rdewalt

iTrader: (1)

I recently installed a NX wet system and made a few small street runs just to make sure the system would work. Last week I took it to the dyno shop for some logging. I put down just over 110 HP and 150 FT-LBS on a 100 shot. I retarded the timing the full -10% or around 2* to 3* with my Predator, timing held between 23.5* to 25* no KR and all went well. I sent the dyno results to my tuner and he felt I was running too lean at around 13.0 to 1 average. So he richened the tune up to average 12.0 to 1 and took 2* of timing out of the tune. Now I am getting some KR from .9* to 1.9* with 20* to 23.5* of timing after the KR . I made early morning runs to try and duplicate the same weather conditions as the dyno runs. I do not get KR every run but out of 3 back to back runs I got KR on 2 of them and it got a little worse each run. I am even getting 1* to 2* of KR running this tune all motor. My question is has anyone else had problems with KR when running this rich. I have also been getting a little back firing out the tail pipe upon deceleration; according to other threads I have read this is a result of unburned gas in the exhaust system.

Matt@HSW

iTrader: (14)

Are you sure it's not false knock? How was the A/F modified for the wet nitrous kit? Did you try swapping out fuel jets to richen it up first? What is your A/F NA?

Matt

rdewalt

iTrader: (1)

A/F was about 13.2 to 1 on NOS and 13.7 to 1 all motor before he made the change, and he set the all motor tune to run at 13.0 to 1 and the NOS tune 12.0 to 1. They are able to make the changes to the computer with a program like HP Tuners then he e-mails me the tune and I upload it into the car with my Predator Tuner. I installed the all motor tune and made a few runs and no KR to this point I am going to do some more logging to be sure. He seems to feel something is banging maybe the exhaust, but I don’t know why it would not bang with both tunes. Someone told me a while ago you can get KR from running too rich just as from running too lean. I was wondering if others have had similar problems. I was a little leery about changing jets as I am new to the Nitrous game and did not want to deviate from NX guidelines.

2nasty

HEY MATT AT HSW. do you have a cell phone number i can call you on right now. i have some questions about a kit i am going to buy from you

Matt@HSW

iTrader: (14)

So you have your one NA tune and then you have a tune for the juice, correct? So you are flashing between them before you spray? You are only getting KR while on your nitrous tune, never on your NA tune? You are correct, if something was banging around you would see it on both tunes. How much timing are you running on both tunes? What octane fuel? Did I just ask enough questions LOL?

Matt

Matt@HSW

iTrader: (14)

Sent ya a PM.

Matt

Nitro Dave's Nitrous Outlet

iTrader: (25)

First of all.I would have set the NA tune for about 12.5. Then I would have set the airfuel for nitrous to 11.8-12.1. I would suggest tunning the nitrous airfuel by changing the fuel jets in the nozzle.This is the best and safest way to get it right.
Dave

Ravenous T\A

iTrader: (12)

Some dude was telling me that KR (as in turning it off)is not needed in a N20 tune?? This same guy also says that I dont need my timing set at 26 degrees on my 150 shot? Im calling BS but I wanna hear it from the experts

Matt@HSW

iTrader: (14)

BS. Well sort of. Unless you are running a high enough octane fuel and you know it's quality and the car has been tuned for it. A lot of stand alone engine management systems don't have KS per say, so you don't need them in certain situations. You would have no reason to turn off your knock sensors.

Matt

Ravenous T\A

iTrader: (12)

I know, especially for a street car running on 93 octane all day long in changing Texas Weather, hot one day cold the next. Having the knock turned off is asking for trouble right?

Matt@HSW

iTrader: (14)

Big Trouble! LOL.

Matt

NitrousDirect

iTrader: (1)

Yep sure is.