LT1 with a Toyota 4 speed

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Mar 16, 2003
Olympia, WA
I have been searching though the threads and see a lot of posts about people using LT1 engines with different auto transmissions and even SM420s. What I haven't seen is any info about using an LT1 with a H42 4 speed.

Is there anything preventing me from doing this? Is it even advisable? I am really interested in the LT1 as it seems that there are a good number of them available for what seems very reasonable prices.
You need this kit, along with some other components. But it starts here.


FJ40 Chev V8

This is the kit I used to mount a SBC to a stock 4 speed. There are other ways, but this is the best IMO, and the one I am most familiar with.

No problem at all using an LT1 with a Toyota 4 speed. I recommend:
(1) A 4 speed bellhousing
(2) A standard 168 tooth flywheel (externally balanced)
(3) A custom Chevota clutch
(4) A transfer-case mounted 40 pulse Reluctor Ring
(5) Front and rear motor mounts
(6) Possibly throttle cable conversion
Need any help with any of this, lemme know!!!
P.S. send for one of my freebie V8 instruction manuals, can't send electronically, send mailing address---easy deal
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Thanks for the fast replies. I knew that there wasn't much of a problem with the physical connections, but wasn't sure about any issues with things like sensors and electronics. From the sounds of it though, it won't be ground breaking, so that is a good thing. :)
Sensors and electronics won't be a problem, other than the fact that a 30+ year old cruiser doesn't have any. You will be adding all that custom yourself. There are places that will set you up with complete harnesses and ECM's with flashed chips or you can venture into it yourself and build your own. Lots of options, just search a little on here and the web.

Hi All:

If you are concerned about a Land Cruiser H41/42 four-speed transmission holding-up behind the GM LT-1 small block there should not be any problems as long as the transmission is in good shape.


hello ,i am in the middle of a 5.7 tpi swap with stock 78 4 speed , downey bellhousing and t-case support, im using the perfect systeme from painless , it is a nice wiring kit with a small ECM ,there is a similar kit for LT1 part# 65105 you can look in painless performance web site , plug and play , no reprograming noting . just want to give you more info

Thanks for the info on the wiring kit. I will take a look at it if I go the LT1 route.

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