Ok so I go through all the posts that I can in the pre 97 forum and I'm left with mixed feelings. I have seen countless posts that contradict each other and I'm really confused as what to do with my truck. First of all, my 90 has a k&n FIPK, E4OD trans, 302 v8, 8.8 3.55 ls. I have a few ideas as far as getting better performance out of it. Not crazy expectations, but just to enhance what is already there. So maybe some one could clear up a few things for me.

1. Does the FIPK really cause these engines to run lean? And if they do what could I do to counteract this condition. Aside from putting stock air box back on. Also if this is the case then would me doing the " timing bump" cause even more problems like pre ignition? I already have the MSD cap/ coil and I'm running 9mm Ford racing wires.

2. I plan on installing tru duals, long tube headers, 2.5" pipe and a 4x9x14 magnaflow Di/do x flow muffler in the next couple of weeks. Now this requires capping off the A.I.R tube that leads to the exhaust between the two factory cats. I plan to use two obd2 style three way ( no A.I.R. tube) converters from magnaflow part# 94006. The tech at magnaflow prescribed these for my application. Now I've seen it posted that without the A.I.R tube, that this may cause premature cat failure. Is this still an issue with the obd2 style cat? Also would putting the o2 sensor on one side of the exhaust, as opposed to reading both sides in factory location, actually enrich my a/f mix due to only reading half of what its supposed to read?

3. Do the Explorer (4 hole) 302 injectors really provide more fuel at 19psi than my stock 1 hole does? I tend to not think so, I mean 19psi is 19 psi no matter how many holes..... Right? Or is it just a matter of atomization?

4. Is there any real benefit in converting from speed/ density to MAF? I have talked to the people at Troyer Performance about a custom tune for my truck and they seem reluctant to do so because I'm not running MAF. if I do convert, will a custom tune allow me to run different cam profiles, widen the timing range, allow for a better a/f mix etc?

5. And lastly. My buddy seems to think that gt40 heads are the "bomb diggity" his words not mine. Lol. Just to satisfy him, will these heads work in my truck being basically stock?

I don't know everything about the way the electronics work in these trucks and I'm not too good with wiring diagrams. So if anyone can please try to explain these things to me, it would be much appreciated. Thanks in advance.

 

1) No. The HEGO sensor will read the difference, if any, and compensate. The FIPK will cause your engine to ingest more dirt. They just do not filter as well as a conventional filter
2) The new style cats do not require an air tube. If you switch to them you do not need one. Reading only one bank will cause no problems as long as the bank you are not reading is functioning properly.
3) It's 19 lbs/hr at 39 PSI. Helps to get the numbers right. The 4 hole injectors flow the same as the pintle injectors of the same rating but they allegedly atomize somewhat better. I would not expect a measurable difference in performance.
4) The only benefit of MAF is that it allows more modifications without upsetting the PCM. Probably not required in your case
5) He's right and they will work on your truck and add measurable performance, especially if you upgrade your intake manifold and T/B to match. However THAT may move you out of the range where your S/D processor is happy and require the MAF conversion.

 

Strangeranger thanks so much for clearing up these things for me. I feel a lot better about the direction I'm taking with my truck. I doubt I ever do the gt40 heads, but just for the sake of asking, what kind of upgrades are out there for the intake and tb? Are we talking about a machine shop, or buying off the shelf bolt ons. BTW what is a HEGO sensor? Is there another name for it?

 

O2 sensor. HEGO = heated exhaust gas oxygen.