KL Engine Headers FAQ

[Gro Harlem]

I don't know about you guys, but I am personally sick of all the header threads being posted on MX-3.com and also on here. I wish people would search, although the information about all of the headers for the Probe are spread across LOTS of threads on here.

I decided to do a few searches myself & compile the information I could find. I thought that the price, primary, y-pipe & outlet sizes, construction, fitment, sound & power gains are what most people are concerned with when it comes to headers so I compiled all the info I could find & listed it below.


K-Series Engine Header FAQ:

Here is a list of the headers available and what I've found (from researching ProbeTalk):

Brospeed / Bosal Headers:
Price: $350-450
Description: Ceramic-coated mild steel construction. Short equal-length primaries. Equal-legnth Y-pipe that secures with a balljoint
Primary Size: 1.625" (outer)
Outlet Size: 2.5" at collector, then tapers down to 2.125" (inner) 2.25" (outer) to fit the stock cat size (for probes at least)
Power Gains: Dyno results varied from 4-11whp over stock. Torque gains were from 5-8 ft lbs. Gains were particularly good from 3500 and up. Peak power gains surpass hotshots but don't quite reach pacesetters results.
Sound: Described as raspy by some ProbeTalkers. Sometimes Rattles from 2000-2500rpm's due to balljoint design (lack of flexpipe)
Fitment Issues: fitment is good according to people on probetalk with these headers


Pacesetter:
Price: $180-240
Description: Mild Steel Construction. long unequal-lengthprimaries. Unequal-legnth Y-pipe that secures with a balljoint
Primary Size: 1.5" (outer)
Outlet Size:
Power Gains: I've seen varying results. As much as 17whp to as low as 7whp gains. Torque gains were anywhere from 5-10 ft lbs.
Sound: Very Raspy.
Fitment Issues: Pacesetter updated their design in 2004 for better fitment. Apparently there is still problems with the Y pipe bolting up to the primaries. The O2 sensor bung placement issues have been fixed however.

Hotshot:
Price: $410-500
Description: Coated Stainless Steel Construction. Short equal-length primaries. Equal-legnth Y-pipe that contains a flex-pipe.
Primary Size: 1.625" (1 5/8")
Outlet Size: 2.5"
Power Gains: Varying results from 4whp to as high as 13 whp. Torque gains seen have been consistent from 5 to 8 ft lbs.
Sound: Keeps the tuned sound of the K-series engine. Best choice for those who want the best sound
Fitment Issues: Fitment is great!

SSAutochrome:
Price: $175-200 on ebay
Same as pacesetter generation 1 headers but made with stainless steel which is less likely to rust. ALso the primaries are 1.625" (1 5/8") instead of 1.5". The fitment is the same however. O2 sensor bung placement issues & difficulty with the primary-y-pipe flange were voiced by people who bought these headers.

OBX (also called Stone Racing):
Price: $250-300 on ebay
Same as Hotshot headers. Stainless steel construction, decent welds, flexpipe, nearly identical to the hotshots. Fitment is also good.

Also note that SSautochrome sells these exact headers and uses their brandname on them as well. The ones I received from ebay came in a ssautochrome box with stickers. SSautochrome posted messages on ProbeTalk about redesigning their header design and I guess they decided to just knock off the hotshots


I have the OBX headers on my car and they fit fine with no issues. O2 sensors clear everything. My EGR bung is plugged so I don't know if that fits properly, but other than that, I'm satisfied. I've had them installed for 9+ months and they show no signs of rust, however the typical purple/orange/blue/green discoloration has occured on the primaries. I live in an area where it snows & they salt the roads and I'm particularly surprised that they show zero signs of corrosion so far.

[Gro Harlem]

Continued......




Other things related to headers:

Balljoint VS Flexpipes:
Since the engine moves independently from the body when it accelerates & decelerates it generates movement. Since the exhaust is attached to the body there needs to be a little bit of give in the exhaust system. This is typically done by a flexpipe on most cars. However with the Bosal, Pacesetter & SSautochrome headers, a Balljoint. These are cheaper to manufacture but are more prone to leaking. You may have to re-tighten the bolts securing the balljoint periodically to keep it from leaking. Flexpipes with a flange are virtually leak-proof assuming you use a new gasket & tighten the bolts to spec.

Primary length:
Longer primaries always spell higher RPM power for any engine, but they can also reduce the gains and possibly remove power from the lower-midrange RPM's. Shorter primaries are good for low-midrange power especially, but can't produce outrageous high-RPM gains. This is why the pacesetter headers make the most power of all of the 3 designs.

Construction:
The type of alloy that is used plays a role in how long the headers will last before they corrode. Mild-steel is very prone to corrosion and WILL rust almost immediately upon exposure to the air. Pacesetter coats their headers with black paint but the paint quickly burns off and rust begins within 2 weeks. Stainless steel is less likely to rust but will begin to in the winter months when salt is thrown on the roads. Unless you live in colder climates, there shoudlnt' be any concern buying mild-steel headers or exhaust peices. Also, exhaust manifolds can heat up to well over 500 degrees. Polished Stainless steel has a tendency to discolor in these kinds of temperatures and will appear a swirly purplish blue color relatively soon after installation.

