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Engine 87 NA - Tune or no Tune needed?

  • Thread starter Thread starter R82148V
  • Start date Start date Sep 17, 2025

R82148V

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May 26, 2020
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Sep 17, 2025
#1
  • Sep 17, 2025
  • #1
Hello everyone.

I'm running stock heads and cam on an 87 NA. Engine upgrades at the moment are exhaust, headers, CAI, Accufab 65 mm TB and a little advanced timing.

I'm starting to see oil seepage from lower intake behind the distributor shaft and its also leaking worse in the back which is running down the heads and giving that burning smell. Sooooo it's time I change the original lower intake gaskets and just thought I would upgrade the intake system to an explorer.

As of right now, starts right up, it idles great cold and hot, no surging, hunting, pulls nice. Engine stays cool with gauge right in the middle or a little lower. Not burning coolant, but I do notice slight oil loss when checking the level. don't know if that's normal or not. Oil stays super clean. No smoke of any kind out the exhaust. KOEO and KOER codes are all good. Cyl balance test comes back good on the first try.

Question is, would I need a tune after or with these mods now including the upper and lower intake upgrade,, would it be ok without a tune and the stock ECM is good enough? Would these mods make it run too lean?
I'm not looking to upgrade any further after the intake is done.
I just dont want to mess anything up or dig myself into a whole.

Thanks for your time!!
 

Bullitt347

I have been doing it wrong this whole time
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Sep 17, 2025
#2
  • Sep 17, 2025
  • #2
If the stock cam remains, you should have no worries.
 
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Noobz347

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#3
  • Sep 17, 2025
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No tune required.

There is no advantage to swapping the intake with E7s. The heads are the bottle-neck.

The only Fox FI intake small enough to bottle-neck E7 heads, is the E6 intake from an 86.
 
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nickyb

I gotta say i never painted my nuts, Never Ever
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Sep 17, 2025
#4
  • Sep 17, 2025
  • #4
Agree,no tune needed.
As far as intake swap, if you already have the explorer intake then go for it,but don't buy it cause like noobz said the heads are the bottleneck.
 

R82148V

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May 26, 2020
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#5
  • Sep 17, 2025
  • #5
nickyb said:
Agree,no tune needed.
As far as intake swap, if you already have the explorer intake then go for it,but don't buy it cause like noobz said the heads are the bottleneck.
Click to expand...
I don't have the intake just yet, but was about to purchase one. The stock intake on there now is the original lower and never been taken off.
I'm getting oil seepage more rear than front from the china wall areas. I believe this is due to just age? Also the car sat for about 15 years so perhaps that dried out the gaskets some too.? Since there is seepage, I wanted to replace the gaskets before something worse happens and though might as well upgrade while im at it is all.
 

Noobz347

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R82148V said:
I don't have the intake just yet, but was about to purchase one. The stock intake on there now is the original lower and never been taken off.
I'm getting oil seepage more rear than front from the china wall areas. I believe this is due to just age? Also the car sat for about 15 years so perhaps that dried out the gaskets some too.? Since there is seepage, I wanted to replace the gaskets before something worse happens and though might as well upgrade while im at it is all.
Click to expand...

If you have future plans to upgrade the heads at some point and just want to slap this other one in there, it won't hurt anything.

Likewise, what I might do is reseal the current intake, purchase the other intake and take your time, cleaning, painting, polishing, whatever, in prep for your next set of heads.
 
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R82148V

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May 26, 2020
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#7
  • Sep 17, 2025
  • #7
Noobz347 said:
If you have future plans to upgrade the heads at some point and just want to slap this other one in there, it won't hurt anything.

Likewise, what I might do is reseal the current intake, purchase the other intake and take your time, cleaning, painting, polishing, whatever, in prep for your next set of heads.
Click to expand...
I like what you’re saying and definitely don’t want to do the job twice. I wasn’t planning on changing the heads but since I’m in there with everything off, maybe I should. I’ve never done anything like this before.
I’m actually hitting up a swap meet this weekend. Anything i should look out for? Nothing crazy but won’t break the bank.
 

General karthief

wonder how much it would cost to ship you a pair
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Wish you were closer, I'd give you one I gots, I wouldn't pay more than a buck fifty for one, you're not in a hurry, call around to a couple salvage yards, oh, and don't fall for the 'it's a GT40 intake' it's not, better than stock, works ok with stock heads, but not GT40, just an explorer, if you are pulling yours off and have an explorer intake do it, otherwise save the dough and plan your modifications.
 
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R82148V

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May 26, 2020
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#9
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  • #9
General karthief said:
Wish you were closer, I'd give you one I gots, I wouldn't pay more than a buck fifty for one, you're not in a hurry, call around to a couple salvage yards, oh, and don't fall for the 'it's a GT40 intake' it's not, better than stock, works ok with stock heads, but not GT40, just an explorer, if you are pulling yours off and have an explorer intake do it, otherwise save the dough and plan your modifications.
Click to expand...
Thank you for the offer! That would have been great! i’ll definitely take your advice for sure!!
 
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