SRTKLLR

iTrader: (1)

I have a low cr(9:1) 408 in my Silverado and want to know how much I can safely spray and what my timing should be.

It has the following.
9:1 compression
AFR 225's
224/231 .595/.595 114

I started with a 50 shot and quickly moved to a 100. I recently went to a 150 but I think I am at the limit of the stock fuel pump. I will be getting a dual pump kit from Lonnie's but it is mostly for the turbos going in.

In the meantime how much can I safely spray on pump 91 California gas? Being that it is a low cr engine do I still have to pull 2* per 50 of timing?

I can run 109 or C16 but I want to see how much I can run with pump gas so when I am on the street I know if I can flip the switch or not.

custm2500

iTrader: (11)

If you are on a stock pump I got to imagine that the 150 is pushing the limits.

The best way to start, is conservative, pull 4-6 for the 150 shot. See how everything is going and add timing if you can. Especialy since you are running a 408 there isn't much if any data on your set up so you need take safe baby steps and build it into the beast it will become.

Graham@NitrousOutlet

I would pull 7-8* on the 150. But I would not spray any more than you are on the stock pump with a 408.

What does the tune look like now tho? Is it an NA tune for the 91?

If you do not now the answer to some of the questions you ask ( Not a knock, Its a good thing you asked here ) you definitely need to take it slow. Also if you have a tuner, keep him involved in this. I am sure he has more knowledge on the combo and your driving habits.

SRTKLLR

iTrader: (1)

I started with a 50 shot and pulling 2* then moved up to a 100 shot and pulling 4* then wen up to a 150 and pulling 6*. I have not been able to get a full run in on the 150 first because of an electrical problem(now fixed) and then because I was out of nitrous(I think I have a small leak) and because I have the NANO the pressure is still 1050 but it was just spraying air with a heck of a lot of fuel.

I switch tunes when I want to spray and my timing is about 23* NA then I have been taking away 2(50 shot), 4(100 shot) and 6(150). For the track I splash a little 109 in the tank but I want to make sure it is safe without it. That is just for peace of mind at the track since it has been really hot and I am hammering it and hot lapping it a lot.

BLK02WS6

iTrader: (2)

If that 408 is makin any kind of power, it should be using up the stock fuel pump by itself... I wouldn't be spraying nothin on a 408 with a stock fuel pump!