hey everyone i wanna make a nice street truck out of my 85 f150 shortbox......how do i go about yanking out the fuel injection and making my 302 into a carb set up.....i want to lower it 3 inches in front and 5 inches in the rear.....and maybe throw some nice 18 inch or 20 inch wheels on it....i want to get the most i can out of my 302 with out porting heads or going into the block willing to do as wild a cam as i can with out hurting anything...i already put in a c6 tranny on it....let me know what you guys think of my idea

 

Well...I hope this doesn't get me slapped.

You ask two competing questions there.

1) What do I think about the entire idea?

Nuts to it. It's a truck. Treat it as a truck. Buy a Lincoln if you want to lower it and drape LED lights on it and run weird wheels on it and ... you get the idea.

2) What can you do without going into the block?

Changing the cam IS going into the block. Better to say "I want to get so-and-so HP, and so-and-so Torque. How do I achieve that?" Or, "I want a low end torque monster", or "I want a high revving speed demon"

Building an engine for a specific application takes planning. Just throwing performance parts at it will probably NOT net you the results you wanted.

 

I agree...you need to know what you want out of it. Also going to depend on just how many miles you have on this old 302.

If you are willing to go into the motor and put a cam in then it all has to be matched up with what you have and what you want. You cannot just put a new cam in and expect results.

The cam needs to be matched with the engine, transmission and gearing and will depend on what heads and exhaust you have and how much weight your dragging around.

For what you're looking to do, you probably just want to tear up some tires so you should be looking at a dual plane manifold with probably a 600/650 carb. I'm just throwing stuff out there as examples...not strict recommendations.

You probably don't want a "wild" cam...if you're wanting to burn up tires you're probably wanting low end torque. Most "wild" cams are looking for WOT type applications and you sacrifice street drivability on the low end. High lift cams are also going to strain your valve train and on an old motor...probably not the thing to do.

question: what makes you want to tear the FI out? Is there something or someone telling you that you will get more performance out of a carb?

 

My question is; Why do you want to take the fuel injection off?

As far as what you want to do with the rest of the truck, there are several people and threads about lowering these trucks, and it's always a hassle. The only way to do it and keep the original suspension is buy some expensive lowering beams. And even then you are stuck with what they give you as far as height. What I would do if I were in your shoes is ditch the whole front suspension and go with something from another vehicle. I believe they make a mustang II suspension crossmember for these trucks, and I would also do some research on bolting in a late model Ford crown vic crossmember in place.

Changing the whole suspension will give you more options for lowering/air bags, and also give you a better more wheel friendly lug pattern. You will find your wheel choices are very limited with the truck 5 on 5 1/2 pattern you have now.

 

I think you've come to the right place and the wrong place with your ideas. The right place because the people here have a huge amount of experience with engines, transmissions, etc as well as these trucks, and can give you very solid advice. But, it is the wrong place because you probably aren't going to like what they tell you - even though it is good advice.

Part of the problem may be perceived. Your handle is hi-rev and that's the opposite of what makes these trucks work. They are heavier than most cars and need torque to get them moving as well as to haul whatever is in the bed or tow what's been hitched up. But, what you are saying is in direct opposition to low-end torque. In fact, your plan has you in the hole from the start. For instance, the stock 302 in these trucks doesn't make much torque down low and won't rev very high either. To fix the lack of torque in a 302 you need a better cam and higher compression, but the EFI system you have won't support a cam change, which fits with your plan to put a carb on. However, you still won't get the engine to wind to produce revs without changing out the heads and probably the exhaust. In other words, with the stock, and probably tired, 302 you have the worst of both worlds - lack of low-end torque and lack of high RPM horsepower. So, without going into the engine you can't achieve much, and if you do go into the engine it will be costly.

Find a good 351W and swap it for the 302 and you'll at least have torque for little money. And, if you really want "hi-revs" then either build up a screaming 302 or put decent heads on the 351W.

 

the reason i am taking out the F.I. is because i want a cleaner lookin engine bay and an option to later on want drop a big block in the truck.....and you guys are right i need to take more thought into what i want from the motor and the performance on this truck......for now i guess all i am gonna do is lower it with some dream beams and a flip kit in the rear......so what is all needed to remove the fi system and throw in a carb.

 

That's a more reasonable approach. Sounds like we are already helping. But, you are missing support from a number of people that could help, and that is due to the way you post.

Many of us, myself included, will not respond to posts that aren't easy to read. We will very quickly go on to others whose posts are easy to read because they capitalize the first character of each sentence, use good punctuation, and make an effort to spell correctly. So, my suggestion is that you make an effort to write in complete sentences using punctuation in order to help us easily understand what you are saying. Doing that will dramatically expand the number of people willing to help you.

 

Ok, note taken on the grammer and punctuation of my post. I really appreciate the heads up on how members of this forum conduct them selves as far as how they are willing to help some one out.

Now, all i need to know is now, how do i swap out my FI for a carb?

 

Good response, good post, and good question.

I haven't done the FI-to-carb conversion, but would suggest you not do it until ready to do the cam, assuming that your truck is running well today, because EFI should give you better response than a carb with a stock setup.

