I just had a 5177 kit with a 100HP shot installed in my 02 M6 Z28 today. I went with a single nozzle installed at the bottom front part of the lid, like this...
http://solo2.abac.com/avigdor/temp/Z...le%20front.JPG
I also had an MSD window switch installed along with a throttle position switch and the standard FP switch, the stock MAF has been descreened. The 15LB bottle is mounted in the spare tire well. While testing the car in the shop the system worked perfectly. However once we took the car out to try it on the street the car was surging violently, almost like you where turning the switch on and off (not like a low NOS pressure surge). So we start trouble shooting the following with no improvement at all (the bottle was full @ had plenty of pressure)...
1) bypass FP switch
2) bypass MSD window switch
3) change arming switch
4) change NOS solenoids
5) change stock MAF to an aftermaket MAF
6) change NOS relay
7) change NOS nozzle
8) verify wiring and grounding
9) verify bottle weight and pressure
10) verify NOS lines
After 3 hours of trouble shooting we called it quits. The system was installed by one of the largest speed shops in Toronto, so they know thier sh_t and they where stumped. They are going to call NOS tech support on Monday, I thought I'll bounce this off the forum members here to see if this is a problem that anyone has encountered.

Does any one have any ideas???

[This message has been edited by vmax1500 (edited July 06, 2002).]

[This message has been edited by vmax1500 (edited July 06, 2002).]

 

Looks like you have the nozzle in the outlet of the air box lid, impinging directly on the MAF. Could be a case of inadequate mixing of air and nitrous. That would throw off the MAF sensor, since the wires are only sampling a small part of the flow, and the flow needs to be extremely uniform and homogeneous to allow the MAF to achieve any accuracy.

The beauty of the NOS recommended install, a nozzle in both sides of the airbox base, is that it allows for some degree of mixing of the air and nitrous before it leaves the box and hits the MAF.

Definitely possibilty that is the problem. Not sure why it worked in the shop and not on the road.... so it may be something else.

------------------
Fred
94 Formula A3: 381/TH400/N2O

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11.513@115.59 on motor; 11.162@127.67, 1.643 60' on a 125-shot. Going with a 275-shot this year

[This message has been edited by Injuneer 94FormM6 (edited July 06, 2002).]

 

Thanks for the reply...
When I say we tried it in the shop, I mean the solenoids are opening and the nitrous is flowing fine. The shop did not have a dyno so there was no way to check if the car was actually responding to the shot. That's why we tried it on the street, with little luck. I got the idea of installing the nozzle under the lid from a couple different boards. Is there anywhere I could install the nozzle without having it in plain sight? Is it common for the system not to function properly with my nozzle placement? I would rather run a single nozzle if possible.

 

Here's some more info...

Details of my car...
-2002 M6 Z28
-LM cat back
-FTRA+LID+K&N
-B&M Ripper
-SS 10 spoke 17"s w/F1's
-20% tint all around
-dyno @1450 miles with bolt-ons 323HP & 340LB/FT
-best ET 13.3 @ 107 & 2.1 60ft

We started with 13600 nozzle and then switched to the 13500 nozzle and there was a very little difference. Both times the nozzle was aimed at the MAF.
http://solo2.abac.com/avigdor/temp/Z28/4nozzles.gif
I doubt I'll find someone with a lid locally (Toronto), so I'll probably try plumbing the nozzle in the conventional location. Worst case scenario, I'll plug the holes if this does not work. I think I'll end up buying another lid in case I have to go in for warranty work.

[This message has been edited by vmax1500 (edited July 06, 2002).]

 

Not familiar with too many 5177 installs, but a buddy of mine just followed the NOS instructions and put the nozzles on the side of the box on his 99 SS... and he's running 10.8@125 on a 125-shot. You might want to try posting on the LS1 Tech board if you don't get more info here.

Fred

 

Here's a story with a happy ending
I just got back from a weeklong business trip to Seattle, so that explains my absence from the board. I spoke with the shop that installed my NOS kit and they spoke with the folks at NOS and they said the problem with my setup was that we where freezing the MAF. So I went back to the shot tonight and they spun around the nozzle so that it was facing the front of the car. We took it out for a trial run, and all I can say is...
HOLY FREAKING MOLLY (trying to stay G rated here)
2nd gear spins like crazy to the point that it's scary, 3rd spins like 1st did before the spray and 4th will chirp if you shift hard. Keep in mind this is only with a 100HP shot.

PS. on a side note, while driving home on a deserted freshly paved 4-lane country road I decided to try a 2-3-4 run. I kept my foot in it through 2nd, spun all the way through 3rd and chirped 4th... just then I see a cop car approaching in the oncoming lane. I jump on the brakes and do my best to slow down. I look in my rear view and the cop slams on his brakes and does an 'action movie' style 180. I proceed to pull over and wait for the cop to catch up. I knew I was toast. He comes to the car and says he had me doing 147 in a 60 zone on the oncoming radar. I just said 'holy smokes'... he was young guy about my age (~30) with a crew cut and a goatee... as he was saying this he laughed and said this would not help out my insurance premium. He asked if I was trying out the car, and told him that I guess I chose the wrong spot to open her up. He saw that I still had my temp plate stuck to the windshield and knew that the car was relatively new. He proceeded back to his car with my license in hand, I looked back out the window and asked if I would still have a driver’s license when he got back, he laughed... I was serious. When he gets back to my car, he tells me before giving me my ticket that I better pay this right away and that if he sees me taking this to court that he’ll be knocking on my door. He gave me $42 ticket with no points for doing 15 over, I told him... "G-d bless you".


[This message has been edited by vmax1500 (edited July 17, 2002).]