Let the metadata decide! Search term "turbo" on this forum gets 2077 hits. Same search, "3800SC" gets 2144 hits. I am swapping a 3800SC into our 88 All-original CJB Formula. So you know my take.
To my knowledge, there are presently no forced induction kits in production for Fieros. Therefore, you're on your own.
A turbo install appears to consist of welding pipes together.
A supercharger install seems to require a fair amount of machine work to make the manifold.
Thus, I perceived the supercharger route as being out of my DIY capabilities, and I opted for turbo.
Turbos have lag, so I hope I don't find it overly apparent or bothersome, otherwise I will be fairly disappointed about having dumped 10k+ in the drain. The only turbo I've driven in my life was a turbo snowmobile, but never a turbo car.
So if you haven't driven a turbo car, and are considering going turbo, I would suggest trying one out.
It has not set me back at all, it is the culmination of a life spent struggling to restore and modify many muscle cars, most also serving daily driver duty in real time. Now I am retired, and having time to review all that work, some wasted, some not, and my conclusion is that most cars I struggled with were, from the factory too large, poorly designed, and poorly built, prone to rust, and my projects started from that hole. I prefer American cars, and my projects have always been mopars or Pontiacs. I knew I had one more build before I got out of the hobby, so I put a lot of effort into finding a vehicle worthy of my swan song, and that brought me to the Fiero. I appreciate the compact size, the very low CG, the RWD, and the familiar engine architecture. The handling is better now than in any finished project I have ever accomplished, and I have not even started any upgrades yet. I have always started my projects using a limited production version of whatever model, and this one is the lowest production version I have ever found....88 Formula in Talbot yellow with CJB T tops makes it one of 37 ever built. Why I am willing to modify such a rare beast is topic for it's own thread. The financial outlay has been substantial, but my finances are way better now than ever before, so meh. I got the car for around 4000, have spent about 500 keeping it road-ready for 2 years. I also upgraded wheels and tires for 275 total, amazing deal found on CL. I am buying all the parts for the swap at a relaxed pace, ticking them off my checklist only when found at a reasonable price. That is how I am managing the overall cost. The donor vehicle was 575 with towing (rear quarter crushed into a tree), and I used CL to sell every surplus part I stripped off it. Most of the outlay has been recovered. So, beyond that I have spent about 1500 on mounts and other swap specific bits, and about 500 on brake and suspension upgrade parts, all safely in boxes for the moment. My cradle is enroute fom Texas, and I will use that to build the drivetrain, wiring, exhaust and rear suspension as a package. The actual swap will be simplified by this approach. I am building the swap this summer, and installing it next summer. I enjoy the snarky history of Pontiac, always adding more style and power to their cars than the bean counters wanted to allow, and I believe the 88 Fiero was really the peak of that effort. I am convinced the next gen Fiero would have been optioned with a SC engine, so what I am building is the car they couldn't...for all these reasons, totally worth it.
Ahh, the age old question. Pros and cons for both. Where it comes to the stock Fiero engines, it’s really not recommended, though I have heard of the v6 getting some low boost turbos. In my opinion though, this is what it really comes down to. Turbos do have lag. It takes time for the exhaust gas to spool up the turbo. Supercharger does not. Put foot down, instant boost. However, once a turbo is on boost, it’s there. If it’s set to give you x amount of boost, it gets there and then the wastegate kicks in to keep that boost level constant. A supercharger provides linear boost. Less boost at low rpm, more boost at high rpm. This means that when you are driving around town, you’re not jumping around like a jack rabbit if you don’t want to. An improperly tuned turbo setup (or just not a very good set up at all, improper turbo for the engine) COULD lead to some craziness; such as boost kicking in and the car reacts poorly. On top of all of this, there are 3 different types of supercharger. Supers also tend to be cheaper than a turbo setup, with turbos I’ve found they need a lot more custom work to get those higher hp increases than you would with a super. Again, in my opinion, it comes down to your use. Are you auto crossing? Drag? Daily driver? A supercharger will give you more livable power. Good for all of it. Low boost for your daily drive, helping you with your power. Not bad in racing applications either. If it’s going to be a race machine though, and this is your car just for chopping madness, I’d go turbo. Also, both make great noises. Do your research.
------------------ This signature adds .5 bhp. When in doubt, gun it. 84 2m4 —in progress to— 84 2m6sc
Never had a supercharged car, but now that I have a turbo ecotec in my fiero I would not bother with a supercharger. To me the only advantage to a supercharger is the ease of installation. And since I love fabricating stuff that is not an issue for me.
Keep in mind there are two different types of supercharger: positive-displacement and centrifugal. And they behave very differently. The positive-displacement superchargers give you instant torque, but run out of steam at higher RPM, whereas the centrifugal ones don't do much at low RPM, but can make big power at high RPM.
As for turbo vs positive-displacement vs centrifugal... IMO it depends on the application.
[This message has been edited by Blacktree (edited 02-21-2018).]
