Magnaflow Catted H-pipe

[NinJa_FLiP]

I did a quick search on the forums for this and came up empty handed. Anyone hear anything about the Magnaflow catted h-pipe like the one here: http://cgi.ebay.com/ebaymotors/1984...r_Truck_Parts_Accessories&hash=item3c98ed8e47
I'm mainly concerned with fitment. I'm going to keep it emissions legal for here in NV, and it only requires 2 three-way cats. Thanks fellas..

 

[drakesdad]

I did a quick search on the forums for this and came up empty handed. Anyone hear anything about the Magnaflow catted h-pipe like the one here: http://cgi.ebay.com/ebaymotors/1984...r_Truck_Parts_Accessories&hash=item3c98ed8e47
I'm mainly concerned with fitment. I'm going to keep it emissions legal for here in NV, and it only requires 2 three-way cats. Thanks fellas..

It's cheaper than the BBK catted in Summit catalogue I was perusing last night.....

 

[NinJa_FLiP]

yea that's the reason i was checkin it out.. not tons cheaper but enough to look it over.. lol

 

[nmcgrawj]

I'd trust magnaflow over bbk.

 

[drakesdad]

I'd trust magnaflow over bbk.

I have Magnaflow exhaust on the GTO, no complaints on quality or sound..

 

[NinJa_FLiP]

yea i just hope its 2.5" diameter piping.. lol..

 

[fordtech28]

I have that H pipe on my cobra its fits pretty good I didnt have issues putting it on

 

[NinJa_FLiP]

perfect.. thats what i wanted to hear.. thanks man

 

[WhiteCobra95]

I just purchased this H-pipe about two weeks ago. The plan is to install it next week.

A couple of key points: 1) It is 2.5" and 2) it's stainless! I have laid it on top of my factory H-pipe and the flanges all appear to be in the stock locations. Overall, it looks like a very high qaulity part and it's a steal at the current Ebay prices. Just make sure that the place you order it from still has them in stock, Magnaflow has discontinued this H-pipe and only offers X-pipes with converters now. I'm adding in extra O2 sensor bungs for wide bands and deburring the flanges, then it's ready to install. I just have to change out my T5's speedo gear for a future gear upgrade before I put the exhaust back in.

Before I nabbed this gem, I ordered the BBK equivalent. It's junk. Frist, it's alumized pipe at a higher price. The one I received from summit already had a ton of surface rust everywhere: rust at all of the joints where the pipe bender scratched off the aluminzed coating and rusty flanges - out of the box, brand new. Second, it's not a solid assembly - they cut the down pipes from the manifold to the cats for easier packaging, and give you a giant band clamp to seal them up. I have been an engine calibrator for over 15 years, and I know what air leaks do to cats; You do not want any additional and unnecessary junctions upstream of your converters. Air leaks = failing NOx emissions at a minimum, or a melted cat.

 

[NinJa_FLiP]

Thanks for the info. I bought mine one tuesday for super cheap! I'll be getting it next week. Let me know how the install goes. Thanks again

 

[WhiteCobra95]

Did you guys have any issues with the installation?

I have found three problems so far:

1) the stock H-pipe hanger bracket doesn’t fit right on it. Their bracket is too wide and the rubber hanger donut won’t fit properly. I had to make a ½” spacer block, the width of the stock bracket, and that has fixed it.

2) The span between the two header flanges is too close by about a 1/2 “ to ¾.. I was hoping that the flanges would draw them into place, but I just started the car and it has a huge exhaust leak on the passenger side bank.

3) the angle of the down pipe on the passenger side makes it really hard to tighten one of the header nuts. The stud end up at an angel with the pipe where you can’t get a socket over it. I had to use a wrench.

I'm probably going to have to pull it back out and see if I can stretch it a bit with my floor jack to resolve the flange issue. If that doesn't work, I'll have to trow the O/R piple back on and take ti to shope. Stock replacement bolt-on my #$%.

I am so sick of aftermarket exhaust hassles! ARG!

 

[Venom351R]

Ive never used magnaflow mid pipes but Ive had two of their exhaust systems before. I currently have a Bassani Catted X pipe and it fits sweet

 

[blksn955.o]

I have the catted BBK X that I picked up for $100 slightly used and I sold my O/R H for $50 so it only cost me $50 out of pocket. Mine was all one solid assembly and the only rust is at/on the welds.

That said I would say Magnaflow is probably the better quality though.

 

[NinJa_FLiP]

My Magnaflow Catted H-pipe fit like a glove. Nothing had to be modified at all.

 

[WhiteCobra95]

Thanks for the feedback.

I wonder if my BBK shorties are the culprit. I never ran the stock H-pipe with the headers, I only used their O/R H-pipe until now. I know these parts are all supposed to interchangeable, but who knows with aftermarket tolerances.

I’m going to try to drop it tomorrow after work and see what’s going on. It’s really hard to tell since you can’t get a good view of anything when it’ on the car.

Another side note: I only ran it for about 5 minutes at idle. I was pleasantly surprised to hear that the cats really haven’t muffled the ehxaust too much compared to the O/R pipe. At idle, I would give it a subjective 20% drop in exhaust loudness. I’ll have to see how it is at WOT. This H-pipe also fits very tight to the transmission and body which I really like. My BBK O/R pipe hung a bit low for my taste.

 

[desertcox05]

i've had to tweek my h pipe before,
just pull it back out and set 1 side on the ground, with your foot holding it on the ground just push or pull the down pipe to spread or close the gap between the down pipes.
I measured the old one I took out and "made" the replacement match up using a tape measure.
you don't need much pressure to move those pipes together a 1/2 inch.

 

[WhiteCobra95]

I finally had a chance to work on my car again tonight. I measured the width of all H-pipes involved and here’s what I found (this is the distance between both header flanges, pipe OD to pipe OD):

Stock H-pipe: 24 and 3/4”

BBK O/R H-pipe: 24 5/8”

Magnaflow: just shy of 24”

To gain the extra distance, I used my floor jack and a couple pieces of wood to add some spread. On the first attempt, I went to far and ended up at 25.25”, so I used a ratchet strap at the flanges to bring it back. The ratchet strap took about 5 conservative tried to get it right.

In addition to this, I also elongated the flange holes for the header bolts to give more adjustment on the bank 1 header.

Anyway, I just got the H-pipe bolted back in and I’m hoping for the best. I didn’t have to muscle the pipes this time, so hopefully that’s a good sign. I didn’t have time to get the O2’s back in place along with the cat-back, so I will try to finish tomorrow morning and do a quick leak check.

Thanks for all of the replies, I really appreciate the help. Cross your fingers for me!

I still wonder if this is just a symptom of having the BBK shorties, which may not be using an exact stock flange location. What headers are you guys running along with your Magnaflow H?

 

[WhiteCobra95]

That did the trick! No leaks this time around.

I have to retract my previous statement about the exhaust volume; at idle, the noise level is a little bit softer than the off-road pipe. Driving and under load it’s a whole lot quieter. My 1,900 to 2,000 rpm drone is gone, but this is way too quiet with stock mufflers – almost as quiet as the whole stock exhaust. A cat-back is going to be mandatory now.