I saw that article about the vortech. they didnt even tune the damn thing, no wonder it only spit out 80wheel. They shoulda taken that thing to a tuner to fix up the fuel and get much better numbers than the wimpy one's they got. On a side note im stuck on 91, but I also run pig rich with my N/A mods. Only difference is im at altitude.

 

Correct. 91 octane is bad for making power on all cars, but
it should affect a highly modified turbocharged car MORE than
a near stock naturally aspirated car. Instead, it seems to be
the other way around with the 350Z/G35 according to some
folks who keep bringing up the 91 octane issue.

If you look at dynos, on a turbo car, instead of getting 20 hp from
an exhaust, you only get 15 hp due to 91 octane.

Whereas on the 350Z/G35, instead of getting 15 hp from an
exhaust, you get 0-5hp...

Look at the advertised HP ratings that are supposedly based
on dyno tests from the manufacturer's homepages (Borla, Stillen,
etc). Then look at the real life numbers people are getting on
the dyno.

I'm just not used to dumping thousands of dollars into
"performance" mods and not gaining much hp, that's all.

 

There is a good reason why the delta gain on a NA vs TT setup is flipped. The reason 91 pump and a free flow exhuast may gain little is due to a "mid band lean" conditon which results in slight knock , which causes the OEM ECU to pull timing on the NA setup.

Now on a tuned TT install the A/F is tuned richer to accomodate the boost. So if properly tuned the freer flowing exhaust is less likely to cause the ECU to pull "addtional" timing.

 

there are very very few impartial dynos that prove any performance improvement with any aftermarket exhaust. you got one? oh... no? guess not.

the common experience with a z is to dyno over and over and at best run see a slight hp gain at WOT, and a torque and hp loss in the low end. this is while running *whatever gas with *whatever variable... then *whatever personal opinion added to it. the bottom line is that you can't do much improvement on something that's near perfect. the stock z exhaust is tuned very well.

all that said, FI can see improvements opening up exhausts on all kinds of cars that otherwise the same mod would degrade performance. rx7s, civics, accords... all of these cars can benefit greatly from 3" pipes while boosted, but would absolutely kill it otherwise if N/A. wow.

 

It's the backpressure myth again...
Backpressure = bad
Over sized pipes = bad
proper length and size pipe for the application = good.

If the Borla system is over sized for the NA motor, loss in gas velocity will reduce scavenging, this reduces "on cam" power.


Lets all keep in mind the Z was designed to be a LEV and ULEV, depending on year, and the motor to last 200k miles. The factory is gonna do everything they can to meet that goal. I think the key to making more NA power is locked up in the computer.

Chris

 

One thing is sure the OEM CATs don't help exhast gas scavenge and they are the main restriction . But if they are removed or reduced to HFs ,a lean mid band condition can occur , which will cause the ECU to pull timing . So for anyone expecting gain from CAT removal (on 91 pump) , the ECU should be modified to alleviate the lean condition. Of course this whole process is illegal in Cali, but I won't tell if you don't

 

So for anyone expecting gain from CAT removal (on 91 pump) , the ECU should be modified to alleviate the lean condition. Of course this whole process is illegal in Cali, but I won't tell if you don't [/B][/QUOTE]
How about with 93 octane (that's what I run)? No timing problem? Just curious about your findings.

 

Don't know for sure, but it is much less likely for the OEM ECU to pull timing even with CATS removed. Those 2 pts make a world of diff, since the ECU trys diligently to keep the engine on the verge of detnation for efficeny reasons and it is designed for 91 out of the can.

 

SCC is crap. Primedia is known for kissing *** for advertisers only. Their magazines are all fluf. I gained 13 hp dyno proven by the exhaust.

 

borlas an advertizer, wouldnt they be pissing off their advertizer. nice theory though.

 

Thanks for the info man. Anyone else have before/after dynos with this exhaust????