World's slowest Fiero/Quad 4 Swap (Page 1/28)
Quad Raider JUL 15, 09:17 PM
I've always planned to post a thread about my engine swap, but figured I'd do it once the swap was complete and the car was on the road. But since it's taking so long, I decided to go ahead and start the thread in spite of all the work I have left to do.

The other reason for starting the thread now is to hopefully break the curse that's befallen my family's cars. As I've posted in other threads, every time I make significant headway on the Fiero, something goes wrong with one of the other cars in the family. Most recently my wife's 2002 Grand Prix GTP 40th Anniversary edition suddenly needed transmission work, then on Monday she hit a deer, or more precisely the deer hit her car, causing major damage.

Here's the donor:

My brother bought this 1992 Quasar Blue Beretta GTZ in 2007 in St. Louis. I went up there with him to look at it then drove his truck home after he bought it. It had the H.O. Quad in it, which I believe is the second most powerful Quad GM offered, after the W41 version sold in the Olds 442 (the Quad is an Oldsmobile engine, after all).

Roger drove the GTZ for about six months and then it blew a head gasket. He gave it to me and I fixed the HG and made some other repairs and then drove it every day for four years. I work in downtown Tulsa and my commute is about 30 miles each way. I fell in love with that car. So much power but I'd get 30+ mpg on the highway. The AC didn't work, the suspension was worn out and the sunroof leaked, but damn it was fun to drive, especially up an on ramp.

Some time near the end of those 4 years, I got into the car to leave work and the seat fell over backwards. When I pulled up the carpet to see what the problem was, I was stunned to see a giant rust hole. I welded in some replacement steel and eventually tried replacing the whole driver's side floor pan, but the rust was just too much, so I started looking around for a replacement. I wanted another GTZ but couldn't find one in at least decent shape. Then one morning on the drive to work I saw a Fiero heading the opposite direction. I asked my brother Roger about swapping the engine/transmission from the GTZ into a Fiero and he loved the idea. He had owned two Fiero GTs and a couple other GTZs over the years and knew instantly what a great combo they'd be.

I found a 1987 Coupe in Fayetteville, Arkansas and we went to look at it on New Year's Day 2011. The original owner was selling it because it had quit the previous October and she just didn't want to deal with it anymore. She still loved the car but was ready for something else. On the way over to look at it, we passed through the town of Cincinnati, Arkansas where a tornado had hit the night before. Maybe that was a signal that things wouldn't go as planned.

Two weeks later we went back to pick up the car and bring it home. The plan was to paint the car and make the modifications I wanted, then put the GTZ engine and transmission in it. I thought it would take about 6 months, total. Nine months later, my Quad's timing chain tensioner broke and the engine chewed up its timing gears and bent four valves, so that was the first major change in the plan.

The biggest problem was the sudden loss of my brother last August. He died of sudden cardiac arrest. It's been hard, at times, to work on the car since then, but I know he would want me to finish it and I'm determined to do so.

So here's what I've done to the car:
-rebuilt headlight motors
-repaired broken headlight door frame
-repaired broken horn buttons
-fabricated under-spare battery tray
-fabricated Quad 4/Getrag mounts
-modified cradle to fit Quad 4
-installed solid cradle mounts
-shortened rear tie rods 3"/moved mounts
-converted to sunroof
-disassembled Quad
-obtained/painted GTZ wheels
-fabricated custom center wheel caps

I will post more photos. Right now I have them saved on three or four different devices but now that I've started this thread it will be easier to collect and post them.

Right now the body panels are off the car and I'm sanding and priming them. More on that soon.

Over the 6 and 1/2 years, here are the extra items I've collected:
-two doors with power windows and locks
-two power window/lock wiring harnesses
-three sets of seats
-three sets of sail panels
-two extra front fascias
-'88 rear fascia
-'88 deck lid with wing
-'88 cradle and rear suspension
-two extra Quad 4s
-extra Getrag

[This message has been edited by Quad Raider (edited 07-15-2017).]

Quad Raider JUL 15, 09:20 PM
Here are the two cars together shortly after we got the Fiero back to Oologah.

There was a stick of firewood propped under the right headlight. The paint and interior were rough but the car was almost 100% complete, and it was a 5-speed so I bought it.

[This message has been edited by Quad Raider (edited 06-27-2018).]

bjm362 JUL 15, 09:33 PM
Glad to see a post not to far from my neck of the woods! I used to go swimming up by Oolagah!!!
BTW, nice find. I need to get lucky and find a complete car in need of some attention to detail for the right price!!
sardonyx247 JUL 16, 08:37 AM
You would think it is the slowest quad4 swap, I was starting mine over a decade ago, I was going to go turbo.
But right as I was going to buy my forged pistons, my GT came for sale, and used the money for that. Then blew my engine on the way home, see my GT sitting there with no engine I went to "just quickly throw one in" and started with the whole 3.4 game, I just never quit with the GT. I had all the parts for the quad, plus many extras, but over 10 years later I got a quad drop out from Fierobssed (total thanks) and decide to finish it. Plus at the time there was no way to program the ECM as the whole turbo Idea, I got the quad forum, (when it first started) to bug tunerCAT non stop until they came out with the code, but by then I took my turbo knowledge and put it into my GT.

On the plus side, with all the info I gathered over the years I was able to assemble the biggest collection of Quad 4 info in one place anywhere on the net, right here on PFF.
And with the pallet of Quad parts I have, if you need something, let me know.

The Quad should have been the stock 4 cyl in the Fiero, to bad it didn't come out until after it's demise.

