The truth about 3inch exhausts on Na Cars

[LilMissMkIII]

These taken from the Dyno Day this past Sunday??

Shame i couldn't make it, looked like a good day!!!!!

 

[7MA61]

These taken from the Dyno Day this past Sunday??

Shame i couldn't make it, looked like a good day!!!!!

yep, I saw the cruise drive past twice, it was tempting to jump in the car and give chase but was having a great day talking shit at the dyno day. Plus its very cold to drive my car with the windows down to escape the petty fumes:nono:

 

[Nick M]

The thread was just made because my graph clearly shows that the common misconception of the loss in bottom end power with a bigger exhuast, yeah the gains aren't huge but it still hasn't lost power.

I would normally give up, but I don't ever do. It isn't a common misconeption, it is how it is. That is what I am trying to stop.

Don't make me find a low mileage 7M just to show everybody.

 

[AGlobalThreat]

I completely agree with you that for street use and for 99% of NA owners on here that a 3 inch exhaust on an NA car is just silly. Comparing my 7mge to 99% of 7mges on this forum is also pretty pointless because not many are anywhere near as modded the only exceptions being the guy with the homebuilt ITB kit and the 101mm stroke 7mge.

No. I had my current 3" straight mandrel bent catless exhaust on my car when it was NA. It was not over bored or stroked, I just had lots of weight reduction and lots of bolt on/small upgrades, and the exhaust was PERFECT. All these people talking shit about 3" exhausts on the 7mge, you've obviously never TRIED it, or else you would know how perfect it is for the engine. I would not recommend it for a slow bone stock auto (No offense), but anyone with a healthy 7mge will definetely benefit from a 3" exhaust.

Tune the car with the 3" exhaust to shut the rest of these people up.

The only low end loss you would find is so low in the RPM range that it won't even show up on a dyno. ARGUING A 3" EXHAUST ON AN NA IS POINTLESS IF YOU'VE NEVER TRIED IT.

 

[Nick M]

Car Craft magazine, a mag dedicated to domestics tested a 2.5 vs 3.0 inch exhaust on a 383 CID engine. It produced 462 lb/ft of torque, and 473 hp. The 3 inch system went up 11 and 11, peak to peak with 5.1 average torque, and 4.7 average horsepower.

Small gains, even on the stronger engine. But this isn't news, you have been told and told. This is actually rehasing tech on their part, as new kids always enter the hobby. So on your 7MGE, you gained nothing, and probably lost.

 

[BorHor]

The only cool gain I noticed was easier start up.

 

[Nomad707]

sorry for gravedigging.. but i cant but help to hear the sound of your supra.. its BADASS.

i had a 1993 kawasaki ninja ZX-7 (750cc 4banger) i took off the exhuast.. (straight pipes with NO muffling)

Seemed to be as loud maybee a tad louder then this supra...

regardless.. this mk2 7m powered supra is fucking sick.

 

[Fuzz420]

I'd say louder.
I was there during said dyno session.

He definately had a gain in horsepower and torque without a muffler.
I've got to say, out of all the cars that I recorded dynoing that day, this includes some insane, higher horsepower Supras, his was hands down the loudest car at WOT without a muffler and 2.5". :icon_bigg

Now Aaron, tell us all if it was worth it without the muffler? :biglaugh:

It was worth it, if you have to cover your ears up for a dyno run from a n/a car, that means its loud :naughty:

 

[BLACKCAT]

Have you received those BC 272 cams yet?
Do you think you will get into the 130 RWKW range with them?