Well I'm looking to do an engine swap. So far the Quad-4 seems to best suit me.
Can someone please give me a rundown of what "interesting" things I will need to do to fit one?
It'll be going into an '88.
I understand the transmission will need to be swapped to, that's no problem.
Can anyone tell me about the engine mounts?
Also, what have others done for the exaust system?
Giving up my trunk for the exaust is NOT an option.

Here's another one for you, outside of the cost of the engine and tranny, how much would I be looking to spend in other parts (roughly)?

And finally, I'd like to hear from any Quad-4 owners on the forums, what you think of it and how well it performs.

I've not driven a Quad in a Fiero, but I've got the latest rendition of the Quad in my Cavalier (the 2.4L "Twin Cam").

Let me tell you, even the low-output 150 hp (155 ft-lbs@2500-4500) is a fireball of a little motor

and then you go and throw the GM supercharger kit on it for 190 + SC noise. WHEEEEE!

The older ones (2.3L) had a High Output version at 180 HP naturally aspirated, and they even had one hotter, the W41 at 190.

The HO runs 10:1 compression and W41 runs 11:1. LO is 9.5:1.

www.j-body.org has quite a bit of tuning information for it
http://www.the-race-shop.com/ has a lot of information and options
http://www.jbodyperformance.com/new/newIndex.php can custom grind cams and does head work on Quads, and a the other motors found in Cavs.

They're one of GM's spin-happy motors, but still surprisingly torquey

If you haven't noticed, I'm a fan They're an iron block w/ aluminum heads, and they've been around long enough to have OBD1 versions - the 2.3 HO and W41 are obd1s.

Be careful that you don't get the SOHC version, that one has problems, and the head doesn't flow very well.

I know of a couple of people here on PFF who have done this swap, and they seem to be happy with it. https://www.fiero.nl/forum/Forum2/HTML/060778.html "400 HP quad4 buildup - revisited" should give you some good info as well.

All very good info above. I love the HO in my dads Grand Am. Thing to watch out for is the head, it has a bad tendancy to crack around 100k miles and needs to be replaced when it does.

I've been worried about head cracking after all I've read...
It seems the later years improved on this slightly, but so far I havent seen Anyone running one of the later years of Quad-4 in a Fiero. Is there any reason why not?
I'm pretty sure I can get my hands on a 2001 Twin Cam and transmission, but I'm slightly worried by the fact that everyone else has passed them up in favor of an older one.
I dont need to squeeze an extra 5 HP out of the thing at the expense of cracking heads and blowing head gaskets all the time. The 170hp of the 2001 is plenty.
Dont forget that I'm moving up from a Duke, and want decent gas mileage too.

There was a member here who had done both a 3.4l DOHC and Quad 4 HO swap.

Not to discourage you, I think the Q4HO is a great platform for a good turbo system, and would be pretty sweet in the Fiero. Not to mention I think it'd fit the Fiero's personality well.

But according to the member that did both, and I hate to say it but I forgot his s/n, he said there is no logic behind doing the Quad. It is more expensive, harder to swap, less powerful, less torque, less reliable, and its weight advantage isn't noticable according to him. But if you are going for a lightweight race car, I think it could be a perfect platform. But for the majority of Fieros, I think the 3.4 is a better option.

Check out Bryson's build thread, he made 400whp on his turbo quad, before some unfortunate events. But from what I ehar he is rebuilding it bigger and better, so keep an eye out for that!

------------------

"all pushrod motor are better than the dohc because it has less rotational mass"
-rick17, MyMonte member, owner of a 3100 Monte Carlo LS

I realize this goes against the grain somewhat for Fiero engine swaps...
But I dont need an utter ton of power. I dont Want 400 HP. I dont even want 250.
The 170 HP of the Quad-4 is a nice improvement over an anemic Iron Duke, but doesnt sacrifice good gas mileage.
And the reliability of the later Twin Cams seems pretty good, though I'm not too happy about it being an interference engine.
What's more, it looks easier than plenty of swaps I have seen. I'm perfectly fine with the electrical work, the transmission plops in nicely, the only difficult things it really seems to need is some exaust work and new engine mounts welded in.

