'94 Firebird formula

Food for thought, a 5.3 iron block engine weighs more than an LT1 with aluminum heads. About 35# heavier, maybe more. You are trading a SBC block for a deep skirt, taller deck block. Without camming the 5.3, your putting a 285HP motor in replacement for a 275HP LT1, both are roughly the same but the 5.3 peak torque rpm is higher.

I know you are putting a mod list together for the swap, but if you are doing a iron LS motor, hold out for 6.0 with flat top pistons and some 243 or 799 heads. A mild cam will put you over 425 and the 35# will be more than worth it.

I just see you taking weight out of the car, doing the 5.3 doesn't make sense.

I'm not knocking an LS motor, but the #'s don't make sense.

Just my $0.02, constructive input.


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I see what your saying, I wanted to go with a 6.0 but the cost difference is just too much for me. I picked up my 5.3 with a harness and PCM for $350 and at the time couldn't find any 6.0s for less than $1200. My lt1 craps out any time it rains so I really have no interest in messing with it at all. It seems to me like a waste of $ to buy parts for a lt when I can get a full 5.3 for less than any ignition solution. People keep saying I'm dumb for not just keeping the LT when my goals are so mild but what fun is a car that doesn't start up 50% of the time??? Evert time I drive it I spend the whole time wondering it it'll need to be towed home.


I had planned to pull it and swap in a carbed 355 a friend had but then I found the 5.3 for $150 less than the 355 so Went that route. This is a budget build so I'm trying to keep costs down, I like that with a 5.3 setup, if the motor gets messed up I can source a cheap replacement easily. I've thought about nixing the H/C/I idea with the 5.3 and just doing a turbo w/ stock long block instead because these seem to love boost.

Would the smaller displacement 5.3 be more reliable with boost rather than trying to keep it NA and still make he same 450-500whp? I know I would not want a mild cam either way, if I'm going to put one in id want it to be more towards the aggressive side. I don't care much about losing drivability or not keeping it quiet with a big one, I'd rather it sound good and make better power.
 
Talk to Brian Tooley before ordering a cam. He can set you up with everything you need to reach your goals. Very respectable guy in the LS world and wont steer you wrong. pm me if you want his number and Ill get it to ya.
 
I'm not going to say you can't get to 50 who with an NA 5.3 with stock heads...... but I don't have a cost effective combo to get you there either.

How about slap the 5.3 in and run it. Work out all the swap bugs and wiring etc and build a 6.0L later.

Boost is an option but you'll have $1k into the turbo setup even with a JY build.

You can tell be to buzz off anytime, but I'd hate to see you put a bunch of time and effort into something that's not going to meet even your mildest goals.

Oh, and a reman opti is still a cheaper option than the LS swap.

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I see what your saying, I wanted to go with a 6.0 but the cost difference is just too much for me. I picked up my 5.3 with a harness and PCM for $350 and at the time couldn't find any 6.0s for less than $1200. My lt1 craps out any time it rains so I really have no interest in messing with it at all. It seems to me like a waste of $ to buy parts for a lt when I can get a full 5.3 for less than any ignition solution. People keep saying I'm dumb for not just keeping the LT when my goals are so mild but what fun is a car that doesn't start up 50% of the time??? Evert time I drive it I spend the whole time wondering it it'll need to be towed home.


I had planned to pull it and swap in a carbed 355 a friend had but then I found the 5.3 for $150 less than the 355 so Went that route. This is a budget build so I'm trying to keep costs down, I like that with a 5.3 setup, if the motor gets messed up I can source a cheap replacement easily. I've thought about nixing the H/C/I idea with the 5.3 and just doing a turbo w/ stock long block instead because these seem to love boost.

Would the smaller displacement 5.3 be more reliable with boost rather than trying to keep it NA and still make he same 450-500whp? I know I would not want a mild cam either way, if I'm going to put one in id want it to be more towards the aggressive side. I don't care much about losing drivability or not keeping it quiet with a big one, I'd rather it sound good and make better power.

I'm not going to say you can't get to 500 rwhp with an NA 5.3 with stock heads...... but I don't know of a cost effective combo to get you there either.

How about slap the 5.3 in and run it. Work out all the swap bugs and wiring etc and build a 6.0L later.

Boost is an option but you'll have $1k into the turbo setup even with a JY build.

You can tell be to buzz off anytime, but I'd hate to see you put a bunch of time and effort into something that's not going to meet even your mildest goals.

