power mods/bbk tb?

[Chrome_Rush]

So I've had this truck a month and am happy with how it performs with the 5 speed and 3.73 rear end, but I know there is always room for improvement. I searched and didn't find much for the first gen. Are there any cheap and or diy mods that help give a bit of a power boost? Maybe a larger bore maf sensor that I can swap on from another ford that doesn't effect driveability? Any little tweaks or inexpensive bolt ons? Also and

I can't believe I didn't think of it until now... I have a bbk throttle body for this truck, I've never owned and never known anyone who has owned anything with the 4.0 but back when I was flat broke I saw the bbk tb out of the corner of my eye on a first gen in a junk yard and figured I might be able to make a few bucks with it. Paid 5 bucks for it never bothered to sell it. That was 10 years ago... Completely forgot I had it until today lol. So one, is it worth the install time, and 2 since I yanked it at a junk yard is there anything special that needs to be done to install to get the truck running properly and everything adjusted right? I obviously don't have the instructions from bbk lol.

 

[Anime]

There are people that put on a 5.0L MAF housing, but it screws things up and it really is better to stick with the stock MAF housing.

Adding a KKM intake or just adding a cone filter and adapter or sticking a K&N or FRAM Airhog drop in air filter makes a difference. You can also drill out or cut a hole in the lower part of the stock airbox to allow more airflow.

Taking up any throttle cable slack also makes a difference, some people don't realize how stretched the cable is and how little the throttle is actually opening when they mash the pedal. The fix is pretty easy.

The BBK throttle body does make a difference, since it allows more airflow, BUT it's really only worth it with other mods, like a higher flowing air filter and either a catback exhaust or at least a higher flowing muffler.

There's also mods you can do to the stock TB that gives similar airflow improvement to the BBK.

Given the price and rarity of the BBK TB, it might be worth it to sell it instead and mod the stock TB.

 

[vroomzoomboom]

i will also add if you put a larger throttle body on, it will only work as good as the opening behind it. as in, if you have a 70mm throttle body going on a opening that is 60mm (just a example) your still only going to get what the smaller of the two openings will flow

 

[Chrome_Rush]

Well it had no exhaust from the cat back when I bought it so I welded on about a 2 foot strait pipe to a dynomax turbo muffler and just threw a turn down on it. So after that cat it's a strait piece of pipe to the muffler then a turn down dumping before the axle eliminating all the bends over the axle. That should flow a lot better then stock. I'm not sure if that dynomax cat back might flow better but I doubt it since it still goes over the axle.

I know I have a few maf - cone filter and at least one spare cone filter so I might as well use it. I may just throw an air hog in it though. Even though the stock box is restrictive I would rather pull in cooler air from the fender then hot air from the engine bay with a cone filter. I will have to take a closer look at how this box is setup. As for the bbk I figured since I have it I might as well use it. I just didn't want to bother with the install if it was one of those parts that do nothing. Sounds like with my exhaust it might help a bit. I was also curious if people tend to have issues getting it to run properly after install. Which comes back to is it worth the install.

As for the maf I completely agree. Anyone who actually understands how the obd1 system functions and how that sensor reads and functions wouldn't mess with it unless they knew what they were doing. The o2 can only adjust for the parameters being out of whack so much. And at wot they don't adjust at all. Causing a lean condition. Adding hair flow to the maf without tuning for it means more air is coming in then the sensor is reading = lean condition. There are a few things you can do to trick the computer. On my v6 5 speed tempo I added a much larger maf (stocker is TINY I believe 45mm) full cost of made cai tb work and a very nice flowing exhaust. It was so lean even with the 02 sensors it wouldn't even stay running lol. Yanked out the stock 14lb injectors and tossed in some 19lb from a 5.0. This made it run really rich. Eyes watering rich. Tossed an adjustable fpr from a fox body 5.0 on the fuel rail (direct bolt on) turned the fuel pressure down a hair and got the air/fuel ratio right. I probably could have just kept the stock injectors and turned the pressure up a few psi and had the same effect but I had a feeling the 14lb were close to maxed out in the 3.0 Vulcan and I planned to add ported heads and intakes down the line so I just upgraded the injectors. With this 4.0 already using the 19lb injectors I know they still have some room for more flow so a simple adjustable fpr if there is one that will bolt up (haven't looked at it yet) turned up a few psi may compensate for the loan condition and it would do it across the board even at wot.

 

[mr cribb]

I swear I must have been the only person to utilize an aftermarket intake and a 302 MAF sensor WITHOUT any drive ability issues.

The 5.0 housing was used with the 4.0 sensor. I used this thing for 3.5 years no issues at all.

Yes it was a hot air intake, it was done on the cheap just to see if I could and it worked.

