Ok I just installed my 383 with Vortec heads SDPC intake forged internals, yadda, yadda, yadda. I have a few problems.
1) I have a new Milodon pan and my y pipe won't fit. I am gonna have a custom one bent or true duals made not sure yet.
2) I have two injectors which are bigger than the rest because the last owner only replaced the two faulty one's and made them bigger units
3) I would fix these problems, but the idle is loping really badly beteewn like 400 Rpm and almost dying then up to around 1,200 RPM. I am trying to set the timing but I can't because of this jumpy idle. If I hold the throttle linkage part way open I can get it to idle at like 1,000 but that is the lowest idle it will hold.
4) I am not a hillbilly about the injector sizes but I am a poor colege student who has begged, borrowed and stole pretty much every scent I can and I need to at least fix the idle so I can work on my other problems. Where I need the advice is my plan of action.
I am going to go through the whole system and make sure I do not have a vacuum leak. Then I plan to disassemble my IAC, clean it, and reset it. Then I am going to check my TPS voltage and make sure it is good. If my problem is not solved by then I will replcae the IAC valve. Does this sound like a good way to go? I can then get my exhaust fixed, buy new injectors, and start to burn the correct chip for them. Just looking for some advice on my plan. Thanks guys

 

Steal one more time or sell your left leg or something, but get the right injectors!

You tell us, will your y-pipe fit or not?

If you can't get it to fit it doesn't fit, get a new one. (I dont recommend SLP)

All you need is for the engine to crank to set timing, just use 2 people.

 

Without an AFPR what size injectors should I get? I don't have an AFPR yet and I don't have chip burning supplies either. I know I need an injector upgrade but I at least want to get the car to idle first so I can time it and then buy injectors. This Y pipe is definately not fitting so I am gonna try to go with true duals.

 

Also does my troubleshooting of the lopey idle sound like the correct way to go

 

I wouldn't even RUN the car without 8 matching injectors.


I'd say somewhere around 26-28lb/hr depending on prom tuning/AFPR/HP

 

So I could get some accel 28# per hours and install them in the car but would it run on stock fuel pressure. If it would then this will be my first course of action. Then I could get the idle fixed, set the timing, fix the exhaust and finally start burning some chips. Thanks for all the help

 

no problem...

but be warned 28's WILL run rich period untill you get a prom burnt for them.

 

What Milodon pan are you running. I run the 7qt, and my edelbrock y-pipe was too large. Unfortunately I had to get the pipe that runs from the drivers side to the passenger side reduced to 2.25 in order for it to fit. Eventually I will swap the pan for Milodons 6 qt so I can run the larger y-pipe again but I'm in no hurry to pull my pan.

 

Yeah I have the Milodon 7 quart too. I was gonna get my y pipe modified but I still have the stock cat back and I am gonna replace that later too. So I figure that the price difference between a modified y pipe + new cat back might not be too far off of getting true duals. ROC getting the new injectors would make me run rich but will the car be driveable? If so the new injectors will definately be my first step. Thanks

 

as long as they are not too far oversized(i am sure one of the other guys here is far more up on injector ratings and such and will correct if i am wrong) the computer can compensate enogh to make the car run. I am running 24# SVO injectors(have been tuning my prom, thanks to Craig Moates software and ZIF chips!) and the car ran ok/smooth idle. With the prom tuning i have done so far, the car runs even better. In other words, as long as you don't step way out on injector size you will be ok.