Look at a dyno graph for a 2L Ecoboost. Instant throttle response and tons of torque. But power dies at about 5500RPM. Swap to a larger turbo and you have more turbo lag, in exchange for more top end power.
It really is just personal preference. There are pros and cons for different size turbos and different kinds of superchargers.
They are two different driving experiences. I enjoy driving my Series 3 L32 because the Eaton Gen 5 M90 Supercharger is balanced for my taste in terms of the instantaneous throttle response and the overall power band. But I would be lying if I said that I could pry the smile off my face every time I put my 1993 FD3S Twin Turbo RX-(H)eaven through the paces of a spirited drive. The unique sequential twin Hitatchi turbos have zero turbo lag and they provide more than enough power for my taste. A little complicated in the plumbing department...yes for sure, but I prefer it to a single turbo with lag any day.
My solution: Have one of each!
-Van
[This message has been edited by VanGTP5000 (edited 02-19-2018).]
They are two different driving experiences. I enjoy driving my Series 3 L32 because the Eaton Gen 5 M90 Supercharger is balanced for my taste in terms of the instantaneous throttle response and the overall power band. But I would be lying if I said that I could pry the smile off my face every time I put my 1993 FD3S Twin Turbo RX-(H)eaven through the paces of a spirited drive. The unique sequential twin Hitatchi turbos have zero turbo lag and they provide more than enough power for my taste. A little complicated in the plumbing department...yes for sure, but I prefer it to a single turbo with lag any day.
My solution: Have one of each!
-Van
I sort of followed your suggestion and have two supercharged vehicles and one turbo car.
Nelson
[This message has been edited by hnthomps (edited 02-20-2018).]
I forgot to mention, one reason I'm going turbo is because of the (possibly) laggy power delivery.
People often bust transmissions during the shock load of a hard upshift or launch.
Since you don't have much boost after a shift, and it doesn't build up again until AFTER the shift is complete... in theory... I'm thinking that my turbo V6 will be no more abusive to the transmission than an NA V6.
So, for me, the perceived lack of durability of the Fiero transmissions helped me to decide what kind of powerplant I wanted.
I like both. I like the simplicity of a supercharger, but I also enjoy the powers of a turbo. They both have their respective strong points. It will just come down to personal preference.
I forgot to mention, one reason I'm going turbo is because of the (possibly) laggy power delivery.
People often bust transmissions during the shock load of a hard upshift or launch.
Since you don't have much boost after a shift, and it doesn't build up again until AFTER the shift is complete... in theory... I'm thinking that my turbo V6 will be no more abusive to the transmission than an NA V6.
So, for me, the perceived lack of durability of the Fiero transmissions helped me to decide what kind of powerplant I wanted.
I'm debating whether I want to route the clutch switch wire to the ECU right now. Doing so would enable the flat-footed shift feature, but knowing me, that may spell the end of my gearbox.
Probably I won't hook it up right away, I don't think I want to break the car immediately after 1+ year of downtime for rebuilding.
Originally posted by tampalinc: Turbo sizing also makes a difference.
Yep. For example, my daily driver has a little turbo-diesel engine. But it has great low-end torque, for such a small engine. Just don't expect it to do anything useful above 3000 RPM.
My turbo ls4 has broken three input shafts. My mechanic broke the first one and since it was stock no surprise. Then a 3M input shaft and then a $1000 GM racing input shaft. I'm back to another 3M now and a light foot on the throttle. Built 4t65e tranny and the only thing that I can think of is retuning the tranny for a softer shift. So much for a turbo being easier on the tranny!
My turbo ls4 has broken three input shafts. My mechanic broke the first one and since it was stock no surprise. Then a 3M input shaft and then a $1000 GM racing input shaft. I'm back to another 3M now and a light foot on the throttle. Built 4t65e tranny and the only thing that I can think of is retuning the tranny for a softer shift. So much for a turbo being easier on the tranny!
With an autotragic you keep your foot floored the whole time, so it's not quite the same...
That said, I seem to remember that some GM cars with autos had a feature: When the transmission module was planning a shift, it sends a request to the engine computer, asking it to retard timing during the shift. It has an effect similar to slightly releasing the gas pedal during the shift. IIRC, they call it "Torque Management". Does your car use this feature?
Softening up a shift might backfire, cause that means a longer duration of slippage, right?
If it was tuned most programmer's take torque management out of the tunes. Chances are it would need to be put back, but the car will drive very different.
[This message has been edited by Spadesluck (edited 02-22-2018).]
I forgot to mention, one reason I'm going turbo is because of the (possibly) laggy power delivery.
People often bust transmissions during the shock load of a hard upshift or launch.
Since you don't have much boost after a shift, and it doesn't build up again until AFTER the shift is complete... in theory... I'm thinking that my turbo V6 will be no more abusive to the transmission than an NA V6.
So, for me, the perceived lack of durability of the Fiero transmissions helped me to decide what kind of powerplant I wanted.
Been driving a 3800SC coupled to a five speed for several years. Yes, I have played with it some. The five speed has held up with no issues.