The 2001 Cavalier is listed at 2617lbs, 21/28 mpg so I would think it reasonable to expect the same performance characteristics with the engine placed in the fiero I think the power rating was 150/155 either way it has a lot more power to offer than the 2.5 as it is. I'm not sure there will be a big difference between the engines in weight outside of the cylinder head, GM may have lightened the block a little and I don't think I would worry to much about the cylinder head given the history of the 2.5s cylinder head.

[This message has been edited by Joseph Upson (edited 12-16-2005).]

I was going by 2001 Grand Am specs, which shows a 3200 pound car getting 32 MPG on the highway. This engine provides 170 HP.
34-36 MPG in a 2600 pound Fiero shouldnt be out of the question if I'm easy on it most of the time and remove a bit of exaust restriction and such.

I get about 33 mpg crusing at 75 mph on my 175 HP 2.3. I've heard others as high as 38 mpg.

Be careful with your expectations, the sources sometimes vary considerably in what the actual specs are especially when it comes to miles per gallon depending on who's providing them (talking about data bases not members). There is a chevy high performance or hot rod magazine that printed an excellent multi page write up on the differences between some of the Quad 4s from heads and exhaust to the balancing shafts and the pluses and minuses regarding building a performer. I believe it was somewhere in a 2000 edition, unfortunately I have it at another location which can't be of any use to you at the moment. You maybe able to find it if you do a search on either of those their sites.

[This message has been edited by Joseph Upson (edited 12-16-2005).]

This could be the Hot Rod article you were thinking of: http://hotrod.com/techarticles/73858/

That's it

Another site to try is:

http://www.quad4forums.com

I have a 1990 Quad 4 HO with a 5-speed in my 86 Fiero Coupe. I got 38MPG (Canadian) doing 70MPH plus on a highway for several hours, which included downshifting into 3rd to pass.

The hard parts of the swap were the engine mounts and wiring. The engine has no dogbone, but 2 engine mounts. The transmission for the 2.3L from 87-94 was a 282 Getrac, 95 and up 2.3L and 2.4L use Isuzu units, but all 93+ transmissions use a hydraulic release bearing, which will complicate the swap. If you already have a 5 speed duke, then the easiest way to use the getrac would be to get all the cables and stuff from a 5 speed getrac Fiero, including the clutch slave, if it is not the 93+ tranny. The exhaust on the Quad 4 exits on the opposite side from the Duke, so your exhaust will exiting on the trunk side of the head, therefore it will be quite short, but the intake will be on the side where all the wiring is.

My Quad 4 has about 200,000miles on it and it still runs good. I am rebuilding it right now to get some better performance out of it, and I want to check it out before I go hard on it. But I still beat a stock 1992 Grand Am 4-door with 1/3 the mileage and the exact same drivetrain combination, and also a mid 90's 5.0L Thunderbird with a cam and exhaust.

As for power outputs, the best years for stock HP was the 89-92 years, they had 180HP/160lb/ft stock for the HO, 93-94HO's had 170HP The Rare W41 model from 89-91 had 190HP and 160lb/ft. LO's ranged from 150-160HP/155lb/ft in 2.3L trim, and the SOHC version was 110HP/130lb/ft. The 2.4L 'TwinCam' was 150HP/155lb/ft torque.

------------------

84 Fiero Sport Coupe #1192 :: 86 Fiero Base Coupe Quad 4 :: 84 Chevette CS 4 Door

I'm quite good electricly, so I dont think the wiring will stop me.

The exaust however, I'm not so sure of. I'd like to see some pictures of how people have run theirs. Keep in mind I dont want to turbocharge this thing (not any time soon anyway) and that giving up a portion of the trunk isnt an option.
In fact, just because I'm crazy, I'm trying to see if I can ENLARGE the trunk a bit after this swap.
Anyone got some suggestions there? Fairly free flowing would be nice, but not massivly loud. I'm not trying to make it sound like a honda eather.
Plus here in Vancouver I have the feeling I'll still need a cat to be road legal.

