Power mods and engine ?'s

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Lack of power is a universal problem with the 2.3L mustangs. With only 88 to start with, it's understandable.

On my old 90 I was trying every bolt-on I could think of- I started with the PVC intake (which does help a lot), then later did a cat back (was more for sound than anything else, I guess), and even later on did a longtube header and underdrive pulleys.

You might see a little gain from gutting the cats, but probably not much. Even with my longtube header I kept the main cat in place. Also, a 255 fuel pump would be way, way overkill, besides that a fuel pump is not going to make the car run any better. 2.3's came from the factory with the same fuel pump as the 5.0's, they get plenty of fuel.

The fundamental problem with the 2.3L is that it's a low horsepower engine to start with and it doesn't respond very well to bolt-ons. I wouldn't recommend throwing very much money at it in pursuit of power. If you want to spend money somewhere, put some money into the suspension because you CAN make these cars handle very well. And save up for a turbo swap.

Well stated, yes, turbo swap is the way to go, but having more power is of no benefit if your car lacks the handling. I would improve the suspension and chassis or at least make sure it is in good condition before adding power.

Removing or gutting the cats will do little or nothing unless the one thats on it is already plugged. As stated, a larger fuel pump does not give you more power. The computer will automatically inject the right amount of fuel. A larger pump is needed for serious mods, you will need it for a turbocharged application with more than about 220 hp. Thats more than double the power you have now. Your stock pump should be good up to about 150 hp, and a 100 lph pump will support to about 215. Don't waste your time or money on a craiglist one, you can get new ones for not a lot of money.

cheap mods i would recommend would be the Ranger header off a 1993 or 1994 2.3. They literally bolt in place and bolt up to the original exhaust down pipe. Also, you loose about 20 to 30 pounds of dead weight on the car.

The PVC intake is good - but if you dont have the money right off the bat - you can gut the "air muffler" between the filter and the throttle body.

I have both a 93 and an 88 2.3 Mustang. The 93 had more pwer to start with but I will recommend gutting the cats and the ranger header - it will give you atleast 10 to 20 more (much needed) horsepower. Another thing to do is to block off the EGR tube....if you do the ranger header swap - you will have to almost do that anyway.

If yours is a 5 speed car, you can find an 8.8 Mustang axle and it'll bolt in. If you find an 8.8 with 3.73 or numerically higher gear, this will help in the light to light scene. I had an old Pinto with the 4 cylinder and had a 4.10 gear in it in high school (way back in the 80's) and I would hang with most of the v-8's off the line.

You can put in an 8.8 in with the auto, but you will have to get the driveshaft altered.

Turbo is definitely a more powerful setup - but that takes time and money to get everything to swap - you can do the above mods right now and atleast make the car more bearable.

Other cool thing you can do is to find the 140 MPH cluster from the 5.0 cars in 88 and 89. You have to use 89 or older for your car as they are slightly different than the 90 and up ones (they look the same obut they are different due to the air bags). I acquired an '89 cluster for mine and all you need to do is swap out the speedo or if the cluster you get is better - you will need to swap in the tach. 5.0 clusters goes to 7000 RPM and 2.3's go to 6000.

loudstang said:

I guess my last question is after I get it home (if I do lol) what should be the first things I do as far as maintenance goes. I was thinking oil change high test gas and maybe some fuel additive like octane booster, plugs and air filter. I don't want to spend too much money on the 2.3 because I will be swapping for a v8 next spring (thats the plan at least). He already has a cherry bomb glass pack on the car and something done to the intake. If I can get the car I will post everything in detail.

Thanks for the help

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Changing oil, plugs and filter is good. Don't waste the money on the more expensive fuel - it isn't needed and will actually slow the car down. Higher octane is harder to ignite and isn't needed unless you have higher compression (like a turbo or built motor). Dump a little acetone in the gas tank (like 15 ounces) before you fill it up - it'll help clean the injectors and make the car run much better. Kill the computer memory by unplugging the battery for 5-10 minutes so it can re-learn itself after the new filter and plugs.

If you plan on putting in any kinda stereo another mod that should be done is the upgrade to the 3G alternator. It's a fairly easy and common swap. Once you swap it you'll get 130 amps vs the stock 75 from the original alternator. Basically a little wiring (not much, atleast a 6 gauge charge wire and 150 amp fuse, and bridge one small wire connection) and a little grinding on the mounting bracket and a nut and bolt is all you need to get it done.

