Jerry's AODE/4R70W thesis

[88grandmarq]

this the original tech article written by Jerry (Ford engineer that designed the AODE/4R70W). skip to page 13/14 for Jmod specs

http://www.tccoa.com/articles/tranny/transmission/index.shtml

[marquisman]

Good article!

[IPreferDIY]

I've been having a closer look at the J-mod specs and have some questions (I guess primarily, but not exclusively, for 88grandmarq):

1. How exactly does hole size relate to HP? In other words, what makes a particular hole size suitable for one range of HP but not another?

I find it curious that Jerry's modified specs for whales (as used in Rizzo's video) are for the 300-450 HP range when, AFAIK, all stock whales were rated for well under 300 HP (around 239 HP for later whales if I'm not mistaken).

2. Would it be okay to regard the hole sizes as being on a continuum rather than being discrete values for particular HP ranges? In other words, if I pick a hole size that is halfway between the low and mid values in Jerry's chart, do I get half the benefit in a linear manner? Or is there some kind of risk of some kind of mismatch that might mess things up?

I find some of my shifts in my 2000 MGM HPP to be okay in certain circumstances. Notably, I found the shifts to be improved just from removing the restrictive trumpet on the air filter box. It was as if the trumpet was restraining the RPM's around the shift points and thereby contributing to softer shifts. In certain circumstances, I can get pretty snappy shifts without a J-mod, and I just want to go easy (and probably leave the springs in). If I find certain holes are already 0.081", can I play it safe and go to something between 0.081" and 0.100" without any worries? Similarly, for slot 1 in the gasket, can I go with something less than 0.100" without any issues?

3. For the sake of clarification, I note that Jerry's chart indicates hole #3 should go to 0.180", but his preceding diagram indicates it should go to 0.160" (which would match hole #1). I've seen 88grandmarq list hole #3 as 0.180" as well, so I would guess the diagram is wrong. Can anyone confirm that 0.180" is indeed the correct value?

[88grandmarq]

I've been having a closer look at the J-mod specs and have some questions (I guess primarily, but not exclusively, for 88grandmarq):

1. How exactly does hole size relate to HP? In other words, what makes a particular hole size suitable for one range of HP but not another?

I find it curious that Jerry's modified specs for whales (as used in Rizzo's video) are for the 300-450 HP range when, AFAIK, all stock whales were rated for well under 300 HP (around 239 HP for later whales if I'm not mistaken).

2. Would it be okay to regard the hole sizes as being on a continuum rather than being discrete values for particular HP ranges? In other words, if I pick a hole size that is halfway between the low and mid values in Jerry's chart, do I get half the benefit in a linear manner? Or is there some kind of risk of some kind of mismatch that might mess things up?

I find some of my shifts in my 2000 MGM HPP to be okay in certain circumstances. Notably, I found the shifts to be improved just from removing the restrictive trumpet on the air filter box. It was as if the trumpet was restraining the RPM's around the shift points and thereby contributing to softer shifts. In certain circumstances, I can get pretty snappy shifts without a J-mod, and I just want to go easy (and probably leave the springs in). If I find certain holes are already 0.081", can I play it safe and go to something between 0.081" and 0.100" without any worries? Similarly, for slot 1 in the gasket, can I go with something less than 0.100" without any issues?

3. For the sake of clarification, I note that Jerry's chart indicates hole #3 should go to 0.180", but his preceding diagram indicates it should go to 0.160" (which would match hole #1). I've seen 88grandmarq list hole #3 as 0.180" as well, so I would guess the diagram is wrong. Can anyone confirm that 0.180" is indeed the correct value?

The JMod was originally developed for Mustangs, Tbirds and supercharged Modular engines. Jerry wrote the article because in the late 90's there were no good shift kits, tuning hadn't reached the levels it is today and guys on the forum were already breaking the 400hp mark.

HP charts were an easy way to estimate what shift speed and firmness should be, but its completely different with newer transmissions since the transmission pressure has increased from the factory.

slot 1 only applies to transmissions 2000 and older, Ford re-designed the valve body in 2001 and the slot is no longer used.

hole 3 has always been .180" and dont see where any of the instructions mention .160"

[IPreferDIY]

... hole 3 has always been .180" and dont see where any of the instructions mention .160"

Near the top of page 13, at the bottom of the first diagram, it says the following under an upward-pointing arrow:
Hole #3
Intermediate Clutch
Exhaust
Open to .160

I guess most people don't notice it.

