J-Mod

[fastblackmerc]

If you've done the J-Mod, what drill sizes did you use in what holes?

[IwantmyMMnow!]

The attached word doc I got from here and saved to my desktop over a year ago....hope it helps...

[MyBlackBeasts]

If you've done the J-Mod, what drill sizes did you use in what holes?

These instructions are spot on except for the location of the small plastic screen that falls out when valve body is removed. It goes in the RF corner, not RR as stated in instructions: http://www.crownvic.net/tech/4R70Wnotes.pdf (http://www.crownvic.net/tech/4R70Wnotes.pdf)

I drilled #7 to 1/8" also which was in the instructions for older transmissions.

I did the #10 for reverse as the gear delay with OEM drove me nuts.

Have fun, I enjoyed doing the procedure.

The results are great!

[fastblackmerc]

Thanks guys!

I bought a new separator plate (Superior Transmission Parts, Inc. #K092 http://www.superiortransmission.com/Product_Page.cfm?ID=198) and two gaskets.

One question..... Both instructions ID 11 holes on the plate, yet you only drill 7 holes (including the#7 for reverse). What about holes 1, 3, 6 & 8?

[MyBlackBeasts]

Thanks guys!

I bought a new separator plate (Superior Transmission Parts, Inc. #K092 http://www.superiortransmission.com/Product_Page.cfm?ID=198) and two gaskets.

One question..... Both instructions ID 11 holes on the plate, yet you only drill 7 holes (including the#7 for reverse). What about holes 1, 3, 6 & 8?

Do not drill any holes other than: #2, 4, 5, 9, 10, 11

You may find on the aftermarket plate that some of these holes have already been punched out to the larger size.

Just use the indicated drill bit size as a feeler gage and find the ones needing to be drilled.

(don't forget to cut the gaskets holes bigger also)

Per Jerry (Jerry in J-Mod):
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

Have fun, I enjoyed doing mine. :D

[Krytin]

I used a # 39 drill bit for the holes specified (including reverse) and have been very happy for the last 100k miles/135k total.

[cj7chris]

This is Rizzo's JMOD video. I found it very helpful when I did my JMOD:

http://www.youtube.com/watch?v=gbIAKfhrdV0

[fastblackmerc]

This is Rizzo's JMOD video. I found it very helpful when I did my JMOD:

http://www.youtube.com/watch?v=gbIAKfhrdV0

Thanks..... I've seen that video so many times I think I can recite it verbatim.

[VMARAUDER]

This is Rizzo's JMOD video. I found it very helpful when I did my JMOD:

http://www.youtube.com/watch?v=gbIAKfhrdV0

Great and very detailed
Will be doing soon

[Green96]

Per Jerry (Jerry in J-Mod):
Ignore what the article says and do this...
>
> Remove the bottom 1-2 accumulator spring and remove the bottom 2-3
> accumulator spring.
>
>

I have not done the Marauder yet, but when I had the j-mod done on my old Thunderbird I did NOT remove the 1-2 accumulator spring. Removing this spring really makes it slam from 1 to 2. By leaving the spring in I get the quick shifts from drilling out the plate, but the **** is not hard. It was perfect for me, and that is the way I will do it on the Marauder when I get around to it.

If you want the hard shift, go for it an I am not trying to be down on anyone that removed their spring. I just want to highlight the result. I would hate to see somebody regret a mod because it was never explained what this step does, and that it can be left alone based on your preference. Good luck.

[MyBlackBeasts]

I have not done the Marauder yet, but when I had the j-mod done on my old Thunderbird I did NOT remove the 1-2 accumulator spring. Removing this spring really makes it slam from 1 to 2. By leaving the spring in I get the quick shifts from drilling out the plate, but the **** is not hard. It was perfect for me, and that is the way I will do it on the Marauder when I get around to it.

If you want the hard shift, go for it an I am not trying to be down on anyone that removed their spring. I just want to highlight the result. I would hate to see somebody regret a mod because it was never explained what this step does, and that it can be left alone based on your preference. Good luck.

I like neck snapping hard shifts. As close to driving a stick & dummping the clutch as you can with a slop-o-matic. So I removed spring.

Nice thing is with normal driving the shift is quick & firm but not abusive BUT get ont the fun pedal & wee-haa! Slam-bam-thank you ma'am! :D

[fastblackmerc]

I like neck snapping hard shifts. As close to driving a stick & dummping the clutch as you can with a slop-o-matic. So I removed spring.

Nice thing is with normal driving the shift is quick & firm but not abusive BUT get ont the fun pedal & wee-haa! Slam-bam-thank you ma'am! :D

I'm going to pull the springs. Can always put them back in.

[Linkin]

Rizzo on the cvn forums has a great you tube video on the jmod. He is the king of jmod, except for Jerry himself (he is more godlike).

[vegasmarauder]

I have done the J-mod on about 10-15 transmissions now. The only feedback I get is that some people don't like a hard 1-2 shift (especially on early 2003's). If that is not a problem, then all holes can be drilled to the .110 (7/64"). On cars (MM's and others) where the softer 1-2 is desired, then I drill hole #2 to 3/32" and the others to 7/64".

This seems to be the best of both worlds. The 1-2 is not a neck-jerker but the others are just fine.

I always do hole #10, as I can't stand the delayed reverse engagement.

Just my .02 worth.

[fastblackmerc]

Got all the recommended holes drill out with a #39 drill.

Now I just need some alone / Marauder time to do it.

