HELP: The SSI's I bought don't fit my car!

05-26-2003, 11:13 PM

About a month ago I bought a set of SSI's for my Euro 1984 911 Carrera 3,2 from Pelican Parts.

I received them in a large cardboard box and they looked fine with the thick flanges and collars as necessary on a 3,2 model. I was happy.

UNFORTUNATELY yesterday as my mechanic wanted to install them he found out that they aren't the correct size for a 3,2. The inner tube diameter in the tubes that enter the cylinder heads is only 1,37 inches (35mm) and the diameter should have been 1,5 inches (38mm) which is stock for a 3,2.

Now we're confused. What 911 are the heat echangers, I received, for? My mechanic says the tube diameter of 35mm is for an older model, probably a 2,4, but why would they have thick flanges and collars then?

I have tried contacting Wayne and SSI, but haven't been successful.

Anyone who knows about this?

speeder · 05-27-2003, 01:36 AM

I'm sure that you will get a definitive answer on this, but I believe that SSI only makes "SC" model headers, (the ones that you got), they are the ones for a 3.2 even though not optimum size. This is the reason why HP gains on 3.2 are not as dramatic as on the 3.0 or 2.7. They will still flow much better than stock exhaust.

RoninLB · 05-27-2003, 06:07 AM

Quote:

Originally posted by speeder
, but I believe that SSI only makes "SC" model headers, (the ones that you got), they are the ones for a 3.2 even though not optimum size.

I just got the thick flange SC model because my stock 2.7 heads had room for the exhaust protector at the top of the flange.. so now I have a O2 bung.. the routine for my 2.7 is a different SSI model..........Ron

Formerly Steve Wilkinson · 05-27-2003, 06:13 AM

Hey Mikkel, I think that's the case. The i.d. of the SSI's is sized for the 3.0 engine. I have them on my 3.4 SC, and they work fine. Just slap 'em on and walk away.

We had a fantastic drive through Denmark last week--got as far as Skagen, after touring lots of Fyn, then back down to Arhus and the ferry across to Overby and on across to Helsingor and back down to C'hagen. You've got to try some of those marigold-route roads on Fyn and Jutland--they're fabulous. I've never driven on more interesting or fun backroads anywhere in the world. Get that Carrera of yours off Zeeland!

I posted a long message about our meeting, but it didn't get many responses, other than some Swede who said I should have come to Sweden instead...

Keep in touch,
Stephan

07:32 AM

Quote:

Originally posted by speeder
I'm sure that you will get a definitive answer on this, but I believe that SSI only makes "SC" model headers, (the ones that you got), they are the ones for a 3.2 even though not optimum size. This is the reason why HP gains on 3.2 are not as dramatic as on the 3.0 or 2.7. They will still flow much better than stock exhaust.

Yeah I remember that, but I thought differently after reading Brad Roberts comment in one of my old threads: I got this e-mail on backdating to SSI

I mean having collars that extend into the cylinder head that aren't the same size is rather silly. Worsens exhaust gas flow I would say.

05-27-2003, 10:50 AM

Ronin

You mean you have thick flange SSI's on a 2,7?

05-27-2003, 01:22 PM

A question to you who have SSI's. How do you avoid exhaust gas escaping past the tubes when the tubes are smaller than the cylinder head ports?

CamB · CamB's Garage

I have them on my 3.4 SC, and they work fine. Just slap 'em on and walk away.

And I have them on my 3.2 short stroke (245hp at hubs), so its not holding that back either.

Formerly Steve Wilkinson · 05-27-2003, 04:07 PM

Mikkel, I'm not sure I understand your question about exhaust gas escaping if the SSIs are of smaller i.d. than the cylinder-head exhaust-outlet ports. Perhaps I'm missing something, but the problem--if there is one--is simply one of the SSIs being slightly more restrictive in handling the outflow, which is a problem in an ideal world but seems to be less of a problem in the real world. With the SSI flanges bolted to the cylinder-head outlet ports with an exhaust gasket in place, why would gases escape? Certainly they don't seem to be doing so in my car.

By the way, when we were in Copenhagen last Saturday, there was a Ferrari 456 with Finnish plates parked in the show-off spot in front of the L'Angleterre. Mika?

Stephan

marcesq · marcesq's Garage

Ok I will throw my 2cents in here. I bought a set of SSIs for my 2.7 California 911 when it arrived in Virginia. When talking with John at SSI, he asked me to measure the flanges which he said should be thick because of the CA thermal reactors. He was right and he sent the thick flange 3.0 version with the O2 bunge and "gasket protectors" (flanges that go up in to the head).

Prior to doing the 3.2 conversion, I called John about using the SSIs and he said that they would work fine, just use new gaskets and bold them up. Which I did.

2 local track hardended Carrera owners have driven my car (the only difference to drive train is they have to run the stock exhaust because of emmissions tests) and can not believe the difference even given the wieght advantage I have.

I attribute that difference to the SSIs as no other mods have been made.

FWIW: the exhaust will not get around the gasket protectors as long as new metal type gaskets are used. You can alway cut the protectors off, but that would be more trouble than it is worth.

RoninLB · 05-27-2003, 09:21 PM

Quote:

Originally posted by Mikkel
Ronin

You mean you have thick flange SSI's on a 2,7?

Yep !!!

OK.. Marc did a good reply.. saved me on that one..

BUT, I would never consider cutting off the gasket protectors.

