NosLaser

I have an essentially stock '01 Z, and just ordered a nitrous outlet plate kit which I plan on spraying 100 shot with.

The car has a vararam intake, an x pipe, a centerforce DFX clutch, and the preloaded Diablosport intune. I'm assuming the Diablosport intune has bumped up timing above baseline. It has adjustable parameters for timing (that I obviously haven't touched yet) but for 100 shot, do you think it would be a fair starting point to pull maybe 2 degrees out across the rpm range, read the plugs, and then go from there?

Ideally, I'll want to get a dyno tune of course with the ability to switch between my NA and nitrous tunes, but I don't want to do that until I do LT's and a cam so I only have to spend the money once.

I figure enough people have real world experience and can point me in the right direction.

JoeyG

You can add a cheap timing retard via IAT switch mod, so nitrous is activated and computer thinks inlet temperature is much higher than actual, and pulls timing. Several vendors have nice preset up kits to do this also. Or you can get an actual tune that will more than likely improve the generic handheld canned tune you have and verify the nitrous hit is safe timing/fuel wise.

Shoaf85

IAT trick will work or ECT sensor as well. He will need access to those tables though via a custom tune to set them up for the correct amount of timing retard.
Joey you are experiencd enough to be able to tune your own car, makes these type of things so much easier

NosLaser

Thanks for the replies. In the meantime while I'm deciding which way to go (I'll have to research exactly how to set up the IAT mod so I know how much timing it's pulling) do you think just going into the tables on the Intune and retarding timing a few degrees is a viable option prior to a more permanent option?

Essentially I can drive the car on the loaded tune for now, and when I go to the track and run it on nitrous, I could go into the tables and pull maybe 2-3 degrees out...I was just wondering on a Corvette-specific application on 100 shot if that sounded like a pretty close starting point.

C5 Pete

If you have the ability with your handheld tuner to pull a set amount of timing while at the track, I'd think that should work fine.
One (two?) question though. Do you know exactly how much total timing is in it from your handheld? And will you know exactly how much timing is in it when spraying the nitrous?

Anthraxmm

2°/50hp is a general rule. I'd start with at least 4° pulled, you can always add it back in, but you can't pull it back out if it's to late.

NosLaser

Yessir I have that ability, and I could datalog with the handheld as well to see exactly what the total timing is. Does anyone know approximately how much total timing the stock tune on a C5Z is supposed to run? (I know it can vary with temp, air quality, octane, etc but just an overall average.) That will give me an idea of how much timing this tune is adding in the first place, so I may need to retard it back even further to coincide with what a stock tune would run (if that makes sense.)

That is a very valid point.

JoeyG

I think a stock ZO6 is around 23-24 degrees advance from 4k rpms up. Generally speaking most cars on engine alone live happily and healthy at 28 degrees in that 4k and up category. Log your car and see what it does from 2800 and up. Then you've got a starting point. In some different setups through the years ive always been in the 22-23 degree range from 2800-4000 and the 24 degrees at 4000 for a safe tune. BUT you need to verify the fuel is correct because lower timing at lean AFR runs great until a piston goes.

Chris Stewart

I sprayed 100 on my stock Z and didn't pull any timing. Run good fuel and it should be fine.

Chris Stewart

Oops I missed the Diablo tuner part. I dug up my stock tune and it has 22 degrees from 4000 rpm up.

NosLaser

Thank you very much for the replies and the insight. I'll do some logs and see where it is at so far, and then shoot for a safe amount of retard and then adjust from there. I can log air/fuel as well...looking for maybe mid 11's:1 on the spray? 11:5-11:7? While I'm in there, a set of TR6 plugs gapped around .035 seem like a good starting point as well? Thanks again.

JoeyG

That should work well, I always try for 11.75-11.9 but lower is safer. Keep the updates coming.

mattressbouncer

Go with the BR7ef plugs instead.

TXGS507

This,..... Gap'd @ 29...

Chris Stewart

BR7's are a pretty cold plug. Seems to be popular lately, but doesn't make sense to me. I run TR6 to 900rwhp then switch to 7's when I push for 1000. Running those plugs on a stock motor with 100 shot seems a bit much.

Anthraxmm

The br7 is a non projected tip spark plug where there tr6 is not. For nitrous use a non projected tip is a safer plug. Also a br7 will run just fine off nitrous.

John_B

What are you guys doing for fuel on a 100-150 shot? Just injectors? Do you need a pump? And running 93?

ssrallyred

I am running a NX plate kit and BR7's on a hundred shot on my NA tune (390/370) and all is good. I will add a booster pump before going 150 or more.

NosLaser

You had me at non-projected. Looks like BR7's it is.

And I'm a *****. If these cars seem to run okay on just 100 shot on the stock tune/timing, it would take the exact same amount of time to just upload the stock tune into the car for when I want to run on spray as it would to go in and adjust parameters on the canned tune. I may even upload the stock tune and pull like 2 degrees out just to be safe as a starting point, read the air fuel, read the plugs, and maybe go from there.

NosLaser

I apologize in advance for this silly question.

I don't know if this is unique to the Diablosport inTune, but every time you make a change to the tune, the car goes through this lengthy relearn procedure; i.e. if I want to pull timing at the track, the car will run like **** for about 150 miles since the pcm is reset during that process.

Are there any tuners out there that will allow you to switch between a 'motor' and a 'nitrous' tune instantly without this relearn procedure? HP Tuners?