SSI's, first drive impression

Just got back from the first spin after the install of SSI's and Dansk stainless one out. First impression is the the power may come on a bit smoother and there may be a little more juice in the top half of the tach. It's not a breathtaking difference by any means, but I "think" I feel a little difference. The one HUGE diff I can tell is the amount and intensity of heat to the cab. I could roast me up a tofurkey in there. All in all, I'm happy with the upgrade.

Should have another dyno run in a few weeks. Since I have a baseline, we'll just see if BA was blowing air up our skirts!!!!

gratuitous Duck pic

[CarreraS2]

Isn't it supposed to be a 20+ hp increase?

Should 20+ hp be really noticeable?

Does it sound any different?

Sure looks nice, though!

[rfuerst911sc]

From what I have read they are worth between 12 to 20 hp and up to 30 ft. lbs, torque,I have them on my 83SC and I think I felt a difference also,plus knowing they will basically last forever it was money well spent in my opinion.I am interested to see your dyno results after install.

[911nut]

There seems to be increasing evidence here on the bb that SSI's are of little benefit to increasing HP and/or torque. This supports the theorey that the restriction is in the muffler.

[RoninLB]

Originally posted by Mark Wilson
Should have another dyno run in a few weeks. Since I have a baseline, we'll just see if BA was blowing air up our skirts!!!!

great

[Bob's Flat-Six]

How do you like the sound compaired to your other exhaust?

Bob, the exhaust note is deeper and a bit louder than the stock system. No bothersome resonance and not nearly as loud as the Flowmaster. As good as the FM sounded, I really like the more mellow sound of the Dansk. Guess I'm becoming an old fart as we speak......

Paul, I spoke with John Walker about muffler differences. He may correct me if I misspeak, but I think I understood him to say that he doesn't think mufflers make a big diff in performance. I'm pretty sure I saw a post from Steve Weiner where he said the same thing.

[nostatic]

I thought the difference was in cat v. no cat.

[coolbreeze]

we should chip in on the dyno just to see the true before and after results.. theres been much talk about the before and after thing but no hard numbers. you are a regular lewis and clark.

[Elfer]

Ive got SSIs and GHL one out on my SC. This is much louder than the stock setup and more responsive as well. Only thing I dont like about it is the resonance. I might go switch to Dansk and see the difference.

[nostatic]

seems like if there is an extra 30ft/lbs of torque, you'd feel that in the bottom half of the tach. Numbers will be interesting...

[k9handler]

I wonder this as well since all I run is the cat...need to get on a dyno I guess.

[John Velasco]

I have a ’76 911s currently rebuilt with SC cams. When I first bought the car it had what seemed to be an exhaust header that was used to replace the thermal reactors, these were not equal length. In addition to the pipes it had a Bursch exhaust. I replaced the pips with SSI’s and left the Bursch. I can tell you the car felt as if it lost hundreds of pounds, it’s responsiveness was much more acute and the top end seemed to go on forever. Needless to say it was worth every penny and the sound is very visceral and stimulating.


Bottom line is I love them.

jv

Mark

Congrats on your backdating.


I had the same experiences as you. It felt only a bit more powerful. Still there's no doubt that mine picks up revs faster. How's your's regarding that?

The aggressive sound is nice too

[911nut]

Originally posted by Mark Wilson
Paul, I spoke with John Walker about muffler differences. He may correct me if I misspeak, but I think I understood him to say that he doesn't think mufflers make a big diff in performance. I'm pretty sure I saw a post from Steve Weiner where he said the same thing.

Well, all that I can say was after I gutted my muffler and replaced the factory guts with baffles I never wanted to go back to the factory set-up. It made a much bigger change than replacing the cat with a test pipe.
It's a good feeling to know that now I can take that grand I was going to spend on SSIs and buy cams and get more bang for the buck.

[Mike Feinstein]

I've heard that SSI's can really make a difference, but primarily in the presence of other mods....ie., cams, port-matched intake, etc., (looks like JV above upgraded cams at the same time) In the absence of these other mods, I believe the performance difference is negligible. I'd think that a 30 ft/lb difference in torque would be quite noticeable (no imagination necessary).

The duck looks awesome.

I don't want to give the impression that I'm not happy with the SSI's. I still think it's the most sane/affordable performance upgrade available for the SC. I am purposely being very conservative in giving subjuctive test results until I get a little more seat time on dry streets - I don't want to discover that 30 foot lbs at the wrong time. When said I more juice in the top half, that was third gear acceleration from about 3000. I assume that's where the torque addition shows itself.

Thanks Mike!

[Rodney Nelson]

Mark,

Please hurry up, get on the streets and give us some more impressions of the upgrade. I have money in my pocket and a 83 SC in the garage and I am ready for an upgrade.

If the streets are still wet, get out there with a hair dryer, take the car out of the garage and burn some rubber.

Plus, how about some more close ups of the installed exchanger and muffler.

Thanks,

[RoninLB]

IMO,

an SSI install is a no brainer

[al lkosmal]

I have a 77 911S. When I bought it, it had the stock exhaust with the dreaded thermal reactors. First I replaced the thermal reactors those 3 into 1 replacements, then a year later I installed SSI's and a Dansk 2 in-1 out sport muffler. Definitely more power above 3000 rpm or so. I believe the difference you'll feel is directly related to how restrictive your previous exhaust was. My thermal reactored 2.7 was probably the low point in 911 exhaust design so the upgrade was noticable. SSi's are well worth it. Makes nice sounds too.