1985 Fiero Gt engine Swap Question

  • Thread starter Thread starter ZaxelColdstar
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ZaxelColdstar

Hey guys, I'm brand new to the forums, but I got a probably over asked question.

About a month ago I got a 1985 fiero gt, with the 2.8L, and it runs great, no problems except the cursed dancing oil pressure needle (which I'm going to get a new OPSU to fix) but, aside from that I want to do an engine swap, in the future, for it. My dream is an LS2 (good luck huh?) but right now I was looking more at a 3800 Supercharged L67. I'm pretty sure I can find a wrecked Impala SS somewhere in Houston for that one, but here are my concerns.

1. How much would the L67 cost? Plus would the 5 speed trans. from an 80's Isuzu (the 5 speed manual) work with it?
2. How would I go about installing it? I do most of my own car work, and how difficult is it to install? Would it fit right in, just needing new mounts or would I need to do some body work?
3. Is there some site somewhere that has some guide to this?
4. Cost yet again, I'm a college student so I need to know how much I gotta save up.

I would rather prefer the Supercharged L67 because I can run under a 12 second quarter mile, and coupled with a good 5-6 speed tranny, I'll be happy enough.
 
1. Cost depends on the engine. Some folks have found engines for as low as $300 and some as high as $1500. It all depends on the mileage, condition, and the region you live in. You need to use the Fiero transaxle. It will bolt up to the engine. The preferred transaxle is the 1986 thru 1988 Getrag 5-spd. However if you want you can also use a 2006 G6 F40 transaxle. This is a 6-spd manual trans. The Isuzu transaxle will not last long under the power of a stock 3800SC especially if you plan on running it down the drag strip.

2. If you do a google search there are a few sites documenting this swap. For specific questions and parts required (wire harness, mounts, manual flywheel, etc.) you can contact West Coast Fiero ( www.westcoastfiero.com ) or Sinister Performance ( www.gmtuners.com ) The swap is mostly just mounting and wiring. The only "body work" is you need to put a notch in the decklid support for clearence where the alternator and blower pulley sits.

3. see links posted in # 2

4. Cost is hard to say. Some have swapped in a 3800SC for around $1500 and some have spent over $8000. It all depends on cost of the engines and if you buy some parts or make them yourself. (like the mounts and harness.)

If you think just dropping in a stock 3800SC with a manual trans will get you under 12 seconds, You will be in for a surprise. The 3800SC in stock form is 240-280 hp and most Fiero's with a stock swap run in the low/mid 13's. You are going to need around high 300hp range to get under 12 seconds. While the 3800SC is a great platform to start with and the mods are easy to find ( Pulley's, cams, inter-coolers, etc. ) Getting to the high 300 or low 400hp range will take using the proper mods and doing the proper tuning (dyno-time) which isn't a hard goal, but this will now add to the cost of the swap. Also if you are going to modify the engine for more power you might want to consider one in very good condition and low mileage which also increases the cost. Your best bet is to save up about $2500 and then swap in a good condition/low mileage engine. Then drive it around a while and then you can research which mods you want and their cost.
 
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Listen to Oreif kid, he's pretty accurate with this stuff. However if your looking for cost efficient power, just do the 3400 swap. It takes the same bolt ons from your 2.8L it'll get you that extra touch of power. It does not require any extras like ECM or Harness. It doesn't require any notching. You'll actually aquire better fuel economy. And, most importantly, unlike the 3800sc swap, your car will be a complete sleeper. You pop the hood and almost no one will know that it's not the stock engine. And, for a little bit more you can throw on a couple of mods that'll get you into the 230hp-240hp range.

Just something for you to ponder.

Oh and one last thing, no customizing motor mounts.
 
Thanks for the help guys, I've been asking around everywhere for some help on doing this to my Fiero and so far yall have been the most helpful.
 
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