Lz9 + 4 spd manual trans in 86 GT swap

[jdv]

This looks like an excellent solution to the 3x00 swap problem.

[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.

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.

[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]

have you had a chance to test fit the engine to the cradle with that mount?

[Shaun41178(2)]

Not yet

[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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[Shaun41178(2)]

Valve cover.

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[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]

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.

[eHoward]

Thanks!

[eHoward]

Thanks!

[jdv]

Shaun any chance of running a double roller timing set if you had a cam with the three bolt gear mount? Any progress?

[Shaun41178(2)]

Shaun any chance of running a double roller timing set if you had a cam with the three bolt gear mount? Any progress?

I haven't looked into a double roller tbh. I did verify that the 3 bolt pattern on the lnj cam, and the 3 bolt pattern on the stock 2.8 cam gear do not match up i was actually checking to see if the older set could work which would allow an older double roller to work. But that's a no go. The 3 bolt on the newer cams is closer to the center bore of the cam compared to the older flat tappet cams

No progress on the swap at this time but should pick up shortly

[eHoward]

Like a glove.

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[eHoward]

Shaun drilled a few new bolt holes and we’re in.

[ericjon262]

sorry I hadn't gotten a new prototype over, not going to lie, I kinda forgot about it, been juggling a bunch of stuff lately. I'll probably redraw the mount with slotted holes to make it at least a little adjustable.

[Shaun41178(2)]

Not that anyone cares but more modifications to Eric's mount were needed, just small ones, and we also incorporated the factory front bracket. It's bolted to the cradle now for the last time presumably. I have the belt routing configured, and I think we need somewhere around a 67inch belt.

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[zok15]

I couldn't get my decklid to close with the factory lift bracket height, and that alternator is sticking up pretty high. How large does the notch end up being?

For reference, my lift point has been cut down quite a lot here and I put a new slot in it, and the decklid is not even closed fully.

[Shaun41178(2)]

I don't run any left brackets on my engine unless it's going in or coming out I left this one on but it's easy to take off if need be.

I might be mistaken but don't the fastback decklid sit a bit higher than the notchbacks on the underside? I thought the bracing was different or something. It's not a big deal, it can be removed if need be

No idea how large the notch needs to be for the alternator. We aren't there yet.

[The Dark Side of Will]

The structure is the same between the two styles of decklid. The fastback decklid has a little more clearance in between the structural channels.

Notching the structure, especially with the OE springs still installed, results in the decklid bulging upward at the cut when it's closed and latched, due to tension from the springs.