Matt91firebird

I purchased a 91 firebird formula 305 TBI 5 speed about a year ago. Really fell in love with the car, have already swapped out many parts trying to improve the car and bring it back to life.

The library of knowledge here on third gen has helped me more times than I can count. What I'm looking to do next with the car however is proving difficult to find the information I need. So I'm dropping my first post on third gen asking for some help. Hopefully I posted in the correct spot.

After more time researching than I'd like to admit I've decided my dream for the car is to put in an LS3 6 speed. I have read enough threads on this site to have some idea of what the steps and parts required for this swap are.

My question is this: simply purchasing a crate LS3 motor, tranny, ecm, fuel pump and most of the parts needed to complete the swap will run from about 10 to 12 grand from what I've seen. I'm considering doing this another way and if I'm nuts for even considering it I need someone to kick me in the pants now so I can move on.

I'm really trying to keep this under 10 grand when all is said and done. Going the crate route I think I'd be doing well keeping it under 15... I'm tossing around the idea of picking up a salvage title Corvette or Pontiac G8 GXP. I've never bought a salvage title car so I can't be sure on details but I'm seeing LS3 corvettes and the rare GXP going salvage anywhere from 4 to 10 grand depending.

The idea caught my attention as the right salvage title car would allow me to not only save a few grand on the motor/transmission I want but also allow me to utilize just about everything I would need for the swap right down to the fuel pump and ECM. I was hoping all I might need to buy outside of the salvage car would be a rear end that would handle the extra torque and probably better brakes/suspension to stop it but for the most part utilize everything else from the vette or GXP.

I know very little about corvette specs or what to look for with compatibility. If anyone has some advice on this or can give me a few reasons this idea is insane please let me know. My biggest concern would be incompatibility of essential parts. Drive shaft length and 6 speed linkage area being a couple of them.

My goal here is to save a few grand doing this very expensive swap. If I ran into any serious incompatibility I realize my initial 3-4 grand savings on the salvage car could quickly turn into an extra 5-7 grand buying auxiliary components plus a few more bottles of tylenol than going the crate route... Any advice is welcome. Thanks in advance for helping a nube.

Matt91firebird

I'll try and keep this brief. I posted previously in the LSX engine swap forum and have yet to receive any replies. I'm hoping someone out there has experience or considered using a salvage title LS3 corvette as a donor car for an F body firebird.

The cost of picking one up from what I've seen is less initial cost than a crate LS3/tranny and my thinking was to utilize everything else that might be compatible thereby making the swap even more cost effective. I'm just trying to cover my bases here. Will the vette drive shaft need to be cut down or will mine work, will the shift linkage be close enough to work, will the corvette ecm be compatible are just a few of my concerns.

Just a plea for advice here as I have yet to find anything online that would yield any info on what challenges I would face going this route for the swap. Or if in the long run it would be more cost effective just buying the crate LS3 kit from Hawks and spend the extra money on everything else I would need.

aliceempire

iTrader: (14)

Ls3 corvettes use a torque tube and transaxle as I recall. Making them useless to you without MAJOR modification if it's possible at all.

Matt91firebird

Thank you so much. Now I have at least something to research. Probably was a dumb idea anyway but I didn't want to discount it until I had a good reason.

Matt91firebird

You are correct. Torque tube and TransAxle. From what I read the TransAxle is way to bulky to have any chance of being modified into a 91 under body. Even if it did I'd still have to basically buy an entire rear end assembly to accommodate the transaxle so either way that about makes my decision easy. Thank you for chiming in.

88TPI406GTA

The LS3 also is in the 2010-2015 CamaroSS (manual) and the 2009 G8 GXP....these use standard transmission options (not torque tube). If I were to look at this swap (which I have), I would strongly consider the GM crate engine route, and add the GM electronics package to control it....especially the 525HP version. Cost isn't cheap, but its a brand new engine.

five7kid

iTrader: (14)

Weekends are my "busy time" from late-April to mid-October. And yesterday was slammed. Sorry I couldn't get to your question immediately.

But this still belongs in the LTX and LSX sub-forum.

jmd

iTrader: (4)

A torque tube T56 or TR6060 is a fair amount of work to convert to engine-mounted. I would attack that project but many won't. You won't be using that driveshaft for a solid axle car. I think whole cars make great donors but you run the risk of condition of the engine, and trans., and mileage vs. new. Far less risk going new.

Matt91firebird

Thanks everyone. I'll drop something here when I scrape together a few more pennies to go the new crate engine route.

88TPI406GTA

For what's it worth, I keep thinking of dropping in an LS3 into my Camaro or Firebird, because I love that engine in my G8...I keep thinking how much fun it would be in a lighter car.

Then, what gives me pause, besides the money, is finding the right EFI controller. I really don't want to become an engine tuning genius and would prefer plug and play...seems like GM solution would be best/easiest here. Also, then there is paperwork/documentation on the swap that would be easy to provide if you ever wanted to sell it....versus taking a JY 6.0 and building it up at Joe Bob's speed shop.

five7kid

iTrader: (14)

The GM controller will certainly get you around the tuning issues.

If you have to comply with emissions inspection/test, you can go with the E-Rod engine kit.

Jaysz28

iTrader: (30)

Where are you at in Fl?

88TPI406GTA

For the file:

This is what I was referring to: http://paceperformance.com/i-7788424...s-sensors.html

For $1,250....It contains ECU, wiring harness, sensors, etc. for the LS3 525HP motor...just plug and play, no tuning required. They have these for LS3 at 430HP, 480HP and 525HP levels.

The LS3 525HP engine with this controller package is about $8,700. While it initially gave me some sticker shock...I realized that this is a pretty good deal for 525HP engine/controller, from GM no less.

scooter

iTrader: (11)

The problem I have with the other LS3 engines with over 430hp is that they are all exactly the same except the cam, literally. So why is the 525 like $1,700 more? The ECM package is the same price as the other controllers. I think I'd rather buy the base, use it for 3 years and then swap the cam later, it will still be a LOT cheaper

88TPI406GTA

The price of the base LS3 has come down...and the 480HP version is now about $400 more...probably the better deal then.

Why the price difference? Warranty...GM is probably hedging that the higher HP motors will have more warranty issues, and they are passing the cost on. Either way, still a good deal for a complete package...with a known quantity.