Random1

=============== STR Threads ===============

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=============== STR Threads ===============

What exhaust do you use? Header? Cat? Cat Back?

Car: 2003 S2000 AP1

Header: PLM (about 11 lbs)
Cat: Home made Berk like (about 7 lbs)
Cat Back: OEM cut at Y with V-band and down pipe (about 10-11 lbs)
SCCA Sound Rating: 97 dB measured at 2011 nationals on west course

Cat Back Options: Single using OEM resonator as muffler (about 10 lbs)
SCCA Sound Rating with Cat Back Option: TBD, guess it to be near 93-94 dB

PLM Header


Top view of PLM header installed


Home made Berk like cat, no CEL fix, used PLM test pipe with Magnaflow 200 cel/sq-in Cat


Down pipe attached with v-band


Option 1 - OEM resonator as muffler with OEM tip; Option 2 - down pipe


You can hear what the down pipe option sounds like in this video.
http://www.youtube.com/watch?v=t-3vuWZcav4

Just adding this to the end of this post for now to reflect my latest setup as of April 2012.

In preparation for the San Diego Tour with its 93 dB sound limit, I made a new cat back exhaust. I purchased this cheap ass funny looking twin loop JDM ricer muffler on ebay and it turned out to work nicely. It's light and very quiet. Apparently it's a clone of a Mugen muffler. This plus two pre-bent 45 degree stainless tubes, a v-band added up to a $150 exhaust assuming a free OEM cat back to start with.



I'll have to get some better photos in the day light. The total weight of the cat back is 20.5 lbs including two rubber hangers, front half 11 lbs, rear half 9.5 lbs. The big four inch exit pipe had to be cut off in order to make it fit. The two straight through passes through the can make for a really light and quiet muffler. I think my wife will like it. I can actually listen to the radio now. Even going under a bridge it's really quiet with the intake the dominate sound. When I get the car tuned I'll consider getting a final pull with the muffler on to see if there is a power hit.





The v-band was moved rearward to avoid the axle flange. I plan to run it with the rear portion removed with a down turn for local events and nationals.





Under Construction








Here is what the inside looks like. Fiberglass insulation will not last forever.



Here's the new down turn.

daverx7

Car: 2001 S2000 AP1

INTAKE: K&N FIPK
Header: Toda Torquie-kun
CAT: Berk 2.5"
CAT Back: Invidia with OEM resonator right after the cat
SCCA Sound Rating: 97.1 dB measured at 2011 Blytheville Tri-State National Tour

-Dave

ummpwr

so it seems like the best(lightest) cat back exhaust options are a full tit. like light spec or j's racing, around 9lbs. how much does the stock system weigh when you take off the axel back and weld on a turn down?

Eric


Car: 2000 S2000 AP1

Header: Berk
Cat: Berk hi flow
Cat Back: Berk UHV duel tit mufflers (25lbs)
SCCA Sound Rating: NA but ive never had problems when they measured 50ft away

Random1

I added the estimated weights to the other components on my first post. Sorry, forgot those. Cut OEM cat back weights about 10-11 lbs with down pipe. The optional back half weighs about an additional 10 lbs.

josh7owens

Car: 2000 S2000 AP1

Header: Toda torqie-kun
Cat: Berk 70mm
Cat Back: T1R 70r
SCCA Sound Rating: 97-98 DB
Price: header ($1200), HFC ($300), exhaust ($1000)= $2500

The toda torquie-kun is most proven header for low to mid range TQ, you loose 1-2hp at the top end but gain power in the mid-range. This is where you need it for a AP1 S2000. Posted below is a dyno of my car un-tuned. The dark line if of the car with just a intake and the 70mm exhaust. The read line is of the car with the header and high flow cat. As you can see the car did get leaner and is in need of tuning. 2012 ECU rule change will fix this and should show some nice gains. What I'm sharing by showing this graph is that if are on a budget a intake and exhaust sould be the first two power mods. The other bolt on power mods show little gains without tuning. Light weight it also a big reason for power mods on the s2000.

Some people think my car is to loud so heres a video from outside and inside the car.

http://vimeo.com/30284510




edit- Just wanted to add that if you put a turn down dryer vent on the tip it will be under 95 DB

Random1

97 dB is loud. I get comments all the time from course workers. 100 dB is the SCCA limit for sites that allow it. San Diego and some others limit to 93 dB.

bronxbomber252

The greddy TiC 70mm single, is what I have. For sound, a friend of mine had it on a CR with the 70mm berk HFC and said it come out to 91 or 92db, and when he took the axle back portion off at national tour events it came out to 96-98db, and knocked off a bit more weight.

User 121020

Car: 2000 S2000 AP1
Header: PLM, wrapped
CAT: Custom 2.75" inlet, 3.0" outlet
CAT Back: 2 custom cat backs (see below)
SCCA Sound Rating: 102dB & 97dB measured at 2011 Nats

Header: PLM with fiberglass wrap


Cat: 200 cell per square inch Magnaflow, 2.75" inlet, 3" outlet with SS v-band


Cat backs: Top is modified OE resonator section with a turn down tip that exits at the axle(97dB). Lower is 3" AL with 3" Vibrant AL muffler and turn down tip that exits at the axle (102dB). Obviously it's too loud, but will be modified to be sound legal. The AL exhaust weighs approx 3-4 pounds.

Random1

Any other differences beside sound level and weight? Power?

BirdShot

This is what I am curious of, could you actually FEEL the difference after installing the high-flow cat and headers? I had briefly talked with daverx7 about his headers on the AP1 and I remember him saying it made a noticeable difference in low end power. So could you tell your coming out of the corners a bit harder after these mods?

When I did headers on my E30 325i along with straight pipe in place of the cat, the difference was fairly noticeable, but only in the last 500 revs before redline.