Macfreak007

Mavfan, pretty cool video. I am glad you have found rennlist, and it is interesting to see you learn from your mistakes in the video. do you have a 924s and a 944?... as I see in the picture...

stefon

hi guys !

great video , i had learn some thing with it ! :$

Fishey

You have major problems with your N20 if you are shooting a 75 shot and only getting 30whp. I am not sure if the 924S has knock sensors but if it does my bet is that your car is running so lean that the knock sensors are detecting knock and retarding the crap out of your engine. I run a 55shot and saw around 50whp & 70wtq gain with a problematic nozzle setup.

flosho

Dry systems don't usually make the same amount of power as a wet, or direct port system.. Maybe not as dramatic... But then again, he made the 30hp gain, with the exhaust cutout open(which loses 30hp)?

Fishey is yours a wet system?

mavfan

yup i was loosing around 30 hp when i dyno'd the car this is what i had to say on my website:


"In all we did three dyno runs with the 924s. The first one (Blue) we ran her stock with no NOS and the Exhaust Cut-Out closed. We got 137hp and 131 torque.

Then on the second run (Red) something EXTREMELY weird happened. We opened the Exhaust Cut-Out for a free flow type exhaust (still without NOS) and we LOST 35hp and 37lbs of torque!! This was a horrible setback for our project. It means that since we had the exhaust open for the drag races at Gateway, we were loosing more than 30hp and torque! For anyone who does not know, gaining 30hp from a performance mod is extremely sought out! So all it means is that if we have time we have to cut out the exhaust cut-out and reinstall normal piping. So our effort and time was a waste... But it does mean more time at the drag strip to get the new 1/4 mile times, so its not that horrible!

So for our last Dyno run (Green) we closed the Exhaust Cut-Out and opened the NOS! Everything went much quicker and we came out on top with 168hp and 200lbs of torque! But as you notice the bottom graph is of the air to fuel ratio and for the first two runs its at a standard mixture of 12.9, but on the green one where NOS hits all of a sudden the mixture is way to lean (15.4) almost leading to detonation which means my engine could literally have exploded. So we searched over the engine to find out why this was occurring, and one of the fuel pressure lines had come undone at an unknown time. Because this happened the computer does not know how much fuel to be adding for the extra air coming into the cylinders so the engine runs dangerously lean. Another factor adding to the problem is the fact that Zex tells us which nozzles to use with the NOS system. And the way they had us set it up went like this. For the 55hp shot you use a small nozzle for the NOS being injected into the car and then a big nozzle going to the Fuel Pressure Regulator (FPR). Then when we switched it for the 75hp shot, you basically switch the nozzles. When installing it, i knew it didn't make sense, but that's what it said. Common sense should be used here because if your going to be using more NOS your going to have more pressure in the fuel pressure lines which a larger nozzle can handle. And visa verse. So to fix this we have to zip tie every connecting point between the fuel pressure lines to make sure that when we use NOS again that it wont blow one of them off. "

Fishey

Yes, I run a wet shot.

I am sorry for the mis understanding the 30whp gain was with the exhaust cutout open. So in theory you should have seen something like 60whp and given that your line came off more could be possible. It sounds like its re-dyno time if you ask me.

Bret 944

From what I'm reading, the NOS run was with the exhaust cut-out closed.

mavfan

i would like to redyno it, and i will, but not now, it cost $70 for 3 runs, they wont let u just do one run...

TRWright

15.4?!?!?!? on a wedge?!?!?!

mavfan

yeah it was "closed," but it doesn't seal up or anything, it was always loud no matter, so the vacume that was there, was not when the bypass was in there, thats why i took it out and installed normal piping again. so i guess it could have gotten back some of that 30hp that it lost when it was completly open, but that vacume that these cars thrive on certainly was not there

mavfan

what do u mean by on a wedge, and yeah it was running lean.

Jakerx

ok, this is NOT a flame. i am just trying to be honest...i applaud the effort. although please tell me why you purposely call nitrous oxide NOS when you know it's wrong? that doesn't make any sense. you want to dumb yourself down so idiots can understand you? anyone who is not a complete moron when it comes to cars will know what you mean when you refer to "nitrous." how old are you again?

the speakers imho are not a problem. the neons, get rid of those. how can you be anti-ricer yet you still have neon undercarriage lights on a 924????

also, think about this everyone. the 30hp increase from a 75 shot is not to be unexpected. that 30hp gain was rwhp...not hp at the fly. add on top of that that it was a dry setup and not wet, and you understand why the increase was not closer to 75.

and yes brett. fishey was wrong. the nitrous run was with the exhaust cut-out closed.

edit: ok actually, on 2nd thought, this is a flame. who the hell puts neon lights on a frikn 924

Fishey

Nitrous (all kits) are rated at RWHP.

flosho

Really? I guess I never thought about that, I just assumed a "75 shot" at the flywheel.

Wait, how do they do that, because not all kits are for a specific car, so drivetrain loss is different. Like the mustang kit can be used for a SHO, well one is FWD and the other is RWD, so theres a difference, but if its engine rated, it works out better..

Jakerx

ok my mistake. but why? all cars have different drivetrain power losses. that doesn't make sense. oh well. but at any rate, it being a dry system and not a wet system makes a big difference.