Pro Stock John

iTrader: (34)

Wow that's awesome.

Forced370GTO

my rc 75lb injectors were at 93% duty cycle at 717rwhp (mustang dyno) with a boost referenced regualtor on a race fuel setup putting 70psi base pressure to the rails... that was at 13 psi on a 403. if your going to spend the money, go with the versa fueller and some low impedence 96s

alwaysinboost

I'm running 96# injectors with two fuel pumps & no meth with an F1. A/F is good on pump gas.

kp

iTrader: (34)

Congrats on the numbers, but you are playing with fire with those injectors. I have low impedence 75lb injectors @ 70psi and I am at 95% with the F1A @ 20psi of boost. Dont waste your money on the RC 75s, do a converter and 83s or 96s. FWIW with the F1A @ 20psi I made 740rwhp with the TH400 on a dynojet (I dont like posting dyno numbers with the TH400 because they dont look 'cool' compared to the dyno big hitters lol), you are making some great power but be careful.

eb02z06

iTrader: (18)

Your 100% right Kp. I figured the 60's would be okay-what I didn't factor in is that my factory regulator only went up to 60psi. I need to get a aftermarket regulator with a boost reference of 1.1 to it will go from 55 to 75 psi under boost. I had really back luck with the injector driver back in my mustang days. My duty cycle at the top of the run was 130%-but with the meth and boost referenced regulator I think I'm pretty sure i can get it down to 90% the fuel was 10.8 through most of the run and at 5800 it would climb up to 11.1 then 11.5. My pe table goes like 1.1, 1.2 then 2.1 at 6000-that's when my pressure dropped to 45psi-the injecotrs go fully open! Then again this is a dyno and don't mean squat until I get it to the track. Is there a problem with the RC75's? Most of the Vette guys making over 800 rwhp are using them successfully?

qqwqeqwrqwqtq

Nope, other way around. You're pe table jumps because you're trying to compensate for the fuel pressure dropping.

kp

iTrader: (34)

I ran the RC 75s and they didnt do much better then the 60s really. The meth makes up the difference but if quits in the middle of a pass you are screwed with that duty cycle. Most pumps wont sustain 70psi so you are really better off with the larger low impedence injectors. The 'new' style versa fueler works pretty well, not perfect but works. I fought with the fueling all last year and finally gave in and did a real fuel system, its a never ending cycle lol.

What kind of boost numbers were you seeing and what is your crank pulley diameter?

motorbuilt

iTrader: (17)

Ive got 1000cc RC injectors (96lb), they have no issue with that horsepower level at 59psi....they have nice street manners for driveability, i'd recommend just doing it right the first time to make room for future horsepower increases.

(only down side, they were like $7-800 bucks.., I run BS3 to control them)

eb02z06

iTrader: (18)

Motorbuilt-you have the YSi right? Did you get your issue sorted out? The 1000-are they low impedance? Kp-what about the AEM driver? So what is the best most tunable low-impedance injector?

kp

iTrader: (34)

I had not so good luck with the AEM, spend the extra 100 on the versa fueler..

Opinions will vary on the injectors, I would ask in the fueling section who is having the best luck with which specefic injector.

mikes99corvette

iTrader: (5)

I dont think is the injectors, I think Arun is having the same problem I had on my 383 D1SC, My problem was fuel pressure. Arnold finally installed a switch that only activates the external pump when the car goues under Boost.......Now its running like a champ!

FactoryRaceCar

Awesome job bro. Dave does great work. One day I will have a forged short block by him

eb02z06

iTrader: (18)

I just talked to Lonnie from LPA and he's going to see if he can build me a custom dual pump intank setup. I'll also get an aftermarket regulator with a 1.1 boost rerferenced setup and see if the fuel pressure at least stays up top.

alwaysinboost

it will be interesting to see your track times. we have essentially the same setup except your cars an auto. I have a feeling 9's won't be a problem for you.

eb02z06

iTrader: (18)

That's the plan bro! Bro-didn't you say that you used 96lb injectors? Are you using a injector driver? If so which box?

eb02z06

iTrader: (18)

Kp-what size injector are you running bro? I may just have to go BS3 and call it a day-lol!

kp

iTrader: (34)

I am using 75s right now (dephi low-z) but I can hold 70psi of fuel pressure easy. I have 83s but I just havent put them in, car is running where I want it so no need really.

If you go BS3 you will lose your ETC I believe and then your traction control/anti lock doesnt work either. Maybe someone worked a way around it nowadays though, I dont pay much attention to C5 stuff. I would defiantely do a dual fuel pump and front mounted regulator, one of the C5s that Bob at EPP posted about a while back had a pretty stout fuel system from ECS I think that looked pretty good.

It really depends on what your goals are though, you are probbaly making enough power right now to break rear diffs fairly easy if you race it a lot and you are looking at the safety stuff if you want to run 9s at any bigger event. The 60s + meth and a dual intank setup will probably do you OK for mid 9s. I ran mid 9s with 60lb injectors, dual walbros, -8 feed line and a front mounted regulator on race gas alone so you should be OK with that IF thats all you are looking for. If you want to go faster reliably whip out the big checkbook because it comes in waves lol.

eb02z06

iTrader: (18)

I hear yah brother! I'm using you as my role model man-what you've done is awesome. First and foremost the car must remain streetable. So saying that I'm going to take baby steps-the dual intanks, and a front mounted regulator and lets see what happens with the meth. If that still doesn't do it then the versa fueler and some 83's. oher than that-I'm done-it's not worth making anymore power for a DD with this chasis.

kp

iTrader: (34)

IMO its not worth it tearing up a nice Z06 for a drag car, rob133 or something like that on corvetteforum ran a 6.08 in the 1/8 with his C5 vert (346/D1SC) at the Pinks thing I was at (blew a pipe off and didnt make a full pass) and I think he broke the diff last week. He got it to 60 foot great but now the weak links start showing up.

I honestly liked my car a lot better when it ran 9.70-10.00s and it had a 6pt roll bar, comfy seats, intank pumps and I could drive it anywhere, I hate driving the car now with the cage, all the rod end suspension stuff rattling away, seats that are as comfortable as a mcdonalds booth and the fuel pump that sounds like a bad electric toothbrush.

But its hard to resist trying to go JUST a couple tenths faster lol, I'm sure the car will exceed your ET expectations if you get it to hook.

motorbuilt

iTrader: (17)

Wrong guy.... Turbo 403" ls1 in a mustang.

Yea low imp injectors...