With the Twin Cam engines having isuzu transmissions, would it be worth snatching the getrag off of an earlier one?
From what I've seen, the Getrag on the Quad-4 is damn strong internally. But how are the later isuzus compared to it?

Here is my exhaust setup. The only thing I added was a resonated monza style exhaust tip. The pipe is 2.25" mandrel bent.

Got a sound clip of that thing running?
I dont think that would pass emissions around here, but it's a start.
Also, dont those things only last so long before they become little more than a straight pipe?

quote Originally posted by Jax184: Also, dont those things only last so long before they become little more than a straight pipe?

Correct. I have two on my 3.4 DOHC. They don't do much, after 2,000 miles on the 3.4 DOHC. But damn it sounds nice.

A copy of some things I wrote about the subject some time ago:

quote Originally posted by Fierobsessed: I think the 3.4 DOHC is better in most aspects. The swap is MUCH easier. The engine has more potential due to the fact that it really is just a Quad 4 with two more cylenders. But it is totally based on the 2.8-3.1-3.4 engines. The heads are much much less likley to crack. The engine itself weighs in at a hefty 420 lbs last I checked. It loves to pull to 6,000 and has lots of power and the personality fits the car. The aftermarket is very limited for it. The way the engine is set up, I think that all it needs is a good set of cams to get 300 horses out of it. Afterall the lift and duration are quite poor when compared to the Quad 4 HO W41, Yet the engine uses very simular valve train. And the heads are WAY better. So I think the potential for alot of NA horsepower is there, if you want to spend the money. If you REALLY want to spend the money, Go turbo it. The Quad 4 is a light engine, weighs about the same as an Iron duke and puts out an Impressive 180 horses. Its more of a high rev ver, Its good up to 7,000. A good Quad 4 HO will get outstanding gas mileage and take all the beating you can give it for extreem periods of time. A bad Quad 4 will blow a head gasket after a few beatings. The key thing to look for in a Quad 4 is one that doesn't get detonation even with 89 octane gas. If it doesn't ping then It shouldn't have a bad headgasket or too badly a cracked head. Almost all Quad 4 HO's have combustion chamber cracks, its just a fact. But when the crack gets too bad, it will detonate that cylender till the head gasket blows. The powerband of the Quad 4 is slightly higher then the 3.4 DOHC. Again, other then Mantapart the aftermarket is limited. Both of these engines IMO, should ALWAYS have a manual transmission behind them. Im hardcore both engines. The Quad4 is about 330 lbs and so is an Iron duke, The 2.8 is close to 400 and the 3.4 DOHC is about 420. (a crate motor with the crate weighs 446 so Im just guessing) I dont think my 3.4 DOHC put out a heck of alot of power at 6000+ But was FAR better at 3500-5500. I could have brought it to 7,000 but It was pointless. Either way, It would boil the tires from here to next week. Too bad it was behind an automatic. Killed 3 trannies that way. When it all comes down to it. The Quad4 has 180 horses and weighs 70-100 lbs less then the 2.8. So in reality its horsepower goes alittle fruther, like as if your 2.8 suddenly had 190. but the 3.4 DOHC will weigh you down a couple of lbs. So you loose alittle of the gain, as if the 2.8 suddenly had 210, Depending on year of the 3.4 DOHC. The reason I say the 3.4 DOHC is so much easier to install, you only have to fab 1 bracket for a dogbone, and cut the right side decklid hinge down to clear the cam sprocket and cover. You still have to wire and all that other stuff. But with a Quad 4 you have to make your own custom brackets for every mount, customize the cradle, and there is no margin for space with the Quad 4. It almost touches the decklid and the cradle, and the frame all at the same time. Then you have to do the same work as far as the rest of the install goes. The Quad 4 also uses its own bell housing, so no Fiero transmissions anymore. You must get a FWD getrag conversion kit. Luckily Rodney Dickman has all those goodies www.mantapart.com is the only place I know of that has aftermarket for the Quad 4. But with some porting, W41 Spec (or sligtly better) cams, a less restrictive exhaust will net you almost the same peak horsepower as the 3.4 DOHC is stock. The reliability will still be good (unless you get one of those "bad" ones I mensioned earlier) and the gas mileage will be far superior as well as it being better for AutoX.