Oh, and a reman opti is still a cheaper option than the LS swap.

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I'm not going to say you can't get to 50 who with an NA 5.3 with stock heads...... but I don't have a cost effective combo to get you there either.

How about slap the 5.3 in and run it. Work out all the swap bugs and wiring etc and build a 6.0L later.

Boost is an option but you'll have $1k into the turbo setup even with a JY build.

You can tell be to buzz off anytime, but I'd hate to see you put a bunch of time and effort into something that's not going to meet even your mildest goals.

Oh, and a reman opti is still a cheaper option than the LS swap.

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i see what your saying. i like the idea of throwing the 5.3 in but leaving it stock and saving for a 6.0.

i like the idea of a turbo because it's an easy formula, and easily upgradable later. the reason i wanted to stay NA was to keep things simple. fitting a turbo and piping in a car that wasn't supposed to be is a PITA. chasing fluid leaks from all the extra lines etc. with NA there 's nothing extra to shove in there, not much extra heat to worry about. and with my lower power levels boost isn't the obvious choose. but like i said i like the idea of throwing the 5.3 in and just spraying it while i work out issues and getting together a 6.0 with goodies on the side to swap over when it lets go. i also will eventually need to upgrade the transmission and rear so it'll all be a slow process.

i don't mind at all, i'm open to input from anyone. this is my first time doing anything v8/ls/f-body so i'm a newb, i need all the input i can get lol

a reman opti is cheaper, but not having to deal with a opti ever again, being able to have friends tune it for me, being able to drive in rain if i need to, among other things make the LS based motors seem like a better choice IMO
 
Talk to Brian Tooley before ordering a cam. He can set you up with everything you need to reach your goals. Very respectable guy in the LS world and wont steer you wrong. pm me if you want his number and Ill get it to ya.

will do for sure, i'm by no means set on that cam and am open to input.
 
Opti ' s live in rain. I have the bcar timing cover if you want to swap over to a vented opti. But you can vent the vintage you have. I have had close to 10 lt1 cars and only did one opti in all that time. I should still be able to tune an lt1, I have an AKM cable and obd-1 tunercat setup.

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it's already got a vented MSD cap, but i don't think the opti itself is vented, or something weird like that. how much is a LT1 with 99k worth if i sold the whole drop out? has pacesetter headers too. i'll either sell it or keep spraying more. i want to spray a bigger shot but didn't want to deal with mail order tunes and people talk about bricking the PCMs.

i dont know how people drive in the rain, something must be wrong with mine, or the cowl hood pulls water up or something. i got stuck in it coming home one day, got it towed home and let it sit till morning in the garage and it fired up.
 
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94 FCars did not have vented optis. 94 b and d cars did. If your car has a vented cap on a non vented base, it may be a leaky mofo. I'm not sure that combo will seal at all. That could be your issue there. A vented opti with good hoses going to the induction will work just fine. I never ran an MSD cap, just Delco units.

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very well could be. i know the cap is vented, because i had to hook the vacuum harness to it, but i could only find one port for the life of me. is the second port on the opti itself?

this stuff is so confusing and a PITA, exactly why i want to swap to the ls and just be normal and not have to worry about the start aligning in order to get spark lol .
 
I like the LS stuff better myself. The opti has both vents on the same side, one above the other. Drivers side. Hook one side to the air duct before the throttle body, the other on one of the small hose fittings on the left side of the intake. I might have a core unit laying around still, I'll take a pic.


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Fricking unreal...
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The wife loves lugging boxes in the house all day from the delivery guys lol
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Thanks Superman09 for the care package!
 
Thanks! I'll be having more fun once it's all on the car lol

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Thanks Darko for the FAST rails.


Ohh yeah it's getting plastidipped too.
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Had to get 18" wheels to run the brembos, I ground down one to fit a 17 and it was pretty sketchy looking. Soooo I traded my ZR1s that I loved for some C6 DD 18s. They need wider tires but it'll do. They were chrome, and that wasn't happening, so plastidip happened. Black with a layer of glossafier.
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Also tried plastidipping my mirrors red, not a bad match! They need some glossafier, but will be anthracite when the car gets sprayed so they're fine matte.
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Cool man. I like the chrome but I know that is not the "in" look. Just curious, what is the reason for the V6 style tail lights?
 
I like the chrome better. The black wheel look is overplayed now IMO. Start tossing them parts on the car, it sucks when you have a giant pile you feel like you will never get done :lol:
 
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