th400 shift kit
th400 shift kit Sorry if this is a repeat question and i tried the search. I need some help finding a good shift kit for my th400. Its a stock trans, and wont hold first to w/e rpm i want plus the delayed shifts are no fun either. I was looking at some b&m on jegs and also some trans go ones im just not sure what to choose, what would u guys suggest? Also for any of these kits the trans does not need to be pulled correct?
The B&M kit for the th400 is known to break parts even with stock power.
I like the transgo 400-1&2 kit it does have some good parts that go inside the trans like a 2nd clutch snap ring that will help keep it from blowing the lugs out of the case, and stronger direct clutch return springs.
And theres also a million ways to make your own kit.
I like the transgo 400-1&2 kit it does have some good parts that go inside the trans like a 2nd clutch snap ring that will help keep it from blowing the lugs out of the case, and stronger direct clutch return springs.
And theres also a million ways to make your own kit.
The B&M kit for the th400 is known to break parts even with stock power.
I like the transgo 400-1&2 kit it does have some good parts that go inside the trans like a 2nd clutch snap ring that will help keep it from blowing the lugs out of the case, and stronger direct clutch return springs.
And theres also a million ways to make your own kit.
I like the transgo 400-1&2 kit it does have some good parts that go inside the trans like a 2nd clutch snap ring that will help keep it from blowing the lugs out of the case, and stronger direct clutch return springs.
And theres also a million ways to make your own kit.
I would take it out. As far as installing the parts that go inside just requires a screw driver, needle nose pliers. For the return springs you can depress them with the intermediate race and two c-clamps.
The valve body work might be a bit confusing with this kit if you never worked on one before.
The valve body work might be a bit confusing with this kit if you never worked on one before.
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On The Tree
Joined: Aug 2010
Posts: 104
Likes: 0
From: Warren Michigan
Miller, several questions.
Weight
HP (engine type-ci?)
Shift RPM?
Gear ratio
Torqueconverter.
You don't technically need to buy a "shift Kit" to make a 400 preform good, but the items I listed will determine what mods you will need to do to make it last and preform.
Weight
HP (engine type-ci?)
Shift RPM?
Gear ratio
Torqueconverter.
You don't technically need to buy a "shift Kit" to make a 400 preform good, but the items I listed will determine what mods you will need to do to make it last and preform.
Miller, several questions.
Weight
HP (engine type-ci?)
Shift RPM?
Gear ratio
Torqueconverter.
You don't technically need to buy a "shift Kit" to make a 400 preform good, but the items I listed will determine what mods you will need to do to make it last and preform.
Weight
HP (engine type-ci?)
Shift RPM?
Gear ratio
Torqueconverter.
You don't technically need to buy a "shift Kit" to make a 400 preform good, but the items I listed will determine what mods you will need to do to make it last and preform.
shift rpm is 6400
engine: 6.0L, hp is unknow the tune is not done due to a weak fuel pump. Put down 340 n/a on a mustang dyno and was around 440 on a 100 shot shutting down at 5800rpm running lean and will be a 150-200 shot.
gear ratio: stock 3.42s
torque converter: yank 3600 but showed to be around a 4k on the dyno
Second was a '89 chevy C1500 with a 540, tubbed out rear, etc.
Same results pretty much. The kit has a lot of detailed options to get the shifts to feel like you want them. I've known transgo to change their kit contents and instructions so it would be nice if they're still the same.
Or you can use one of the million ways to make your own kit as it looks like you're about to get instructed to do.
Good luck.
Last two vehicles I put that kit and internal mods were perfect. One was my own '88 Sierra 4x2 with a lift kit and big tires. It ran low 12's in the 1/4 mile. Shifts were perfect, quick and firm automatic and increasing in firmness with throttle. Manual shifts were instant, no delay.
Second was a '89 chevy C1500 with a 540, tubbed out rear, etc.
Same results pretty much. The kit has a lot of detailed options to get the shifts to feel like you want them. I've known transgo to change their kit contents and instructions so it would be nice if they're still the same.
Or you can use one of the million ways to make your own kit as it looks like you're about to get instructed to do.
Good luck.
Second was a '89 chevy C1500 with a 540, tubbed out rear, etc.
Same results pretty much. The kit has a lot of detailed options to get the shifts to feel like you want them. I've known transgo to change their kit contents and instructions so it would be nice if they're still the same.
Or you can use one of the million ways to make your own kit as it looks like you're about to get instructed to do.
Good luck.
9 Second Club
Joined: Aug 2008
Posts: 463
Likes: 0
the governor in the back of the trans governs the shift rpm's especially the 1-2 shift. I bought the b&m governor kit as my tranny(performabuilt) would shift out of first at 5500 even though the shifter was held in first. Ended up leaving one secondary weight along with the two primary weights. It also shortshifted 1-3 at 5 mph and that was with the adjustable modulator turned all the way in . Now it's good.
