|Originally posted by canaman:
I wanted to swap
2.8 v6 4 spd with remanufactured 2007 3.9 v6 supercharged 6 speed with dash and ecm
complete wiring etc from a donor car to many kns on the engine so it will be a new remanufacted engine
A total gut out and set in
But wondered if a short cut would to just drop in a new 1980,s Catiliac
4.9 V8 which I heard will bolt right up to a fiero 4 SPD OR 5 SPD manual trans
ANY HELP ON THIS i AM A GREAT PUPIL AND LISTENER
1st, there isn't a such thing as a 3.9 supercharged with a 6 speed. If you are talking about the 3.9 v6 6speed combo (from a g6 gxp) it is naturally aspirated with 240hp and 240tq, no supercharger. It has been swapped into Fiero's before and turbo charged even. You will have to search the forum for more info, I only know that you will need custom wiring, computer work, exhaust, custom axles for the 6 speed?, dod delete, and more.
The 4.9 is reliable, has 200hp 275tq, and is a simpler swap (and more info available over a 3.9). From what I've read it runs out of breath at 4500 rpm, so its a good highway cruiser and stop light to stop light torque monster with low top end.
The 3.8 supercharged is the most popular and common swap and also bolts up to your transmission. It is well documented on here and you can basically buy all the swap parts from people on here. It has 240hp280tq (265hp series 3). From what I've read it sounds like crap with the oddfire 90 degree v6 setup.
I am in the middle of a 3.4 dohc swap. I felt it was a good all around package and better suites a manual trans Fiero (bolts up to the stock trans too). It gives 80 more hp than a 2.8, 7,000 rpm to work with (70mph in 2nd gear), and a very nice sound. The engine looks neat visually and it was the engine in the 89/90 Fiero prototype. The cons of this swap are no aftermarket (big problem, everything custom), more involved maintenance: 60k mile timing belt, intake removal for rear plugs (96+), has known oil leak issue from oil pump drive which requires rear head removal. Turbocharging wakes this engine up, there are a couple swaps with over 400hp.