hamlet9634

So a little back story for this. Some of you know that I have my brother Sherwin's car now (Docofmind). He had done a bunch of things to the car, none of which I had followed too closely. I knew he had Injen intake, some sort of headers, and a JIC "magic" exhaust system, along with some other non-power related things. When I first got the car and drove it, it seemed slow to me. Given that I had never driven an s2000 before, I just figured that's the way these AP1's run. I had it a couple months, and was looking for more power. Before I did that, though, I had the car sent to a local mechanic for a tune-up. He ran the ECU (no codes), changed the plugs and fuel filters, air filter, etc, then gave me back the car and said "that's how s2000's are".

So the car ended up at the skunk2 headquarters (was originally supposed to be the prototype for the Kraftwerk's AP1 supercharger kit). But when they got the car on the dyno, it made 136 hp at the wheels! We ran every possible diagnostic, checked the cat, compression and leakdown, etc etc... couldn't figure out why the car sucked so much, and why it was running a:f ratios of 9:1. Right before they gave me back the car, I asked them to change the exhaust because the JIC was insanely loud and horrible sounding and i absolutely hated the thing anyway.

So the skunk2 dual stainless system went on the car, and we threw it on the dyno just to get some numbers before I drove over to Church's to see if he could figure out the problem. Well, I was already happy because the system looked much better, and it was quieter with the silencers OUT than the JIC was with the silencer IN, and it had a nice throaty rumble. Here's the kicker : 207 whp. This corrects to a dynojet value of about 219. That's PLUS 71 hp just by switching from JIC to Skunk2 exhaust. We did another dyno run with the silencers in to see how much power I'd lose to have a near stock volume car, and guess what.. it makes the EXACT same power with the silencers as it does with them out - the curves perfectly overlap.

moral of the story? well there's a couple. Anyone with a JIC exhaust do yourself a favor and get rid of that piece of utter crap, and skunk2 gets a customer for life. They really helped me out, and did the diagnostic work as a favor to me because of everything sherwin contributed to our community. I feel like I have a whole new car... sorry to ramble

FF2Skip

Happy to hear the car runs better. I've never been a fan of JIC stuff, but I can't imagine the design caused that much of a choke. Isn't it possible that something broke off and was impeding the exiting airflow?

mattfeet

Yea, there is no way even an ebay exhaust would cause that much restriction unless something was broken/jammed. I dont mean to rain on your parade, I just think there was something more wrong than what you knew about. Glad you got it running though!

-Matt

hamlet9634

ofcourse there was something jammed guys. The JIC magic exhaust was crap to begin with - the silencer they use is about 1.5inch inner diameter.. and it was such a piece of crap that the silencer collapsed on itself on the inside. You'd have no way of being able to tell there was something wrong from the outside. But you aren't raining on my parade at all.. the truth is that I now have 50% more horsepower than I had yesterday.. it's an incredible difference. I'm so happy

FF2Skip

[QUOTE=hamlet9634,Dec 1 2007, 06:19 PM] ofcourse there was something jammed guys.

hamlet9634

SD as in south dakota or san diego? I'll be in oceanside that same weekend (20 min away from san diego).. and if it's san diego, at least you get a couple days of nice weather.

and yes.. i lived in chicago for 5 years and nyc for 5 more.. so i enjoy every day of weather out here in sunny southern cali.. top down every freaking day! even when it's freezing (freezing out here is 60 degrees, by the way.. )

FF2Skip

San Diego. More specifically, Coronado Island for a military gathering.

I lived in Yuma, AZ for 13 years. San Diego is cold weather.

A51_AP1

I've been seeing more and more threads about the JIC exhaust killing dyno gains. one guy had 179 hp, and put the stock exhaust back on and going back to 203hp. that is crazy, and to think i was going to get a JIC exhaust :-P

LostMotion

JIC exhaust is utter crap, read many tales of it taking 30hp from an s2000.

Enthralled

someone in my section worked for Skunk2 and said they don't do much testing on their parts..don't get too excited about their products.