Hello, I'm gonna try and write down my build plan for this so it may be a lil long sorry.
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Right now my idea/goal is to be putting a L21 gen vi 454 Big block into my 86 z28.

However, I am having quite a hard time locating this specific block, as it would have only came in 1998-01 gmt530's the commercial medium duty trucks.

Not sure if any members could point me towards a pre-owned engine site that doesn't suck at marking their inventory properly...

Regardless, They allegedly had mechanical fuel pump bosses and forged internals. (I wouldnt mind getting confirmation on if every L21 was mechanical fuel pump capable.) Worst case scenario I think I can cam swap and drill a hole in the block....



My car is already setup with the following,
fitech go street efi 400(won't be used), the force fuel mini tank fed by a mech. fuel pump, a lt1 t56, 4th Gen rear end 3.73 posi, a cammed 305 sbc with long tube headers, and true duals the whole way back too. Also on drop springs, caster camber plates, panhard lowering bar, new poly everywhere. 245/45/17's all 4 corners iirc. Anyways it needs a big block now

I think I have pretty much everything else figured out, I know I may need to swap the pump in the mini fuel tank tho, it's only a 340lph and 58psi, so a little light for a big block. Will prolly be good enough for starting and light pulls so I'll just worry bout it later.

As far as ignition i believe I can use an LS standalone for the Coil near plugs, throttle, sensors, and whatnot. I was planning on haltech stuff cuz it's badass but I also don't think I really need that much of a race system for my ******* sled with no traction control and a big block up front. And I could save that money for headers or something else. I've seen people run these engines on 80 dollar harnesses and a truck PCM they unlocked.

As for the flywheel it will be whatever centerforce says I need, I believe it's the same as the 502 flywheel, could be wrong tho. Not sure if I'll need to change clutch or anything. I'm currently pull style clutch on a 1pc rms.

As far as exhaust goes I would prefer long tube headers for the sound, I don't know of any cheaper ones that easily fit a 3rd gen tho. So most likely ill use the cheap shorty set that's pinned in the big block swap page. I also have the hooker Blackheart t56 x member which helped me get my x pipe nice and tight to the floor.

Gonna get a eBay radiator most likely. I currently have 4th gen dual electric fans hooked up. So I'll just reuse em on the new rad.

I'm not sure what to do with the belt drive of a BBC in a 3rd gen tho. I'm assuming I can plumb power steering lines and water lines to the stock bbc components similarly to a SBC. I bought the hydraulic ac line tool finally so maybe I'll try to do ac too.

I'm trying to keep this build kinda low-buck, but will buy the nice **** when I need to (ie custom flywheels and cross members) but will probably fab my own parts 95% of the rest of the project.

Oh and I guess I'll answer the why not ls and why not 383 sbc questions. You are correct. I probably would prefer a 6.2 built right, it will probably be a better, longer running motor, better driving car, less hassle. however, I have an lt1 t56 cuz like a dumbass I gutted a 95 firebird 6 speed instead of a 98-02 donor. And on top of that my fuel system is really only setup to function if the block has a mechanical pump, so basically limits me to sbc right off the bat. And like now the question of cheap BBC swap or expensive 383 build kinda seems like cheap BBC wouldn't be so bad.

What is intrigueing to me about the L21 build instead of the other more mainstream approaches is mainly, the chance of mechanical fuel pump for better streetability. The coil near plug design which really simplifies the engine bay imho. And the fact that it's a 454 and not many people have big block 3rd gens.

So really my biggest needs are met by the L21, which is a robust ignition system, with provision for mechanical fuel pump, and a lot of torque. Now I just need to find one.
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it's not hard to install a BBC in the 3rd gen Camaro. cast iron blocks & heads remember to install front end springs to hold the lbs. added
there is room for most everything. stock power steering even AC but its tight.
exhaust headers are all over the place. that's what stops most of guys from doing it. ya can use stock cast Iron manifolds, if ya want to.
but in the end why..
most go big block for the power.

 

I am currently putting together a 97 gen 6 454 i found on marketplace that was running in a vehicle. They are way more available than the specific version you are looking for and for a good price that might free up some cash to buy new parts. I replaced the factory FI intake with a 502 ramjet intake that i purchased, for headers i went with the patriot 1 7/8 recommended and a summit oil pan although i didn't like there gasket fitment. Be careful about timing chain as the gen 6 is a different size gear thickness to allow for the crank signal and the summit replacement is wrong despite it saying it fits. I had to get a melling replacement for the correct thickness> i do not see many of the kodiac that are big block near me, mostly diesels