libertyforall1776

iTrader: (2)

So my Vert. Camaro SS is out of the shop (no lift access so I didn't want to attempt it) after installing American Racing Headers' 1 3/4 to 1/7/8 Stepped Headers & Catted Y, Noweeds Diverter plugs/wires/new OEM MLS gaskets, new OEM motor mounts, and 1LE rear LCA bushings -- more muscular sound and feel, and no SES codes thus far! As the picture below implies, the fit is tight between the 1 7/8ths section of the headers and the OEM K-Member on the driver side. The result is the headers touch and make noise at some points with certain movements and RPMs due to this, not sure if this is a convertible-specific issue -- maybe I should have stuck with 1 3/4... The shop did a little grinding of the K-Member corner, but it will have to go back for some more adjustment. I am also going to phone ARH to see what they have to say...

Any advice from anyone else with similar issues? All help appreciated!

The Noweeds diverter is top notch -- very nice operation, fully automatic, wicked sound.

libertyforall1776

iTrader: (2)

72 views and no inputs?!

bene

iTrader: (16)

The 1 7/8" tubes looks beefy! I would suggest if you can grind or pound with BFH the K member to where it'll clear the headers completely.

TheSilverOne

iTrader: (22)

rubber mounts are going to move. Go poly or solid

alexus6798

iTrader: (24)

Yeah, mine makes a little noise if I stab the throttle from a stand still. I haven't really worried about it because I plan on putting in prothane motor mounts soon.

libertyforall1776

iTrader: (2)

So everyone with 1 7/8 or stepped headers has issues with the K Member then? Damn, just put the new OEM rubber ones in there assuming that would help. Didn't go w/poly since I was trying to minimize NVH, but this was unexpected. Grrr. I am really surprised there are not more comments about this issue -- at least others will be more aware now for their installs...

alexus6798

iTrader: (24)

Mine only makes a noise when you take off aggressively, so I don't worry about it.

libertyforall1776

iTrader: (2)

^ Yea, but it's annoying as hell... Must fix.

Mumbles

iTrader: (5)

Here is your fix.

I realize you just had your originals replaced with new, but you need to bite the bullet and upgrade to rectify this problem.

z-maro

iTrader: (18)

No, but I don't have ARH's. Mine are Edelbrock's and have no fitment issues with stock MM's and 3.5" collectors.

libertyforall1776

iTrader: (2)

Update: Sent pictures of the rubbing spot and spoke with Mike and then Nick (Owner) at ARH, and they are going to correct the issue and replacing the driver side header which touches the K-Member intermittently on engine start, left and right hand turns and at various drive RPMs. Hopefully this fixes it.

Moral of the story, if you have fitment or quality issues with a product, you have to call the company, else how will they know about the issue, and how would they fix it if they are not given the opportunity?!

99'CajunFirehawk157

iTrader: (57)

My TSP 1 7/8" headers never hit the k member, but my Y pipe hits at times under the drivers side seat like they all do...but I will conquer that soon.

99Bluz28

iTrader: (35)

IMO, regardless I would have installed poly motor mounts, they really don't increase NVH much at all.

libertyforall1776

iTrader: (2)

So after much back and forth with Midwest Muscle Cars, they still did not resolve and identify the header hitting issues I had -- not happy with that experience at all, and they even charged a premium!

Kudos to Nick at ARH who continued to help resolve the problem and arranged to have the car clearanced and checked today at Speed Inc., and no more banging! Apparently the first shop did not take enough material off the driver side K-Member! With this done I am happy again! It pays to work with a shop that does more installs on LSx f-bodies!

So in the end -- the poly motor mounts were NOT required! But NEW motor mounts I do recommend, and installed (OEM rubber in my case)…

Now I just need to address my low hanging diverter a bit -- but Speed helped with that too by adjusting the exhaust.

38DD2436

No problem hitting with mine. Poly motor and trans mounts.

dr_whigham

iTrader: (49)

All of this would have been avoided by going to the poly motor mounts to begin with.

The OEM rubber you replaced them with is still going to rot and sag eventually, more so with the additional heat in the engine bay.

99Bluz28

iTrader: (35)

IMO, poly motor mounts are a no-brainer. The benefits far outweigh any minuscule NVH you might perceive.

alexus6798

iTrader: (24)

My car actually stop making the noise once I had my subframe connectors and other rear suspension parts installed. Not sure if it had anything to do with the headers at all..

libertyforall1776

iTrader: (2)

Nah, it would have been avoided if ARH included some install notes as to what should be done with install of their hardware! The ARH owner himself proclaims that poly motor mounts are NOT required! It would also been avoided if I had the install at a more F-Body LS1 experienced exhaust install shop.

If so, I will pass that bridge when I get to it… In retrospect I would get my next set of headers coated… Poly can melt and then sag, and I have read accounts of the same, here for instance: No benefit there. Read the post by CurtP 01-08-2009, 06:38 PM
http://mallcrawlin.com/forum/showthr...nts-for-ZJ-WJ&

Never had them, but how do you measure the benefits? Poly cold flows too, is that a benefit?

Poly is cheap, I guess that's a benefit… I would be more interested in a higher durometer rubber.

AmarilloWS6

iTrader: (3)

Poly motor mounts not only lessen the chance of this happening again once the originals crack and sag again in 10,000 miles, but it makes everything crisp. There's really no increase in vibration I didn't notice but I did notice the motor was A LOT more responsive now that the motor is in it's place and not rocking side to side. I loved them enough that I did them in my c5 too hope you get your issues solved though. Ever thought about going with a tubular k-member? You'd save weight and the header would be far away from the k-member.