I recieved my Monster Motor Works 4-2-1 Race Header after the November Group Buy last Monday after a short backorder. The headers were backordered due to the need to update their entire stock to reflect a change due to (as far as I knew) a fitment issue.

Prior to the change the MMW 4-2-1 header was a 2-piece (correct me if I'm wrong)design incorperating an s-pipe. Several threads about the header's circulated these forums where it was stated that the header did not throw CEL's and was free from rasp. I cannot personally comment on the pre-update header but I had listened to some sound clips where there was no noticable rasp.

UPDATE (MMW, or anyone for that matter, please chime in if you feel any of these details are incorrect):

CHANGES: Details being verified.The updated header is now a 3-PIECE design! I will post pictures that I took prior to installation later today. The header comes with the first two pieces press fitted together with small plate brackets holding them together. They are very tightly fit, so you will not be able to just remove the brackets and pull it apart without a fight. The spipe has a flared end that hooks up to a half-dome soft metal gasket on the end of the header and gives you a good degree of motion between header/spipe for any fitment to any exhaust. Top notch mfg.

PICS: Sorry about the fingerprints, the stock polish job was very good:











RASP: There is a VERY noticable rasp throughout all rpm's with the 3-piece version. It only goes away when youre not on the gas. Almost embarrassingly loud. My setup prior to install was Creative Compact's full stainless steel exhaust, Borla Muffler and a Hi-Flo Cat. I also have a K&N cold air intake and Camcon.

I took the car to a local muffler shop today, they installed a resonator and the great exhaust note of the CC setup was back. No rasp left at all, great tone. I'll get a sound clip for you all soon.

CEL: There was no CEL for an estimated 650 miles of highway driving. I was running the Camcon the entire time as well. MMW has addressed the issue of the header throwing CEL just like all other aftermarket headers with the development of an antifouler type fix. You can find the details in the following thread, https://www.scionlife.com/forums/viewtopic.php?t=93911. There seems to be a loose remark from WR that those whove bought the MMW header will recieve the antifouler when theyre happy with it's performance:

PERFORMANCE: As has been already addressed several times, power is very noticable on the butt dyno and the bottom end 0-3k rpm didnt drop out with this header. Still pulls great from any rpm and flys above 4k. Should be great once retuned.

 

your lucky.. i recieved mine.. and had problems installing it.. i received the three peice aswell.. but thre was no way to install it since it was up against the center frame member.... id like to see the pics of your install to see how your header fits... question.. did you recieved instructions with yours..?

i left them a message saturday.. i know there were closed up until yesterday... and i have sent them 2 emails so far.. still wating to hear from them... i don;t have my receipt with me, and that is the only place with a telephone number... their website only has email addresses......

 

Had the same problem when I first tried to get it in. All you need to do is remove your radiator fan housing, then it goes in like cake. Real easy:

1. Look down on left/right of radiator there will be a bolt on each side of the fan hoising. Take them out.

2. Follow the fan wires, unclip the connectors and move the wire out of the way.

3. Start pulling up on the housing (Black plastic only). It will be stiff but work it side to side.

4. There are small tabs at the bottom of the housing that may get caught up on the radiator hose on right and a at another point on the left. Just push one side down a bit and carefully pull the tab past the radiator hose on the right without pulling it off. Then the left side should come out easily.

5. Set it aside and look down into your engine bay. You now have an extra 2.5-3" to work with. Turn the header assembly 180 degrees counter clockwise from the monting position and snake it down through the open space.

6. It helps to have a friend up under the car to guide the spipe end of the header around the oil pan and subframe as you turn the header top mate up to the engine. It should go without too much sweat with the extra room to work with.

It was impossible from what I saw to get it in without taking the fan housing out.

Hope this helps, let me know if you have any other problems.

 

thanks.. i got that far... after about 30 minutes of trying to snake it in... ..but once i got it almost on the exhaust studs the lower end of the header hit the center frame member.. and it would not go pass that.....

thanks though.... im looking forward to seeing your pics..

 

I want to see pics of the redesign. sounds interesting.

 

I was underneath before we took the fans out, so I know the dynamics of what was goin on before taking them out. I was holding the top end of the header when we put it in, my buddy was underneath the car. I just remember it being cake after the fans came out.

I'll get to posting the pics now.

 

Theres all the pictures I tooke before the install. Let me know if you have any questions.

 

there's no redesign...it was always a 3 piece. alot of us here just said 2 piece because we were excluding the s pipe since we were having problems with just the main piece.

 

Yeah after revisiting some posts (MMW site is down tonight), youre right, it seems it was always a 3 piece. I don't remember seeing the side brackets holding the pieces together which made me think those were additions.

If you check closely on the blurry pictures here, youll see the brackets: https://www.scionlife.com/forums/vie...916&highlight=

So if I may ask, can any of you help pick out the differences between the pre/post updated headers so I can revise the first post?

The first thing I notice is there is an extra weld on the downpipe of the far left cylinder of the updated header.

Also it may be the angle but the O2 sensor bung is at a different orientation.

Did the spipe on the original header have the flared end?

 

Also forgot to mention, I was CEL free for about 650 miles. I had the camcon running the entire time with the tune leftover from when I was headerless.

I'll add it to the above info.

 

everything looks pretty much the same to me. when i installed mine i was too lazy to take off the fan housing so i just took it apart and installed the main piece first, lifted the car, and then installed the bottom half plus the spipe. ive talked to Leo and they pretty much have only changed the fitting issues. its all hand made, so there's going to be mistakes at times, but i think everything is straightened out with that...some ppl were CEL free for about 600 miles also, some people got it in just 3 to 5 days. i myself got it after a week....i then bought an anti-fouler, and it went away, and has been away for about 1000 miles already...MMW is currently testing out their new anti-fouler which is supposed to stop CEL's caused by headers for good on the tC, so once thats out, i'll get that just in case my CEL ever pops up again. hows the header by the way? lovin it huh?

 

Not true. I have a two-piece: Here's the proof:

http://img.photobucket.com/albums/v7...-_-/Sidex2.jpg
http://img.photobucket.com/albums/v7...ader-spipe.jpg

Also, there is a thread regarding the change (after the groupbuy as mentioned by the original poster)

 

ok, sorry, it was a 2 piece when it first was introduced and advertised to the public and only a couple were sold like that...u happen to be one of the people that got the 2 piece....i think there were like only 3 made like like that...but after that, it was a 3 piece, and nothing changed.

 

Yes, you are right about that....and it was two, not three :D

 

well.. i think the fitment issue is still a problem... i have one that does not fit..... i even took the 2 halves apart and tried to mount the lower half after mounting the upper... and there is no way to get it together since the end hits the center frame member... and it seems NOW! that there will be closed until JAN2 .. their original message said DEC 26.. i know .. i know.. im sure they will take care of the problem.. but it is frustrating......

on the positive side.... the headers are a work of art... they do look so good.. it is hard to do them justice in pictures.. im sure Fushyuguruwould agree...... too bad that you can not keep them from turning that golden color...

 

yeah, after meeting a friend/rep of theirs and seeing how they've been taking care of issues as of late, I'm sure they're going to be willing to send you a pair of new ones. I know that their earlier 3-pieces were off just a bit......

 

thanks for the encouragement... im sure they will do the right thing..

 

My CEL just went off this morning, after driving around town for 20 miles or so it hasnt come back on.

Anyone else have it go on/off?

 

uh....probably not. Your gas cap might have been loose O_O

 

This is a very nice looking header. Sorry I do not have anything more important to add to the disscussion, just wanted to say it looks sweet