Didn't ford change the firing order on the 302 after 86? or somewheres around there? So depending on what year 302 you comparing the 460 to, it may or may not be differant.

 

Yes, we're talking about why they made the change. Only the HO 302's in cars got the 351 firing order until the trucks went to a roller motor in the mid 90's. For the most part, the 302's in trucks have the same firing order as the 460.

 

A lot of people really favor speed density. First off there is no claim to increase HP and a lot of people dismiss the conversion as a waste of money especially if you don't have other plans to increase power. I think it's worth it just for the improved drivability. I hated having to devote so much attention to getting the throttle/clutch absolutely perfect to get rolling. If I didn't get it perfect it would either shudder, buck, hesitate, stall or peel out.

Odd that the injector plugs didn't fit. Did the overlay harness plugs fit the injectors? Everything fit like a glove for me.

 

Some comments if I may...

1. Nasty Torx Bolt - why put it back? I replaced mine with an allen bolt, and found at the local hardware store a plastic thing that's about 4" long with a plug on the end that fit the allen bolt perfectly. No more grime, dirt, and gunk getting into the bolt head. If you can't picture this, the next time you're at a home depot or lowes, look at the sockets they have in the tool section. THey are mounted on plastic hangers, with a plug that goes into the socket to hold the socket. This is kinda what this is, but significantly smaller in diameter and longer. I have no idea what it is, but it worked

2. Firing order... Ford changed the firing order to smooth the engine out and place less stress on the rear main bearings. The stress was caused by primary and secondary harmonics and changing the firing order seemed to have tamed that enough for engine reliability.

3. Stroking versus reliability - Stroking an engine simply means you're increasing the stroke length - i.e. the distance the piston goes up and down during each of the four portions of the miller cycle. There are two things to observe here... First, the balance of a stroked engine will be very different than the balance of a factory, OEM engine, and your machinist needs to adjust the balance of the engine for these new parts. Always balance the engine with the flywheel/flexplate, main pulley, damper, and cranknose weight attached if you can. Most shops don't seem to "need" the main pulley and the damper for some reason, but its foolish not to balance the internals with those parts missing. Then mark the crank pulley so you put it on the same way every time, same for the damper if its not keyed. Ford I believe is keyed so its a non - issue. The other observation to make about a stroker engine, is the piston experiences more force at TDC and BDC when it changes direction, because the distance it traveled at the same RPM is increased. Forces in an engine square with RPM so you can see why high revving stroker motors tend to die quickly. This additional force the piston experiences, is also experienced by everything attached to it. Wrist pins work harder, rods are stretched and compressed harder, the crank is pulled and pushed harder, and of course, your bearings feel it as well. Use good quality bearings, of course. Finally, your mains feel it as well which is why cross-bolting or a main stud girdle is often used on more radically stroked engines, trying to keep the forces from tearing the heart of your engine out. Being extremely **** about balancing really can help you here. Balacing won't reduce the increased forces on all the parts, but it will make things run a lot smoother, thus reducing secondary harmonics and not adding to the problem.

Don't forget that factory engines aren't balanced, they are assembled out of bins of parts, which are "within tolerance". This means you might buy a vehicle with a "good reliable engine" where as about of coincidence, you received an engine whereas all the pistons were within 1% of each other, same for the rods, etc. But its also possible to receive an engine (from the factory) from the same bin of parts, whereas all the rods and pistons on the left side of the engine are at the lighter end of the "tolerance" and all the pistons and rods on the right side of the engine are at the heavier end of the tolerance. This results in an engine that dies around 50K or so. And we've all seen that, two cars of the exact same model, options, powertrain, one lasts longer than the other. Thats tolerance at work (and other factors of course).

I'm not knocking stroker motors - please - I'm building one myself (500cid twin turbo stroker), but when doing so one has to consider some of these factors to build it once, and right, so its reliable.

4. Streetability of diesels and other low RPM motors. This is a preference thing I imagine, however having driven diesels and gas pickups pretty much my entire life, there are advantages to both. Gas trucks generally can accelerate faster, because of the availability of higher rpms, whereas diesels generally can pull more, and accelerate just about the same loaded or unloaded. Diesels generally get better mileage loaded, and unloaded. A lot of that is changing with the new breed of pickups out there from Ford, GM and Chrysler-Kraut, so this more applies to the older trucks.

