Hey guys, i want a DP and i was just wondering which one was the best one.. like price and quality.. i know they all have the same purpose and i read threads about ss vs mild steel.. what's the diff.. would buying a mild steel be alright? thanks in advance..

 

I just ordered the M2 downpipe a week ago because it seemed like it would be the easiest one to install and I'm still waiting for it. Apparently they're out of stock now even though they weren't when I called to ordered it... From everything I've read, a downpipe is pretty much a downpipe as far as performance except some are easier to install fit a little better than others. With the M2 downpipe, you should not have to remove the turbo manifold studs like many of the other downpipes. As far as mild steel vs. stainless steel, I really don't know. Stainless steel would last longer but also expands more than mild steel when heated. I would think that having different materials for your exhaust piping wouldn't be too great, but lots of people are running the M2 pipes and other stainless steel downpipes with no problems. Any more information would also be appreciated. If there are any downpipes better than M2, please let me know so I can cancel my order and get it sooner...

 

HKS DP was a lot easier to install, than most the other DPs out there. It's mild steel though. I think, although I'm not sure, that mild steel wont look so great after awhile, as opposed to stainless steal. Other than that I dont know the diff...so if that is all, u'll never see the DP when driving around, so who cares. I'd reccomend the HKS cause it's also a lot cheaper.
Hope that helps.

 

HKS, easy install, great price,

 

I have apettit SS DP that was a horrible pain in the *** to put on. If I had to do it over again I would go with the HKS DP for ease of installation and then get it coated with that jet hot stuff to keep it from getting rust and stuff like that. You can get the HKS DP for about $200. I'm not sure how much the jet hot is, but I don't think its very much. All of that together would probably cost less then my pettit SS DP and will likely save you much cursing while putting it on.

 

It's $60 for jethot to coat hks dp with 2000 coating. and $22 for shipping it back.

 

I'm thinking of buying the HKS since its easiest to install, but I heard rumors that they are extremely hard to get nowdays. Is this true? DOes Jason at the store have them in stock? Thanks. BTW, if the studs come off, and you have to remove the turbos, how hard is that to do? IS it removed from above the car, or below?

 

The stainless steel downpipes are more resistant to corrosion compared to mild.

As for fit, all down pipes have the potential to have problems fitting, but the effort is more than worth it in breathability and a cooler engine bay.

The one I have (Bonez) was built to last. The steel of the mandrel bent pipe was the thickest I have ever seen on a exhaust system, and the mounts were bloody thick! No grinding to fit it at all.

One note: Make sure the oxygen sensor (normally on the precat) wire is placed AWAY from the engine and the turbos. It has a nasty tendency to melt to the turbo plumbing down there

 

I have the RX7.com stainless. Excellent quality and fit perfectly.

 

To me the benefit of not needing to remove the studs is that even if they come out when you undo the nuts, you can just put the studs, stick the gasket on, then slip the DP on. Where as for the petit I have you have to take the studs out tape the gasket to the turbo, then have one friend hold the DP up for you from the bottom of the car while you try to line all the holes up without being able to see the holes and then get the studs through those holes while trying to menuver around your friend thats holding the DP up. Just my experience.

 

So does anyone know whether the HKS ones are hard to come by nowadays or not? Does Jason carry them still?

 

Funny....i never had a problem installing my Pettit ss dp. O well, it works, and i'm happy. Cj

 

Is it true the HKS mild steel downpipes make a pinging or metallic type noise different than the pre-cat or original setup.

Has the HKS downpipe always looked different than the pettit, like the rx7 store pics, or is this a new design.

 

The flange is designed like the stock ones, so it slips right on. it also has that thing near the cat end that bolts to the body for extra support.

 

Hmmmm...well...why don't yo ask Jason?