My LSX swap - 1991 Z28 convertible

[91t/a]

wow that engine is perdy!

[BlueZee28]

Thanks guys.

I love it when the UPS/FedEx man comes, it's like Christmas haha.


I got some of the parts I ordered over the weekend today. And I got the wiring harness in as well, so I have a bit of things to work on this weekend now.

I decided to make my own fuel lines, so these Russell Performance fittings are going to be put to good use. I'm still waiting on two other fittings that are back-ordered at Summit though.



This looks like fun haha

[CamaroSpike23]

Nick, I'm sure you checked, but I just wanted to make sure that you verified those LT's will work with this swap. I know there are only a few companies that make LT's that will work in these swaps

[brandotron]

Goddamn, that's awesome man! You're making me miss my Formy 350!

[BlueZee28]

Originally Posted by CamaroSpike23

Nick, I'm sure you checked, but I just wanted to make sure that you verified those LT's will work with this swap. I know there are only a few companies that make LT's that will work in these swaps

These are the Stainless Steel Works, the headers that Hawks sells specifically for LS1 swaps in 3rd gens.

[Iroc-z86]

Very nice build man, keep it up!

[Super83Z]

You sir are my hero. I started building my 83 right before the LS1 craze. Althought I love the small block 406 I got, Ls1's and thirdgens are awesome.

[BlueZee28]

Haha thanks! Yea, it's a craze that doesn't seem to go away here in St Louis. We've got LSX swapped 240SX's, RX7's, Caprice's, 3rd gens, Fox bodies, S10's, '69 Camaro's, you name it, it probably has an LS1 swap around here.

I'm joining the ranks of the 3rd gen LSX posse haha. We've got at least 5 other ones in my area that I can think of off the top of my head.

[Zabo]

Originally Posted by BlueZee28

This looks like fun haha

I take it that's just the harness for the engine, correct? Still keeping the ECU from the Pickup or did you have the ECU on the '91 modded to accept the harness?

Nonetheless, I can't wait for the day this thing is finally fired up and lays a patch.

[BlueZee28]

Ya the harness on the left is the engine harness from the '91 which was cut down to about 8 or 9 wires I will use. The one on the right is from a 2000 LS1 fbody and was re-pinned to accept the 3rd gen wires I am using. The computer will be from a 2000 fbody.

[Supercamaro64]

hey man tht looks awesome!!! it looks a lot like the swap me and som friends did with his Nissan 300zx. altho we put it in and took it out about 10 times before we finally got it rite lol, good job!!! its so much fun puttin an engine in (espiecially wen u get it started lol)

[BlueZee28]

More progress and mods.


The UPS man dropped off my LS6 intake, which I promptly installed on the motor after removing the regular LS1 manifold. While I had the intake off the car I also put on the knock sensor wires which I had forgotten to do previously. Then I bent the coolant bypass tubes downwards just a hair, and took a sander to the bottom of the intake manifold so that it would clear the LS1 coolant bypass tubes. I should have gotten an LS6 valley cover and bypass tubes, but alas, it satisfies the need.




I also took the modified LS1 harness out of the box today and began plugging things in. My first impression was that this is going to be easy. After a few minutes of plugging stuff in and pulling back the loom to read the marked tape on the wires so I could figure out where they go, I got it down to this. The only things NOT plugged in now are the a/c wiring, o2's, trans wires, the red mass of wiring that will go to the 3rd gen harness, and the wiring that will feed down into the fender and under the dash to plug into the computer. Ok, well there's a few more wires still not connected to anything, but those are just a few things I need to figure out what they go to first, but the majority of the harness is hooked up and ready to roll. I also got the starter I picked up last week installed on the block, which I wasn't thinking when I put that on before hooking up the crankshaft position sensor. That was fun lol. I'm thinking I will get a set of fuel rail covers by the time this thing is running too. I would love to paint a set to match the body color of the car.












I also picked up one of the last pieces to the puzzle today, a red top Optima for $110.

[BlueZee28]

More progress.


First off, I have somewhat of a unique item to share with those of you who are using the 4th gen coolant reservoir on a 3rd gen Fbody. When you cut the hole in the battery tray to make room for the bottom end of the 4th gen bottle, you will notice that there is a brace for the passenger side fender that is in the way, and it will not let the coolant bottle rest correctly against the battery tray. Removing the brace will allow the fender to flab in the wind when you're going down the highway. So, it is important that you somehow utilize this brace, and my dad and I came up with an easy solution to do just that. There is a small hole in the passenger frame rail, just a little ways backwards from where this brace would normally mount. I decided to use that hole to mount the brace because it allowed just enough room for the coolant bottle to sit properly. To do this, I took a sharpie and marked how short I needed to make the brace, then put it in a vice and bent it at a 90* angle, drilled another hole in it and got a bolt and locking nut to fasten it in place in the new hole. You can see from these pictures exactly where I decided to mount it, and I took a picture from below the fender to show how much clearance it gave me with the coolant bottle. In the 3rd picture, my index finger points to where the brace mounted from the factory, so you can see how it poses a problem when using this coolant bottle.









The other big part of my progress from today was cutting the hole for the manual shifter. I cut it just within the stock holes for mounting the auto shifter (there are four holes). The carpet on the driver side hangs over a little bit so you can't see all four edges of the hole, but you get the idea.



Then here is something I was really excited to get out of the way. I went ahead and undercoated just the transmission tunnel, all the way back to about 6" behind where the shifter will be. I also undercoated up into the engine bay just a little bit. I wanted to get the tunnel done so I can get the motor and trans in next weekend. I'll undercoat the rest of the car once it is running and I can take it up to my friend's work and use their lift, because doing it all on your back with the car 2' off the ground kind of sucks.




More of the undercoating. I made a fine line between blue and black on the trans tunnel, I think I like it this way with it coming into the frame rail in the engine bay. What do you guys think?

[BlueZee28]

Ok so I got a CRAP ton of stuff done last night thanks to my bad case of senior-itis ( skipped my last class last night haha ).


I got to work on the fuel lines tonight since my last fitting came in from Summit the other day. This is the saginaw fitting that goes on the hard feed line coming from the stock sending unit.



I had to use some imagination to get the fuel filter mounted. With the extra fittings coming off both ends, it made the unit way too long to mount in the stock position (which you can see where the stock one mounted in this picture, in the bottom right corner of the photo). I drilled a hole and put a self-tapping screw in to hold the filter here. I had to mount it vertically instead of horizontally like the stock one. This allowed me to also use the stock rubber line that is used for the return that would have gone into a hard return line. Instead, the rubber line goes into a Russel fitting then straight to the Corvette filter. I'll have more pictures of the fuel lines once I get the motor and transmission in the car this weekend. I didn't want to mess with the feed line coming from the filter because I don't know exactly how long it will be just yet.






This next piece also took some creativity. As you know from some previous posts, I am using 4th gen coolant and washer tanks, which the washer tank mounts in the front bumper. Well on a 3rd gen there is a black brace that mounts from the front bumper to the brace for the hood latch. I didn't want to toss the piece away because I want to try and use every piece from the stock front end as possible to make it as sturdy as possible. But in order to use this brace it needed to be trimmed down some to clear the top of the washer tank. Here you can see where I made the cut.




And you can see how well it clears the washer tank now.






And for mounting the washer tank, yet again, I used my imagination. If you mount it flush against the frame, it hits the hood latch support brace. Ideally, you want to mount an inch or so off the frame so that it's not in a bind, or hitting the brace support. Some people have used a longer bolt and a piece of fuel line as a spacer to keep the tank off the frame a little bit. I took the black plastic trapezoid shaped piece that was used with the stock battery tray to mount the battery in place, and cut it in half, and ground it down smooth into two oval shaped piece. It was just thick enough to meet my satisfaction, so I drilled holes in the two pieces and mounted it just the way it is.