the numbers i am showing you guys were not the lowest and higest. they were the highest of both. the way the dynos was working that day and with the cars warming up and all, it seemed that the 1st run was the lowest and then higher and higher until the 3rd and 4th were almost identical.

 

[QUOTE=jjellyneck]I hate dead dynos.
On a different note, several guys have said that cats or test pipes combined with a plenum give some noticeable gains. So...you you got even more performance out of it?

I would say DEFINATELY!!!!!
I just don't know now which contributed the most.....
I installed the Megan Racing resonated test pipes. I have the Gruppe S Y pipe, stock mid, and the Greddy rear muffler.
No rasp....but at around 4K.....It is kinda LOUD!
I swear....the stock cats must weigh 35lbs.........

 

That'd be fine, but I can also show you dyno data that says otherwise.

Then there's the question of how the dyno runs were conducted. The single most important factor would have been coolant temperature monitoring. You can gain/lose 5-10hp from a 10deg. shift in coolant temp.

BTW ... I'm only refering to the Z-tube (no CAI) here.

 

I can assure you that the coolant temp was monitored in this last test. I was holding the tester many times and we'd only start the dyno test when the collant temp was at 192 degree F.

 

yes, i can second that. we did not run until coolant temp was 192. and that is partially the reason we were there dyoing from 9 in the morning till 8 at night. and lucky me got to go last. but i did get the highest N/A numbers of the day so i cant complain. =)

 

[QUOTE=OldVFRGuy]Hey vfrguy, I bought those megan pipes too. I haven't installed them yet.
So you say it's not raspy until you hit 4k but do you smell any fumes in the cabin? or does it stink that bad as to where a cop will pop you for having removed your cats?

 

[QUOTE=Dizz]I had those installed, and although they sounded great, I thought the smell coming out the back was pretty nasty and was a dead give-away. I also feel more comfortable driving here in CA after switching to hi-flow cats considering the strict laws. The hi-flow cats also sound great but don't smell any worse than regular cats.

IMHO, test pipes might be fine on a straight up sports car, but not a luxury coupe with Infiniti badges.

There are lots of threads about this on various forums tho, so for more info try a few searches, no need to derail this one any further

 

[QUOTE=copbait]When did helix start making a Hiflow cat?
You have a link?

 

[QUOTE=Dizz]PM sent

 

That wasn't directed towards you guys, instead it was in response to Neffster's reply. I knew coolant temp was being monitored at the dyno day ... I suggested it along with the ECU resets. I was also glad to see good consistancies between runs as the result.

 

PLEASE, PLEASE, PLEASE, Somebody tell me where you get the spacer. Two or three of us have asked but everybody just keeps quoting dyno results.

Is there a web site or a secret code word that we, the uninformed (the unclean) need to know to join this most exclusive of clubs...the "I got a spacer and you don't" club?

 

try PM'ing 'Hydrazine' ... and don't forget the secret hand shake!

 

The cars were all sitting idle for over 2 hours, the results are posted below... The following shows a picture of a dynojet dyno showing a stock G35 5AT coupe, a 5AT coupe with the Z-Tube and P/C, and a 5AT coupe with the Z-Tube and Stock Air Box. The green line is the stock G35, the Red is the Z-Tube and Popcharger and the blue is the Z-tube and stock air box (with paper filter).

 

Looks like a little more juice with the Z tube. When I installed mine on an otherwise stock 6MT coupe, I did not feel a butt dyno difference, but I noticed that the power did not flatten out as much (or drop) in the upper RPMs. Just enough to note a difference.
neffster did a fabulous job in all aspects of the S. Florida dyno day...from eveything I've seen.

 

Neffster, do you have any dynos from that day comparing Z-tube vs stock on the same car? In my experience, these cars do not put out the exact same WHP. For example, in my first dyno, my car with a Z-tube was 219 WHP. On the same machine that day, another car with Z-tube and popcharger was 236 WHP. And we know that the popcharger doesn't give 17 HP gain. (Both 5AT coupes in 4th).