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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Had To Get Autolite 2546 For A 88.

  • Thread starter Thread starter billison
  • Start date Start date May 8, 2017

billison

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#1
  • May 8, 2017
  • #1
had to replace a cracked spark plug. The autolight 25's would not fit. Had to get 2546 , that comes up for a 86 model... good guess my motor or heads were downgraded...
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#2
  • May 8, 2017
  • #2
Is it fuel injected or carbed ? Our cars get so cjpped up its hard to tell what the motor came out of unless you get the casting numbers off the block and heads.
 

billison

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#3
  • May 8, 2017
  • #3
88 efi.
 

mikestang63

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#4
  • May 8, 2017
  • #4
3925s?
 

billison

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#5
  • May 9, 2017
  • #5
A couple pics comparing the type I have vs what seems to be the normal plug. The normal plug does not have the extra crown after the threads and has a thicker body that would not let it fit my cylinder head.
 

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billison

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May 17, 2017
#6
  • May 17, 2017
  • #6
Instead of making a new post I figured I'd ask here.

Ok, so the difference in plugs makes me think I do not have the stock e7 heads. I'm now worried I have a older flat tapped motor... is there a easy way to
Check this?

And is there a way to check the heads without pulling them?
 

mikestang63

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#7
  • May 17, 2017
  • #7
billison said:
Instead of making a new post I figured I'd ask here.

Ok, so the difference in plugs makes me think I do not have the stock e7 heads. I'm now worried I have a older flat tapped motor... is there a easy way to
Check this?

And is there a way to check the heads without pulling them?
Click to expand...

From DIY porting:


About the only easy way known to modern science to identify an E6TE casting is to inspect the spark plug hole. Here, there is a decernable difference.
The photo on the left is a close-up of an E6TE spark plug hole. On the right is an E7TE spark plug hole.
Look closely and you can see that the E6TE spark plug hole has a deep recess from the casting surface to the plug threads, while the E7TE spark plug hole does not have the deep recess from casting surface to plug threads. This difference in the spark plug holes is the only 'practical' way I know of to identify an E6TE from the exterior.
 

billison

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#8
  • May 17, 2017
  • #8
I'll check that tonight.

But the recess goes with the plugs I have..
 

billison

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#9
  • May 17, 2017
  • #9
I'm gonna run my camera into a cylinder... the pistons will tell me something
 
F

FoxChasis

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#10
  • May 17, 2017
  • #10
Autolite 2546 = Motorcraft AWSF44 = E6SE and GT-40/P heads
 
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FoxChasis

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#11
  • May 17, 2017
  • #11
Passenger side bottom-front corner of head (near #1 cylinder) OR driver side bottom-rear corner of head (near #8 cylinder), outside of valve cover rail...
GT = GT-40
P = GT-40P
R = E5AE
S = E6SE
T = E7TE
 
Last edited: Aug 21, 2018
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FoxChasis

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#12
  • May 17, 2017
  • #12


On those heads you can see a "T" on the left head and an "R" on the right head.
 
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billison

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#13
  • Aug 20, 2018
  • #13
Ok. Bumping a old post. While I was under the hood today I checked the heads for stamps and found an S. This confirms that I have E6 heads.

At this point I’m trying to figure out what that means as far as the motor. This means I might have an 86 block and flat pistons right? So I need to get my scope in there and look at the pistons.
 

mikestang63

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#14
  • Aug 21, 2018
  • #14
yep. crappy E6 heads with flat top pistons. You need to be careful with cam selection and not get too crazy with duration.
 
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FoxChasis

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#15
  • Aug 21, 2018
  • #15
Could be a H.O. or a S.O. engine. They both used the same E6SE heads in 1986, and continued using them on S.O. engines after 1986.

You'll need to get the engineering ("casting") number and date code from the block to know when it was cast, or even better the VIN from the block to know what the engine is from. Of course that's just the bare block. The internals could have been changed.
 
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billison

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#16
  • Aug 21, 2018
  • #16
We got ourself a bona fide mysterious circumstance . Popped the scope in the plug hole and those sure don’t look like flat tops to me. I couldn’t get the scope to look up so that’s as far as I got.

The guy I got it from said it was rebuilt at some point and had a b cam. It definitely idles like it has a small cam and has a little pep.

I’ll gladly take more pics of that’ll help with the mystery. I have no plan to remove the intake or heads anytime soon, but will be swapping out my cobra intake for my gt40 maybe this winter.

As it stands, I’m gonna guess it was rebuilt and the e7’s were toast and they found and used these. He claimed they were ported but I doubt that.

Any suggestions for anything else I need to check?
 

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billison

I like tinted tail
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Aug 21, 2018
#17
  • Aug 21, 2018
  • #17
Lots of car on but definitely valve reliefs. Some guy on Facebook claims they are silvolite pistons but I dunno who he could tell from the pics.
 

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FoxChasis

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#18
  • Aug 21, 2018
  • #18
That is not a factory piston. That's all I can tell you about that.
 

billison

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#19
  • Aug 22, 2018
  • #19
For now I’m just gonna leave well enough alone and focus on paint and getting it back on the road. I’ll post back here when I swap intakes with anything I find. If I ever start upgrading the engine, these heads will be the first thing to go.
 
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