04, 14:10

the $600+ most quality headers for our cars cost im sure could be much better spent elsewhere, like some Bf Goodrich KD's

**Victheslic** · 6-29-04, 14:38

I've heard good things about HS, and plan to get them myself.

TheRacingVolvo · 6-29-04, 15:06

Quote:

Originally Posted by JeremyL

the $600+ most quality headers for our cars cost im sure could be much better spent elsewhere, like some Bf Goodrich KD's

yeah, they are kind of expensive, but i picked them up for about $460.00.(cost)

**barkster** · 6-30-04, 0:51

Quote:

Originally Posted by skiiingman

There can be significant power gains in controlling the loss of energy in the exhaust. You want the exhaust to be as hot and high energy as possible, so that your careful tuning causes the very lowest pressure pulse possible near the exhaust valve when it opens. If you let the gasses cool down, they are less effective in this regard.

I think that especially if you weld a flexpipe in, they aren't bad at all.

Garrett, I believe you completely on that. I was looking at the RRE flex pipes, if the header didn't come with one.

Quote:

Originally Posted by TheRacingVolvo

[fizzle] pacesetter!! those things leak like a sive(sp?)

i put the Bosal brand ceramic coated headers on my girlfriends car. (93 MX-6 KL)

Ok... I've heard much bad about pacesetters... if I can sheppard this thread back to the technicals, though...

Bosal = Mild steel with cermic coating. How does that compare to stainless and/or heat paint or powder coating? Maybe if I got Bosals and added a coat of heat paint before I installed them? Would that prevent the rapid rust formation that mild steel is susceptible to? Hotshot is mild steel (coating?) and I believe Pacesetters are stainless.

Oh yeh... and I'm moving to DC where it is HOT in the summer and more than cold enough for snow and corrosive road salts in the winter.

Thanks again, all.
Glenn

**Victheslic** · 6-30-04, 7:39

They use road salt here in Texas... On those 1/4 winters where it ices pretty bad.

**NHxj4x4** · 6-30-04, 8:59

Quote:

Originally Posted by Victheslic

They use road salt here in Texas... On those 1/4 winters where it ices pretty bad.

That's funny, come northeast buddy, we turn cars to dust with the amount of salt they pour on the road, it's silly!

**skiingman** · 6-30-04, 9:02

Quote:

Originally Posted by NHxj4x4

That's funny, come northeast buddy, we turn cars to dust with the amount of salt they pour on the road, it's silly!

Hehe yeah, up here they don't just dump NaCl on, they use KCl on real cold days, which is even more corrosive.

And, since its a byproduct of the industry and super cheap, they are now using MgCl, which will eat through rubber balljoint boots in months and all sorts of nasty things.
-Garrett

TheRacingVolvo · 7-1-04, 12:51

yeah, that potasium **** is definitly corosive.

i think that you should get a set of bosal headers. you could always shoot them with a high temp paint if needed, but the ceramic holds up pretty well. how long do you plan to live in that environment? i think that there wouldn't be any harm in painting them as long as you used a high temp paint and maybe few coats. thinking about this more i woul probably go ahead and do this so that you can try to prevent raock chips from starting the steel wrought procces.

no harm in that, right.

**barkster** · 7-1-04, 14:09

Quote:

Originally Posted by TheRacingVolvo

i think that you should get a set of bosal headers. you could always shoot them with a high temp paint if needed, but the ceramic holds up pretty well. how long do you plan to live in that environment? i think that there wouldn't be any harm in painting them as long as you used a high temp paint and maybe few coats. thinking about this more i woul probably go ahead and do this so that you can try to prevent raock chips from starting the steel wrought procces.

no harm in that, right.

I guess not.... and thanks for the reply... (I grew up in Marietta, by the way.... tell me the "big chicken" at 41 and Roswell is still there, please!)

So... if the ceramic and an extra layer of high temp paint are enough to counter the downfall of mild steel... then maybe it looks like Bosal or Hotshots are the choice for me. I here a lot that Hotshots fit very well, but don't offer too much in boost. How about the Bosals? Any fit/leak problems with those (like I always hear about Pacesetters?).

Putting it all together, now... does anyone have any mechanical or material warnings, experience or advice AGAINST the following: (and sound doesn't matter)
Bosal headers, an aftermarket (RRE?) flex pipe (I don't thing the Bosal comes with one), Random Tech high-flow cat, and "yet to be determined" catback.

Is flanged or welded better?

Answer that and I think I'll be ready to go shopping.

Glenn