It seems like a good idea to add Jerry's updated specs for the whales, as well as the ones used by 88grandmarq, so that people can find everything in one spot.

Here's Jerry's updated specs for the whales from http://www.crownvic.net/ubbthreads/u...07#Post1152107, as used by Rizzo in his J-mod video:

"Ignore what the article says and do this...
>
> Remove the bottom 1-2 accumulator spring and remove the bottom 2-3
> accumulator spring.
>
> For holes do this.
>
> Hole #2 is the intermediate clutch feed (1-2 shift). Make this hole in the
> .100"-.110" range. It should be .081" in your plate right now.
> Hole #10 is the reverse clutch feed. Totally optional. If you want it to
> engage into reverse faster when you move the lever, open this up to .093".
> Holes #4 & 5 are the direct clutch feed (2-3 shift). Open both of these
> holes up to .100"-.110".
> Holes #9 and 11 are the forward clutch feed (4-3/4-2 shift). Make both of
> these .100-.110" as well.
>
> So, it looks like you need a drill of around .100" and you should be good.
> When you open up holes 4&5 make sure the hole in the gasket between the
> separator plate and valve body casting, is large enough. These holes are a
> little small.
>
> jerry"

Notably, he doesn't mention hole #6 or the slot 1 in the gasket for -2000. I'll have a look at those when I do my 2000 MGM. Something else notable is that people have complained about the shifts being too harsh with the springs out.

Here are the specs used by 88grandmarq quoted in http://www.crownvic.net/ubbthreads/u...25#Post2901225, and I believe he recommends leaving the springs in:

hole 1 = .161"... #21 drill (actually a #20)
hole 2 = .1015" ... #38 drill (I used 7/64" which is barely larger)
hole 3 = .180"... #15 drill
hole 4&5 = .113"... #33 drill
hole 6 = .161"
hole 7 = not used
hole 8 = not used in this application
hole 9&11 = .125" (aka 1/8")
hole 10 = .089"

Notably, 88grandmarq says not enlarging hole #6 is a mistake: http://www.crownvic.net/ubbthreads/u...53#Post2903753. Another significant difference is that 88grandmarq goes with 0.125" for holes 9&11.

For the sake of erring on the milder side when I do mine, I'm contemplating using a 3/32" (0.0938") drill for holes 2, 4&5, and 9&11, and leaving the springs in. Is there anything blatantly dumb about doing that?

Overall, here's what I'd be contemplating:
hole 1: ensure it's at 0.160"
hole 2: drill to 0.0938"
hole 3: ensure it's at 0.180"
holes 4&5: drill to 0.0938"
hole 6: drill to 0.160" if it's not already
hole 7: if it's less than 0.125", open it up to some extent without exceeding 0.125"
hole 8: ensure it's at 0.238"
holes 9&11: drill to 0.0938"
slot 1 in gasket: if it's less than 0.100", open it up to some extent without exceeding 0.100"
hole 10: drill to 0.0938"

I'll make a point of paying attention to the shifts as they are now and try to get a better sense of which ones need how much. Many thanks for any input.

[88grandmarq]

Near the top of page 13, at the bottom of the first diagram, it says the following under an upward-pointing arrow:
Hole #3
Intermediate Clutch
Exhaust
Open to .160

I guess most people don't notice it.

OK.. I see it now. Must be a typo, this hole should be drilled to .180", IF its not already stamped that size from the factory.

It seems like a good idea to add Jerry's updated specs for the whales, as well as the ones used by 88grandmarq, so that people can find everything in one spot.

Here's Jerry's updated specs for the whales from http://www.crownvic.net/ubbthreads/u...07#Post1152107, as used by Rizzo in his J-mod video:

"Ignore what the article says and do this...
>
> Remove the bottom 1-2 accumulator spring and remove the bottom 2-3
> accumulator spring.
>
> For holes do this.
>
> Hole #2 is the intermediate clutch feed (1-2 shift). Make this hole in the
> .100"-.110" range. It should be .081" in your plate right now.
> Hole #10 is the reverse clutch feed. Totally optional. If you want it to
> engage into reverse faster when you move the lever, open this up to .093".
> Holes #4 & 5 are the direct clutch feed (2-3 shift). Open both of these
> holes up to .100"-.110".
> Holes #9 and 11 are the forward clutch feed (4-3/4-2 shift). Make both of
> these .100-.110" as well.
>
> So, it looks like you need a drill of around .100" and you should be good.
> When you open up holes 4&5 make sure the hole in the gasket between the
> separator plate and valve body casting, is large enough. These holes are a
> little small.
>
> jerry"

Notably, he doesn't mention hole #6 or the slot 1 in the gasket for -2000. I'll have a look at those when I do my 2000 MGM. Something else notable is that people have complained about the shifts being too harsh with the springs out.

