I have an 86 svo completely stock for now. Just have the stinger 3 inch downpipe and the xhaust from stinger. Bought a front mount and turbo manifold from gnari. Also bought a turbo that's a t3/t4 hybrid. Boost controller from Stinger. Fuel pump and fuel pressure regulator. Etc. And a port and polished head. With a boport cam. I'm not planning to go crazy. Need advice on if I can stay with the stock injectors and computer. Have the PE computer and 36 lb injectors. Please email me if possible at katehisevangelos@gmail.com
I think you can stay with the PE and stock injectors, but I wouldn't push them beyond 13psi of boost without datalogging a wideband signal.
I want to pump at least 18 lbs.? Or I heard even 20-22lbs is safe. But what do I know? I want to get at least 275ish and I've been told that's possible with the stock computer and injectors.
17-20# is safe on a stock head, but with a T4 compressor and ported head, you might go lean with that boost. It's hard to say. That's why I mentioned a wideband and a way to datalog to see what is going on before turning up the boost.
02-02-2020, 03:46 PM
(This post was last modified: 02-02-2020, 11:22 PM by
Howard.)
I started modifying my 1986 SVO basically the same way...You need to understand there WILL be tradeoffs!
First, you need to understand HOW the "PE" computer works. The way it was explained to me, is that Ford designed it based upon WOT fuel needs, then removes a programmed amount of fuel for less throttle input. This works great in a stock arrangement, but causes issues as you modify it.
Changing injectors to get more HP is difficult with the PE/stock VAM setup, but you CAN "lie" to it, making the injectors effectively bigger. This can be done by using an adjustable fuel pressure regulator. The stock regulator is set at around 39 PSI base. If you use an adjustable regulator, you can bump the pressure to 43-46. THIS REQUIRES A WIDEBAND TO HELP YOU KEEP THE AFR CORRECT!!!!! This will push more fuel into the engine, to keep from leaning out under high boost conditions, but at a cost. Remember how the computer works! If stock it pulls out "X" amount of fuel from WOT fuel, it will pull that same amount from the higher pressure fuel. This will create a rich condition when you are off WOT. In my case, my mileage dropped from 22 to 17 MPG. Only you can decide if that tradeoff is worth it.
I am sure those with more knowledge can give you better advice, but this is my understanding. After 6 months of 15-17 MPG, I spent the money on a PiMP, which is a MUCH better computer w/more options than the Ford PE. For example, it can shut off the injectors entirely under high vacuum/no throttle (going downhill) this can pick up 2-4 MPG.
Good luck!
1986 SVO daily driver. PiMP v1.4/3" Stinger exhaust/FMIC/Schlodes Manifolds/Boport 2.1 and head/GM 3700 stall 200-4R auto trans
1963 2.3T Ranchero Project
The max stock power without "messing" with things like fuel pressure and having a wideband and such is closer to 235hp than 275hp. 275hp on all stock controls is about at the max range when you know these engines like the back of your hand, know how to optimize everything to the edge of destruction, etc.
It really comes down to whether you're OK being limited to whatever the stock ECU and injectors will give you, or if you don't want to be limited by that stuff and would rather be able to maximize the parts you've already bought for it (and not have a hard cap on what you can do beyond that).
Please just buy a Pimp when you’re able, so you don’t end up on jackstands! Lol! Seriously a Pimp will make even a stock motor run better and smoother, not to mention it’ll allow you to control and tune for virtually any modification you chose to do.
2017 F150 Ecoboost 3.5 TT (sold)
2017 Mustang GT PP (sold)
2019 Mustang EcoBoost (sold)
86 SVO not stock
83 Ford Ranger project
2019 E350 service body, work truck and tow rig.