Probably a dumb question, but are these still available new somewhere? I wonder about buying a used SSI since the actual pipes are not stainless and in theory could still rust and leak exhaust into your heater system. Maybe there's a way to test them for leaks.

They are not available new any longer.

keep looking for a set that has SS pipes and heat exchanger boxes....they are out there. I sold a set a couple of years ago...
good used ones may go anywhere from $500 to $800+

I spent a whole lot of time earlier this year trying to track down a new set of SS H/E. No joy. I was willing to compromise and get a new set of carbon steel H/Es from Germany, and could only get one side. I ended up getting a nice pair of SS H/Es from a member of the Forum last month. I'd think that would be your best bet in the short term.

Paul

Wow. You can buy all sorts of mufflers and headers for the 914, but not SS heat exchangers? That's too bad.
What about new steel he's? If those exist maybe they could be Jet coated right out of the box for better longevity.

now you are talking even more "unobtainium"

just be patient and find a nice used set of all SSs.

If you can find someone with new ones (NOS, but they are out there) they cost somewhere around $1200 or so. You could get a tangerine header for that kind of money, and get WAY more out of it.

Go used. They are just as good the second time around as they are the first.

Zach

I am pretty sure the SSI's I have are all stainless. They are definitely not new and there isn't a speck of rust on them. I got the whole setup for $500 of the classifieds here.

Maybe I'm missing something...but I just got a set of 1.7 stainless H/E off ebay for less than $200 shipped.

Troy

The actual SSI exchangers were all stainless, so used should be just as good as new. At least on 911s, people started calling all aftermarket stainless exchangers SSI, but not all were.

As with all these parts, they're getting older and harder to find, so the price sometimes reflects that. If you're patient and keep looking, there are fair deals out there.

2.0 SSIs are much pricier. If they are in mint condition they are literally worth a mint

What is SSI? Is that a brand? How can you tell SSI from non-SSI?

I thought the 1.7 HE's were preferred for the 2.0's...

i am talking out my ass - but my GUESS is that 2.0 SSHE's flow only VERY slightly better than SSHE's of the 1.7/1.8 style. Maybe so slight as to not result in any noticeable hp or torque improvement ???

In 30+ years I've never heard that. No basis for it. A complete 2.0 exhaust, from 1973 or 1974, from head to exhaust tip (including the muffler hanger) and especially with SSI brand heat exchangers would be the best stock system for any 914/4 from 1970 through 1976 models. High performance systems are another thing, and there just consult with Chris Foley.

SSI is a company. I believe they still make stuff for the 911 in stainless.
If stainless 914: they are SSI.
If NOT stainless 914: they are NOT SSI.

Paul

I know where there is an NOS set of 73-74 2.0L SSIs...the guy won't part with them for any amount of money... According to the manufacturer, they will never be manufactured again.

Got my SSI's new in '76. ALL stainless. Never, ever a problem & they shine up beautifully. Too bad SSI decided to discontinue production, because this is a lifetime product (maybe that's why?). Never cheap, but worth every penny.

Still plenty to be found here & eBay. Go for it!
Pat

There are 2 different flavors of SSI HE though. IIRC one has mild steel flanged and the other has stainless flanges.

Take a magnet to it.

Wherever it sticks is non-stainless...