In the 4th gen forum they were talking about running hotter plugs with race gas to gain some power.
http://forums.maxima.org/showthread....hreadid=200433

I understand that the point of higher octane gas is to prevent preignition. So, up to a point (maybe 70-80shot?), couldn't cars running nitrous run stock plugs and just run some race gas at the track to prevent preignition due to the hotter cylinder temps/plugs?

My reason for asking is because I only really plan on using nitrous at the track every once in a while, so I would rather not run colder plugs in my car all the time.
-hype

 

The theory sounds ok but you are swimming in unchartered waters. I wouldn't try that without having some instrumentation to monitor the results. This year I am using a S-AFC II and and OBD-II monitor/logger so I watch timing, air flow, monitor knock etc etc

My plan is to use a separate fuel tank, pump and regulator (which I have already mocked up and tested) just for the nitrous and using race gas (C16) 117 Octane. However I still plan on using 2 steps colder plugs, but I will also be using a 100+ shot.

I ran 2 steps colder plugs gapped at .035 all last year and really didn't notice any difference N/A except that it idled a little rough for the first couple of minutes when it was cold.

 

I agree with Jim. I ran race gas and 2 step colder all last year w/o any problems. There is not as much difference N/A as some people will have you believe. I personally prefer being safe rather than sorry. Changing the plugs in our cars, with practice, takes no longer than 15-30 mins at most. It is very little effort to keep from blowing a motor IMO.

If you want to run colder plugs for the track, just change them before going. It's not that big a deal. I honestly don't see anything but very very marginal gains due to using a hotter plug, if any. Let's say you gain 1 HP from running hotter plugs rather than colder...is it worth your motor for 1 HP. It's not to me, and I have a spare engine sitting in my garage.

You will see just as much gains if not more at the track time wise by over inflating the tires or running less weight than running a hotter plug IMO.

 

Jime, Is C16 an aviation grade fuel? If not then who produces that? Also, is that fuel leaded? BTW...you shoud be fine with 100 to 105 pump octane, as long as you have enough injector and a big enough pump to push it. I think you got that covered though.

 

C16 is race fuel available at most tracks. There are several grades but this is the one most used for nitrous setups. It is leaded but I know of a few guys using it and have not hurt their O2 sensors or any other problems yet.

 

Cool
I know Bosch in the last few months has come out with some o2 sensors that can withstand moderate use of leaded fuel. How much remains to be seen?
What are your projections for your 1/4?

 

12.xx (fingers crossed).

 

You can do it and i'm sure the engine can take it without as much as a hicup too. High, mid's, LOOOOOOOOOOOW 12's ?

BTW, after walking on '00-'02 Camaro SS on the way home tonight I was a bit worried that something might be wrong with my engine. The reason I say this is it took me a bit more time to pull on the SS than I thought it should take. So I get home and it seems that at idle the engine 'might' have something wrong with it. It could just be my imagination, but I like to think i'm in pretty good tune with me car. Would you be so kind to tell me how to pull codes from the ecu. I know this is like beating a dead horse, but I've never bothered to pull codes before and would appreciate you assistance.
Thanks

 

Well I cheat now I have a reader, monitor etc.

The procedure to pull the code and reset is here.

http://www.vbxmaxima.8m.com/ecu.html

 

Thanks

 

Just went to pull the codes--nothing? Should I hear a clicking or ticking from the engine compartment? It is very faint but I can hear it none the less. Can a ECU be set up to not throw codes?

It is an aftermarket ECU from JWT and came in the car. So my ? is how or where might i find the OBD-II interface(msp?)? I also saw you say that you are running a S-AFC II and an OBD II data logger. Could you clarify the exact terminology for what s-afc stands for? I was under the assumtion that Apexi make the S-AFC I & II, and it can log and make adjustments. Am I way off here? If so could you educate a dummy please, thanks.

 

Not sure on the JWT it could be different. The OBD-II interface plug is in different spots depending on the year. My 97 is just to the left of the steering wheel under the dash its a white plug. My 95 is located on the passenger side right beside the ECU.

The S-AFC stands for Super Air Fuel Converter. It does only one thing besides display a few items like throttle position, battery voltage, etc etc. It takes the output of the MAF and modifies it before it reaches the ECU. It can increase or decrease the signal depending of whether you want to richen or lean out the air/fuel ratio. This is determined on the dyno, wideband O2 sensor, timing monitoring etc. The S-AFC does not log.

The OBD-II Scanner I have only displays, you cannot make any adjustments other than reset any fault codes. However it does display some very crucial info like ignition advance, coolant temp, intake air temp, o2 sensor readings, gas mileage, throttle position etc etc. It also allows logging of 4 different reading at once for as long as you want.

 

Is the interfacing plug about 1/2 inch thick and about 1&1/2 inches long? It looks like it will except the male end of an eight prong plug, could this be what i'm looking for?

P.S. Thanks for be so patient and helping me

 

Yup thats it, there are 10 pins that are used but some are blank.

You can buy cables very cheap but they are useless without the interface which is different for each manufacturer as well as the software. They are all hardware/software specific, believe me I tried to find a way around it by duplicating 2 different hardware/software setups.

 

Thanks bro

 

This may only apply to the new SAFC II, but this is from Apexi's website:
"The S-AFC is capable of monitoring and replaying the following data channels in Numerical, Analog Meter and Graph displays: Intake Manifold Vacuum/Boost Pressure, Air Flow Capacity, Intake Manifold Pressure, Karmann Frequency, Engine RPM, Throttle Position, and Air Flow Correction %"
-hype

 

Karmann Freq?

 

You don't really need to know about that since Nissan doesn't use Karman. Mistubishi is one of the few that do. Nissan uses Hotwire MAF just like Ford.