Page 3 of 4
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Thu Dec 14, 2023 7:13 pm
by jdv
This looks like an excellent solution to the 3x00 swap problem.
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Mon Dec 18, 2023 7:17 pm
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.
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.

Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sat Jan 06, 2024 3:49 pm
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

- IMG_20240106_154315845.jpg (3.5 MiB) Viewed 24763 times
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Tue Jan 09, 2024 3:11 am
by ericjon262
have you had a chance to test fit the engine to the cradle with that mount?
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Wed Jan 10, 2024 4:09 pm
by Shaun41178(2)
Not yet
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Wed Mar 13, 2024 11:30 pm
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.

- IMG_20240313_220644951.jpg (3.07 MiB) Viewed 22688 times
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Wed Mar 13, 2024 11:32 pm
by Shaun41178(2)
Valve cover.

- IMG_20240313_220700828.jpg (2.6 MiB) Viewed 22688 times
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Mon Apr 08, 2024 9:53 pm
by eHoward
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Thu Apr 11, 2024 11:01 pm
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.
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Mon Apr 15, 2024 5:49 pm
by eHoward
Thanks!
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Mon Apr 15, 2024 5:52 pm
by eHoward
Thanks!
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Thu May 16, 2024 11:19 am
by jdv
Shaun any chance of running a double roller timing set if you had a cam with the three bolt gear mount? Any progress?
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sat May 18, 2024 9:28 pm
by Shaun41178(2)
jdv wrote: ↑Thu May 16, 2024 11:19 am
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
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sun May 19, 2024 7:20 pm
by eHoward
Like a glove.

- IMG_2085.jpeg (3.75 MiB) Viewed 21443 times
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sun May 19, 2024 7:21 pm
by eHoward
Shaun drilled a few new bolt holes and we’re in.
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sun May 19, 2024 9:58 pm
by 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.
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sat Nov 02, 2024 9:09 pm
by 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.

- IMG_20241101_172636267.jpg (3.98 MiB) Viewed 18670 times
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Tue Nov 05, 2024 5:08 pm
by 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.

Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Sun Nov 10, 2024 10:46 am
by 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.
Re: Lz9 + 4 spd manual trans in 86 GT swap
Posted: Mon Nov 11, 2024 10:21 am
by 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.