92lx

I have tried to research this for days with no clear answer in site so I'll get on with my question.I have a poor mans type r motor in my car which I'm sure everyone knows is a gsr block with a b16 head it is mildly built with the following parts

Mahle 12.5:1 pistons
Bored .20 over
Eagle h-beam rods
Supertech valves,dual springs and retainers
Crower stage 1 type r spec cams
Port and polish and a 3 angle valve job
Skunk2 pro series intake manifold and 68mm pro series tb
Rc 440 injectors
Skunk2 composite fuel rail
Aem fpr
Walbro 255lph fuel pump
Pwjdm power chamber intake
Now my question is,will 10mm difference in exhaust piping make a difference say between 60 and 70mm ? Thanks before hand for any useful info cause I just need to get the exhaust work done to finish the build.

93egSLEEPER

Are you worried about noise? 3" has proven itself to provide the best power, but it comes w/ more noise. IMO a 2.5" exhaust w/ a long resonator and a resonated muffler is perfect for DD street builds. Mellow tone, but still allows for good all around performance.

92lx

It's really not the noise that I'm worried about I'm thinking about getting the skunk2 megapower r catback which is a 2.75 inch exhaust.

93egSLEEPER

That will be fine, it is on the louder side but if you don't care about that you should be happy

Freemananana

iTrader: (3)

Not sure how much the Skunk2 is running price wise or where you are getting it from. But there is a seller here on HT that I got a 3" Thermal R&D exhaust from for $579 shipped. PM if you are interested. Very high quality, 2 day shipping, and it's 3" OD pipe. Very high quality stuff.

92lx

I'm getting it through a company called lightning motorsports for $543 shipped.

92lx

Now I just need to figure out which header to go with I'm really digging on the RMF narrow header.

93egSLEEPER

PLM toda rep. The RMF narrow is a good choice as well, but the toda has shown better gains on the 1.8's

Also, looking at your build list I would like to offer some suggestions, take them or leave them. I don't know if you're already building, have built or have bought parts.
1. You don't need an aftermarket fuel rail. Save the money
2. I would run the PerformerX IM over the S2, it will spank it.
3. RDX injectors will beat the RC's on this build
4. The power chamber intake is for looks, a 18-24" SRI w/ velocity stack will make better power
5. What made you land on those cams?
6. It's your car, not mine, these are just things I would do f it were mine. Have fun.

92lx

I bought this motor in a gsr that was in rough shape for $450 with only 5k on the motor I already have everything on the motor besides the intake,fuel rail,fpr and throttle body I have the injectors laying around from a trade I did some time back and the cams was already in the motor.

DDTECH

You'll want more Exhaust Velocity, The General idea is, everything past the merge collector is a restriction to a point. Ideally you'll want the most free flowing exhaust, there's been plenty of dyno / track test and good results to show that a 3'' exh isn't too big for a street app, regardless if its a b16 or B20.

A nice header, like Andy mentioned, combined with a good well put together exhaust should give you ease on the ears, and power.

92lx

Thanks guys I really appreciate all the info you guys are giving me it's a huge help.

SamTaylor510

I built the 3" exhaust on my 2000 SI from mandrel bends and straight pipe. I run an 18" x 6" round Magnaflow under the console area and a 3" Oval in/out Magnaflow at the back. Car is still fairly loud. With an N/A car you wont have enough exhast volumn to take much of the sound out, wspecially at lower rpms. . If you boost it, it will be fairly quiet as the exhaust volumn increases and allow the mufflers to work. I installed Car Chemistry Muffler insert in my exhaust, 3" x 1 disk. It plugs right into the exhaust right after my downpipe and before the mufflers. It causes a noticable drop in sound and did not hurt the performance. You may want a two disc in an N/A car.

EsotericImage

iTrader: (8)

As long as it has a good collector thats at proper length and merge, everything after that on a 3" has very low restrictions.

Im using the toda rep to a 3" vette hi flow cat, 2 vibrant 18" resonators and a magnaflow oval muffler. still loud as hell and has some rasp in mid torque rpms. I know the Vibrant streetpower muffler has alot more perforations then the magnaflow, but im wondering if it will do anything with the sound and rasp.

Engine is a built 11.2:1 B20 P8R

92lx

Like I said I really don't care about the noise I'm more worried about the power it produces but this is great advice though and I appreciate it.