And also for the record....YES these FIT the K8 AS WELL!! The fact is, the K8's stock exhaust manifolds are stampled "KL01". My KL-ZE even had "KL-01" stamped on them. The only fitment issue on the MX-3 is the catalytic converter. It needs to be pushed back about 2" since the Probe / MX-6 has a completely different chassis w/longer exhaust sytem.

[Gro Harlem]

Also, if you see anything you think is incorrect, or think I should add something PLEASE POST IT!!

And please don't turn this into "pacesetters are better" or "hotshots are better" pissing contest. I don't care what headers are better, they all have their own merits & I just want to post the facts so the n00bs can stop posting threads all the time.

[HondaSpanker]

very nice writeup

[baaka]

Hey Gro Harlem. Pacesetters are better. Haha. No I'm just dicking around.

Great post. Very informative. Only thing I can think of is adding in what the effects of unequal vs equal length primaries has. Other than that, I couldn't ask for more.

[1997]

Hotshots aren't stainless steel as you say, they are coated mild steel.

[quicksilv3r]

You have it wrong about the SSAutochromes. They are short primary design just like OBX/Hotshots.

[Gro Harlem]

You have it wrong about the SSAutochromes. They are short primary design just like OBX/Hotshots.

there are two SSautochrome header designs, the old style is the pacesetter style and most people refer to these as "ssautochrome headers". and as we all know, pacesetter has long primaries, as do these headers.

The new style is the OBX/ssautochrome hotshot knockoffs which have the short primaries.

I have actually owned both ssautochrome styles. I have pictures if you wanna see the differnces between the two styles.

[Gro Harlem]

Great post. Very informative. Only thing I can think of is adding in what the effects of unequal vs equal length primaries has. Other than that, I couldn't ask for more.

Bingo! I actually started writing a paragraph about it, but figured i'd hold back and not make a huge jackazz of myself. I'm not very sure what effects it has other than unequal = raspy sound.

If a member here could explain that would be awesome

ANother thing would be the size of the primaries, secondaries, outlet, etc and how bigger = bad in the case of our engine. I read something like 1.75" is too big for the KL and 1 5/8 is pushing it. I don't know much about the physics of header design so I won't even attempt to explain all that.

[Gro Harlem]

Hotshots aren't stainless steel as you say, they are coated mild steel.

Thanks! i wasn't actually sure. I did a couple searches trying to find out what they are made of but coudln't get a straight answer. I already edited the post.

Also, are the brospeed/bosals SS? I just assumed that the hotshots & bosals were SS since no one here ever bitched about them rusting like the pacesetters do. Maybe it just has to do with the coating process on the hotshots (they are done properly i would think).

I also didn't even bother mentioning the pacesetter "armor coat" headers. I don't really know of anyone who bought these and I don't see why anyone would. They are nearly the cost of hotshots just for a stupid coating. I know a buddy of mine with a 92 Protege LX (1.8dohc) and he bought the blue-coated "armor" pacesetter headers. The crap burnt off just like their black paint!

[reids97pgt]

what about interprep headers they are 1.75 in

[quicksilv3r]

there are two SSautochrome header designs, the old style is the pacesetter style and most people refer to these as "ssautochrome headers". and as we all know, pacesetter has long primaries, as do these headers.

The new style is the OBX/ssautochrome hotshot knockoffs which have the short primaries.

I have actually owned both ssautochrome styles. I have pictures if you wanna see the differnces between the two styles.

Yes I know all of this. But why would you post info about the old design if what's available TODAY is the hotshot/obx knock-offs? Or why not post information about BOTH designs and not just the old ones? FYI, the NEW design isn't all that new anyway, it's been out since the middle of last year sometime...

[turbo_KL]

And the Hotshot sytle is good for turbo use.

[ouch1011]

A couple things I've noticed:

1) Pacesetters use long equal length primaries and unequal length secondaries. And the outlet size is 2.5" OD, same as their catback system.

2) The effects of the primary length that you have written are backwards. Longer primaries help with midrange power, while shorter primaries are best for high RPM peak HP gains. This is why it is suggested to use really REALLY long headers on most large displacement V8s, because most of them a wheezing by 5500 rpm, so a short primary length would not do much for them. The pacesetters make the most power of the bunch (supposedly) because they are long enough to suppliment our engine's fairly low peak horsepower RPM. Hotshots are too short to work as well, but if you were building a high HP N/A KL where you were looking to make your peak power in the 8000 rpm range, the Hotshots would be the way to go.

Otherwise, a very good FAQ writeup. I wasn't aware Pacesetter changed their design... any pics of the new generation?

[Omaha95PGT]

Well, I don't know much about the current crop of Brospeeds, but the one I have (circa 2000) is mild steel and ceramic coated.