On The Tree
Joined: Aug 2010
Posts: 104
Likes: 0
From: Warren Michigan
weight is 3300lbs with a full tank of gas
shift rpm is 6400
engine: 6.0L, hp is unknown the tune is not done due to a weak fuel pump. Put down 340 n/a on a mustang dyno and was around 440 on a 100 shot shutting down at 5800rpm running lean and will be a 150-200 shot.
gear ratio: stock 3.42s
torque converter: yank 3600 but showed to be around a 4k on the dyno
shift rpm is 6400
engine: 6.0L, hp is unknown the tune is not done due to a weak fuel pump. Put down 340 n/a on a mustang dyno and was around 440 on a 100 shot shutting down at 5800rpm running lean and will be a 150-200 shot.
gear ratio: stock 3.42s
torque converter: yank 3600 but showed to be around a 4k on the dyno
At 6400 rpms, the direct friction will start to centrifugally apply the direct clutches in low gear(and burn them up). Some of the transgo kits give you stronger springs for the direct clutch. Other company's sell them as well. You will need them.
You will also need to apply both sides of the direct clutch. Trans gos SK with three separator plates ribbited together will also do this. ( an experienced builder can do this modification with out the kit)
Next you will need a early sprag type direct drum and 36 element sprag.
6400 rpm will pop off the snap ring holding the sprag. Several ways to fix this-spiral snap ring off a 4L80E direct drum will suffice.
As far as holding low gear to any rpm, th400s have a safety feature built into them so you don't apply low gear @ 100 and lock up the tires and over rev your engine. Some shift kits will give you a 1-2 shift valve with (with one land missing) and a plug for a hole on the bottom of the valve body. Myself I prefer to leave the safety feature in and just lighten the governor weights to obtain the desired up shift rpm.
You will need more than just a shift kit.
At 6400 rpms, the direct friction will start to centrifugally apply the direct clutches in low gear(and burn them up). Some of the transgo kits give you stronger springs for the direct clutch. Other company's sell them as well. You will need them.
You will also need to apply both sides of the direct clutch. Trans gos SK with three separator plates ribbited together will also do this. ( an experienced builder can do this modification with out the kit)
Next you will need a early sprag type direct drum and 36 element sprag.
6400 rpm will pop off the snap ring holding the sprag. Several ways to fix this-spiral snap ring off a 4L80E direct drum will suffice.
As far as holding low gear to any rpm, th400s have a safety feature built into them so you don't apply low gear @ 100 and lock up the tires and over rev your engine. Some shift kits will give you a 1-2 shift valve with (with one land missing) and a plug for a hole on the bottom of the valve body. Myself I prefer to leave the safety feature in and just lighten the governor weights to obtain the desired up shift rpm.
At 6400 rpms, the direct friction will start to centrifugally apply the direct clutches in low gear(and burn them up). Some of the transgo kits give you stronger springs for the direct clutch. Other company's sell them as well. You will need them.
You will also need to apply both sides of the direct clutch. Trans gos SK with three separator plates ribbited together will also do this. ( an experienced builder can do this modification with out the kit)
Next you will need a early sprag type direct drum and 36 element sprag.
6400 rpm will pop off the snap ring holding the sprag. Several ways to fix this-spiral snap ring off a 4L80E direct drum will suffice.
As far as holding low gear to any rpm, th400s have a safety feature built into them so you don't apply low gear @ 100 and lock up the tires and over rev your engine. Some shift kits will give you a 1-2 shift valve with (with one land missing) and a plug for a hole on the bottom of the valve body. Myself I prefer to leave the safety feature in and just lighten the governor weights to obtain the desired up shift rpm.
The transgo 400-1&2 kit has the stronger direct springs, three layer serperator plate (riveted together), modified 1-2 shift valve.
I also recommended a 4L80E direct drum, which already has the 34 element sprag and spiral retaining clip. Good used assemblies can be bought for under $100.
Sure it can be done without a kit but for someone who is not familiar with it will benefit from a kit with instructions.
On The Tree
Joined: Aug 2010
Posts: 104
Likes: 0
From: Warren Michigan
Now how is any of this different than what I suggested?
The transgo 400-1&2 kit has the stronger direct springs, three layer separator plate (riveted together), modified 1-2 shift valve.
I also recommended a 4L80E direct drum, which already has the 34 element sprag and spiral retaining clip. Good used assemblies can be bought for under $100.
Sure it can be done without a kit but for someone who is not familiar with it will benefit from a kit with instructions.
The transgo 400-1&2 kit has the stronger direct springs, three layer separator plate (riveted together), modified 1-2 shift valve.
I also recommended a 4L80E direct drum, which already has the 34 element sprag and spiral retaining clip. Good used assemblies can be bought for under $100.
Sure it can be done without a kit but for someone who is not familiar with it will benefit from a kit with instructions.
On The Tree
Joined: Aug 2010
Posts: 104
Likes: 0
From: Warren Michigan
First, disassemble the unit and make sure it does not already have one.
They are selling new off shore drums for 75.00 through most major transmission supply houses (transtar, midwest), although Im not sure about using one in a high hp application (they may not have the same strength)
A good used oe one would be desired. Your local supply houses should have both.
A quick google search came up with quite a few locations.
They are selling new off shore drums for 75.00 through most major transmission supply houses (transtar, midwest), although Im not sure about using one in a high hp application (they may not have the same strength)
A good used oe one would be desired. Your local supply houses should have both.
A quick google search came up with quite a few locations.
care to link me? maybe im searching wrong but all i come up with is a few that are like $350 w/ a 34 element sprague and a bunch of links for threads on tech talking about it.