HOW TO: Replace GReddy Header Gasket - Honda Prelude Forum

92 SI Ludester · 05-06-2003, 06:00 PM

On the GReddy 4-2-1 header, where the 4-2 pieces meet usually tends to have a weak gasket that goes bad. I made my own gasket and replaced the GReddy one with this.

Parts:
Mr. Gasket - Ultra Seal gasket material

Tools:
Dremal
10mm socket
12mm socket
14mm socket
Vice grips

For this i had to take off my front bumper to get up my driveway. Its not nessary but make it a lot easier not worring about scratching up the bumper or anything.

Next take out the radiator. There are 6 screws on the radiator support that come out with a 10mm. After that use a vice grip and unclamp the hoses from the radiator (upper hose) and the hose by the thermostat hosing (lower hose reaches around motor to the upper left corner). After those 2 car taken off take the vice grips and unplug the tranny cooler lines located infront of the radiator. Next take the 2 plugs out, one on each side. After that pull and the radiator should come out.

After that you will have to take off the power steering pump. To do this you will have to take off the 2 bolts on the top (outlet hose). Next take off 3 bolts that hold in on 12mm. After you get them off losen the blet and pull the pump off.

Now all that is out of the way take off your header. There are 9 (12mm) bolts that hold the header to the block and 3 (14mm) bolts that hold the header to the downpipe. After you get the top part of the header off your car should look like this

Now look at the damage done. This is what my gasket looked like.

Take the bad gasket and place it ontop of the Mr. Gasket material and trace.

I was only able to trace 1/2 and then I filled the gasket around and traced the other 1/2 that way. After you are done tracing it will look like this

Using the dremal cut out the new gasket. After you are done hold it up to the old one to make sure it is the perfect size.

I put exhaust gasket sealer on the two header pieces to make sure the gasket sat right and had no leaks. You dont have to.

Now that you have your new gasket, put everything back on. Start with the header, then power steering and last radiator. After you are done start it up and see if the new gasket worked. I had no problems. Remember to fill the radiator up before you start because you will spill a lot of fluid when taking the hoses off. Enjoy your new gasket

dublued · 05-06-2003, 07:10 PM

is the gasket sheet available at any parts store?

92 SI Ludester · 05-06-2003, 07:14 PM

i went to a speed shop near my house but i am sure any auto parts store may carry it

Brady92/4WS · 05-06-2003, 07:48 PM

i think you did a lot of unneccassary work just toget your header off.

92 SI Ludester · 05-06-2003, 08:02 PM

like what? the middle bolt needed an open box to get it off and with the radiator there i couldnt get it in...maybe i could of just taken the fans off but it took about 10 mins to get the radiator off...pump needed to be taken off because it blocked one of the bolts and even a open box couldnt take it off...correct me if im wrong? i am lazy and i tried to do as little work as possible...took the bumper off so i could be closer to the compressor and use an air gun instead off a ratchet

4bidden · 05-06-2003, 08:29 PM

heheh, I sure as hell never did that much work to take off a header.

You dork.

go pre · 05-06-2003, 09:33 PM

is there some minimum writeup length for getting the free po.com membership? you really didn't need to add all those unnecessary steps to this. the 2-1 piece can be removed by simply unbolting it from the cat, header bracket, and then from the 4-2 piece using a long extension from under the car. replace the gasket and bolt it back in. the 4-2 piece doesn't even need to come out.

92 SI Ludester · 05-06-2003, 10:50 PM

as soon as i get my really cheap car lift to use in my driveway, i will work from the top of the exhaust system down rather than under the car...i had to take my bumper off to get up my driveway, think how much fun it would of been to put that car on a lift...well may not be the minium way to do it, but for 1 1/2 hours work, you wont hear me complain

LudedudeSi · 05-07-2003, 07:14 PM

is this the gasket that gives the greddy header a buzzy boost kinda sound? because my makes an awful noise.

92 SI Ludester · 05-07-2003, 07:48 PM

yeah it sounds really bad...if i find out how i will try to get a video clip of my car at the track with the leak...it sounds like your muffler is under your hood not behinde your car...i have extra material if anyone needs it or i can make them another gasket...the longest part of this whole thing was making the gasket...took me about 45 mins to cut it out and make it the right size...the rest was 30 mins off, 30 mins on

Satan_SRV · 05-08-2003, 07:18 AM

That free membership thing was just a promo, it's not offered anymore that I know of...

Dude thank you so much I am going to have to track down some of this mr. gasket stuff tonight for my greddy header.

Now I don't actually have the gasket...could you do me a huge favor? Trace another one on paper and scan it and e-mail it to me??

jaybro · 05-08-2003, 10:54 AM

like everyone else said...definately dont need to remove the radiator and PS pump buddy...just use extensions...lol

Edit: I personally wonder whether or not the excess material from that mr gasket stuff that gets squeezed away from the gasket when re-installed, if when it gets burned up in exhaust flow will clog your cat. I wouldnt be surprised

92 SI Ludester · 05-08-2003, 12:42 PM

what free membership? i already paid...anyway, only thing about scanning a pic in is that it wont be the right size...not sure how to get a pic into real size...maybe i can put measuring tape around it and make a box that is 5x5 so you can use that?

i have no cat

...but i smoothed down the sides and inner circle that there wasnt any extra material hanging over

Satan_SRV · 05-08-2003, 01:41 PM

no I meant like scan the sheet of paper that you trace the gasket onto, then it will be actual size...at worst I just use the header and a bigger piece...you don't need to worry about it if it's a hassle.

92 SI Ludester · 05-08-2003, 05:05 PM

i will give it a shot i dont mind...i just dont want it to be the wrong size and it doesnt fit or something...i will hook my scanner up tonight and i will pm you when i am done

4bidden · 09-01-2003, 02:16 AM

Great info for us leaky Greddy people!!!!!!

TrustJDM · 09-02-2003, 02:05 PM

Greddy sells that gasket piece for $18-20. I had to buy another too, but after 2 yrs. it still works fine. If you're lazy and got $20 to spare, just get it through Greddy or an authorized Greddy/Trust dealer.

4bidden · 09-02-2003, 02:54 PM

$20 for that gasket!!?!?!?!?!?!?!?!?

Jeeeezeeeeeeee!!!!!!!! Reckon they're making any off that? Holy cow!

93si4ws · 09-02-2003, 04:32 PM

someone needs to put together a buy on that gasket material...

4bidden · 09-02-2003, 04:45 PM

Yea, I just want a large sheet of that Mr. Gasket stuff.