What is better, a S.S. or Cast Iron downpipe? I talked to someone and they said that all the S.S. downpipes start to crack after some time. He said that it didn't matter which S.S. downpipe it was, that he has seen them all. He said that it would be better to get the HKS Cast Iron one. What is your guys opinions on this?

 

My opinion?

Get the CHEAPEST one, and then get it either ceramic coated or www.jet-hot.com coated.

Even if you get the el-cheapo pipe fencing DP, the coating will still protect it from rust and heat.

 

I'm not sure which is better but you're gonna want your DP to handle this









time and time again

 

How long are you talking about? Yes the SS is more likely to crack but sometimes that could take a very long time. I have friends that have had SS manifolds and downpipes on for yrs. with no cracks.These are different cars too....not just 7's.It kinda depends on the application,whether it needs flexpipe and doesn't have it or any # of other reasons.IMO the SS if priced within reason is the one to go with.If it wasn't I don't know why almost every motorsports area in the world uses SS other than mild steel or iron.It has to have a few good qualities.....just my $.02

 

yes the HKS uses a steel casting at the flange -(looks like same casting as the stock pre cat) but the pipe is either SS or Mild Steel (HKS makes both types) MS won't last very long - Rotary Exhaust heat will burn through in a few years at the most. the M2 SS unit uses a Plsma cut SS flanges about 1/2" thick w/ stress relieved (slotted) mounting holes I doubt it will ever crack w/ normal street use -M2 uses it on their Road Race Car. The M2 unit is also full 3" dia tube and the HKS is only 2.75" tube

 

Thanks for your input. I guess I'll just go for the S.S. one and see how long it lasts. Thanks again.