Any way, I thaught I would say what I felt about the two swaps, but obviously that is not the direction this thread is going...
But this is!


I think you might like to see this though... It's my car on the dyno.
http://videos.streetfire.net/player.aspx?fileid=95946304-BB98-48C9-B950-1C6C4D42024D

Very nice to see the video.
Your writeups are interesting, though I cant stress enough that I need a fairly reliable, efficiant little engine more than I need a near uncontrollable belching fuel guzzling monster behind me.
I Like my iron duke, especially the gas mileage and overall simplicity of it all. Now the Quad-4 is a fair bit more complex, but it still happily sips fuel down the highway. Plus as you said if I find one that's head is in good shape it should be quite reliable.
An engine that gets the mileage of a duke and puts out more power than the V6 seems ideal to me.

I was planning to use the Twin Cam's transmission instead of a Fiero's, especially after seeing the differences in component quality between them. I take it this means I dont need a FWD adapter? I realize I'll need to redo most of the mounts eather way.
I still want to know if I'm better off snagging a 5speed off an earlier Quad-4 instead of the one the late twin cames come with.

Fierobsessed, Have you got any photos of your setup in the car? I'm still slightly concerned about exaust layout...

Well, you heard how LOUD mine was on the dyno!

I don't have hardly anything for exhaust! A "Y" from the manifold to two 2.5" Catalytic converters, out the tips! TOO LOUD!

I couldn't figure out an exhaust system that would have a catalytic converter and a muffler and come out with stock GT dual tips

One tip, I could have done it. Two tips would take something either creative, destructive or restrictive. As it is now, the two cats make the trunk too hot. Its empty with no carpet. I will rebuild exhaust someday. Its too bad the exhaust comes out the wrong side of the engine!

Unfortunatly my car is in NY while I'm living in Las Vegas, I miss it.

Heres my buildup if you have not seen it already, https://www.fiero.nl/forum/Forum1/HTML/039415.html

3000!!!! I made it!

[This message has been edited by Fierobsessed (edited 12-17-2005).]

Yah that's right, it was you Fieroobsessed.

Sry I forgot your name, but it was you whom I was talking about

My exhaust is loud. I only got that glasspack because it was cheap and I knew it would fit in the tight location. Right now, the paint is 3/4 black from the heat. Coming back from Calgary, a few other Fiero drivers, noted that the front of my glasspack was glowing red under my car. I think that adding a vent to get air moving behind the engine will help alot.

I had a video of me on the highway, but it seemed to dissapear off the internet. but here is me racing for the 1st time:

[url =http://videos.streetfire.net/Player.aspx?fileid=0164FA1E-2CEE-42F8-B09B-43DC45683E87]Click here to see Video[/url]

Here is how I did a cat and a stock V-6 muffler:

Here is what a cradle looks like to take the OEM brackets and engine mounts:

If you have an Izuzu in your Fiero I think that you are in good shape using the Izuzu that came with the Twin Cam. Dimensionally the later Izuzu looks the same as the Fiero and I believe the Fiero drive axles will plug right in. I also believe the shift mechanism can be transferred from the Fiero Izuzu to the Twin Cam Izuzu so that the Fiero cables and shifter will work. The Twin Cam Izuzu I looked at had different bosses for the front transmission mount bracket but I think the Fiero bracket could be modified to work. One of the Alamo Area Fiero Owner wnats to do a Quad 4 witht he later model Izuzu. I've got the transaxle for that swap in my shop right now but it hasn't made it to the front of the line to work on it.

quote Originally posted by Jax184: And yet another one for you, what's the weight of a Quad-4?

Did anyone have the answer to this one? I'd like to know as well.
Thanks

Befarrer you talking about this video?

http://videos.streetfire.net/Player.aspx?fileid=004B754C-DF88-4FF9-AB2A-027223AE3C4F

[This message has been edited by XzotikGT (edited 04-01-2006).]