Having said that, when you do the conversion you will find that any change in the system requires a complete change. There is no halfway. And, doing this may cause you problems with your state's emissions tests and certainly violates federal laws. So, if you are still gung ho to go, here are things to deal with:

• Remove the computer and convert to DS-II ignition. You can find a write-up on that in the stickies up front. But, suffice to say that the computer now controls the ignition advance, so the ignition has to be replaced.
• You can remove the various relays that hook to the vacuum lines as you won't have a computer to control them.
• You have in-tank pumps and, IIRC, one high-pressure fuel pump, but the carb can only stand a max of 6 psi, depending on which carb you use. So, you will have to get the pressure down, and I don't believe one of the pressure regulators, like the one Holley makes, will handle the pressure your pump gives. Do some searching on the forum, but you may be able to replace your high-pressure pump with a mechanical pump on the block, or maybe even be able to use only the in-tank pumps. Again, do some research.

Beyond those "minor" points, you should be good. But, it is a lot of work for little, if any, return unless you are changing serious things like the cam. Good luck.

 

Its not a daily diver, its just a project that i want to undergo to build a truck that is not so common in the street truck world.

 

I pulled the fuel injection off a 86 302 that was in a mark VII and put it in my old 80 I had. I had to do more because I wanted the mechanical fuel pump, the v-belt system with the regular waterpump and fan, basically wanted it stock looking to the truck.

If you want to run a electric fuel pump and keep your serpentine belt and reverse fan/waterpump, all you have to do is swap out the distributor and the intake.

You will have to pull your fuel pumps out of the system and come up with a plan there. You might have the dual pump system with a high pressure pump on the frame and a low pressure pump in the tank. You could pull both those out, put a suction pipe in the place of the in tank pump, and buy a aftermarket pump that already regulates itself. Or you could keep the in tank pump, put a regulator on it with a return system and set it to 5 psi.

Use the later model intake gaskets with your intake, and get a small 4bbl 600 cfm carb. For the dist you can try to use the original Ford duraspark system, but since you said you want it clean, you can try one of those HEI Ford units, or you could even put a points dist in place and put a pertronix unit inside it.

 

Instead of swapping out the EFI why not just clean up the engine compartment?
Clean up/hide the wiring and vacuum lines, clean and maybe polish the EFI system, freshen up the painted parts. I think the EFI system will give you just as good performance and maybe better mpg than a carb swap. Cleaning things up wont cost much money, just a little work. The EFI systems were designed to be more customer friendly and produce better mpg. A lot can be done with what you have without spending tons of money.

 

I will have to say I agree with keeping the FI system, you can make all that look prett nice.

But, that's not your question so won't beat that horse anymore.

What comes to mind is the emissions, computer, fuel system as the most challenging and I think thats all covered above. Please think about and look into your laws on the emissions because you will NOT be able to swap over to a carb and keep that stuff functioning properly, if at all. Like stated above, it's all or nothing.

If you're set on a carb, the smaller 600 would do you good. Make sure it's a vacuum secondary (something like a holley 1750) and make sure it has the ford kick-down linkage you will need for that C6. I would recommend an Edelbrock performer manifold. Whatever brand you choose, make it a dual plane type for better low end performance.

I think your entensions are just to make it look better and more like a hot rod. Sounds crazy but I know where you're coming from. But make sure that is your number one priority because I have a feeling you may end up spending a lot of money and being disappointed in the performance. Just swapping out the intake / carb, converting to DS II and taking all your emissions off....will likely not give you any more power and possibly less.

So make sure it's looks you're going for and be satisfied if that's all you get.

On another note....if you're considing making it sound better along with those looks and are thinking headers. You may want to consider a set of shorty style headers. Full length headers will tend to hang low and it is difficult to get the exhaust over the transmission cross member. Since you are going to lower this truck, the headers and possibly routing exhaust under the crosss member, is likely going to result in a lot of dragging exhaust components. With the shorties, you can route the pipe up over the cross member and keep it all up off the ground.

 

You asked us to tell you what we think of your idea, so....

I think it's a bad idea.

I wish I had EFI in my truck (have it in my DD car) it's a LOT easier to start & warm up - especially in cold weather - and the mixture is automatically adjusted as the altitude changes (driving in the mountains) and as the engine warms up.

IMHO modern, multi-port EFI rocks and can't be beat.

 

Kind of like ctubutis said, I would love to have fuel injection on the 460 that's in my '81. I was looking at a system like this: Holley Performance Products Avenger EFI 4bbl Throttle Body Fuel Injection System*550-401 , but it's not in my budget right now. Eventually it will be, and am planning the wiring and such for it.

You said you want a carb and a cleaner engine bay? Maybe for now, just clean things up while keeping the FI. Then, later if you decide to go the big-block route, make the change then. There's more and more hot rods going to fuel injection, and a very good reason for it.

You will also have more room to work in the engine bay while the 302 is out and awaiting the new install. At that time you can place things (holes in firewall for wiring, etc..) where they will better suite the new engine.

I'm not trying to sway you away from doing it, just trying to help you make it easier in the future. And, the money you stick into the intake, dizzy and everything else could go towards getting that big-block in there sooner.

I have been there, making changes and all and now I wish I would've just done it all at once, 'cause now I have extra holes to weld up and all that jaz.