Turbo for a Fiero

I'm looking for recommendations for a good turbo kit for my v6 Fiero that won't absolutely break the bank.

You need to spend some money on making the engine last - forged pistons etc, and an appropriate cam profile.

I built a 3.2 engine for mine in 1990 using a stroker crank from a 3.1, Ross Racing custom pistons, a custom cam and valve train, headwork etc. It put right on 300 bhp (140 was stock) was limited to 10 psi of boost (no IC used) and lasted 20 years. The kit was made by Miller Woods and the turbo was a high end IHI unit - the Calloway Corvettes used two of them.

Performance was pretty good - 0-60 4.5, 1/4 - 13.0.

I suggest that you not try to do that engine on the cheap - you'd probably regret it when it comes unglued.  My car was the equal on the highway of the early Supra turbos - neither could pull on the other.

PS - I beleive that Miller Woods became Design One but don't know what happened to them.

In reply to wspohn :

Does the trans need to be built to handle it? 

The standard 5 speed Muncie/Getrag on the kater cars is up to the job and better than the 4 speed, which had a lot of trouble with too much torque. Having said that I am not a drag racing type so didn't torture the driveline.

IIRC the automatics definitely required some mods/replacement.

If you go  far as I did I'd advise use of the same Centerforce dul friction clutch I used.

In reply to The2ndSonofToyman :

Which V6?  Is it the factory 2.8L V6?  

As I said, I used the factory 2.8 as a basis but used a longer stroke crank from a 3.1 (the 3.4 block wasn't available yet).

BTW, if you fail to spend an hour on the stock exhaust manifolds with a high speed grinder you are leaving around 12 bhp on the table (GM couldn't have been bother cleaning up their fast and sloppy welding job).

Have you considered grabbing a v6 from a supercharged Buick/Pontiac that's already build for boost then turbo that? 
 

My brain says that's a swap that's fairly straight forward but my fiero knowledge is limited. 

He's at work today so I'll provide some answers. 

The engine in question is a 2.8L that was built by the PO with forged internals and now displaces 3.1L. The build sheet that came with the car says it's 8.5:1 compression. Looking at the build sheet it should handle some moderate boost without spitting its guts all over the pavement. 

The car currently has the 5-speed installed. He also has a 4-speed and a spare 2.8L engine. 

In reply to wspohn :

The only real need for forged pistons is to give you a wider band for tuning.  The stock cast pistons are fine up to way too silly for the street amount of boost. 

   It's the ring gap that causes pistons to fail. If the standard clearance  of .004-.006 is used.  The rings expand from the heat of the boost until the ends  butt together.  At which point they tend to pry the ring land off which starts the failure cycle.    
       Use E85 and you can get really silly with the amount of boost  without hurting the stock engine.  
    But you will need to program your engine for it.    Bigger injectors and a sensor to give you flex fuel ability. 

1SlowVW said:

Have you considered grabbing a v6 from a supercharged Buick/Pontiac that's already build for boost then turbo that? 
 

My brain says that's a swap that's fairly straight forward but my fiero knowledge is limited. 

The Buick is a 90 degree engine while the 2.8 is a 60 degree engine.  The additional width of a 90 degree engine not only makes getting to the spark plugs tough  but may hit other parts of the car.  

In reply to The2ndSonofToyman :

If you have fabricating skills make your own kit.   The chinese turbo's are holding up very well and really are inexpensive. $130ish Amazon or EBsy. 
 If you plan on using flex fuel.  the use of pump E85 will eliminate the need for intercooler and save you all that complexity  and expense.   
  You can run around using pump premium as long as you keep the boost below 6 psi.  And when you want to push the car fill it up with E85. So you can run 12-15+ pounds of boost. 
    I don't know if your ECU  has programmable memory. If not a Megasquirt is a worthwhile addition. 

The only "cost effective" turbo kit is the one you spend a bunch of time (free?) to make yourself, with skills you may or may not possess, with equipment you may or may not own.

frenchyd said:

1SlowVW said:

Have you considered grabbing a v6 from a supercharged Buick/Pontiac that's already build for boost then turbo that? 
 

My brain says that's a swap that's fairly straight forward but my fiero knowledge is limited. 

The Buick is a 90 degree engine while the 2.8 is a 60 degree engine.  The additional width of a 90 degree engine not only makes getting to the spark plugs tough  but may hit other parts of the car.  

There is gobs of room in the engine bay on this thing. I'm trying to convince him to go this route with an LS4. 

Frenchy is right on the 90 deg. V6 - takes up more room.

Nothing wrong with the 60 deg. GM V6 except that the flow in the cast iron hed versions suck. A fully modded cast iron head flows about what an unmodified alloy head version does.   If I did one today I would opt for the larger bore 3.4 version or go for the slightly later alloy head 3400.

That Fiero gave me great service for over 20 years.  Shown here nose to nose with its successor, the 2009 Solstice GXP coupe (behind that the Lamborghini Islero S and Jensen Interceptor)

From the other end of the port cochere, a modded MGC and a Jensen CV8 with big block sixpack (non-stock).  Yes, I had too many cars!

3100 and 3800 family swaps are both common. Piston composition, design, and shape are equally important to a functional FI piston as ring gap. Yes some/many modern pistons are surprisingly tolerant of boost when they're not melted/cut in half by a ring but I'd guess that's not the case for a malaise era GM V6. 

The good/best/most efficient answer to your question involves googling "K Fiero" and slinging the ol' Discover card around a bit. 