 

[Chrome_Rush]

Little update. Battery took a dump this morning so while I was under there already I swapped the tb. I'm guessing whoever had it before never touched the adjustment screw on the throttle cable. It was going completely closed after install and the throttle was sticking a bit due to the slack and the blade was only opening 3/4 of the way. A quick adjustment of the screw and it's idling smooth at around 900rpm. Put a brick on the gas pedal with it all the way down and confirmed the blade was opening completely.

I do have a better flowing exhaust which has to aid in this but as of now just a new standard paper filter in the stock box and I can say this made a very noticeable different. It pulls easier and stronger through the entire power band and has better throttle response. Both of which are even more noticeable with the 5 speed. Launches are much smoother and requires little to no gas on takeoff. It just seems to flat out run better. Driveability is definetely improved.

 

[Nedwreck]

I ran a maf housing off a 95 Limited for awhile. Later I got one off a crown vic or whatever i saw at the yard (a v8 car) and it was the same as the 95 one lol. not sure if the 95 was stock btw. No issues on a 92 in five years now..

Some of this maf housing swapping stuff might matter with the early batch fire vs. later sequential fire injections idk.

 

[mr cribb]

Glad I'm not the only one that has used a non stock mass air housing.

I also went one step further and used a set of headers and high flowing exhaust. Was it so furiously fast I brag about it, no but every little bit helped move a 2 ton brick down the road a little easier.

I bought the headers because it was a good deal and my old manifolds were telling me that they weren't going to play nice in removal.

Short version is real super awesome power like a V8? No

I simply bought and or used items as an experiment with results that I liked.

 

[Chrome_Rush]

The larger maf housing may work. And without driveability issues also. But is it going to gain you any power? No. It may not be lean enough to cause issues but it IS running lean. A lean a/f ratio may also trigger the computer to change timing in order to run properly. None of which help in the power department. Just because there are no driveability issues doesn't mean there are no issues. The computer is compensating making it run as it should. But it's not running optimally and not performing as well as it should. A bump in fuel pressure would overcome this issue and essentially trick the computer. Left as is though it's causing issues. You may not see or feel them but it is.

Honestly for the size of the vehicle and it having the 3.73LS rear I'm quite happy with its performance. I was expecting it to be a slug. When I add the 31x10.5 all terrains I may go find a 4.10 8.8 and steal the gear assembly. I don't really want to lose any performance. I've never had an 8.8 apart though so I'm not sure if the gears and LS will come out as an assembly like in my sierra or if it's all seperate

 

[mr cribb]

Point made.

 

[DymondD]

I run this combo on my 93 ex, BBK, 4.6L Mark8 aluminum MAF housing. I like it. Added 3mpg. and like chrome rush said, it launches nicer, mine has noticeably more power. Fuel Trim is good, checked it a couple times. only problem i've had was the tps wouldn't drop low enough at idle, causing the light to come on.

 

[mr cribb]

If anything, mine ran richer with what I had done. At least it smelled that way.

All I can say is that I consistently got 22 mpg and it ran like a raped ape.

I won't argue that fuel trim was off and it's not recommended but man it was fun. Never had an engine light on either except when the mass air sensor was unplugged.

 

[Chrome_Rush]

Your seeing improved mileage because it's running lean mainly. Smelling fuel could be a number of other things also. Something else reading slightly out of norm causing the computer to dump in more fuel. A fouled spark plug letting unburned fuel strait out the exhaust. Even a slight miss. The issue is more on startup and wot then anything g in between though. At part throttle and after the engine is warmed up and the computer goes into closed loop the computer can adjust for the lean condition. At WOT the computer doesn't make these adjustments. It doesn't cold in open loop either. A lot of people used to do similar in the carburetor days to save a little on gas and increase mileage. The would lean out the carb a bit so it still ran ok but not optimally. Used a little less gas at the cost of a little power. Just back off the fuel adjustment until it just started to have running issues then just tweak it back up a touch. Same thing in theory when your running wot and on a cold engine.

 

[mr cribb]

Good to know. Finally a solid explanation of why it isn't necessarily good to use what I did.

Thanks

 

[Chrome_Rush]

How the computer works with all the sensors and what different things can do and how all the sensors work together to get everything g correct can get confusing lol. I have done A LOT of research and tweaking and tuning on obd1 cars and tried just about everything. If you bumped your fuel pressure up 2 psi it would truck the computer for this mod though. At wot and cold it uses base settings in the computer for all the sensors. Your adding more air then it's designed and the injector pulses are timed for that amount of air. So you have more air and the amount of fuel you would need for the amount of air stock. Add that 2 psi the injector pulses will stay the same but inject a bit more fuel every spray countering the lean condition and essentially tricking the system. At cold startup and wot your a/f is correct now and you will actually get the benefit and power from the extra air when the computer won't adjust the injector pulses to compensate like it will at partial throttle.

 

[mr cribb]

Interesting