Engine Getting my GT40 Intake ported, to Keep EGR or Not?

FireGT1017

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Hey everyone,

So I have a 1995-1997 Explorer upper and lower intake (The explorer intake with provision for external EGR), I am getting them ported from BigDogs Porting. He said he can drill and tap the ACT hole, but from my research there is another hole that must be drilled for the return line for the EGR. I was speaking to some friends about this because I don't know how comfortable I am drilling into a ported intake which may easily crack. They said just to bypass the EGR/Delete it rather than drilling all those holes and wiring the EGR. I looked around on StangNet and saw people talking about how deleting your EGR is better for performance but then I saw many contradicting posts too. My questions are:

1) To keep EGR or to not keep EGR?

2) If I do delete the EGR/bypass it, do I still have to drill the ACT hole.

Sorry guys I'm just a bit confused, I've been reading a lot of different things if you have any questions or need more information please let me know. Thank you all in advance.
_________________________________
Car: 1989 Mustang GT, 5 Speed.
- 75mm Throttle-body
- Engine bored 40,000 over
- 24Lb injectors, MSD ignition system
- E303 Cam
- Stock upper/lower intake manifold
- GT40 Cylinder heads
- BBK Shorty headers
- BBK Cold Air Intake
- Flow Master 40's
 
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7991LXnSHO

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Is this a street car or race only engine?
What computer are you using, the stock or an aftermarket programmable one?
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
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I'm curious to see what people say here. I've had my EGR disabled in a tune when I had an engine from Panhandle in the car and it ran great. That setup had a mass air computer with a chip that they used to tune with. I also never plugged the vacuum line back in after that and it's been running that way for just over 10 years now.....and i went back to a factory computer. Let me rephrase that....I tried plugging the vacuum line back in and it sounded like I stuck a lumpy cam in it. Unplugged runs completely normal. Voodoo.
 
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FireGT1017

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Is this a street car or race only engine?
What computer are you using, the stock or an aftermarket programmable one?

This is a street car, but its my summer time weekend car for spirited driving. It has a stock computer, I will be getting the car dyno tuned after the intake manifold is installed.
 

7991LXnSHO

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To question number 2, the Air Charge Temp sensor has nothing to do with the EGR system. The ACT sensor needs to be somewhere in the intake track. I have read here about how to put it in the air box, but it seems the temperatures will not be the same in the two locations. Drill and tap slowly and it will not be a problem.
Answer to question #1. Do you like breathing cleaner air without hurting performance? I do.
Looking at the list of mods, I could barely hear the Stereo over Dronemasters and no cats. High flow cats and super turbo mufflers are still loud, but I can listen to the radio and stand to drive on the highway now.
 

2000xp8

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I'd say it's a waste of time and money.
Just sell it and buy a better intake.

Dyno tuning a gt40 setup is an even worse use of money.
A calibrated meter and injectors and it would be fine.
Keep the EGR or just use a simulator.
Most likely you could even run the stock meter and injectors since gt40 iron stuff doesn't exceed the stock 19lb injector capacity.

Guys easily make 300-350rwhp without a dyno tune (which has to be at least $500)
Sell the intake, put the porting money (porting an explorer intake to 75mm makes no sense) towards a better one.
Sell the gt40 heads and put the dyno money towards better heads.
You will likely come out with a car that 40rwhp+ more powerful for similar money.
 

7991LXnSHO

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Agree - using the stock computer should not need tuning with a matching MAF and injectors.
Disagree - for street use, a ported Explorer manifold should make a good power and torque in a useable band. One with the internal EGR would be easier to use. But if the EGR will be eliminated, it will not matter.
 
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FireGT1017

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To question number 2, the Air Charge Temp sensor has nothing to do with the EGR system. The ACT sensor needs to be somewhere in the intake track. I have read here about how to put it in the air box, but it seems the temperatures will not be the same in the two locations. Drill and tap slowly and it will not be a problem.
Answer to question #1. Do you like breathing cleaner air without hurting performance? I do.
Looking at the list of mods, I could barely hear the Stereo over Dronemasters and no cats. High flow cats and super turbo mufflers are still loud, but I can listen to the radio and stand to drive on the highway now.