Good luck on the swap, yea another Quad 4 Fiero!!!!!

'84 Fiero, engine to be determined '87 Duke (Sold)
'87 Quad 4 H.O.
'87Blue GT 3.4L Swap Completed!!!!!!!! Boosted!!!!!!!
^^^^ Now in the Construction Zone^^^^
Las Vegas Fiero Club Parts/Sales/Service/Club
Fiero Road Club Of Northern Nevada
Now on my 11th Fiero

Quad Raider JUL 16, 09:14 AM

Originally posted by sardonyx247:

On the plus side, with all the info I gathered over the years I was able to assemble the biggest collection of Quad 4 info in one place anywhere on the net, right here on PFF.
And with the pallet of Quad parts I have, if you need something, let me know.

The Quad should have been the stock 4 cyl in the Fiero, to bad it didn't come out until after it's demise.

Good luck on the swap, yea another Quad 4 Fiero!!!!!

Thank you. I've used your thread for reference a lot already.

A couple years ago I accidentally deleted all the photos on my phone. They included all the pictures I took while disassembling the car. I had saved some of them along the way for various reasons so I'll share what I have, but reassambly will be more challenging.
Lunatic JUL 16, 07:56 PM
If you were closer, I'd certainly lend you a hand working on this Quad 4 swap. On another forum, there's a guy selling a Quad 4 Fiero for cheap. Road trip with a trailer?
Check it out here.
Quad Raider JUL 16, 10:44 PM
Thanks, Lunatic. I know from reading your thread you do great work.
Quad Raider JUL 17, 08:25 PM
I'm having trouble tracking down photos of some of the work I've already done. For instance, I can't find the pictures I took while I was mating the Quad to the Fiero's cradle. They're probably on one of my old phones. (side note: One of the many lessons I've learned on this build: use one device for taking and storing photos during a project).

Since the HO Quad from my GTZ is disassembled, I used one of my spare quads to fabricate the engine and transmission mounts. Early on my plan was to rebuild my HO and install it in the car, THEN do the bodywork and paint and finish the interior. That changed because I started buying body and other parts and the shop was so cramped it was difficult to get anything done. Plus, I came across a sunroof car in the salvage yard and this forum convinced me to switch over (what a huge load of work that was, since I had to rebuild the first sunroof panel I bought because I broke the A pillars getting it off the donor car). So I switched gears, deciding to do the body work and get the panels installed on the car, then worry about the engine and the rest of the mechanical work.

Right now the engine and transmission mounts are just roughed in. I need to weld in some extra bracing and paint them, so I'll post photos once I'm done with the body work and pull the cradle out again.

This is one of my spare Quads sitting in the car. As you can see it fits great, like it was meant to be there.

Notice that the exhaust side of the Quad is to the back of the car. This is important for another reason.

Moving the battery to the front of the car really helps open space.

I was very careful when fabricating the mounts to make sure I'd have room to close the deck lid without having to modify it. Some owners have had to cut away part of the deck lid frame because the Quad is so much taller than the Duke. There's a sweet spot where the crank pulley sits about 3/4" above the cradle and the top of the engine clears the deck lid by about a quarter of an inch. Again, pictures of this step to come later.

The AC compressor on the Quad sits much lower than on the Duke, so the exhaust hump has to be modified. Some owners just cut a small part off the arch, but I decided to remove it altogether since there's no reason for it with a Quad.

I used some scrap 3" square tubing. I wish I'd taken more photos of the process.

Right now I'm sanding and priming the body. More on that in a future post.
Quad Raider JUL 18, 08:08 PM
Here are some more photos of how the engine fits in the car.

As I mentioned, it's possible to get the engine and trans to fit without having to modify the decklid.

It's been so long since I did the work, I'd forgotten how well everything fits.

I got to this point by putting the cradle on my heavy duty welding table, then lowering the Quad/Getrag onto it. Unfortunately, the photos I took of the process were some of the ones I accidentally deleted. I used blocks of wood and a level to get the engine to sit where I wanted, then fabricated the mounts to fit.

There were two basic engine mount designs for factory Quads. The Grand Am type has a mount on the intake side and one on the exhaust side. The GTZ type is similar to the Iron Duke type, with a u-shaped flange around the oil pan that sits on a big rubber mount bolted to a plate. At first I was planning to convert to the Grand Am type, mostly because that was the kind I found in other swaps. After I cut the flange off my cradle I realized how similar the Duke/GTZ mounts were and changed my mind (a common theme in this swap), so I had to weld in a new flange. It worked out OK because that made it possible to put the flange where I wanted it.

I decided I didn't want the oil pan to be flush with the bottom of the cradle, so I used a piece of 1/4" plywood to raise it up a bit.

There is some surface rust on my welds because the Fiero had to spend some time outdoors due to the aforementioned major repairs to other cars in the family. Once I'm done with the painting and have reassembled the body, I will pull the engine and cradle and take care of all of this.

Here's the AC bracket on the Quad. You can see how low it sits on the engine, requiring modification of the exhaust hump.

These pictures show how I shortened the tie rods by 3". I found several pages on the internet discussing the poor geometry of the design and the recommendation to move the pivots at least 2" toward the outside. I had the time so I decided to go 3". Discovering whether this was a good idea is one of the great mysteries I hope to solve by finishing the swap.

One cool feature of this swap is that the Fiero axles fit the Quad's Getrag. These photos also show how I converted to solid mounts on the cradle. I cut a short section of pipe and welded it onto the cradle.

sardonyx247 JUL 19, 08:09 AM
I used the hump in the cradle to run my coolant pipe under it. Fits perfect in the hump.