These Instructions were updated by Jerry specifically for Marauders, but it applies to all 2001 and newer transmissions. Ford re-designed the valve body in 2001 and slot 1 in the gasket is no longer there. I highly recommend drilling hole 6 because it puts less stress on the direct clutch and speeds up the direct clutch release on high speed/high load 3/2 down shift.

Here are the specs used by 88grandmarq quoted in http://www.crownvic.net/ubbthreads/u...25#Post2901225, and I believe he recommends leaving the springs in:

hole 1 = .161"... #21 drill (actually a #20)
hole 2 = .1015" ... #38 drill (I used 7/64" which is barely larger)
hole 3 = .180"... #15 drill
hole 4&5 = .113"... #33 drill
hole 6 = .161"
hole 7 = not used
hole 8 = not used in this application
hole 9&11 = .125" (aka 1/8")
hole 10 = .089"

Notably, 88grandmarq says not enlarging hole #6 is a mistake: http://www.crownvic.net/ubbthreads/u...53#Post2903753. Another significant difference is that 88grandmarq goes with 0.125" for holes 9&11.

Again, the specs quoted are for 2001 and newer transmissions and I am drilling holes in a new, aftermarket separator plate.

For the sake of erring on the milder side when I do mine, I'm contemplating using a 3/32" (0.0938") drill for holes 2, 4&5, and 9&11, and leaving the springs in. Is there anything blatantly dumb about doing that?

Overall, here's what I'd be contemplating:
hole 1: ensure it's at 0.160"
hole 2: drill to 0.0938"
hole 3: ensure it's at 0.180"
holes 4&5: drill to 0.0938"
hole 6: drill to 0.160" if it's not already
hole 7: if it's less than 0.125", open it up to some extent without exceeding 0.125"
hole 8: ensure it's at 0.238"
holes 9&11: drill to 0.0938"
slot 1 in gasket: if it's less than 0.100", open it up to some extent without exceeding 0.100"
hole 10: drill to 0.0938"

I'll make a point of paying attention to the shifts as they are now and try to get a better sense of which ones need how much. Many thanks for any input.

Understand that only holes 1, 2 and 4,5 affect shift firmness. making the other holes larger will NOT make any changes to shift firmness that you can feel during the transmission operation.

From experience, drilling the holes with a .093" bit will not change much and the gear changes will feel the same.

On your 2000 model transmission, do this;
hole 1 will already be stamped at .160" - no change required
hole 2 will already be roughly .081"-.089" - I recommend you open this hole to .100" (use drill #38= .1015") and keep the factory 1-2 accumulator springs
hole 3 should already be stamped at .180" - no change required
hole 4&5 will already be stamped at .081" - I recommend opening both holes to .110" (use a 7/64" bit) keep the factory 2-3 accumulator springs... at this hole size you will feel the 2-3 shift, but will NOT be harsh or uncomfortable
hole 6 will already be stamped to .125" - I recommend this hole be opened up to .160 (use a #20 drill bit)
hole 7 will already be stamped .078"-.081" - there is no need to drill this hole unless you are manually down shifting 2-1
hole 8 is not used on your transmission
hole 9&11; hole 9 will already be stamped to roughly .081", hole 11 will already be stamped to .110" (or larger) - I recommend you drill both holes to 7/64"
Hole 10 will already be stamped between .078-.081" - typically I drill this hole between .089-.093", but it only affects the park to reverse and drive to reverse engagement speed and firmness.
Slot 1 - the slot in the factory gasket it very thin, open the gasket slot up to .100"
hole 4&5 in the gasket - these holes in the separator plate gasket are very small, use a hollow punch and open these holes in the gasket to 1/8"

It is very common for the factory pressure regulator valve and boost valve to wear and cause pressure leaks. I HIGHLY recommend you replace these 2 valves while you have the valve apart.

[IPreferDIY]

Okey dokey. Thanks muchly!!

[IPreferDIY]

Here's a link to my thread about my experience if anyone is interested:

http://www.grandmarq.net/vb/showthread.php?53381-My-Driveway-J-mod-Experience-2000-MGM-HPP-around-186-350km