Isn't 20 degrees of timing alot for a 300-350 shot?

 

Nice runs Devon, was fun watching you pull the wheels. One of these days I'll post the video of the 9.49 run

 

its alot with 93 octain!

 

I was actually wonderin about the injectors myself, but the dry isn't puttin down that much power, the .51 jet only put 70 to the wheels and the motor on the nitrous tune puts about 42x to the wheels, so I don't think i'd be over doin it on svo 30's which are like what, 36's on our cars? So i'm probably lucky if i'm gettin 100 - 110 to the wheels out of the .62 jet.

If I ran a higher octane in the tank, it'd have to be 104, don't wanna kill the o2's, still runnin off the o2's, haven't done an open loop or speed density or anything like that yet cuz I still haven't picked up a wideband.

 

yhea, id say go bigger injectors, and bump up to 104 in the tank, and 117 in the cell when you mix them you will probably be around 108 total or so.
try that and see.

 

Thanks dude, and that would be awesome, wanna see the vid again!!!

 

I'll take a look, thanks Steve.

 

i wanna see the vid

 

No, how do I check the duty cycle, can I do it with autotap?

 

Yeah, everyone said it actually spun on the 9.49 run, the second run would've been better cuz she dead hooked nasty, but I had to let out cuz I started goin toward the wall, either lined up crooked or got out of the groove or something.

 

I would bump up the injectors. I am at 125% NA on the 28s from GM and I am cam only. 30s would probably do for me but I want to go bigger for future plans. You should look into the 42s as well. They flow like 50 on our cars.

 

I'm not sure with auto tap or i have never used it i use efilive

 

i agree, any car i do that makes over 400 on motor gets 42's. id rather have to much and tune around it, then not enoph.
i run 42's on my car, and make a little over 450 motor wise and 2 stage wet.

 

Devon -

Maybe I missed it, but what is your total shot size. What's the car run on motor then? Just kinda wondering

 

20 degrees total timming is to much timming for a 300 shot.....
Dave

 

Here is the math for injector sizing, a general base to go by. (this is only good for V8 engines)
Projected hp (crank) x .55 (BSFC) / 6.4 (com denom) = min injector to meet 80% duty cycle

I used your middle ground suspected rwhp from n/a and dry= 525rwhp
Now, I take and add 15% drivtrain loss to get BHP (crank)=603.75bhp

So,
604 x .55 = 332
332 / 6.4 =51.90lb min injector to meet 80% rule

We can see just using your suspected hp middle ground that your pushing the injectors pretty far, and if your off on hp it may be worse.

Here is the math to figure your bhp your 36lb (at our pressure) injectors can safely support.
Known inject size x 6.4 / .55 = hp supported considering the 80% rule

So,
36 x 6.4 = 230.4
230.4 / .55 = 418.9bhp/481.7rwhp safely supported with your injectors.

Once again, shows you are worse than border line or past the safety rule.



Now on the back fire, here's my take. Beause your injectors are border line, I believe that going a tad lean caused your plug to melt (along with a couple other things, octane and timing). Then once the plug debri was flaoting around, a piece was caught in the valve and allowed that clyinder to fire out of sync cause valve was stuck open. That's where the back fire came from, imo.

I run two bottles in my car because I hate the pressure going down during the day, and I am lazy, dual 15lb'ers. Congrats on a new best, you deserve it after putting in all the hard work.
Robert

 

Well, they claim the .62 jet is 150, but it doesn't put down anywhere near that, so I guess you could say 350 shot goin by what the dry pill is supposed to be, was on a 300 with the .51 jet, but that jet only put down like 70. She's gone a best of 10.95 @ 124.41 on motor in good air, in this same air I just ran in, she'll go 11.2's - 11.3's @ like 122 - 123.

 

What would you recommend?

 

Thanks dude! And that formula is pretty cool, but can I ask a quick question, how is bhp lower than rwhp, I always thought it was the other way around, but maybe i'm just not understanding the formula.

 

Also, one other thing, not sure if I mentioned it or not, i'm running #7 plugs, I would go to 8's, but I do still like to drive the car around on the street and as it is I have to get on it to blow the plugs out if I cruise around at low rpm too long. Of course I always put fresh plugs in before I go racing, but i've heard the 8's will foul out like instantly.