redlightrich

iTrader: (1)

Hi All, I have a pair of 95 7s, and one is a real low mile car. It actually still has the original pre cat. My other one already has an aftermarket downpipe in it. I bought both equipped as they are, so I don't know what brand is in my one car,

My question is there a big difference between the ebay 130 dollar down pipes, and some that I have seen for 330 from the more famous suppliers?

I am not worried about it discoloring, as I would imagine the intense heat will discolor most all of them.

I am starting my reliability mods on my low mile, and precat is first on the list ( along with a racing beat cat back system!) I don't plan any future exhaust mods beside what I just mentioned.

I don't mind paying more for the downpipe if it offers some advantage, but most I have seen are stainless, and have the O2 sensor bung and so on. The less expensive one even had gaskets!

Any input would be appreciated

Thank you

Rich

misterstyx69

iTrader: (142)

Fast reply:
Id' consider proven Higher quality that won't break due to heat soak.Light material,faster heat dissipation.
Even if you get a cheap heavy pipe that stuff can absorb heat,you'd end up wrapping it and in the long run spend just as much for a good quality pipe.

Sgtblue

iTrader: (16)

IF IT WERE MY CAR......
I would get a high quality mild steel downpipe made for the LHD models. Look for thick flanges at both ends. Also the better ones IMO will have a bracket toward the downstream end that allows it to bolt to the side of the transmission for stability. The cheaper ones don't. Bonez is a good one...but there are others. I'd then have some type of quality heat-coating/header-coating applied to reduce under-hood temps. "Jet-hot" is common.
And due to the higher heat of the rotary exhaust, I would only buy OEM gaskets. Use lots of high-temp anti-seize on all fasteners and exhaust studs during installation.

redlightrich

iTrader: (1)

Thank for the input all. I have decided to buy a good quality one, and I am going to wrap it for good measure. Keeping the heat in the pipe is a good idea.
Also, I did just order and receive a factory gasket. Yes it is more expensive, but it is so much more substantial than the cheap aftermarket.
I will use the ultra copper on the studs on install.

Thanks again for the ideas and input.

Rich

Sgtblue

iTrader: (16)

IMO, heat-coating is preferred. But if you intend to use header wrap, I recommend either getting a stainless DP or spraying the mild steel DP with DEI's sealant/paint before wrapping. And then seal the wrap with the same stuff afterward.
One can is plenty. ---> HT Silicone Coating 010301 | Purchase DEI, CryO2, Ny-Trex, Boom Mat & SPA Turbo Products | Design Engineering, Inc. - Thermal Performance Products

RotaryResurrection

iTrader: (8)

The problem with the ebay downpipes is that they do not physically fit the car well at all. They almost always

1) have the oxygen sensor bung in the most inappropriate place, pointed into the rear turbo Y pipe.

2) the angle of the front flange is wrong, such that the pipe runs into the rear turbo compressor housing, and you have to bang on the pipe to clear it

3) the angle of the pipe is even further off at the bottom where the midpipe meets, and you may find that you have to cut, bend 2-4 inches, and re-weld the downpipe so that the bottom flange is where it should be.

Really, a used, known fitting downpipe is the way to go for cost and quality. It's a pipe, there's not much to go wrong with it as long as it was originally made in the correct shape.