I would seriously doubt you could gain more than 8 hp with the above posted mods. Removing the cats will actually cost you performance where you need it most, unless the cat is plugged. Catalytic converters can act as induction devices. Sure they can limit the top end power a little, but only on larger engines moving more CFM. At lower RPM they help scavenge the exhaust from the cylinders, resulting in more torque. The exception would be if the cats are no longer working properly. The reason for this is that as the exhaust passes through the catalyst, unburnt fuel is consumed, the exhaust heats up, and speeds up. This added speed helps create a vacuum in the wake of each exhaust pulse, which helps pull the exhaust out of the engine. Considering the age of the vehicle, the cats may be marginal, depends on how it has been maintained.

The header off the later 2.3Ls does flow much better. I actually have one that I could send you if you wanted. The one I have has the EGR stuff, don't know if you need that or not.

KhanTyranitar said:

I would seriously doubt you could gain more than 8 hp with the above posted mods. Removing the cats will actually cost you performance where you need it most, unless the cat is plugged. Catalytic converters can act as induction devices. Sure they can limit the top end power a little, but only on larger engines moving more CFM. At lower RPM they help scavenge the exhaust from the cylinders, resulting in more torque. The exception would be if the cats are no longer working properly. The reason for this is that as the exhaust passes through the catalyst, unburnt fuel is consumed, the exhaust heats up, and speeds up. This added speed helps create a vacuum in the wake of each exhaust pulse, which helps pull the exhaust out of the engine. Considering the age of the vehicle, the cats may be marginal, depends on how it has been maintained.

The header off the later 2.3Ls does flow much better. I actually have one that I could send you if you wanted. The one I have has the EGR stuff, don't know if you need that or not.

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I understand what you are saying - but i ran my car at the track pre and post mods.

Stock with both inline cats (not plugged) ran a dismal 17.8.

changing just the exhaust manifold and gutting the cats (left the hollow shells in place) dropped the e.t to 16.5.

say what you want, but that was a fairly siginificant gain to me....for just a few hours of work. a better system if you were to worry about the exhaust and keeping up the flow - the best solution would be to ditch the cats, run the 2.25 pipe to a flowmaster then reduce the pipe to 2" on the exit of the flowmaster atleast 12" or more then out.

also, making this change alone netted my MPG going from 23.76 average to instantly getting 25.8 on the next tank and consistently getting between 25.7 to 26.3 MPG.

KhanTyranitar said:

I would seriously doubt you could gain more than 8 hp with the above posted mods. Removing the cats will actually cost you performance where you need it most, unless the cat is plugged. Catalytic converters can act as induction devices. Sure they can limit the top end power a little, but only on larger engines moving more CFM. At lower RPM they help scavenge the exhaust from the cylinders, resulting in more torque. The exception would be if the cats are no longer working properly. The reason for this is that as the exhaust passes through the catalyst, unburnt fuel is consumed, the exhaust heats up, and speeds up. This added speed helps create a vacuum in the wake of each exhaust pulse, which helps pull the exhaust out of the engine. Considering the age of the vehicle, the cats may be marginal, depends on how it has been maintained.

The header off the later 2.3Ls does flow much better. I actually have one that I could send you if you wanted. The one I have has the EGR stuff, don't know if you need that or not.

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pure hogwash.

Increase the pressure in the exhaust and your exhaust gasses will move faster??? BS
Increasing pressure in a system, will increase pressure in ALL directions... that means more backpressure.

KhanTyranitar said:

Catalytic converters can act as induction devices.

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WTF does that even mean.....

Please explain where you came up with 8hp for the above mods... most folks would say a round number like 10 or 15...
What makes you think the limit is 8hp????

What makes me say the limit is 8, because the gains would be more of a percentage of the engines factory power. Since the engine only produced 88 hp when it was new, and I find it unlikey that you will get more than a 10% increase at the most from those mods, the answer is 8 hp. Most folks say something like 10 or 15 because it s a nice round number, and its a guess anyway. But I guess most folks say it, so it makes it a fact by consensus.

Yes, you are right, it increases pressure in all directions, but it won't work its way back to the engine, because the hot exhaust is moving to fast. It will go into the cats, heat up, expand, can't push back to the motor, so it accelerates toward the exit. Because it is now moving faster than it was going in, it also creates a stronger wake behind the pulse. This wake or relative vacuum helps draw out and accelerate the next exhaust pulse that exits the engine.

Induction is the process that defines how any mass of matter moving through a tube, through a fundamental process known as inertia, doesn't want to change its motion. If you blow through a tube, does the motion through that tube really stop the moment you stop blowing? No, it has mass, it wants to keep moving. Forced induction is a process by which this mass is increased and pressurized, the same principles apply. All engines experience induction because both the intake and the exhaust are made of tubes. The efficiency of this induction and the size of all the components defines how much potential power you can produce. This doesn't mean the process is free though, you still have friction to contend with.

