FOX TB Swap Questions.

[Adam95GT]

Why swap to the fox TB....


Well i want to to get rid of the ugly egr tube and intake elbow... now to run the fox set up can i still keep my egr.... IF so how is the egr ran on the fox set up... What would be needed to swap everything over??

 

[ratio411]

I don't know the answer to your question, but I will respond to your question with
a question of my own... Why would you want to keep the EGR??? It is nothing but
hot gas injection into your engine, which is terrible for performance. It is also just
another part to clog or malfunction. Have you ever had a dirty or stuck EGR? They
cause havoc. Just a thought. I have no love for anything that sends dirty and/or
hot air into my engine. Do our engines have a TB heater? I know Ford trucks have
hot water lines that travel through and heat the TB. I tend to disconnect those too.
I haven't found where they are on the SN 95 yet. When I do, they're gone. No heat
allowed in or around incoming air.

 

[99FiveOh]

I don't know the answer to your question, but I will respond to your question with
a question of my own... Why would you want to keep the EGR??? It is nothing but
hot gas injection into your engine, which is terrible for performance. It is also just
another part to clog or malfunction. Have you ever had a dirty or stuck EGR? They
cause havoc. Just a thought. I have no love for anything that sends dirty and/or
hot air into my engine. Do our engines have a TB heater? I know Ford trucks have
hot water lines that travel through and heat the TB. I tend to disconnect those too.
I haven't found where they are on the SN 95 yet. When I do, they're gone. No heat
allowed in or around incoming air.

Where do you get your information?

The EGR system actually REDUCES combustion chamber temps when working properly.

And a TB heater? That is a coolant system to cool down the throttle body after the hot exhaust gasses pass through the EGR valve and into the intake tract. Those models had the internal EGR passage and used an EGR spacer, the coolant would pass through the spacer and cool it down.

 

[99FiveOh]

Why swap to the fox TB....


Well i want to to get rid of the ugly egr tube and intake elbow... now to run the fox set up can i still keep my egr.... IF so how is the egr ran on the fox set up... What would be needed to swap everything over??

And to answer your question Adam, throttle response is improved, idle quality is improved and the engine bay looks alot cleaner. Not to mention, Fox throttle bodies tend to be much cheaper and more plentiful than their SN95 counterparts.

I've done the swap and have first hand experience. I had to obtain a fox throttle body, EGR spacer and EGR valve (if you're keeping it, otherwise you'll need an EGR eliminator plate to mount your throttle cable to). The EGR plug on your car will fit the Fox EGR valve perfectly. You'll also need a fox TPS and TPS plug to splice onto your harness because the SN TPS plug is different. Then you'll need to find a Fox throttle cable, you can get them from Fox 5.0's, thunderbirds, cougars and lincoln LSC's, all must be 5.0. These cars are alot more plentiful in the scrap yards than Mustangs. If you want to keep your cruise, you can get that cable too from a fox and hook it into your cruise control motor.

It's not hard to do and is well worth it IMHO. Oh yeah, you'll have to fab up your own CAI setup. Most people use PVC or weld up mild steel tubing.

 

[ratio411]

Where do you get your information?

The EGR system actually REDUCES combustion chamber temps when working properly.

And a TB heater? That is a coolant system to cool down the throttle body after the hot exhaust gasses pass through the EGR valve and into the intake tract. Those models had the internal EGR passage and used an EGR spacer, the coolant would pass through the spacer and cool it down.

Um...
Don't ask me where I got my info when you are spouting ignorance!

EGR... Exhaust Gas Recirculation
Riddle me this... If you are recirculating hot air in place of some of the
incoming air, how is that cooler than cold incoming air?
Take out the hot air, you replace that volume with cold air. Or at least
much cooler than recirculated exhaust. Recirculated exhaust is also lacking
oxygen. Which means you have lost some volume of the catalyst you need
for combustion. It's all about running your engine hot to keep the cats
fired up and burning. To tell the truth, if you take out the cats, the AIR
pump and EGR become a waste of space. They are there to support the cats.

And exactly how does 200* HOT water cool the TB?
No. It doesn't. It heats the TB and incoming air. The primary reason
for the heat is intended to keep the TB from icing up in extreme cold
weather. Don't worry though, I bypassed the hot water to my LSx TB
in Minnesota and never had icing issues.

Dip$h!t doesn't know this stuff is dyno proven.
I may not have ever had an SN95, but I have been working on
cars for a lot of years and don't care for smart remarks on something
so elementary.:Zip2:

 

[The O.G.]

i thought it was exhaust gas removal

 

[ratio411]

i thought it was exhaust gas removal

No, those are called headers.
Sorry, I couldn't pass that one up!

Seriously though, it is recirculation.

 

[99FiveOh]

Whatever you want to believe chebby boy! I've been around Mustang for a few years now and I'm on my 9th one. I'd like to think I know a thing or two about them by now.

