Lz9 + 4 spd manual trans in 86 GT swap

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jdv
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by jdv »

This looks like an excellent solution to the 3x00 swap problem.
ericjon262
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by ericjon262 »

I have a prototype welded and ready to ship, let me know where it needs to go and I'll get it in the mail.

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jdv wrote: Thu Dec 14, 2023 7:13 pm This looks like an excellent solution to the 3x00 swap problem.
Most people just modify one of the stock 2.8 brackets, however, I did test fit parts on a LX9 oil pan, and they do fit the same as they do on the LZ4 pan I have, with the exception of the taller vertical part, the LZx version is too short for the older engines.

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Shaun41178(2)
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by Shaun41178(2) »

Small spring upgrade I. Progress. This is a small upgrade over stock. Summit essentially says these are essentially a factory ls6 spring when it comes to spring rate. I verified the wire is slightly thicker than stock and the uncompressed height is a smidge higher than factory. This should add up to a slightly higher spring rate than factory any chance of valve float on a lnj cam should be eliminated
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ericjon262
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by ericjon262 »

have you had a chance to test fit the engine to the cradle with that mount?
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Shaun41178(2)
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by Shaun41178(2) »

Not yet
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Shaun41178(2)
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by Shaun41178(2) »

Progress has been slower than slow but I got some work done the last couple of days. The front of the engine is back on, timing cover, new waterpump, and the coolant crossover at the heads as well as the lower manifold.

I also painted the firewall side vc white, not sure if I'll install it but I wanted to see what it looked like.
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by Shaun41178(2) »

Valve cover.
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eHoward
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by eHoward »

We did a bit of a test fit a week ago. The mount is pretty close.

Eric, we might be able to slot things and make it work but it looks like we would want to move it over ~10mm-11mm ideally so it goes in without slots. Note the setup has wcf mounts that located fine with the stock mount.

Appreciate all your effort to make this thing.
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ericjon262
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by ericjon262 »

Thanks for the follow up, I'll have to make some revisions. I think slots might be the smart answer, to allow for some adjustability for transmission placement. I'm been extremely busy working on my house, and haven't had much time to do many of the things I would like to do, like work on these and the dogbone brackets, maybe sometime after next week I'll be able to take some time to nail some stuff down a bit better.
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eHoward
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by eHoward »

Thanks!
eHoward
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Re: Lz9 + 4 spd manual trans in 86 GT swap

Post by eHoward »

Thanks!
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