How to Install a LS to TH350 Transmission Adapter Kit

Adapting an LS engine to an older TH350/700R4 transmission. You can do this at home, and we offer a kit that makes this installation simple.
One thing you will encounter is that an LS crankshaft is usually about .0004 shorter. To accommodate that with an automatic transmission, we offer a dished flex plate to bolt onto the back of the crankshaft. This allows you to bolt on your torque converter to keep everything where it needs to be.
Parts from this episode:
Gen III GM LS V8 to TH350/700R4 Transmission Adapter Kit www.speedwaymo...
0:16 LS Swap Transmission Options
0:34 LS Swap Flexplate
1:11 LS Swap Torque Converter Spacer
1:31 LS Swap Transmission Adapter
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[@johnbehneman1546]

GREAT VIDEO JOE!!! GREAT UPGRADE AS WELL. SIMPLE, EASY & BASIC. SOMETHING TO CONSIDER. THANKS FOR SHARING!!!

[@aurktman1106]

Good timing on this video, I may be doing this soon.

[@speedwaymotors]

Awesome! We'd love to help you out!

[@suzuki06g]

Sweet!, so now I wouldn't have to oval out the flywheel holes to bolt on the torque converter - right? Also, what stall converter do I need for a stock LS 5.3 when mating up to a TH400?

[@WickmanC6]

Purchased your kit for 5.3 to turbo 350 THANKS

[@speedwaymotors]

Thank you! Good luck with your build!

[@sitrucjr]

Did you install it yet?

[@javierrflores]

Awesome Video!

[@jamesdean5087]

I have seen the flex plate with adaptor for older transmissions like TH350/TH400 but what solution do you have for a 700R4? The 700R4 requires a TV cable .... what solution do you have for this if I want to use the factory ECM? thanks

[@PeterHatch-mx7zc]

How about the kick down cable to mount to throttle body drive by cable brackets kit

[@larrykittell726]

In the write-up it states that the difference between the LS and an older engine is 0.0004 which is not even half of a piece of paper. In the video, it says 0.400 which is 1,000 times more. You should correct the written part to avoid confusion.

[@oklahomasquares]

I use the GMC savanna van flexolate. No adapters or spacers required. Is this uncommon?

[@justinw523]

If the Savanna Van had a 4l80e then the flywheel from it would bolt right up to a 350/400 turbo and 700/200r4. I bought this flywheel kit before I learned that a 6.0 or 5.3 with a 4l80e flywheel will bolt right up to a old school transmission without any spacers or adapters

[@mikemellina3022]

@@justinw523how’d this work out for you in about to do the same

[@justinw523]

@mikemellina3022 Yes it did long as it came out of a Savanna Van with 4L80e the flexplate comes with it’s own adapter

[@CamaroKevin84]

What about a pre97 4l60e to LS?

[@streetglide84hog34]

How much for kit?

[@UFPTX]

If you want to get real sporty adapt an LS 4L60E to a GM350.

[@dashawngary824]

Will this work on a 5.3 ls motor?

[@speedwaymotors]

Yes it will! In fact we're using a 5.3 LS in our C10 build! Here's the episode where we use this adapter kit: th-cam.com/video/CeoWLj4nkl0/w-d-xo.html

[@thehatefull1761]

This adapter kit will push your torque converter off of the pump if you tore the torque bolts down do not do this or it will ruin your transmission or your transmission will not go in gear these guys don't know what they're talking about you need longer torque converter bolts with spacers

[@TonysHotRodGarage]

I'm thinking it's probably you who doesn't have a clue! Go back to your video games little boy!

[@justinw523]

Yep you are correct there’s a TH-cam video that shows the gap between the flexplate and torque converter holes some aftermarket torque converters don’t need a spacer but more than most do need them, they are selling China eBay kits with there speedway name on it and not knowing wtf they are doing that’s the difference between someone just looking to make a buck and one that actually takes pride in there work and selling it to the public