[Krytin]

Cool! Hope you like it as much as I do!!!
Even the down shifts will break the wheels loose!

[justbob]

I'm going to pull the springs. Can always put them back in.

Smart move. Besides, you can always dial back the line pressure.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[Krytin]

Smart move. Besides, you can always dial back the line pressure.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

That's what I did on the 1-2 shift.

[tbone]

Leave the springs in, imho. With Zack tune, dialing back the pressure produces zero results. 1-2 shift way too hard for everyday use with no spring.

Never really experimented with my custom dyno tune pressure settings. I put the springs back in on my last rebuild and I have been thrilled with the results.

[JoeBoomz]

I would agree the springs are best left in and if you want it harder the pressures can be tweaked. 1-2 shift is wastefully hard and induces wheelspin too easily without the spring.

[MyBlackBeasts]

1-2 shift is AWESOMELY hard and induces wheelspin too easily without the spring (Full of WIN!).

Fixed it for ya! :D

[fastblackmerc]

I would agree the springs are best left in and if you want it harder the pressures can be tweaked. 1-2 shift is wastefully hard and induces wheelspin too easily without the spring.

That's a bad thing?

I'll remove the springs, can always reinstall them.

[fastblackmerc]

I did the j mod this past weekend.

The Art Carr deep pan with the drain plug made draining super easy. :beer:

The OEM style filter was still in it's place.

Almost no debris in the bottom of the pan or on the magnetic bolt. :banana2:

Only one spring, removed it.

Used a pre drilled separator plate. Drilled the holes out with a #39 drill bit.

Torqued all the bolts to the proper spec.

Didn't drain the convertor, took 8 quarts of Mercon V to refill.

I was expecting a "slap your momma" "Holy shitballs" 1 -2 shift..... wasn't really there. It does shift noticeably quicker on the up & down shift. Do get a slight squeal on the 1 - 2 shift.

[MyBlackBeasts]

I did the j mod this past weekend.

The Art Carr deep pan with the drain plug made draining super easy. :beer:

The OEM style filter was still in it's place.

Almost no debris in the bottom of the pan or on the magnetic bolt. :banana2:

Only one spring, removed it.

Used a pre drilled separator plate. Drilled the holes out wit a #39 drill bit.

Torqued all the bolts to the proper spec.

Didn't drain the convertor, took 8 quarts of Mercon V to refill.

I was expecting a "slap your momma" "Holy shitballs" 1 -2 shift..... wasn't really there. It does shift noticeably quicker on the up & down shift. Do get a slight squeal on the 1 - 2 shift.


Normal driving the shifts are only mildly more aggressive.

When you get on it then she really starts banging gears! :eek::D

[Marauderjack]

When I did mine the 1-2 shift was ridiculously harsh and after driving it in the rain a few times something had to be done!!:eek:

Installed a Mustang spring which helped some but my tuner did the trick....he turned the shift modulation up some under light throttle but above half throttle she still hits pretty hard!!:burnout:

PCM control is a great thing!!:beer:

Be VERY CAREFUL on wet roads Jim......hard upshifts and downshifts can be SCARY!!:eek:

[Limited360]

Debating this... Without it I leave 11's for 15+ft on the 1-2... Maybe I need stickier tires first! Good info here!

[lji372]

Debating this... Without it I leave 11'a for 15+ft on the 1-2... I need stickier tires first! Good info here!


Agree with what you wrote in blue!!!:D

[Limited360]

Agree with what you wrote in blue!!!:D



Your just jealous I can roll smoke :banana2:


However on a serious note... I need some DR's....

[crownvic05]

When I did mine the 1-2 shift was ridiculously harsh and after driving it in the rain a few times something had to be done!!:eek:

Installed a Mustang spring which helped some but my tuner did the trick....he turned the shift modulation up some under light throttle but above half throttle she still hits pretty hard!!:burnout:

PCM control is a great thing!!:beer:

Be VERY CAREFUL on wet roads Jim......hard upshifts and downshifts can be SCARY!!:eek:

I'm looking to install the springs back in my 1-2 as im not liking the harsh shift. Mind sharing info on that spring? where did you get it from and part #. Thank you

[Marauderjack]

I'm looking to install the springs back in my 1-2 as im not liking the harsh shift. Mind sharing info on that spring? where did you get it from and part #. Thank you

I got it from Darrin and it was just the stock 1-2 accumulator spring for a GT Mustang.......I think it was green??

[crownvic05]

I got it from Darrin and it was just the stock 1-2 accumulator spring for a GT Mustang.......I think it was green??

Is the one off a gt mustang better then stock on marauders and crown vic?

[Marauderjack]

Is the one off a gt mustang better then stock on marauders and crown vic?

It is lighter and allows it to shift quicker than the heavier Marauder spring!!:beer:

[babbage]

I got it from Darrin and it was just the stock 1-2 accumulator spring for a GT Mustang.......I think it was green??

I got a kit from Darrin also, a pre-drilled valve body plate and softer spring for the 1-2 shift. No spring is too much IMHO, I got quick reverse too on the VB. Nice quick firm shifts at light throttle pressure that get a bit harder with throttle. I run a +5% PCM increase in shift pressure with the Jmod and It's good for me but I have a high stall converter which changes it a little.

Anyway +1 on running a softer than stock 1-2 spring. Don't know what type.

[RF Overlord]

Your just jealous I can roll smoke As long as you aren't rolling coal. ;)