This is merely one of many sites I visited that supported my explaination of the EGR system:

What is an EGR Valve - What Does My EGR Valve Do - Where is My EGR Valve

"The EGR valve, or Exhaust Gas Recirculation valve, is a vacuum controlled valve which allows a specific amount of your exhaust back into the intake manifold. This exhaust mixes with the intake air and actually cools the combustion process. Cooler is always better inside your engine. The exhaust your EGR valve recirculates also prevents the formation of Nitrogen related gases. These are referred to as NOX emissions, and are a common cause for failing emissions testing. Unfortunately, your EGR valve can get stuck, causing NOX gases to build up. You'll know if your EGR valve is stuck or malfunctioning because your car will experience symptoms like rough idle and bucking on accelertaion."

The source for the next snippet: Mustangs FAQ: Part 1

"The coolant circulated to the EGR spacer is there to take heat _away_ from the spacer, not heat it up. The exhaust tube to the EGR is carrying gasses significantly hotter than the coolant, so eliminating the coolant flow will only make things hotter."

Conclusion, don't come in a Mustang site wearing your LS1 avatar and tell me, a Mustang enthusiast what this stuff is for. Do a search on here and many other Mustang forums and you'll find out what I'm saying is accurate.

 

[The O.G.]

 

[ratio411]

The only way it could possibly cool the combustion process is by displacing oxygen,
causing less combustion. Fact is though, cooler air than exhaust gas is being displaced.
If it was so good for an engine, you'd see a heckva lot more racers using EGRs... Don't
see that often, do ya?

 

[ratio411]

Sorry for the hijacking.
I'm done.

I hope you get all the info you need on your TB swap.
Good luck
Dave

 

[mob]

The_Mustang is right, its not a TB heater. It is supposed to cool the combustion process, and the egr spacer is supposed to cool, but mostly for emissions. Its really not necessary though probably why "racers" dont use the EGR because it'll be more work setting it up than its worth. Most people dont delete it because you cant properly delete it without tuning the computer, and its not worth a 400 dollar tune just to delete the EGR. On foxes anyways, not sure how the sn95's are setup.

Id do some research before you come on a Mustang site trying to "school" people on their cars.

 

[ProKiller]

and now to get back on track.....Adam there's a decent list of parts you'll need on the swap on sn95 forums.
Official Fox Body Intake Swap Thread

other than cleaning up the engine bay and deleting the EGR, some think it will gain more HP. Given the difference between a fox and a sn95 with the same engine mods, the fox is usually 10ish HP over the sn95. most attribute this to the throttle body style. they say one 90* bend is better than two 45* bends

 

[95Mustang302]

HA,

Ratio actually countered his own argument with the correct answer.

The fact that the EGR gasses are put into the combustion chamber is how it cools, the egr gas takes the place of o2 and therefore causes a cooler burn. Less o2 = less fire = less heat...

 

[95Vert383AOD]

I have no EGR. I have ran this way for some time with no prob. Then again my heads are not emissions legal. I just hate seeing that EGR making my intake parts dirty. Correct fuel mixture is more important for cyl. temps than the EGR. I believe somewhere in the aftermarket world theres a plug to plug into the EGR plug so the computer still thinks its there. But best way is tuning it out.

Besides if you ever want to use a TB bigger than 75 you wont find it for the SN95. Fox setup also dramatically cleans up the engine bay. I believe Ford was going for maximum clutter on the 94/95 cars.

 

[Adam95GT]

The question is can i pass inspection without EGR without smog but with cats????

I DO have a sn95 65mm TB and elbow...
I Would like to have a 70mm Fox TB set up...


Where does the egr connect to on the fox an egr plate???? WHere does it come from if not on the header im not sure if my TFS/KPI highports have what is needed for the fox set up.

 

[99FiveOh]

The fox setup get's it's EGR gasses internally. The heads have a port on them which allow the gasses to flow through a crossover tube in the lower intake and into the upper. From there it flows to the EGR spacer, out of it into the EGR valve and does a U turn back into the intake tract. If you use all fox parts with a Fox EGR valve and spacer, you'll pass the visual inspection. Now, you metioned not knowing if your heads have the proper provision for internal EGR, I'm not sure either, but if you have all the equipment on there then you should pass the visual.

 

[99FiveOh]

Here's a picture, circled in red is where the Fox's get their EGR gasses from:

 

[95Vert383AOD]

I think most shops don't even look that hard....just don't throw a check engine light and you'll be ok. If it looks like something was supposed to be there they will question it....like a delete pulley or block off plate. If you make its so theres no delete plates or random pulleys that have no purpose in the place of smog pumps then you shouldn't get harassed unless you get inspected at a shop where the inspector is a mustang fanatic.

 

[Adam95GT]

I think most shops don't even look that hard....just don't throw a check engine light and you'll be ok. If it looks like something was supposed to be there they will question it....like a delete pulley or block off plate. If you make its so theres no delete plates or random pulleys that have no purpose in the place of smog pumps then you shouldn't get harassed unless you get inspected at a shop where the inspector is a mustang fanatic.

State inspection here not private.... but the question was more will i pass the sniffer... or will i be off the charts on nox