If I had a 3.2.. the first thing I'd do is find correct gasket protectors/collars to blend the heads into the tubes.. and
hope ing, for a maybe, that the "pulse" is cleaner.. WTF ..........Ron

dickster · 05-27-2003, 10:59 PM

i guess mikkel is saying that flow isn't smooth from the exhaust port - i guess thats the price you pay having small id tubes.

can't be THAT great for power though, shows how bad the oe are, or the cat.

you guys dont use a cat. with ssi's do ya??

RoninLB · 05-28-2003, 01:01 AM

Quote:

Originally posted by dickster

- i guess thats the price you pay having small id tubes.
-can't be THAT great for power though,
-you guys dont use a cat. with ssi's do ya??

Probably high end HP expense.. but I wonder what the increased velocity of the exhaust would do for mid-range torque?

and most tracks in the US don't allow big blasts at the top end as Europe does, to my understanding.. so mid range torque does matter, IMO. but I don't know about the SSI on a 3.2/dyno wise.

and no routine cat action, or better said, un-action

Brad Roberts · 05-28-2003, 10:22 AM

OK.

They fit fine. Bolt them up using STOCK 3.2 gaskets. Below is a pic of a 3.2 set. I point out the difference between the two. Both are thick flange.. but one of them gets a "beveled" edge on the outside and the other gets a "beveled edge on the inside.

3.2 Liter 1 3/8 ID and 1.5 OD.

Here is the difference between the two. Very minor differences and most if is to fit the heads correctly.

B

Brad Roberts · 05-28-2003, 10:28 AM

Bigger is not better.

Time and time again "we" and others prove that 1.5 inch is just fine up until 300hp. You gain more mid range torque and only slightly lose 3-4 hp on the very top end over a 1 5/8 B+B race header. Can you feel 3-4 hp ?? I cant and neither can the people we test with.

Contrary to popular belief.. the cat doesnt hold back your exhaust. Again.. testing (on our SuperFlow dyno and.. Kevin Bucklers dyno... and... Jerry Woods dyno..) showed NO significant increase in torque or Hp when removing a cat from a stock engine.

The SSI's slightly outflow the stock 3.2 system. We bolt them on 3.6 engines all the time...

B

Steve W · Steve W's Garage

Brad, I had no idea there was a 3.2 set with a bevel on the inside and flanging to compensate for the larger id of the exhaust ports. Mine are the thick flange with the O2 sensor bung. Has SSI always been fabricating their sets this way? The sets that were shipped to me have the bevel on the outside, and I was kind of disappointed as Mikkel was to find that the pipes were much smaller than the exhaust port, allowing the units to shift around a bit and allowing the pipes to cut into the exhaust flow. That change in taper would make all the difference in flow. Is there a way to have my sets 'corrected'?

Brad Roberts · 05-28-2003, 11:27 AM

They are pretty easy to "correct" but the difference in flow is very very minor. You wont notice it and neither will the best calibrated "butt test".

This isnt the first time that people have been "surprised" to find the smaller diameter. I promise it doesnt hurt a thing.

Oh.. they cant "move around" as you suggested... the thick flanges on the studs prevent that from happening (ever)

All the HE's are built in house setup for a 2.7 thick flange. As the orders come in we weld in the small pieces I showed above..depending on whether the order called for a 2.7/3.0/3.2 or 3.6. Otherwise.. all the HE's are the same with thick flanges (02 bung is welded in during normal production)

Here is a shot of a thick flange HE. Order comes in.. we weld in the "insert" to creat any of the engine combos (2.7/3.0/3.2/3.6)

B

Wayne 962 · Wayne 962's Garage

We recently upgraded our catalog to reflect the newest and latest offerings from SSI:

http://www.pelicanparts.com/catalog/shopcart/911M/por_911M_exhaus_main.htm

John and Brad both yelled at us for not having the proper information, so we spent a bunch of time updating the catalog. I believe that just about every other vendor that sells these has incorrect information.

As for the 1.5" pipe diameter question? I believe that to obtain the maximum HP out of your 3.2, you would probably want to go with 1 5/8" pipe diameter headers. This of course would be really only applicable to race engines, as you would lose your heat. You wouldn't want to install SSIs on a race car regardless, because of the extra weight (I would recommend something like a set of 1 5/8" Bursch headers). As Brad said, the gains from replacing the convoluted CAT-style exhaust are dramatic enough on the Carrera - you're not going to miss that tiny percentage from the smaller pipe diameter. All in all, a very good upgrade (technically, for off-road use only).

-Wayne

dickster · 05-28-2003, 12:59 PM

Quote:

Contrary to popular belief.. the cat doesnt hold back your exhaust. Again.. testing (on our SuperFlow dyno and.. Kevin Bucklers dyno... and... Jerry Woods dyno..) showed NO significant increase in torque or Hp when removing a cat from a stock engine.

got disagree there brad.

i'm not into "butt dyno" figures so i had my 3.2 dynoed before and after fitting premuffler in place of cat. and then with sport muffler - theres even a thread on it!! we got 8hp swapping the cat. out for the premuffler.

and thats in line with comments in BA's book.

i dont believe ssi's are worth the money on a 3.2 unless your HE's are shot anyway.

jmho.

Brad Roberts · 05-28-2003, 01:23 PM

No problem Dickster..

I can adjust tire pressures on a DynoJet pull and get 6-8 HP..LOL

Did you test with a straight pipe and the silencer ?

*Most* people wont feel a difference until 12-14 hp is made. People like to think they can feel 6-8... but torque rules. You feel torque. Most of us speak with our wallet "I paid XXXX.XX and bought 6-8 HP".. I can feel the difference... Yeah..right.

B