So, the boyfriend that I plan on never leaving plans on dropping a '95(it might be a '97) 12v Cummins into his 95 ford truck. I know he wants power out of it but I'd like to try to educate myself so that I know what he's talking about. So keep it mildly simple please!
So question time,
- easiest ways to make power
- problems that may occur
- difference between a power stroke and a Cummins
- anything else you feel is basic knowledge

 

Hi Nicole!

Congrats on a boyfriend with good taste

Making power: Power is generated by burning fuel, so burning more fuel nets more power, but you need air to burn the fuel.
So by modifying the injection pump and/or changing injectors you can get more fuel - and then you should swap the turbo to get more air. ( Search for twin turbo or "twins" in the performance section here).

More power also means more stress on parts. Increasing torque necessitates higher pressures in the cylinders, and the stock head bolts and gaskets are not up to it.
Look for O-Ringing, Fire-Ringing and head studs- all this is done to keep the engine together under these higher pressures.

Since the good old 12V was way overbuilt in stock form you can get awayy with a lot of more power than stock, but you will need to monitor the engine more closely. Main factor is the temperature of the exhaust gas, called EGT- keep that monitored with a gauge and you are a step ahead of a lot of expensive troubles. Monitoring boost is also recommended, and fuel pressure for troubleshooting on the 12V.
Depending on the transmission he will use there may be some problems ahead due to the massive torque you can get from these engines.

The difference between power stroke and Cummins-
The Ford engine is a V8 design, meaning you have 8 cylinders in a V configuration, the Cummins you are talking about is an I6, meaning 6 cylinders in a straight line.
The Cummins was designed as an industrial engine and is very robust, but also rather heavy.

HTH

Markus

 

Welcome Nicole.....
First off, cars and trucks are like boyfriends and girlfriends. We generally think we'll be with them forever but in reality most come and go like the wind and only a few turn out to be real gems. The rest on the other hand end up being problematic, cost a lot of money, dont do what you thought they would, and become overall major let downs in your life. So in point.....always keep your options open and never assume this is the one until you have a ring on your finger and there's no doubt he'll take care of you and your up and coming family. Thats why they call it "dating".....

OK, as for the truck and power and all that other techy stuff.....
The everyday vehicles run on gas or diesel. Both use an internal combustion piston crank type engine. But gas engines use a spark plug to ignite the fuel and therefore must always burn a specific ratio of gas to air for optimal power. Of course more fuel is necessary to make more power throughout the RPM range but in gas applications carburetors and injection systems hardly deviate from that air/fuel ratio but rather make the most power on ignition timing changes.

Diesel engines use the same internal mechanical function but operate completely different in relation to the fuel system and combustion. Diesels dont use spark plugs but rather they use an increased compression ratio, which is simply how much the air is squeezed inside the piston area. When air is squeezed tight and fast it will get real hot (approx 1000*F) and will cause any fuel in the cylinder area to ignite. So because diesels dont require a specific air/fuel ratio, they can build more and more power with as much fuel as you can cram in them. Although.....this becomes a problem because they also act like furnaces whereby with all that added fuel burning they simply get hotter and hotter the more fuel there is to burn during combustion. This is where turbo's come into play. As much as turbo's add air to help make the combustion cleaner and more aggressive, turbo's also pump in air which shoves out all that heat in the cylinder from the last combustion process. In the diesel world we call that heat EGT's which stands for exhaust gas temperatures. Most people believe turbos are what makes the power but in reality its the fuel which makes the power and the turbo simply is there to allow all that fuel to be burned appropriately. Again gasoline and diesel are different so the turbo analogy for both does not apply.

So in short, diesel engines are gaining lots of popularity in the aftermarket world because they're major power houses if you know how to crank them up without causing damage to themselves or the drivetrain behind them. Think of it this way..... A performance gas engine will generally pump out HP and torque in the range of 300-400 HP at 5000-6000 rpm and 300-400 foot lbs of torque at 4000 rpm. Add some performance devices and you'll probably gain 30-40 hp/torque somewhere in that power range.
Diesel engines arent bound by the constraints of those same physics as gasoline engines are so normally they produce optimal power at very low RPM ranges. A diesel engine will usually make 200-300 HP at 2000-3000 RPM and 300-400 foot lbs of torque at 1000-2000 RPM. And since the process of air/fuel ratio and fuel timing is different in diesel engines, adding aftermarket HP devices will easily add 60-200 HP and 100-300 ft of torque. So you can easily see why diesels are becoming very popular. The make massive power and are easily modified.

The only problem with diesels is they still have weak links and those weak links are different per the vehicle, the engine, and the application. To best understand what the weak link is in todays high tech easy flow of information world, means just Googling problems, concerns, issues, etc. with whatever truck and engine you're asking about.

If you have any other questions, please do ask.

 

I recently put a Cummins 12 valve into my 2004 excursion. The conversion forum on this site has a lot of information. I used parts from https://www.dieselconversion.com/. They were very helpful plus there is some good reading on their website. There are some more companies selling conversion kits. There is also a Facebook group that deals with Cummins powered Fords commonly referred to as Fummins