Diesel trucks can be made to be VERY quick simply by playing with the fuel computer, turbo sizing, and propane. Diesels don't like RPMs and the only real reason to rev a diesel is to get you closer to the next gear. Diesels also have very long strokes, and thats partly why they are slow rpm engines. The materials used to make an engine that can withstand an 18:1 c/r are just massive in size and weight. As I said above, the longer stroke significantly increases the forces on the piston when it changes direction at TDC and BDC, another reason why the parts are so massive. The larger the moving parts, the larger the forces, squared. You can see how this could get out of control very quickly... which is why diesel engines (in pickups) have a redline lower than 4K usually. Also why diesel engines in locomotives (which are larger than your entire pickup, and then some) have a redline of about 1100 RPM. They are big.

Anyway, hope this pile of useless information is enjoyable to read.

 

This Is Great!!!!

 

Hey guys....real quick question.
Can one of you guys check the resistance on one of the 8 plugs that goes on the production harness?
I can't locate any plugs....and I was told that I could use a spout connector. I just need to know if the correct part has any a certain resistance reading.

 

Is there a big difference in the performance for the Ford Mass Flow kit vs the Proflow kit when you have some minor performance mods to the engine such as headers, cam, etc? The Ford kit looks easier to install and is about $300 cheaper.

 

Anybody?
Please!

 

My meter got wet and is hosed so I can't check the ohms. Since they're installed it's hard to reach them now. Although there's copper tabs in the plugs I'm not even sure they make a connection or close the circuit since the tabs are so short and uneven. But why else would they be there? If the plugs do bridge the circuits I doubt there would be a resistor but I really have no clue so don't take my word for it.

I think the difference between the FMS and the Proflow is that with the Proflow your getting into it a lot more with the intention of increasing airflow and power while your at it. Mostly by use of a bigger higer perfomance MAF sensor in combination with bigger injectors. You have to do a lot of the adapting yourself. You might have to get a different injector harness and rewire it plus install 1 or 2 new o2 sensors (the FMS kit uses the 1 that trucks come with) Overall it's a more ambitious approach with greater reward.

With the FMS kit your mostly adapting from a stock SD to a more or less stock MAF. It's a good enough kit if your not a full time mechanic and don't know (or want to know) everything about how EFI works. Like me. I've learned a lot anyway though.

 

I would think that if anything, the plugs would have the same resistance as an injector - around 15 ohms. I don't think they should be shorted out, because then two of your injectors wouldn't fire (at least this is my logic with circuits, as current will take the path of least resistance).

 

With just mild upgrades, GT40P heads, headers, and reasonable cam, should the FMS MAF conversion be enough?

 

It'll probably work great, at least up to a point. You'll eventually have to give it more air and fuel to take more advantage. That means larger bore MAF sensor, throttle body and larger injectors. Same with exhaust.

It should be the same as upgrading a stock MAF system but if you just installed the kit you won't be wanting to swap out all those new expensive parts right away.

I'm still unsure about when to reprogram or otherwise modify the ECM. Some say whenever you alter the airflow, others say only after major engine modifications like a major displacement change. Some say just calibrating a new MAF sensor is enough while others say that's just a workaround to fool the ECM. The list of issues and opinions are endless.

For me it was about making it run "right". The kit was made so us SD guys can do things like upgrade heads and cams. To what degree I probably can't afford to ponder.

 

I had severe pinging when I originally installed my MAF conversion (not a kit, wired it myself and used parts off ebay). I checked everything, and eventually traced it to the MAF meter itself. It had been calibrated for 24# injectors (which I was running), and aparantly this is not good. I've read that recalibrating MAF meters for larger injectors is really a matter of hit or miss - some work well, others, like mine, don't. What happens is the voltage curve is shifted down, so that full flow is now at a much lower voltage so that the injector pulse width is shortened to account for the larger flow capability of the injectors. What this also does is tell the comuter that there is less load on the engine and thus it advances the timing much more than it would if it was sensing the actual load on the engine, and so it pings. I got my air meter recalibrated for stock size 19# injectors and all the pinging has disappeared. In my conversations with Pro-Flow, I asked if I would need to get it recalibrated for a 351 (currently have a 302) and he said engine size didn't matter. I think as long as the cam isn't too radical, the MAF system should be able to run the engine just fine without a chip.

 

I read somewhere that the stock fuel pumps and fuel regulators are barely enough for the stock 19# injectors as it is.

 

I have read that too. My thought process was that since it was the same stock motor, it shouldn't need any more fuel than before, but I would have a higher capability for when I am making more power. So the fuel pumps should be enough in that case, since I wasn't using the 24 lb injectors to their full capability.