4.6 thunderbird. easly upgraded? need help.
- Thread starter bagged
- Start date
A little more than that.....I'd say in the 10.3-10.5 range. Still very managable as long as you're running high test though. 
How much boost do you intend to run? You might get away with a small amount of boost( 2 - 4 PSI ) at that higher compression ratio and octane level of fuel. If you intend to run bigger boost, I would use the NPI heads or build a motor to handle the boost. If it was me, I would build the motor to handle the boost.
One of the problems I run into alot with the MN12s, is in the AODE/4r70ws, the 1-2 shift accumulator piston ends up crooked in the piston bore. Sometimes even, on the 2-3 accumulator, as well. If you ever drop the pan on one, look for the one visible piston and snapring, and pull the snapring out. On just about every trans I've done this on, the spring behind the first piston cover is shattered in 3 pieces, and the piston behind the spring is stuck. You can order the revised pistons on Ebay for cheap.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=7930846101&sspagename=STRK%3AMEWA%3AIT"
There is a link to one.
Doing the Jmod is free on these transmissions, granted you have a new solenoid gasket on hand. However, I would recommend getting a complete shift kit, as they come with all new gaskets, springs, check balls, and a manual lever rod. Get a kit, and the updated pistons I linked you to, and fill the trans with Mercon V, and it will shift just incredibly. Not mushy by any sense of the word. I just installed a TransGo kit, and new accumulator pistons on a 95 Cougar with a 4.6, and when you take off like a normal human being, you can't even hear or feel the trans shift. If you romp on it, it will squawk the tires in 2nd every time, and if you manually shift it, you can roast 2nd, and squawk 3rd. In my opiniion, it was the best mod the car had ever received.
I will also reccomend a new torque converter, since the O.E. ones have very weak fins, and tend to slip like crazy after 100k. Even if you get a stock stall replacement, you'd be shocked at the way a new one feels in comparison. Do all of this, get some 4.10s, and say goodbye to traction!
Good luck with your Mn12 hop-up!
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=7930846101&sspagename=STRK%3AMEWA%3AIT"
There is a link to one.
Doing the Jmod is free on these transmissions, granted you have a new solenoid gasket on hand. However, I would recommend getting a complete shift kit, as they come with all new gaskets, springs, check balls, and a manual lever rod. Get a kit, and the updated pistons I linked you to, and fill the trans with Mercon V, and it will shift just incredibly. Not mushy by any sense of the word. I just installed a TransGo kit, and new accumulator pistons on a 95 Cougar with a 4.6, and when you take off like a normal human being, you can't even hear or feel the trans shift. If you romp on it, it will squawk the tires in 2nd every time, and if you manually shift it, you can roast 2nd, and squawk 3rd. In my opiniion, it was the best mod the car had ever received.
I will also reccomend a new torque converter, since the O.E. ones have very weak fins, and tend to slip like crazy after 100k. Even if you get a stock stall replacement, you'd be shocked at the way a new one feels in comparison. Do all of this, get some 4.10s, and say goodbye to traction!
Good luck with your Mn12 hop-up!
how is the j-mod free? it requires me to mill down the pistions and add another fritction and steel... i belive it said you dont use the pressure plate...which i do not like that idea at all, because this can end up in a bent out plate, over clearence and ....fried clutches...i could be wrong
PI cams, intake, GT tub, MAF from a GT, 3:73s , torque converter and such sound like my ticket!
why not drop the extra cash and go for an after market cams? just a bang for the buck deal? or would a after market came be a lil much?
PI cams, intake, GT tub, MAF from a GT, 3:73s , torque converter and such sound like my ticket!
why not drop the extra cash and go for an after market cams? just a bang for the buck deal? or would a after market came be a lil much?
bagged said:how is the j-mod free? it requires me to mill down the pistions and add another fritction and steel... i belive it said you dont use the pressure plate...which i do not like that idea at all, because this can end up in a bent out plate, over clearence and ....fried clutches...i could be wrong
PI cams, intake, GT tub, MAF from a GT, 3:73s , torque converter and such sound like my ticket!
why not drop the extra cash and go for an after market cams? just a bang for the buck deal? or would a after market came be a lil much?
