I did some searching, but didn't come up with much. I'm beginning modding my FD, and I have the apexi intake right now, next I am doing the downpipe (should have done this first I suppose), then if it comes out I am doing the AEM EMS with a walbro fuel pump in about 2 months followed by a Koyo rad. I am unsure on which downpipe to do. The HKS mildsteel, or pititt SS or M2 ss. what are the benefits of SS over MS? thanks guys!

 

The only difference is going to be corrosion and oxidation resistence. The ss will have less propencity to rust. That's it. Aside from the money.

 

if I powder coated the MS wouldn't that help to offset some of the corrosion?

 

might save some weight with ss also..but not much.

 

Yeah, plus you'd have the benefit of the ceramic coating itself. But now, you're almost at the price of the ss downpipe. Honestly, the mild steel downpipe would probably outlive the car. It's up to you.

 

Ceramic (Jet-Hot) not powdercoat. Just wanted to make that clear.

 

just picked up my HKS downpipe from the store. it fit great and was fast to do. the HKS downpipe comes jet coated so no need to get the m2 or pettit. dont spend the extra dough on the m2 or pettit. use the money for the fuel you will need. i went through a tank really fast after the downpipe install. no, its not the downpipe that was making me lose gas, just the fact that i can now hear the turbos wine and i love showing off.
kris

 

HKS pipes don't come Jet Hot coated...

I went with the HKS. I wasn't really concerned with how long it will last, since it will probably last the life of the car, and I've never heard of one rusting out. The only thing that I really disliked about the pipe is that kink in the cast section where the o2 sensor plugs in.

 

HKS it is!

 

The odd look of that kink is the reason I ended up getting the Pettit instead.

 

well then, jason at the store lied to me. he said that the hks downpipe was jet coated, which is why i went it. when i started it up the downpipe smoked, then again it could have been the wd40 i put on the bolts before hand. either way, jason at the store has lied to me twice, unless the fact that it is jet coated can be backed up.
kris

 

The one that Jason sells is Jet-Hot coated. I'm not sure when it's done (before or after he originally gets it) but it is ceramic coated.

 

The HKS downpipe is coated... but not Jet Hot coated. It comes w/ some kind of coating from the factory (that silver stuff that was all over your hands after you installed it) but it's not "Jet Hot" coated. I doubt the ones RX7Store is selling are Jet Hot coated... not for $200.

 

That silver crap that gets all over the place is not the coating. That stuff has something to do with the cutting and welding. But I have had this conversation with Jason before, and he assured me the downpipe was ceramic coated. I doubt he would make that big of a mistake.

 

well atleast he was giving me the run around and lying. its bad enough that i was charged 4 dollars more than what i was quoted. the money was not what i was pissed about, just the fact that he rounded up to an even 1200.00. honestly,has anyone else had this problem?
kris

 

the sliver kink in the HKS DP is to compensate for right hand drive cars (japan) i would get an american one like m2 or pettit because they do not have the dent which means less restrictive air flow.

 

SS saves about 3 pounds on the downpipe over MS. SS is about 8 lbs, MS is about 11.

SS has better thermal properties than MS, so your engine bay will be cooler with an SS downpipe. Thermal-coated MS is even better, and thermal-coated SS is even better still.

-Max

 

Anyone ever thermal wrap their DP's. What effect would this have on performance and reliability? Any ill-effects?

Ant

 

A buddy of mine suggested it. He doesn't own an FD, actually a Talon pushin' around 300 HP with thermal wrapped DP I think. Anyway, he knows his stuff and thought my car might benefit, what do you fellers think?

 

hi thought i would throw my 2 cents in. i own a prototype and development shop in san diego i work with all types of metals and stainless happens to be 1 i work with everyday. theres some things you should know about stainless well it applies to all metals. there are several grades of stainless out there theres cheap stainless the kind that will let a magnet kinda stick to it then theres really hard stainless the kind that breaks your carbide mill bits in a second. the reason for variety is application for example most stainless knives are made with surgical grade ss i believe it is 308 thats really clean ss so do alittle homework on the grade you need wall thickness find out if its rolled or extruded and there you have it oh yeah i buy my stainless tubes and or pipes and or bars from a place called taco in northern cali. it comes polished so you wont look like a skid mark from polishing. oh and 1 more thing the aftermarket stainless exuast systems ive seen like the n1 are very nice and it might seem expensive but polishing welding and buying stainless isnt cheap either good luck...

 

The ones I sell at the store are not Jethot coated. Suprfast I appologize if you misunderstood that. I dont remember the conversation but typically I tell a customer it comes coated with a substance similar to ceramic that helps prevent rust. Jet hot coating is only done by Jethot. The $4 dollar difference that you were charged was extra shipping. I dont ever round up. Alot of time the price comes out even because my prices usually dont have any $cents added.

The HKS DP is a nice downpipe for the $199. Its going to out live your car anyway so dont worry about it being mild steel.

If you have any questions about your order send me an email or give me a call

Thanks
Jason
www.rx7store.net

 

I have the ATR SS DP and MP. I got a deal buying them together for 380 bucks. I believe they are 304 stainless. I have no idea how high of a grade of stainless that is. It does have a nice finish and has not rusted in the past few months I have had them installed. The fit was perfect and the price of course was great. As for saving money on the mild steel. If you buy the DP and MP together I think you save a bunch.

 

I thermal wrapped mine with this cloth wrapping stuff I bought from Summit Racing. It seems to have worked pretty well, although I never measured before & after temps or anyting like that. I also put the wrap on when I first installed the DP, so I don't have any before/after comments from that either.

I pretty sure there's a negligible, if any, change in performance from the thermal wrapping. I just did it to keep engine bay temps down. That *should* increase reliability. The company that makes the thermal wrapping says it will increase power by making the exhaust flow better, since hot gas flows better than cold gas, or something like that. I REALLY doubt that would make any noticible difference.

I think thermal wrapping it or ceramic coating it is a very good idea to keep temps down. I think the wrapping was $30, and I've heard Jethot coating is around $70 + shipping.

 

Someone said they used 3 things of the wrap, and they could touch their dp after a hard run, and it was only warm to the touch. Pretty cool.