Once again guages are what will save the engine when you add more power. The transmission is the expensive weak link in these trucks and since you tow that trans temp guage will confirm that you more than likely need some additional trans cooling.
The open air intake will accomplish 2 things 1 allow the engine to breathe better and prevent possible sealing problems with the stock air box, these sealing problems were quite frequent and easy to happen especially if your airbox hasn't been updated to the metal hold down bolts.
The FPR (fuel pressure regulator) shimming increases the fuel pressure to what the pressure that ford used for the california splitshot trucks that ran a mechanical fuel pump. The downside to this mod is that most of the guys who have done it on higher mileage trucks have reported that shortly after they had a failure of the fuel pump. I know mine began leaking from the weep holes within 8k with aprox 160k on the pump.
The downpipe is one of the 2 great restrictions in the exhaust system of the old body style trucks the pipe is flattened and provides for poor air flow. Replacements are 3" pipe and cost around 100-140 depending on where you purchase it from. Mine's from
DPPI and I'm very pleased with how it installed and since I wasn't doing an entire exhaust it bolted right up to the catalytic converter. If you're replacing the entire system there are downpipes that enlarge once passing the pinch weld of the body to 3.5 or 4". In 99% of the trucks you have to bend the pinch weld for clearance and in some cases the actual floorboard to install the downpipe. The Cat is the 2nd big restriction. some opt to remove it all together others choose to remove the internals leaving the external appearance of a cat for visual emissions inspections. The stock muffler on the OBS Trucks is a straight through design and is acceptably efficent as evidence I offer that Banks does not replace the muffler in their power pack for this truck. If you're looking for moderate increase in power the stock exhaust from the cat back is acceptable if you want lots and lots of power a 4 or 5" system from the cat back would be recommended
The tranny if it's the original and hasn't been rebuilt you have made it far longer than most expect of an E4OD if it's a stock rebuild then more than likely it won't last very long on even slightly increased power. The transmissions can be helped with a shift kit the transgo tugger kit has worked well for many or some have chosen to replace the valve body to improve the shift characteristics with a
Factory tech valve body To use this valve body you MUST have a chip that does not modify any transmission perameters which most do by default. The all out option is to get a built transmisson such as
BTS or a
Monster box which gives you distribution and warranty through the jasper engine & transmission network.
As 95 stroker mentioned the injectors are more than likely on the last leg of their life I can say that mine @ 160 had some problems internaly as well as the stock o-rings were falling apart. If your fuel filter is black then your o-rings are failing and you need to replace them at least. You can get the injectors cleaned inspected and rebuilt to stock at
BDP or a set of mildly modified injectors for a resonable price. Either the tranny savers or the stage 1 injectors will function as a stock injector until you add a chip then they have the potential to deliver more fuel.
As far as increasing mileage of the trucks contact
Jody Tipton and tell him that you are looking for an economy burn on a chip. The intake and exhaust modifications will help maximize the benefits here by allowing the engine to breathe easier.