A catalyst is a basically acting as part of that induction system, and will accelerate the gases as the pass through it, so long as those gases still have a usable fuel to produce heat with. If there is little or no fuel in the mixture, then the friction of the catalyst will simply slow the flow down, and breaks the induction affect and will produce backpressure.

I would agree, that the catalysts from that time period did leave some things to be desired. They are a little long, that length means more friction, which could exceed their added induction, resulting in a slight power loss, a shorter catalyst would resolve that. The coating technology was not as good, so the efficiency of the reaction was lower, which may interfere as well. And the cell walls were much thicker back then, which would make them more restrictive to flow than a modern catalyst. Then of course, the factory cats, and most aftermarket cats are not really high flow cats.

In the end though, I guess its your car. I just see lots of guys taking of cats, and assuming that because its louder, that they have more power. I'm not going to say its always the case, but I have seen many vehicles, including older '80s vintage vehicles that run worse without them, most often noticed as loss of low end torque and a decrease in fuel economy. The same with modified intakes, sometimes a larger intake helps, but it sometimes kills the low RPM throttle response.

Then of course there is the smell and the safety hazards. I hate driving behind someones stinkmobile. Of course it doesn't bother them, they can't smell their own car. And my brother nearly died from carbon monoxide poisoning, and it came from a car that did have a properly functioning cat. It had a crack in an exhaust manifold, and the small amount that leaked through that was more than enough to cause poisoning. Vehicles that don't have cats produce a lot more.

I would focus on other areas that need improvement first, stock mufflers are terrible, and the stock manifold isn't that great, the later tubular ones are much better. You can improve the intake a lot.

At the end of the day though, the 2.3L does not respond much to simple mods. 16.5 is still slow. Is that quarter mile or a zero to 60 time? Either way, its slow. If you swap in a turbo motor, now you are talking. And on the turbo car, eliminating the cats makes a huge difference. A turbo motor will produce more than double the power your engine does now.

Khan,
I can't respond to all of that, but your theories are a little out of whack.

1. unburned fuel in the exhaust is a waste of fuel. You are better off burning the fuel in the combustion chamber than trying to continue the combustion process in the exhaust system.
2. unburned fuel will destroy a catalytic converter, and dramatically shorten the life of the O2 sensor.
3. increasing pressure in the catalytic converter would increase pressure all the way back to the combustion chamber. You don't get to pick and chose the direction this pressure is applied... it's applied in all directions.

vristang said:

Khan,
I can't respond to all of that, but your theories are a little out of whack.

1. unburned fuel in the exhaust is a waste of fuel. You are better off burning the fuel in the combustion chamber than trying to continue the combustion process in the exhaust system.
2. unburned fuel will destroy a catalytic converter, and dramatically shorten the life of the O2 sensor.
3. increasing pressure in the catalytic converter would increase pressure all the way back to the combustion chamber. You don't get to pick and chose the direction this pressure is applied... it's applied in all directions.

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True, but understand a few things.

1. It is not possible to burn all the fuel in the combustion chamber. You will always have unburned fuel in the exhaust.
2. EXCESSIVE unburned fuel will destroy a catalytic converter. You always have at least some unburned fuel in the combustion chamber. The amounts found in normal combustion are not excessive.
3. As I stated, the exhaust is moving to hot and fast to flow back towards the engine. At high RPM, if the catalyst is too small or is plugged, it can limit the peak power, but at lower RPM, the exhaust does not flow backwards towards the engine, it will always move towards the exit. The exhaust might push in all directions, but realize it has a LOT of momentum in one direction only. Even if it slowed slightly, it would push agains the tail end of the catalyst at the exit and propel itself against the catalyst and continue towards the exit of the exhaust. This principle can be observed on an open air catalyst heater. Fuel and air are drawn together through the catalyzed bed.

KhanTyranitar said:

The exhaust might push in all directions, but realize it has a LOT of momentum in one direction only. Even if it slowed slightly, it would push agains the tail end of the catalyst at the exit and propel itself against the catalyst and continue towards the exit of the exhaust.

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Dude, you are all over the place...
First the exhaust gas is accelerating... now it has "slowed slightly"...

If this pressure wave is going to accelerate the exhaust out the tail pipe, then what is the pressure wave reacting against? What is in the opposite direction of the tail-pipe, because this is where the equal and opposite force is going react.
Any gain made by accelerating the gas from the cat to the tailpipe is going to be offset 100% due to the 'equal and opposite' pressure wave from the cat to the piston.
Remember all that lecture time spent on equal and opposite forces in HS physics?


