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-   -   Muffler Shops won't install Hi Flows (https://www.f150online.com/forums/exhaust-intake-systems/455586-muffler-shops-wont-install-hi-flows.html)

tjmud2 Aug 24, 2011 06:42 PM

Muffler Shops won't install Hi Flows
 
Sorry if this has been asked before but I did several searches and came up empty handed. I bought the 94106 Magnaflow Hi Flow Converters for my 99 F150 SC 4x4 with the 4.6L V8. I went to two shops and they both said that they wouldn't install because I didn't buy the Magnaflows from them, and there was not enough profit in just he labor to complete.

Can someone please outline the install process of the Hi Flows because both shops put the truck up on the lift and said that they couldn't do it as they would not be able to weld all the way around and make a perfect seal with no leaks.

I had thought make a cut right in front of the first cat, and one right after the last cat. Put the new hi flow cat in the middle, and piece in pipe between the cat and O2s. Both shops acted like they needed to take the exhaust all the way off from the manifold flange, remove all 02s, and drop it down to make complete welds.

What am I to expect for installation, can they not complete without removing everything? My truck is very rusted and I am sure that things will start breaking when trying to remove flanges and 02s.

Do they need to remove the 02's and weld in new bungs?

Any advice would be appreciated on the install process.

azmidget91 Aug 24, 2011 06:51 PM


Originally Posted by tjmud2 (Post 4664008)
Sorry if this has been asked before but I did several searches and came up empty handed. I bought the 94106 Magnaflow Hi Flow Converters for my 99 F150 SC 4x4 with the 4.6L V8. I went to two shops and they both said that they wouldn't install because I didn't buy the Magnaflows from them, and there was not enough profit in just he labor to complete.

Can someone please outline the install process of the Hi Flows because both shops put the truck up on the lift and said that they couldn't do it as they would not be able to weld all the way around and make a perfect seal with no leaks.

I had thought make a cut right in front of the first cat, and one right after the last cat. Put the new hi flow cat in the middle, and piece in pipe between the cat and O2s. Both shops acted like they needed to take the exhaust all the way off from the manifold flange, remove all 02s, and drop it down to make complete welds.

What am I to expect for installation, can they not complete without removing everything? My truck is very rusted and I am sure that things will start breaking when trying to remove flanges and 02s.

Do they need to remove the 02's and weld in new bungs?

Any advice would be appreciated on the install process.

they are right, cut right before first cat, tack weld in the cat and extra pipe, weld in o2 bung, drop exhaust from manifolds to fully weld and then bolt back up

keep looking you will find a shop that will do it

88racing Aug 24, 2011 06:59 PM


Originally Posted by azmidget91 (Post 4664010)
they are right, cut right before first cat, tack weld in the cat and extra pipe, weld in o2 bung, drop exhaust from manifolds to fully weld and then bolt back up

keep looking you will find a shop that will do it

x2!....

avfrog Aug 24, 2011 09:56 PM

x3! Those 2 shops are too damn lazy to do it apparently.

tjmud2 Aug 24, 2011 10:34 PM


Originally Posted by azmidget91 (Post 4664010)
they are right, cut right before first cat, tack weld in the cat and extra pipe, weld in o2 bung, drop exhaust from manifolds to fully weld and then bolt back up

keep looking you will find a shop that will do it

Is there anyway to do it without dropping the exhaust from the flanges? My exhaust is completely rusted and if we need to remove at the flanges and remove the O2 sensors to drop then I'm afraid I'm out of luck as the rust will cause everything to break. Nice Midwest Salt in the Winter.

I was hoping to cutout and weld up the hi flows in place.

avfrog Aug 24, 2011 11:46 PM

If he was a good welder he could do it without dropping it down. a simple mirror, and you can see to check the weld on top for holes. I am a welder, and it can be done, if your good.

88racing Aug 24, 2011 11:49 PM


Originally Posted by tjmud2 (Post 4664165)
Is there anyway to do it without dropping the exhaust from the flanges? My exhaust is completely rusted and if we need to remove at the flanges and remove the O2 sensors to drop then I'm afraid I'm out of luck as the rust will cause everything to break. Nice Midwest Salt in the Winter.

I was hoping to cutout and weld up the hi flows in place.

I'd keep shopping around....

97XL Aug 25, 2011 12:32 AM

I had the same issue, had to go to 3 shops before I found one that would install mine. The excuses I got were, "It's illegal and we can get fined." They welded mine in place with no leaks and that was 3 yrs ago.

azmidget91 Aug 25, 2011 11:01 AM

i guess its possible to weld it in place but if it were me id drop the exhaust

4.6 Punisher Aug 25, 2011 12:53 PM


Originally Posted by avfrog (Post 4664227)
If he was a good welder he could do it without dropping it down. a simple mirror, and you can see to check the weld on top for holes. I am a welder, and it can be done, if your good.

Agreed, that's how my exhaust guy does it. Probably not as good as dropping the whole system.

avfrog Aug 25, 2011 09:05 PM

^ Looks are irrelevant on the top side of the joint. No leaks is what is important!

Drizzle Aug 26, 2011 04:33 PM

to the original poster...I feel your pain man. I bought a set of those same cats a couple years ago and basically got the same responses from local muffler shops. Some said they couldn't do it at all because it was illegal, and the ones that said they would do it, took a look at it, and said they would have to take the exhaust manifolds loose and drop the whole thing to weld it correctly. They said they couldn't physically fit the welder wand in between the cat and the heat shield to weld the top side...hence their reasoning to drop the whole exhaust system first. I basically walked away and returned the maggie cats I bought when guys started saying "yeah I can do it...but I'm not sure you want to pay me to do it".

It just wasn't worth it to me so I said forget it.

DarrenWS6 Aug 27, 2011 12:59 PM

x2 on dropping form the downpipes. My old trucks exhaust leaked at the rear converter deletes. Drove me nuts, probably robbed a couple MPGs.

tjmud2 Aug 30, 2011 01:38 PM

Went to another shop today, he seemed more confident and talked a good game. In short, $120.00 per side ($240.00) total, but he keeps the cats, thats the only way he will do the work. He scraps them out and keeps the money, so he said if I must have the Cats, then I need to go somewhere else. So does $240.00 sound reasonable?

Installation would be unmount at the manifold flange, and cut right before the rear O2 sensor. remove all 4 cats, weld in the 2 new ones, mount back up to the flange, and weld in before th O2 sensor. This will require him to only remove 2 sensors instead of 4.

Opinions? Does he sound reputable? He was recommended by 3 shops, and does custom exhaust work on hot rods.

88racing Aug 30, 2011 01:48 PM

It's sounds like he knows he's good and he's going to charge you for it.....depending on where you take them for salvage....I think he's hi......keeping the cats to boot.....


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