minytrker

iTrader: (13)

I have to tune a a 408 that was built to run a lot of nitrous. They have 2 wet systems they are spraying. They want to spray a 150 shot on launch, then add a 250 shot as soon as possible and spray both the length of the track. Here is my plan, tell me how this sounds. I plan on tuning the motor, then tuning it with the 150 shot pulling 2 deg of timing and dialing in the a/f, then with the 250 shot only pulling 4 deg of timing and dial in the a/f. Once thats all dialed in then pull 2 more deg and spray the full 400 shot and the a/f should be straight. That should be around 20 deg of timing total and Im going to shoot for an a/f of 11.0-11.5. Is 8 deg enough for a 400 shot?

blacktransam

iTrader: (13)

i would try ti stay in the 18-20* range but i maythink about being a little richer than that.. i haven't had any experience with that big of a hit.. but i like to stay down in the 11.5 or below range with my 200 pop

Ray@Nitrous Outlet

For a 400 shot you are going to want to pull ~12* from the NA timing
4-6* retard for the 150 shot
6-10 for the 250 shot

11.5 would be our target a/f for the 400

Every car is a little different....so there is not a preset this is best answer.

Big Geek

iTrader: (2)

I would start with the total timing in the 12-14 degree range across the board while recording the AFR. It will probably be rich but so long as it is not popping you will be fine. Pay close attention to the logs and add two degrees of timing until you get around 11.0:1 then begin to add a degree at a time until you get your 11.5-11.7:1 AFR. At that point I would go through the entire graph and see where you should be adding a few more degrees at in the lower PRM range until you get your AFR where you want it. Up to the 250-hp setting you should be fine with up to 20 degrees of total lead so long as your octane and fuel quantity are straight. I will warn you though with that big of a shot (400-hp) you don't get to many chances to correct a lean boo-boo before you are picking up pieces. Take your time, err on the side of caution and make as many pulls or passes as it takes to do it right. Good luck slim.

Jim C.

minytrker

iTrader: (13)

The next thing is the fuel system on here. It has a differnt pump a 255 something, stock rails and 42lb injectors. That seems like a lot for a stock fuel rail.

ls2formula

iTrader: (7)

Are you says that adding timing will lean it out some?

V6 Bird

iTrader: (15)

you seem real concerned about timing etc...What about the plugs to light this big shot...

Id run a NGk r5671a-10!!!! gapped at .023

V6 Bird

iTrader: (15)

That motor will boom with that setup on 400 from both systems...They need their own fuel supply for sure. 150 would be fine off the fuel rails but the 250 or even both really need a standalone setup.

juicedimpss

yes it will.

98redorangeta

iTrader: (10)

I would think that your tuning job would be a littler easier if you had a dedicated fuel cell with some race gas in it.

srsnow

If you tune both kits sepratley you may need to go back and lean the second stage out. When you add a second stage that will be run with a first a lot of times the second kit will run a little rich. Giving each stage its own bottle will help with this some.

ls1408cp

iTrader: (37)

now lets say he had a dedicated fuel system for the car and ran c-16 in it would he still pull that much timing? I didnt see anyone say about what gas to run and how it affects timing or does it?

srsnow

On C16 I would pull out about 3 per 100hp

juicedimpss

imo the c-16 in the dedicated system is just a safety net.I wouldnt lean on it more just because there is good fuel in it.close on the tune vs on the ragged edge is not a big difference in et.

import slayer

I have a 4400 stall and I will be spraying a 100 shot. What rpms should I set my window switch to ?

blackls6

minytrker

iTrader: (13)

Thanks for all the help. Desided to go to dedicated fuel sysytem instead of chancing it.

V6 Bird

iTrader: (15)

3000rpms

import slayer

oooops !!!I did not mean to post that here sorry

3stgstocker

iTrader: (18)

so how much do i have a 93 jet in single small solinoid and a small single noid teed into 2 lines with a 28 and a 63 all in the air box. aka. worlds fastest stock camaro what kind of shot is this i got all on stock fuel system?