wow ive finally finished installing my headers. i must say that it was a lot of work (9 hrs for me), but it is worth it. thanks to everyone on this site who have helped my and given me advice. my flowtech LTs sound awesome on my borla, and the TA is noticably faster. i do have a problem though. the drivers side of the header/y-pipe connection bangs the floor and i can feel it on my feet at higher rpms. what should i do to fix this?

 

Poly motor mounts, weld in an old valve spring where it's banging, or loosen the clamps on the y-pipe and re-tighten them with a 2x4 inbetween the y-pipe and the floor. The poly's are probably the "right" way to do it. The other two...well...form your own opinion on those.

 

what exactly are poly motor mounts, and are they difficult to install? i thought that i would have to have a muffler shop use a torch and bend the pipes so they dont bang, o shouldnt i do that

 

I guess a muffler shop could take a torch to the y-pipe and bend it. But then you give up a little ground clearance. I've never installed the motor mounts, so I don't know how difficult they would be. But, they're on sale at T.R. http://www.thunderracing.com/catalog...&vid=3&pcid=92 I'm sure someone else will chime in soon...

 

I thought i was going to be having a problem with that when i got my FLP's, if i'm right they use to have that problem, not sure if i never got it cuz they redesigned their system a lil bit or if maybe it was a problem with 98-99's or what, but i don't get any banging on the floorboard. There use to be a site, i think TheFBodyShop.com, not up anymore but i think i read it there that just getting some type of hosing and putting that around the ypipe where it hits would take care of the problem, for the time being i would say go ahead and do that. Thats what i was gonna do until i found out i didn't have any problems.

What header gaskets did u end up goin with?

Anybody know what happened to that site? TheFbodyshop.com?

 

i used the supplied paper gaskets from my flowtechs, but they seem to have sealed fine

 

I'd try the valve spring method or you can try some large band clamps (big enough to go around the exaust pipe and hose) and some hose for a cheap fix. Either way you should get it fixed because when it bangs the knock sensors can detect it and cost you some power.

 

I'd try what SSpdDmon suggested about loosing the clamps on the y-pipe and re-tighten them with a 2x4 inbetween the y-pipe and the floor..I think you'll find installing motor mount to be a pain in the ***. JMO

Al

 

motor mounts solved all the problems for me. the motor barely moves now when reved.

the install for me took 10 hours alone. most of that was trying to get the mounts out from between the block and the front crossmember. and then contorting to get the bolts back in.

this was with manifolds on...with headers i don't even think it's possible to get to without removing the headers. you need alot of room to get them out.

that is why i suggest to anyone i talk to that they should swap the mounts with the manifolds out during the header install. it would make it a 1 hr job probably.

 

the problem is that the header is very close to the floor on the driver side, and the ring where the y-pipe attaches to the header does touch the floor , so when i accelerate it bangs. so even if i tried to bend the y-pipe using a 2x4, would that work considering that the header is so close. i dont know if i could bend it enough. also that wouldnt cause any leaks would it?

 

how bout a 2lb persuader (hammer) on the floorboards.

my flowtechs come pretty close to the frame/floor boards but not touching. and the motor mounts prevent any banging.

 

yeah its the ring bolts to the y-pipe that touches. if i would hammer the floor board, would it actually make the inside where the driver sits rise up higher, and how much would i want to raise it? 1 inch? i wonder why your flowtechs didnt touch and mine did?

 

hard to say why yours is closer. i know mine IS close but with the poly motor mounts the collectors barely move 1/4" when reved up.

if you put in mounts i don't think you'd need much clearance, but with the stock mounts...you could very well need all of that 1".

like i said hard to say.

and yeah it seems strange that headers fit cars differently. it's a luck of the draw thing i guess

 

ok i managed to pound some of the floor up and now it really doesnt vibrate noticably. it might still slightly, but not much. i have like 1/2 inch clearance, so i may try to get more later. thanks for all the advice this is the first time ive ever done this, and it turned out well.