The Jmod only requires you to do a little drill work, and possibly have to buy a new separator plate gasket, if yours gets jacked up during the process. Check out the article over at TCCOA.com
billfisher
Active Member
billfisher
Active Member
i had to post something. screw them. i simply posted a motor to consider and dumba$$ t-bird guys(only to include those on tccoa(you know who you are))
some t-bird guy actuallt had to e-mail me, because they get flamed for suggesting anything different. i didn't post crap until you guys forced me to. i though the gt500 and 05 gt weighed the same. besides, you guys are looking to flame any new ideas, not get your tech right. EVEYONE(nearly) that posted on that site got a crapload of things(specs) wrong so i don't really care what narrow monded t-bird guys think. if it ain't you don't take it personal. i even posted stats and it got flamed. i tried fact, fiction, sci-fi, bull$hit, and you guys flamed it. did i throw stuff out there, of course, but so what. after trying to be civil what do you expect?
if you are personally an open minded ford boy, then try something new. have fun, but don't look to flame anything new that peer pressure makes you follow the crowd.
some t-bird guy actuallt had to e-mail me, because they get flamed for suggesting anything different. i didn't post crap until you guys forced me to. i though the gt500 and 05 gt weighed the same. besides, you guys are looking to flame any new ideas, not get your tech right. EVEYONE(nearly) that posted on that site got a crapload of things(specs) wrong so i don't really care what narrow monded t-bird guys think. if it ain't you don't take it personal. i even posted stats and it got flamed. i tried fact, fiction, sci-fi, bull$hit, and you guys flamed it. did i throw stuff out there, of course, but so what. after trying to be civil what do you expect?
if you are personally an open minded ford boy, then try something new. have fun, but don't look to flame anything new that peer pressure makes you follow the crowd.
Hahahahabillfisher said:
....yeah, I saw that thread. I was going to welcome you to the board until I saw them tearing into you. I reconsidered after that because I thought they might have banned me afterwards on principal, just for being guilty by association. You've certainly got a way with words Bill.
You just came off a little too strong and one sided for them to even bother trying to embrace the 3V idea.You have to take into consideration that the Thunderbird is a different car than a Mustang is. Just because something works in a Mustang does not mean it is going to work in a Thunderbird.
The 5.4 swap requires a lot of modifications to make it work in the MN12 chassis, more than a mustang requires. Those extra mods are going to cost lots of $$$ and the quality of some of those parts required is questionable.
The people at TCCOA are going to need to see hard facts to justify a different type of mod, like a 5.4 3V swap. That is the bottom line over there.
If you thought you got it hardcore, You got off lucky from some of the things I have seen there in the past, I have been a member of that site since late 1999. There was a board update and that is why my membership does not reflect that over there. That also said, I do think you had asked for it with the attitude you went there with.
The 5.4 swap requires a lot of modifications to make it work in the MN12 chassis, more than a mustang requires. Those extra mods are going to cost lots of $$$ and the quality of some of those parts required is questionable.
The people at TCCOA are going to need to see hard facts to justify a different type of mod, like a 5.4 3V swap. That is the bottom line over there.
If you thought you got it hardcore, You got off lucky from some of the things I have seen there in the past, I have been a member of that site since late 1999. There was a board update and that is why my membership does not reflect that over there. That also said, I do think you had asked for it with the attitude you went there with.
I've been there since 2004, myself. You're right though (although Bill was kind of asking for it), there is kind of an uptight vibe at times and a lot of the members there don't seem to have the laid back attitude that a lot of us do here. At least they've got real Tech questions though and not 100-threads a week about the "X vs H" or "Can my Car beat Brand-X". That's one think I'd like to see less of on Stangnet. What I have noticed over on TCCOA though, is that ever second person over there is a Mod........too many Chiefs and not enough Indians if you ask me.TGJ said:
