'87 Fiero LZ9 swap (Page 1/8)
TheMoist1 DEC 30, 10:24 PM
I started a thread about this on 60degeev6, but I'm going to start posting here also starting now. What I plan on doing is swapping a LZ9 (Technically a LGD) from a 2007 chevy uplander into my 1987 Fiero GT. I'm going to use a MegaSquirt3 Pro Mini as the ECU. I chose this ECU over the MicroSquirt even though its more expensive because it can run sequential injection, where the Micro can only do batch injection. I tore the LZ9 down to the shortblock, and removed the old VVT cam. I replaced it with a 3.4 LNJ cam from a 2007 Equinox. The LNJ cam is still a stock cam so shouldn't be any more power over the VVT cam but this is the only cam that I know of with the same bearing journal size that is not a VVT cam. The other option would be to run bearing spacers and use a cam from any other 60 degree v6. Either way this keeps things simpler for now. I got it timed Using a 3.4 timing set, and a LZ9 tensioner. I covered it using the 2.8 timing cover and water pump I already had. I used the LZ9 timing cover gasket for this which caused a slight problem I found out about later. Originally, there was a coolant crossover connecting the heads on the front side of the engine. I plan on mounting the dog bone there, so that had to go. The solution to this is to flip the heads and head gaskets around so the coolant flows out the back. I made some blocks that cover the outlets, and adapt it to -12 AN fittings. I'm going to use the stock LZ9 manifolds, and route them in a similar way to the way the Fiero was routed from factory. Of course the manifolds aren't meant to fit in this car, so some modification was needed for the rear manifold. It originally has a crossover that connects the front manifold to the rear, and a flange on the rear manifold is the exit for all 6 cylinders. because of this the rear manifold has all the ports pointing toward this flange, so I cut out a section and welded in a straighter section so it might flow better. For the intake manifold, I'm going to use a LZ4 manifold. It will bolt up to the LIM on the LZ9, but it deletes the variable intake runner. I did not want to use the LZ9's electronic throttle body, so I found a LS4 to 3 bolt throttle body adapter, which mostly fits to the LZ4 manifold. The 4 holes that mount to the manifold didn't line up perfect so they were ground down a bit to fit. the intake hole also wasn't concentric with the manifold hole. so I ground down a bit to make a better transition for it. The throttle cable cam was pointing at a weird angle for the throttle cable to go, so I took it off and welded it back in 90 degrees from where it was. When I got the crank and water pump pully in, I realized the problem that the LZ9 timing cover gasket caused. The gasket spaced the cover and water pump off just enough that the pulleys didn't line up anymore. The solution I ran with was cut a spacer the same thickness for the crank pully. I got the engine bolted to the transmission, and tested the 2.8 engine mount. it will bolt to the engine, but with only one bolt. The oil pan on the LZ9 also runs in to the forward stud on the mount. I cut away the part of the oil pan that was interfering, and modified the engine mount to tie in to the oil pan. That's where I'm at so far! I'm going to put the modified mount on when the paint dries.


LNJ camshaft


Heads are flipped

Coolant block I made with -12 AN fittings



Rear exhaust manifold modification

LS4 TB adapter

Modification inside intake hole

Throttle cam modification



Pulleys are offset

The crank pully spacer

Pulleys are fixed!

Engine in cradle thanks to Mr. Hoist

Oil pan shaved where it interfered with engine mount stud

Modified Fiero engine mount for the LZ9
Raydar DEC 31, 10:11 AM
That's some nice work!
I'd like to do an LZ9 at some point, but I'm thinking about the cam bearing spacers, and a fat cam.
Being that you're using the Megasquirt, I'd be tempted to keep the VVT, and make the accessories work in the Fiero. (The Megasquirt will run the VVT... right?)
TheMoist1 DEC 31, 10:22 AM

quote
Originally posted by Raydar:

That's some nice work!
I'd like to do an LZ9 at some point, but I'm thinking about the cam bearing spacers, and a fat cam.
Being that you're using the Megasquirt, I'd be tempted to keep the VVT, and make the accessories work in the Fiero. (The Megasquirt will run the VVT... right?)



Thanks! Yes from what I've seen the megasquirt can run VVT. I'm planning on putting in a bigger cam at some point. Either bearing spacers or try to regrind this Equinox cam.
Raydar DEC 31, 02:04 PM

quote
Originally posted by TheMoist1:
...
I'm planning on putting in a bigger cam at some point. Either bearing spacers or try to regrind this Equinox cam.



I'm not sure about the Equinox cam, but I've heard that many of the V6-60 roller cams are hollow, and pressed together. (Sounds kinda sketchy to me, but...)
Point being, I'm not sure it can be reground.

There is a 60 degree V6 group on Farcebook. Lots of knowledge, there.


Please keep us updated on your build/swap.

[This message has been edited by Raydar (edited 12-31-2024).]

TheMoist1 DEC 31, 02:29 PM

quote
Originally posted by Raydar:

[QUOTE]Originally posted by TheMoist1:
...
I'm planning on putting in a bigger cam at some point. Either bearing spacers or try to regrind this Equinox cam.



I'm not sure about the Equinox cam, but I've heard that many of the V6-60 roller cams are hollow, and pressed together. (Sounds kinda sketchy to me, but...)
Point being, I'm not sure it can be reground.

There is a 60 degree V6 group on Farcebook. Lots of knowledge, there.


Please keep us updated on your build/swap.

[/QUOTE]

Yeah the Equinox cam is hollow. I don't exactly know the requirements for regrinding cams but if being hollow excludes it then I'll probably just go with spacers or something similar.

[This message has been edited by TheMoist1 (edited 12-31-2024).]

Raydar DEC 31, 03:07 PM

quote
Originally posted by TheMoist1:


Yeah the Equinox cam is hollow. I don't exactly know the requierments for regrinding cams but if being hollow excludes it then I'll probably just go with spacers or something similar.



Delta is probably the leader in regrinding cams. At least they're the ones I most frequently hear about. But, from the looks of things, you probably already are familiar with them. I would give them a shout and ask.

Anyway, it looks like you've got this well in hand. I'll just kick back and applaud your progress.

[This message has been edited by Raydar (edited 12-31-2024).]

TheMoist1 DEC 31, 08:19 PM
Engine mount doing it's job now!
Dennis LaGrua JAN 01, 06:09 AM
Nice swap and excellent work. IMO that 3900 engine should make 300+ HP

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

TheMoist1 JAN 01, 07:53 PM
Got the crossover tacked in place. It's using the majority of the original LZ9 crossover on the back side, and merging about where the Fiero originally did. The crossover is 2" and merges to 2.5". It has a V band clamp on the end.
ericjon262 JAN 02, 05:37 PM
I feel like ditching the stock accessory drive is kinda odd, I definitely prefer all the stock 60V6 serpentine drives to the stock fiero mess.

Nice job on the mount, simple, and effective.

------------------
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

I invited Lou Dias to trash me in my own thread, he refused. sorry. if he trashes your thread going after me. I tried.