LS Swap into 73 Firebird
#1
LS Swap into 73 Firebird
To start things off I'd like to say that I am new to the site and
forums in general, so I apologize in advance. Back story is that I have
dreamed about doing a resto mod for years and finally got out of
college and bought a 1973 Firebird. The guy told me the car was from
San Antonio but doing some research I later found out that it spent
most of its life in New Jersey... So there is considerable rust in the
floor pans and a little on the frame. I didn't mind since I am so new
to the hobby I just wanted a to start learning and getting my hands
dirty.
My plan is to do a LS1 (or LS2 if I can find it for the right price)
with a T-56. Attempting to plan it out, I hear good things about the
BRP Trans cross member and motor mounts. My question is: with my holes
cut for patch floor pans (seen in the picture) the Trans cross member
is very accessible. Should I remove the current engine and install the
BRP cross member since it will be much easier to drill the holes for
installation. In that case, would I have to purchase my engine and
transmission in order to get the fit right? With the floor pans
installed, I don't see how it is possible to install the cross member
without taking the body off the frame.
I am open to all advise, being new to LS swaps and resto mods. Thanks
forums in general, so I apologize in advance. Back story is that I have
dreamed about doing a resto mod for years and finally got out of
college and bought a 1973 Firebird. The guy told me the car was from
San Antonio but doing some research I later found out that it spent
most of its life in New Jersey... So there is considerable rust in the
floor pans and a little on the frame. I didn't mind since I am so new
to the hobby I just wanted a to start learning and getting my hands
dirty.
My plan is to do a LS1 (or LS2 if I can find it for the right price)
with a T-56. Attempting to plan it out, I hear good things about the
BRP Trans cross member and motor mounts. My question is: with my holes
cut for patch floor pans (seen in the picture) the Trans cross member
is very accessible. Should I remove the current engine and install the
BRP cross member since it will be much easier to drill the holes for
installation. In that case, would I have to purchase my engine and
transmission in order to get the fit right? With the floor pans
installed, I don't see how it is possible to install the cross member
without taking the body off the frame.
I am open to all advise, being new to LS swaps and resto mods. Thanks
#3
Welcome to the board! Trans Am Country and Nasty Z28 are other good 2nd gen boards that have helpful members.
It really depends on how far you're going with this restoration. It looks like ambition isn't an issue, so if you have the tools and space I'd recommend dropping the entire subframe from the body. That will give you worlds of access to everything you need, allow you to route your wiring harness on the engine out of the car (trust me, you don't want to do the harness layout with the engine between the fenders), you can easily refinish the entire front suspension/steering, and replace the body bushings. Obviously its up to you, but that's the direction I'll be going when I swap my '79 T/A.
And as for the LS2 vs LS1, I wouldn't waste your money paying the premium for the extra .3 L... spend that money saved on worked heads for the LS1 and you'll make more power in the end. Try finding a 1999-2002 f-body take-out with all accessories, harness, and PCM if you can, and pay a little extra if you need to. That setup is almost taylor made (oil pan, accessories, harness is easy to mod, etc) to drop into a 2nd gen with the 1" setback plates.
Oh, and since you're new to the board I'll give you a heads up: post plenty of pics! Haha
Good luck.
It really depends on how far you're going with this restoration. It looks like ambition isn't an issue, so if you have the tools and space I'd recommend dropping the entire subframe from the body. That will give you worlds of access to everything you need, allow you to route your wiring harness on the engine out of the car (trust me, you don't want to do the harness layout with the engine between the fenders), you can easily refinish the entire front suspension/steering, and replace the body bushings. Obviously its up to you, but that's the direction I'll be going when I swap my '79 T/A.
And as for the LS2 vs LS1, I wouldn't waste your money paying the premium for the extra .3 L... spend that money saved on worked heads for the LS1 and you'll make more power in the end. Try finding a 1999-2002 f-body take-out with all accessories, harness, and PCM if you can, and pay a little extra if you need to. That setup is almost taylor made (oil pan, accessories, harness is easy to mod, etc) to drop into a 2nd gen with the 1" setback plates.
Oh, and since you're new to the board I'll give you a heads up: post plenty of pics! Haha
Good luck.
#4
As for advice, the best advice you can get for the most friendly swap in my opinion would be to find a wrecked 99-02 LS1 fbody car. Swap the engine/trans/ecu/wiring and sell the rest. I bought a complete car, took everything I needed, and the swap to date hasn't cost me anything out of pocket since I sold off enough parts to cover the cost of buying the car. I still need to buy a few things, but overall almost no out of pocket money. FWIW, not for everyone but can save big $$.
Ryan
#5
Agreed that TAC and Nastyz are both helpful site. I would also like to mention that depending on the future mods, it may be worth while for the OP to get the LS2 as it can open the door to future mods that aren't possible with the LS1. For example if you wanted to run the L92 heads and LS3 intake, you can do that with the LS2, but not with the LS1 since the bore is too small.
#6
It really depends on how far you're going with this restoration. It looks like ambition isn't an issue, so if you have the tools and space I'd recommend dropping the entire subframe from the body. That will give you worlds of access to everything you need, allow you to route your wiring harness on the engine out of the car (trust me, you don't want to do the harness layout with the engine between the fenders), you can easily refinish the entire front suspension/steering, and replace the body bushings. Obviously its up to you, but that's the direction I'll be going when I swap my '79 T/A.
I am ambitions but since this is my first time to do everything and i have no guidance but these forums and youtube, I am slow. I have the tools (or at least acquiring as a go), the space is what i am lacking. I am doing it out of my parents garage and the space is limited. Otherwise I would love to do a frame off restoration. I hear that can add on a couple thousands to the final price though. I also wanted to media blast the whole thing but without access to a trailer, attempting to keep a small budget, and getting really antsy to start my first project i kinda just jumped in.
So assuming I dont do a frame should i just continue with the floor pan installation and tackle the trans cross member issues when it comes? The idea was for me to do one step at a time, install the floor pans, so I dont get overwhelmed and give up (because of course all my friends and family think I'm absolutely crazy for taking this on at 23 with no experience).
Also how do you install the BRP trans cross member. On their website the instruction says just slide the transmission crossmember into the chassis and bolt the mount loosely... mark the crossmember mounting holes on the frame and drill them out. With the floor pans in how does one drill on the top of the frame??
#7
Welcome aboard, always good to see another Pontiac. Don't worry about your age, all of us started somewhere, and most started with a car not nearly as good as yours. Ask questions and read the stickies. Like the old proverb, measure twice and cut once, plan and investigate before you charge ahead. Another proverb I use is , there is job I cannot accomplished with brute force and ignorance. This how we all learn, some mistakes are just more expensive.
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#8
#9
BRP swap kit on a 5.3 or L92?
Has anyone used the BRP ls swap motor mounts on a a 5.3 L or L92 with a T56 in a 1970-81 F body? I'd be interested if it was pretty much bolt on or any lessons learned during install. The price is so much lower for those engines compared to a ls1. I figure with some mods you can get similar power.
#11
Hey, man.
I figured I would chime in since nobody else has. You're gonna need to pull the subframe.
Don't be scared, it's not that bad. Youtube it, or just look around for everything that needs to be disconnected, brace the shell on jackstands and 2x4s and get to wrenching.
I'm picking up a 71 bird this weekend. I'll be dropping in a LQ4 and T56 eventually. Keep us updated on your project!