1991MJPioneer

Well first things first I've gotta test the flow rate of my pump. I definitely don't have the money to buy a pressure regulator or a pump or get injectors cleaned. I'm a poor college student so things will get fixed as I slowly accumulate the money :cheers: Theres a book called Jeep 4X4 Performance Handbook that has those formula's in it. I've seen them too on Jeep Strokers forum. Thank you Don :thumbsup:

My apologies - didn't notice you had a 4.5 stroker. :D I'm using the 96-99 Mopar 23.2lb/hr grey tops, p/n 53030778, and running them at 46psi. These provided the best numbers on the Hesco dyno for my particular setup w. the cam, exhaust/intake mods and Unichip I have. If you frequent the stroker forum or the Hesco forum, there are long discussions regarding optimum stroker injector sizing. Most, but not all, if using the Ford 24# injectors, end up running them at a lower pressure than the stock regulator lets them. You might get by using them on your setup, but only a dyno run (not the olde butt dyno) will let you optimize it. HTH......... No problem Don. :cheers: I actually have two sets of the 96-99 grey tops. I bought a 97 block and the guy just gave me two intakes with everything...unfortuneately I don't know what condition they are in. I guess you're running the Hesco Adjustable FPR? and I suppose the guys running the Ford 24# end up with too much fuel if running at stock pressure? is that the later 50 PSI pump or the earlier 39 PSI H.O. pump? Will the factory 21# injectors suffice for now or should I invest my money in a FPR and different injectors?

Ok cool. I'll read up on it tonight. What size injectors are you running in your stroker Don? I've read that guys have used the 24# Ford in strokers. Also my concern was that with my stroker, I'll have detonation issues because I'm running a stock cam and 9.7 to 1 compression. I was thinking that the larger injectors might be beneficial.

Darn...well. I'll get on that flow rate test then. I was considering replacing the injectors with higher flow units anyways at some point. I suppose I could buy new or cleaned up ford 24# injectors somewhere. I'll aslo see if the '91 FSM has anything on testing for flow rate.

Ok. Good news. I have fuel pressure finally and the engine idles. I set the pump in a bucket of fresh gas and pumped directly to the rail bypassing the old fuel filter. It took a good few times to prime the system and for it to hold pressure, but it shows me about 35-37 PSI while running. As of right now, the pump is holding at about 30 PSI with engine off. It might still be dropping as thats what it was doing. I would hope this means that I have a useable pump. The engine cuts out if I attempt to rev it. I suppose this is because the oxygen sensor and coolant temp sensor arent hooked up and it is in open loop. Right? Thanks for the help ;)

Just wanted to know if the pump strainer could've fallen into the tank. It wasnt there when I removed the pump. Thought I'd ask here tho since I'm kind of a noob when it comes to some stuff. ;)

How do you expect it to run if you don't have the engine control sensors connected? :smart: :rotfl2: Yeah I know it won't run all too well without all sensors hooked up. I know the engine fires...I'm not worried about it running perfect right now. I just am trying to figure out the fuel pump issue so I can have fuel pressure. :???:

you said you replaced an o-ring at the fuel rail, any way you accidently got something inthere an plugged it up? like the old o-ring perhaps? Doubt it. I threw the old o-ring away. I had the no pressure problem the first time I tried starting the truck.

So today I took the fuel pump/sender unit out of the tank and to my suprise....there was no strainer sock on the fuel pump... :dunno: I tried looking down in the tank and it looked relatively clean for a 20 year old truck...but couldnt see if the strainer had fallen off somehow. Could the strainer possibly fallen off in the process or removing the pump? I tested the pump briefly while it was out of the truck and it pumps...but I don't know the proper procedure for testing it Anybody?

Yep definitely no fuel pressure at all. I checked with gauge. Also depressed valve on rail with screwdriver and it just hisses and bubbles. I disconnected fuel return line and a little fuel came out but not much. I poured a little fuel into the intake and it fires right away. I haven't checked the timing again yet...but I thought I'd start with the fuel problem. I'm gonna take the fuel pump out and check everything.

Actually... :roll: yeah the fuel in the tank is from last June. I just wanted to see it start and then I was gonna put fresh gas in it afterwards if everything worked. I did a check at the test valve and it showed me nothing yesterday but I'll mess with it again. I'm not 100% positive that the dist is set properly, I thought I set it properly before I put the motor in. As for the dist...it may be one tooth off...its pointing in the right direction and its set at number one end of compression stroke. :hmm:

Well I tried starting my stroker tonight... It seems that everything is functioning but I'm just not getting good fuel pressure to the fuel rail. Fuel pump is working and is pumping fuel. It is noisy though. It was just as noisy as when it ran last summer. Tonight when I cranked it over, it fired a few times and then started spraying fuel from the pressure regulator on the fuel rail. I went to the parts store and bought a new o ring...it stopped leaking, but now its not firing at all. Good spark as far as I can tell. Engine malfunction lamp is blinking also... Could my problem be partially because I don't have the oxygen sensor hooked up along with the coolant temp sensors? I don't really know where to start. Could my fuel strainer sock be plugged up? the truck has been sitting since last June.

Yeah H.O. Looks like this...

Sorry. The teeth for the CPS arent on my 91 flywheel, Instead, they are smooth.

I know that the flywheel on my 91 H.O. does not have the upper notches. They are smooth. So my guess would be that it is a Renix.