I've wasted too much of my life pounding replies on the keyboard.
If you choose to maintain this belief, then so be it...

Haha, I know this is an old thread, but it just made me laugh. I never knew that increasing backpressure could help performance. Lets see, more power comes through being able to move more fuel and air through the engine, so cats ad more exaust restriction, witch adds more backpressure, which makes it more difficult to scavange the exaust gasses out of the cylinders, which keeps the engine from pulling in more air/fuel from the intake. Does it make sense that pretty much any mod that people do increases the intake and the exaust flow. Larger cam? Holds valves open longer, or at different timings to increase flow, larger tb? allows more air to inter the intake manifold and increase flow, cai? colder air is more dense than hot air and is the same as pulling in more air, heavier injectors? makes up for the correct 14.7 to 1 air fuel ratio that gas burns best at when using other upgrades. Even a racing go-kart with a 5hp B&S engine uses a straight pipe exaust. Wow, mabe I should have left the cats on every car I've owned.

i run an 88 in the SCCA and the mods that i have found that got me the best results are milling and porting of the head. putting on a 75MM throtle body and a good HIGH performance msd coil with good wires and cap. you would not believe how nicely she will pull. also i am running 4:10 gears AND yes it is speed density i have been clocked on Daytona speedway at 155 mph

DARN i did forget 2 items. im using 19lb injectors from a 5.0 and yes im running a step-up header from racer walsh. header wrap works good too.

Hey guys, found a great website with several different performance ideas for our little 2.3's. Its Ford 2.3L Performance - HotRodHigh.ca. Hope it can help anybody! (It helped me and I felt like an idiot by not thinking of it myself, gained some low end torque on the DIS system just by changing some plug wires around on the intake side coil pack!)

KhanTyranitar said:

1.) but at lower RPM, the exhaust does not flow backwards towards the engine, it will always move towards the exit. The exhaust might push in all directions, but realize it has a LOT of momentum in one direction only.

2.) Even if it slowed slightly, it would push agains the tail end of the catalyst at the exit and propel itself against the catalyst and continue towards the exit of the exhaust.

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1.) How do you figure the exhaust has high kinetic energy at lower rpm when exhaust velocity is lower?

2.) How do you figure expanding gas is going to push on the cat core and casing instead of the gas stream flowing through it? What would it push against as it expands within the catalyst core in such a way that it is propelled rearward without exerting the same force on the exhaust upstream?

Look I don't have to explain this to you, you are not physicists or engineers. I know from experience that very often cars that had their cats removed, even older cars, ran poorly. Its not about backpressure. Its about exhaust induction, not to be confused with forced induction. The key is that the cats are properly sized and placed, and that the cam is setup to match.

Even if the gas pushes against the case and cat core, those are as far as the exhaust is concerned immoveable, so the exhaust will flow in directions it can move. It had momentum going into the cat, so it naturally wants to continue moving in the same direction. It can't push backwards because either the next charge is coming out of a cylinder, which will not only prevent a backwards flow, but will actually help accelerate the next charge. Furthermore, the exhaust manifold has a built check valve. The exhaust port exit is always smaller than the manifold it flows into. This inherently acts like a check valve. The exhaust cannot push back against freely, so as it burns in the cat, it will accelerate in the only direction that it freely can, and that it towards the tailpipe. All you have to do is help it flow in that direction.

Honestly how many of you have actually even dyno tested a stock cat versus straight pipes or aftermarket cats? I cannot say I personally have, but I have seen others test results (when they are honest scientific tests under controlled conditions), and from those test results, the test cat was checked with a stock cat, an typical aftermarket cat, a true high flow cat, and a test pipe. The difference in horsepower between the stock cat and the alternatives was less than 5 hp, and the strongest performer was not the test pipe. It was the true high flow cat. The test pipe came in second. But at less than a 5 hp increase, you really wouldn't notice a difference one way or the other. I also had a buddy who had a built up '88 Grand National. That car was built as a 700+ hp track car, but was also built to be street legal. When it was on the track with cats, it was consistently 2 tenths of a second faster on the quarter mile than without. And yes, they were true high flow cats. The car actually dynoed in at 758 hp at the wheels, and that was with the cats.

At the end of the day, you can do whatever you want with your car. I'm not even really telling you not to take your cat of, but I think the power figures quoted above are a bit optimistic, and there would be lots of other mods I would do before messing with the cat. If I did change out the cat, I would get some real high flow cats.