SBC in fj40 with 3speed...clutch alternitives???

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I've searched the archives and can't find the info i'm looking for.

I did find lots of info on 4speed clutch alternitives to the $300 clutch kit from AA.

I am picking up an old downey adapter tonight (can post pics if needed)

It's not the plate to GM bellhousing adapter it's a full bell housing adapter.

I'm lookin for an alternitive clutch/pressure plate combo to use inplace of the 300 buck AA set up.

I also need to know what kind of throw out bearing i will need to use. I know that the 4 speeds re use the LC T/B but have no idea on 3 speeds

thanks in adavance!
 

Gumby

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I believe any old Chevy p-plate and clutch will work with a three speed.

I could well be wrong, but I'm pretty sure the correct answer is either in the wiki or the old tech links.
 
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i wouldn't trust wiki for beer trivia....but mud tech...i'd put some cash on that!

i'll look.

anyone with real time experience would be great. I want to hit up carquest on my way home and order my parts.
 

reddingcruiser

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In my first FJ40 (30 years ago) I used the Downey adapter and the stock Chevy pressure plate (diaphram type) and disk in my 3-speed/SBC conversion. the spline count is the same but the is a few 1000ths difference (smaller) in the spline width, but it never affected the performance. If I recall, you also need to change out the pilot bushing to accept the FJ40 input shaft.
 
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cool, any idea what year/vehicle clutch set up you were using and do i use a 40 pilot or do i need to source it from AA?


did you reuse the 3 speed throw out bearng?
 
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My 74 came with a factory 4 speed and a 3 finger type clutch (standard for 3 speed). This leads me to believe that the clutch would be the same for both transmissions.

For my 350 conversion to Toyota 4 speed, I followed Downey's Instructions and used a "standard 11 inch low diaphragm type clutch". Many parts guys had trouble with this... I ended up bringing in a Toyota diaphragm type clutch, and asking for a Chevy one like it. They matched me up with a 11" low diaphragm LUK clutch that was used in a host of Chev vehicles in the early 1970s.

I also used a stock Chev pilot bearing. This combination has been working well for 15 years... Even behind a 300 hp motor and with a 17 year old kid learning to drive stick on it.:D
 
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ok

i'll get a 169 tooth flywheel
low profile chevy 10 spine clutch/pressure plate it 11"
stock chevy pilot bearing
stock land cruiser thorw out bearing


i have the 360 downey bellhousing

any idea how i have to mod the push rod coming out of the slave to fit the downey clutch fork?

i'm assuming i have to cut it...or is there a special push rod i have to use?
 
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While the Chevy 10 spline disc will fit on the Toyota input shaft, technically the cut of the splines is different. Chevy splines are square, Toyota are tapered. There is a risk of slop or premature wear. Some of us, have a Toyota disc hub mated with Chevy disc material. That way there is no slop or wear on the input shaft.

https://forum.ih8mud.com/40-55-series-tech/418205-what-clutch-have-i-got-need.html

There are also many who run the Chevy disc hubs without any issue so it's your call.

I didn't have to cut my push rod - it adjusted up just fine although I've seen some posts where people have had to make modifications.
 
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ok

i'll get a 169 tooth flywheel
low profile chevy 10 spine clutch/pressure plate it 11"
stock chevy pilot bearing
stock land cruiser thorw out bearing


i have the 360 downey bellhousing

any idea how i have to mod the push rod coming out of the slave to fit the downey clutch fork?

i'm assuming i have to cut it...or is there a special push rod i have to use?


Mine used a stock 2F fork. I think I had to shorten my pushrod. The slave mounted onto the belhousing using a piece of 1/4" bar stock about 6-7" long. The bar had three holes in it. The first was bolted to the belhousing closest to the fork, the second bolted through the slave/bar/housing, and the third bolted through the bar and slave.

There is one so so pic here... https://forum.ih8mud.com/40-55-series-tech/448066-sbc-swap-manual-steering-2.html
 
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my slave push rod is non adjustable.

I've heard some 40 rods were adjustable (also some 60's)

I'm thinking i might need a thicker push rod that is adjustable.

Will my yota disk work with any low profile chevy pressure plate?

It's a newer clutch and in great shape

and what year GM vehicles had this low profile plate?

I looked up a 85 c10 2wd at orileys (10 finger pp and 10 spline clutch disk)

i also looked up the luke 04-072 IIFC and it looked like a standard clutch, not low profile at all!!!
 
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Lots of people use the Chevy clutch disc on the Toyota input. Years and years of lots and lots of people and in the real world it causes no problems.

The "Three speed" and the 'Four speed flywheels, and pressure plates are completely different. The clutch disc is the same. The forks, throwout bearing and fork pivot are different too.


But... WHY would you even bother to do the work to install a smallblock in front of a Cruiser THREE SPEED transmission?????

In complete seriousness you could not pay me to do that combination. You are better off to leave the rig sitting until you can do it right and put a 4 speed in there.

That three speed is worth a few cents or maybe a buck or two as scrap. That is the only value it has IMHO.


Mark...
 
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the rig is my DD...blew up the day after i traded.

got a great deal on the 3 to SBC adapter and SBC motors are a dime a dozen.

Not to mention i have 2 3 speed trannys on hand.

Can't leave the rig on blocks!!!

Eventually i'll throw in a 700r4 but until then i need my vehicle.

I thank you for the input but i really need to know what chevy vehicles had a low profile pressure plate and 10 spline disk.
 

pbgbottle

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you want this pressure plate see pic CA5473 not sure what kit it comes in

but the list of vehicles which used this pressure plate is in the thread NikP linked to

see how the fingers lay flatter than the usual pressure plate.
this is a short throw quick Ratio diaghram type pressure plate.



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Why not combine that flat GM 11" pressure plate with a stock LC clutch disk? The 275mm LC clutch works out to 10.8" and has the correct tapered splines in the hub?
I don't own one and haven't put one together (V8 LC) but thats the approach I would try :meh:.
 
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to get the proper clutch/pressure plate/pilot bearing combo ask for a clutch for a 1968 checker marathon.

11" short throw disk.
 

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