Cat no the STD header?

[blade34609]

Hi,

I was reading my repair manual on my 88 STD hatch and it said they have a cataylic convertor on the header, all DX and SI's had them in the exhuast piping. I looked in my car and sure enough there was a cat there.
Isnt this a big reason the DX has 92 and the STD only has 70hp.
I was thinking of buying a pacesetter header off of ebay because they are a good price. I heard a lot of people talking about how shitty they really are. But i also heard people say they have had them on their car for a long time with no problem.
Im definetly gonna get a 4-2-1 header but will i notice any difference with my MPFI swap and intake?
Thanks

[marked001]

I had a paceshitter header on my zc...no complaints about it besides the paint all coming off....but yeah, that setup will work if you get a new exhaust...

[91civicDXdude]

the difference between DX and STD has been covered many times.

only the 88 STD had the HF style manifold.

STD has a restrictor plate between the throttle body and intake. It has a different ECU, and possibly a different cam.

[alexdog69]

Yep.. the STD has a cat on the manifold... I put a Focuz ceramic coated header ($99+S&H on eBay) .. wrapped in charcoal Thermotec header wrap ($30 off jegs.com?)... and a OBX 2.25" midpipe (~$75 on eBay from SSautochrome.. also available at www.ssautochrome.com... it even bolts onto the stock rear section)...also an eBay "high flow cat" (aka a stainless steel glasspack with the Honda stock cat flanges welded on it) to bolt the header to the midpipe... (and a new OEM NGK/NTK O2 sensor for good measure).... and WOW..what a difference!!! The motor is no longer this disgusting anemic pig below 3000rpm... I HIGHLY recommend this combo...

If you get an aftermarket exhaust/midpipe.. You will need something to bolt in between it and the header .. where the cat normally goes on the non-STD cars...

My experience with Pacesetter/Monza products... on both Honda and air-cooled VW.... is that.. well.. they are pretty crappy... everyone in ACVW knows the "Monza exhaust" .. it is the notoriously cheap crapyp exhaust with 4 chrome tips... Some of their headers actually have tons of weld flash and/or the actual weld seams on the INSIDE of the collector.... Boo!!!... For $99 on eBay you can get a chinese made DC sports knock off thats been ceramic coated... a much better choice IMHO.. mine has held up quite well even with the wrap over it... snow... and repeated 70mile round trip daily driving with extended bouts of >100mph cruising ... the coating is still intact... no flaking.. no rust...

I also put a complete 2.25" rear section on it..and well..I feel like it lost quite a bit of low end torque for just a small top end gain... we modded it and now it's running a home made "silencer" to reduce the diameter back to stock after the muffler.. this seems to work the best... low end torque with high rpm gain..After having someone fab the 2.25" rear... we cut off the muffler with a recip... and had 3 different mufflers (stock OEM Honda, cheap "Turbo" muffler [a cross between chambered and straight-thru, really], and a Hooker AeroChamber straight-thru)... also a resonated tip.. a 2ID"x27L" cherry bomb glass pack...and a stock midpipe resonator .... we tried various combinations of these parts.. and running the 2.25" turbo muffler with the stock midpipe resonator connected to the outlet (this was just an experiment...looks like shit) seemed to be the happiest... had some high RPM boost and tons of low end torque.... and the sound is great.. nice and quiet and stock like with a little bass added in... I think if it had MPFI and a Si cam.. it might be a different story, however... as it may like a slightly larger diameter...

But with that all said.. getting rid of the stock rear section didn't really make a big difference, it just made the car louder and gave a very tiny boost in power... The mid pipe / header / fake cat.. is where all the real improvement came from ...

As for STD vs other models... with a MPFI conversion (Si manifold w/ TB, injectors & sensors & mounting bracket + Si ECU + Si distributor), a Si or JDM SOHC ZC cam, header/cat/exhaust and a cold air intake (not short ram).. you should be making a bit more power than a stock Si despite the ~100cc's displacement difference... the valve and port sizes in the head are the same... However, that 4 speed tranny will definately be a huge bottleneck...

as MistaBone (somewhat well known Honda hacker) had a similar setup on his DX 1.5L D15 5G hatch.... (stock MPFI but D16Y8 intake manifold IIRC)... he used a 4G Civic/2G CRX Si cam... Stillen header.. 2.25 crush bent exhaust... AEM CAI.. and he was dynoing approx 120hp to his wheels / ~135hp flywheel....

Anyways...

STD's are ok... Get an eBay ceramic header + "high flow" cat + OBX midpipe .. and you will be loving life... you can worry about a MPFI conversion/cam/5 speed or or full swap later on... that stock header with the cat is choking that poor motor...

I have a STD... it's fun... it needs the ZC motor/5spd LSD trans to finish it off.. The handling is utterly ridiculous... Tein SS.. F&R strut braces.. F&R subframe braces... F&R 22mm Sway bars w/ custom fabbed mounts in front... Yokohama AVS 195/50R15 on 2000 Si wheels...

It makes a lot more power than stock with the mods... But the 4 speed transmission SUCKS... and the DPFI is garbage... Those are the major restrictions that really make the STD slooooooow... Either do a swap, or get MPFI, a Si or ZC trans and a cam.. and you will be very happy with the power output...

[blade34609]

Ok thanks for the info.
So your saying I cant just buy a ebay 4-2-1 hearder and just take off the STD header and put my Ebay one in its place?
Will I have to buy the other 2 things?
THanks

[alexdog69]

If I recall correctly ... the stock system uses a manifold --> catalytic converter --> downpipe ...

the downpipe ends where the aftermarket header would end...

and the stock midpipe extends farther forward than a model with the standard style cat... as it has a section of straight pipe where the catalytic converter would normally be ...

so you need a cat (ebay glasspack "high flow" style or a "test pipe" or real one), if you want to use an aftermarket exhaust ... BUT the header should go right onto the stock exhaust system and basically delete your cat ...

Here are some pics from when we did the upgrades on my car...


As you can see the header is a direct replacement for the stock manifold/cat/downpipe assembly... in the pic the stock downpipe off the cat is rotated 180 degrees relative to the header... so they look like they are different.. but they are not..take note of the donut gaskets on the two down pipes... that will give you an idea of how everything goes together.... You will probably want to buy a new donut gasket and the little ring that goes behind it... I used Fel-Pro p/n 60517 and 60669...



And in this pic you can see the stainless 2.25" OBX mid-pipe and "high flow cat" (stainless glasspack with Honda cat flanges on it).... next to the stock midpipe.... as you can see, there is a section of straight piping on the stock pipe where the catalytic converter would normally be on the other models....

so, you should be ok with just the header

[alexdog69]

Also, if you are planning on doing this .. I would recommend that you use a Mr.Gasket CopperSeal header gasket... to prevent any leaks (it is especially good insurance if you are going with a low cost header)... you can get it from www.optauto.com amongst other places ...

also, it is a good idea to use the die grinder to remove any weld flash or other crap on the inside of the inlet ports of the header (if needed).. so that it has a nice match to the gasket and thus the head's exhaust ports....