I'll make sure to ask him to drill and tap the #5 runner. Thank you for answering and clearing that up.
 

General karthief

wonder how much it would cost to ship you a pair
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Your stuff sounds good for a fun street car. Very similar to mine.
There are a couple things to consider, Stick to the stock ignition system, lose the msd. Don't need it and they can be problematic,
Look at a better choice for a cam, the e cam is great by 1990 standards and they sound really cool but can be a little touchy at low rpms and in a street car, idling through a parking lot can be a chore, I'm using the stock cam and going to 1.7 roller rockers (don't tell anyone, it's a secret).
The explorer intake, with the lower ported, is a good choice also, torque is king on the street and you are likely not rev'n it above 5500 rpms anyway.
Consider swapping to a street friendly 355 rear gear, best bang for street buck.
Just my opinion.
 
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FireGT1017

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I'd say it's a waste of time and money.
Just sell it and buy a better intake.

Dyno tuning a gt40 setup is an even worse use of money.
A calibrated meter and injectors and it would be fine.
Keep the EGR or just use a simulator.
Most likely you could even run the stock meter and injectors since gt40 iron stuff doesn't exceed the stock 19lb injector capacity.

Guys easily make 300-350rwhp without a dyno tune (which has to be at least $500)
Sell the intake, put the porting money (porting an explorer intake to 75mm makes no sense) towards a better one.
Sell the gt40 heads and put the dyno money towards better heads.
You will likely come out with a car that 40rwhp+ more powerful for similar money.

I appreciate the advice I've read similar sentiments in other posts, the only reason I'm spending money porting my upper and lower GT40 intake is because I got them free with the car, they're already ported so I'm getting a deal thats cheaper than buying a new intake and the porter I chose has videos showing he can make GT40 intakes flow better than a Holley Systemax 2. I'm dynotuning the car because the previous owner said to, I forget his reasoning. It was related to some modification he did, he said he only did a "base tune" and to get the most out of the engine to get it tuned. I'll definetly look into getting aftermarket heads on the car though, I have my eye on either AFR 165's or some trick flows.
 

General karthief

wonder how much it would cost to ship you a pair
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Sounds like you don't jave a definitive plan. Even a street car needs a plan or it can become a chore just to drive to the store and the money wasted with pieces that may not work well together can be spent elsewhere.
Look here for some combos that work with dyno proven results, some of this will be 'old school' but it can give you an idea of what works where in the rpm range you drive around in.
On a side note, some waste their money on 'dyno tunes' because they don't know how to make a miss matched combo work or think it will 'fix' a driveability issue.
 
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FireGT1017

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Your stuff sounds good for a fun street car. Very similar to mine.
There are a couple things to consider, Stick to the stock ignition system, lose the msd. Don't need it and they can be problematic,
Look at a better choice for a cam, the e cam is great by 1990 standards and they sound really cool but can be a little touchy at low rpms and in a street car, idling through a parking lot can be a chore, I'm using the stock cam and going to 1.7 roller rockers (don't tell anyone, it's a secret).
The explorer intake, with the lower ported, is a good choice also, torque is king on the street and you are likely not rev'n it above 5500 rpms anyway.
Consider swapping to a street friendly 355 rear gear, best bang for street buck.
Just my opinion.

MSD came with the car, I'll do some more research and look into it thanks for letting me know.

The E cam in my car thankfully has been good even at low RPM, but I agree with you definetly in the future I'll be switching to a modern cam.

Thanks alot for the reccomendation to changing the gearing to 355, I'll look into it!
 

FireGT1017

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Sounds like you don't jave a definitive plan. Even a street car needs a plan or it can become a chore just to drive to the store and the money wasted with pieces that may not work well together can be spent elsewhere.
Look here for some combos that work with dyno proven results, some of this will be 'old school' but it can give you an idea of what works where in the rpm range you drive around in.
On a side note, some waste their money on 'dyno tunes' because they don't know how to make a miss matched combo work or think it will 'fix' a driveability issue.

I've been looking into that thread, thats actually where I found the person whose going to port the intake. Your right as in I don't have a complete plan yet I'm still deciding exactly what I would like to do thats why I haven't started a build thread for the car. I'll make sure to look over that thread before I decide on any other engine mods.

