Jeep Strokers

So here is my recipe. It's currently at the machine shop.

91 H.O. Block and head
12ctwt crank
4.0 rods
kb944 pistons 30 over

Ill be using the standard cam that comes in a normal rebuild kit

What injectors am I looking at?

I currently have the bosch "703"'s
They were in my engine before and when I took it apart it was running lean in 3 cylinders (white buildup)
Do I reuse them (after cleaning and testing)and get a map sensor adjuster and go +5v?
Or do I jump on the 24 lb hour mustangs on ebay right now?

also, anyone know/done this recipe and know the hp/torque numbers?

I dont have an intake or exhaust (magnaflow muffler tho)

The 703s might work for you. Someone else here is running them. Looking at the cylinders and spark plugs isn't a good indication of how well sized the injectors are for your engine. Under most circumstances the engine will be running lean with a AFR of 14.7:1.

So I shouldn't be worried about the whiteness on my head and in my exhaust pipe? I will eventually get a a/f gauge and better injectors but I guess the 703's will work with a computer reflash?

The 703's also known as "Neon" injectors as that's the most common donor vehicle will run, the only issue is that they may be unable to keep up in a WOT situation. I have them in my ZJ with a 4.6 and a WB O2 shows good mixture throughout the closed loop mode of operation, that is until WOT, then they are unable to keep up. For ME that isn't a problem right now as I'm tranny limited (it really needs a rebuild) I can only really open the throttle in 3rd gear with OD disabled, any other gear I will break the clutches loose.

Just my observation, your mileage may vary(pun intended :})

Hey thats all I needed to hear. I wont be opening it up anytime soon, So Ill wait till that time is close to order them.
So do you have any map sensor adjustments or Fuel Press Reg to help, or are you just strictly on ECU and 703's?

I'm running a stock 96 ZJ fuel pump with 49 PSI, I tried playing with adjusting the MAP sensor voltage, but wound up with it's being right at 5.0 volts so I removed it. I do live at about 5400' above sea level an altitude does play into what the MAP sensor puts out. I do also have a set of the Ford Racing blue top injectors, but during some trouble shooting they got swapped out to the 703's, I just haven't found the need to swap back yet. I'm sure I will once I get done with the trans.

Im currently running "703's" aka Bosch 280155703's in my 4.7 Stroker. I do have an Adjustable FPR and Adjustable MAP. The switch on my MAP is off so im running stock voltage to the MAP which is 5.06v.
Adjustable FPR is adjusted down a bit, but im not sure what exact PSI as i havent checked it since i adjusted. I know these injectors flow 23#hr @ 43.5 PSI (21.8#hr @ Stock 39PSI). My AFR's are 14.7 at idle and part load, anything over 75% throttle drops me to 13.5ish. If i pounce on it, i drop to around 13.2, and by the time i redline AFR is around 12.

Here is my build thread:

http://www.jeepstrokers.com/forum/viewt ... f=8&t=2317

Jor2010dan wrote:So here is my recipe. It's currently at the machine shop.

91 H.O. Block and head
12ctwt crank
4.0 rods
kb944 pistons 30 over

Ill be using the standard cam that comes in a normal rebuild kit

What injectors am I looking at?

also, anyone know/done this recipe and know the hp/torque numbers?

I dont have an intake or exhaust (magnaflow muffler tho)

The modified "poor man's" stroker is becoming increasingly popular due to its simplicity. HP/TQ numbers will depend on whether you've ported the head and what other performance-adding bolt-ons you have.
For '96-'04 OBD II Jeeps the Accel 24lb injectors coupled with EV1 to EV6 injector harness adapters work very well. Flow is 25.7lb/hr at 49psi.

Hey Maud. you are actually running rich at WOT with the 703's? Or do you run lean?

As i stated in my original reply; i start out a little lean at 13.5-13.2ish and then by the time i hit redline i am rich down to about 12. Thats the best i have been able to tune and adjust with my RENIX... all using the Adjustable FPR.

Oh. I thought that 14.7 was ideal 14.7-20 was lean and anything below 14.7 was rich. so I'm thinking maybe your 13.x is rich? I mean all I can find says that

Under WOT, you'll want a NA engine to run an AFR near 13.0:1 across the whole rev range. That's a difficult task to achieve without expensive custom PCM programming so most of us try to get close using cheaper methods (MAP adjuster, AFPR) with mixed success. Even then you might find that with the stock PCM program (except '00+), the engine can run an AFR near 14.0:1 at low rpm and gradually enrich with rpm, dropping to 12.0:1 or less at the redline, so it becomes a compromise.