renix rebuild question

i recently rebuilt the motor in my 88 cherokee. I purchased a rebuild kit from clifford performance which came whith 264 h cam,60 over pistons.Ihad to have the block zero decked.I also purchased oversized valves and had the head ported and bored 60mm throttle body.now finally my question i am going to run 19lb ford injectors in it am i going to need an adjustable fuel pressure regulator?I ordered one from hesco just incase,but i would love to save the 240 bucks and put it towards a slip yoke kit if i could.any help with this would be greatly appreciated.thanks

I run the Ford 19lb injectors in my 88 with a stock fuel system with no ill effects.

i would but i would look into making my own or converting a universal fpr before paying hesco $240.

i would also experiment with larger injectors.

all that work, i would like to be able to fine tune the engine. hell, i would have stroked it for a little more.

what size injectors would you go with?the guys at cliffords dont run fuel injection,and when i spoke whith bennie at hescos he said if it wasnt stroked i wouldnt need bigger injectors,he said i should buy the regulator.i dont know anything other than what i research here and what the guys at the different shops tell me.i am at the mercy of everyone else.i just try to take in as much as i can and hope that what people are telling me is right!

The renix system is a pretty decent setup, so you should be fine. I personally would go with an aftermarket fuel system for a stroker, but thats me. If you were running something like 24lb injectors I would say go with an adj. FPR.

jcbsr1 said:

what size injectors would you go with?the guys at cliffords dont run fuel injection,and when i spoke whith bennie at hescos he said if it wasnt stroked i wouldnt need bigger injectors,he said i should buy the regulator.i dont know anything other than what i research here and what the guys at the different shops tell me.i am at the mercy of everyone else.i just try to take in as much as i can and hope that what people are telling me is right!

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question is, if you increase the fuel pressure, will it allow the injector to go over the 19lbs its rated for? are the ford injectors rated at 19lbs @39lbspsi(stock fuel pump pressure). i made the mistake at running accel 19lb injectors, but they are rated at 43.5lbs. my 89 runs great, but i have been looking into increasing fuel pressure.

jcbsr1 said:

what size injectors would you go with?the guys at cliffords dont run fuel injection,and when i spoke whith bennie at hescos he said if it wasnt stroked i wouldnt need bigger injectors,he said i should buy the regulator.i dont know anything other than what i research here and what the guys at the different shops tell me.i am at the mercy of everyone else.i just try to take in as much as i can and hope that what people are telling me is right!

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as a former parts salesman myself, Bennie is just tryin to make a buck off of you by saying you should buy the FPR. unless you were running turbo or a SC, the FPR wouldn't make a difference.

If you're worried about fuel delivery, get 21#/hr injectors (IIRC, injectors are rated at pounds of fuel delivery per hour, @ 80% duty cycle, @ a specified pressure. The pressure can be corrected for mathematically. I don't recall the equation offhand, but it can be found easily and is fairly simple - try Marren Fuel Injection, I think it's there. www.injector.com, I think. MSD may have it as well.)

The slight increase should allow the duty cycle of your injectors to adjust downward similarly (which helps the injectors and makes for more efficient fuel delivery,) and you can fine-tune fuel trim using an adjustable MAP sensor - which is cheaper to build and probably allows you more adjustability anyhow.

NB: It's useless to have the means to fine-tune fuel delivery without having the ability to monitor your exhaust! This means a "Wideband HEGO" (preferred) or an exhaust pyrometer (OK.) I believe Innovate Motorsports will have the better option of a Wideband HEGO, and this will allow you to see what effect your changes have. You'll probably need to weld another bung into your exhaust collector, but it's worth the trouble. Do that while you've got the exhaust out anyhow - any exhaust shop can do it for you, since HEGO sensors all use a standard thread (M18-1.5, they probably have a boxful of bungs and plugs. Get a plug when you get the bung welded in, and have the bung welded in just after the OEM and slightly off-angled, you don't want it directly in line. It needs its own sample of exhaust gas.)