Yes, that's why I'm taking my mustang to a local shop that specializes in Foxbodies and have him confirm the car actually needs a tune and not something else before going all in. Thank you for lookin out, its greatly appreciated.
 

2000xp8

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I'm not really familiar with that porting work, and while the performance could be legit, I'll believe a ported explorer is as good as a holley when it rolls up 400 to the wheels all motor on a 347.

For the record, not saying he's being deceptive, but as someone that used to just be a number cruncher when it came to performance parts, there is usually more to it.

The next question would be, do gt40 iron heads really need more intake or throttle body to begin with? Typically oversizing the intake hurts the lower end.
 
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Mustang5L5

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There’s a number of threads on corral on the claimed flow numbers. I don’t want to start the same ruckus here, but Tony has a YouTube channel where he compares the flow numbers from a Holley and ported Explorer. I’m still waiting to see a back to back dyno between the two intakes.

not knocking his work, but after seeing his pricing, I just think that money is better spent on a different intake. But I wouldn’t mind seeing more data.

to answer your question, tap the ACT and rear pass coolant boss for 3/8npt, and then pull all the vac ports off the upper and drill/tap for NPT to tube connectors and the vac tree pipe like this

013402DB-9D49-46FF-BBAF-829304E63D4C.jpeg


Do all this first then send it to get ported (with fittings removed)

Keep the EGR, especially if you are using an untuned a9x ECU. Not much to gain by deleting it. Often times people have issues with the way a car runs when they start deleting stuff.

Edit: the brass fitting on the left above the vac tree is only needed on 86-88 speed density cars to connect to map sensor. Plug this if mass air
 
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FireGT1017

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I'm not really familiar with that porting work, and while the performance could be legit, I'll believe a ported explorer is as good as a holley when it rolls up 400 to the wheels all motor on a 347.

For the record, not saying he's being deceptive, but as someone that used to just be a number cruncher when it came to performance parts, there is usually more to it.

The next question would be, do gt40 iron heads really need more intake or throttle body to begin with? Typically oversizing the intake hurts the lower end.

He has videos on youtube if your interested in seeing the numbers. I don't want to quote his numbers just because its gonna open the floodgates for people to go back and forth on this thread about porting vs buying a new one. Not saying you will, just saying theres alot of members and I have email notifications on LOL. Thanks for all your input and i'll keep in mind that the lower may take a hit and need upgrading.
 

General karthief

wonder how much it would cost to ship you a pair
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Are you building a street driven car or a race car?
I understand the 'getting all can get' when planning a street build but in reality it comes down to a few horse power numbers and a couple hundred rpms difference. Not saying that the porting won't be beneficial but also don't over think it.
just say'n
 

FireGT1017

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There’s a number of threads on corral on the claimed flow numbers. I don’t want to start the same ruckus here, but Tony has a YouTube channel where he compares the flow numbers from a Holley and ported Explorer. I’m still waiting to see a back to back dyno between the two intakes.

not knocking his work, but after seeing his pricing, I just think that money is better spent on a different intake. But I wouldn’t mind seeing more data.

to answer your question, tap the ACT and rear pass coolant boss for 3/8npt, and then pull all the vac ports off the upper and drill/tap for NPT to tube connectors and the vac tree pipe like this

013402DB-9D49-46FF-BBAF-829304E63D4C.jpeg


Do all this first then send it to get ported (with fittings removed)

Keep the EGR, especially if you are using an untuned a9x ECU. Not much to gain by deleting it. Often times people have issues with the way a car runs when they start deleting stuff.

Thank you for this well written reply and clearing up the alleged "performance enhancements" offered by bypassing EGR. Cheers Mate.
 

7991LXnSHO

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Now wait, you are endorsing an intake good on a 347, yet questioning if the heads need more intake and TB than the one built for the 302 the OP is using? It sounds like a up combination suggestion to me.

I'm not really familiar with that porting work, and while the performance could be legit, I'll believe a ported explorer is as good as a holley when it rolls up 400 to the wheels all motor on a 347.
...
The next question would be, do gt40 iron heads really need more intake or throttle body to begin with? Typically oversizing the intake hurts the lower end.