If you're hell bent on turbocharging what you have make a crossover between the two exhaust manifolds containing your turbo flange and wastegate (honestly an adventurous muffler shop should be able to do this) sit the turbo above the trans. There's no kit but a basic turbo setup is probably fairly straightforward on this. 

Look at the things about fieros I'm learning today. 

Sounds like the motor should be capable of handling some boost, compression sure is low enough.  I would build a pipe joining the two exhaust manifolds and lead to somewhere there's room for a turbo, keeping in mind you need to get the air from the turbo to the intake manifold as well. Also keep in mind the turbo should be mounted high enough to drain the oil back to the sump or you need to run a pump to bring the oil back up.  Start on low boost and figure out engine management and fueling and then you're off to the races. As mentioned by Paul, it can be done quite cheap but you need to do the work. 

LS4 looks like a party.

I thought the supercharged 3800 Pontiac FWD motor/trans was the swap for a Fiero?  Tons of info on that on the 'ole webernet.  

https://www.youtube.com/results?search_query=supercharger+v6+fiero

Engine management and heat management will be things to consider. 

I'd imagine you can get an EPROM written that will handle boost and reference a wider map, but it will probably be easier long term to put a Megasquirt on.  My understanding is the Megasquirt 1/2 are built with a very similar architecture to the GM fuel injection setup used on these cars (I easily could be entirely wrong here as I am neither a MS expert nor a GM expert anymore).   

The on distributor ignition module did not like heat.   The turbo usually winds up near the distributor which increases the heat.  If you run an aftermarket ECU you could theoretically run coil near plug coils when you make the setup.  

I can't remember if this is an earlier fiero or 88.   If it's earlier better brakes should be pre turbo.   The OEM ones are just bad even with good pads.   GM parts bin options are readily available for cheap good vented discs and calipers that bolt to the stock uprights (IIRC it's all mid 90s FWD Grand Am stuff) and just require machining the integrated brake away on the front.  

A Fiero with ~200hp and the 60 degree V6 firing order noise would be pretty great and should be achievable with a lower boost setup.  I know the 60-v6 isn't a powerhouse but if you keep the goals realistic and don't push to hard it should be easier then a swap.   

Build thread is required.

SCed 3800?

In reply to nocones :

90s Grand Ams had the integrated caliper bracket, too.  Grand Am, Cavalier, Fiero, all same stuff IIRC.

preach (dudeist priest) said:

SCed 3800?

This is the answer, tons of kit car swaps around for the Fiero so you know it can be done. 

nocones said:

Engine management and heat management will be things to consider. 

I'd imagine you can get an EPROM written that will handle boost and reference a wider map, but it will probably be easier long term to put a Megasquirt on.  My understanding is the Megasquirt 1/2 are built with a very similar architecture to the GM fuel injection setup used on these cars (I easily could be entirely wrong here as I am neither a MS expert nor a GM expert anymore).   

The on distributor ignition module did not like heat.   The turbo usually winds up near the distributor which increases the heat.  If you run an aftermarket ECU you could theoretically run coil near plug coils when you make the setup.  

I can't remember if this is an earlier fiero or 88.   If it's earlier better brakes should be pre turbo.   The OEM ones are just bad even with good pads.   GM parts bin options are readily available for cheap good vented discs and calipers that bolt to the stock uprights (IIRC it's all mid 90s FWD Grand Am stuff) and just require machining the integrated brake away on the front.  

A Fiero with ~200hp and the 60 degree V6 firing order noise would be pretty great and should be achievable with a lower boost setup.  I know the 60-v6 isn't a powerhouse but if you keep the goals realistic and don't push to hard it should be easier then a swap.   

Build thread is required.

My reading on the coil on plugs replacement for a distributor is it requires more input than the regular Megasquirt has.   
       
  I do love the idea of getting away from the distributor. Because it makes tuning a breeze   ( key strokes on a laptop ) compared to a timing light and moving the distributor.  
  I think the stock heads on that 2.8 V6 also fit the Cadillac V6 of the same size and those are aluminum with much bigger valves. ( cheap). 

Gm made a factory turbo 3.1 for the early 90's grand prix turbo.  The turbo was mounted on top of the transmission, I think at that time the 3.1 was using a coil pack.

Some of the later splayed valve aluminum heads flow pretty good.  A supercharged 3800 would be easier though.  A ls4 would be cool too & probably the cheapest to build.

Caperix said:

Gm made a factory turbo 3.1 for the early 90's grand prix turbo.  The turbo was mounted on top of the transmission, I think at that time the 3.1 was using a coil pack.

Some of the later splayed valve aluminum heads flow pretty good.  A supercharged 3800 would be easier though.  A ls4 would be cool too & probably the cheapest to build.

The PROM for its computer (a '730, I think) was uploaded to the GM ECM site.  That, a PROM burner, and a crash course in tuning, and you're in junkyardable business from an engine controls standpoint.

If you can tune a modern standalone you can tune a GM ECM.  They tune the same way, you just can't do it real-time.  When I did MS3Pro swaps on older GMs, I would find a PROM image, load it into TunerCat (I think), copy and paste the tables into the MS, and away we go!

Megasquirt, BigStuff3, FAST, GM ECMs from the PROM era to the reflashable stuff, Ford... all tune the same way.  At least for fixed cam timing engines.  I still have yet to have Ford's virtual VE tables suitably explained to me