It sounds like a sit-down with your uncle’s friend would get you a lot more info. And find speed shops in your area, drop by and start talking to folks.
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I don’t really care about the flagging thing and I would love to sit down with my uncle’s friend except right now he literally only has time to eat, sleep, and work since his shop is his but he doesn’t work there he is just the owner of the shop and has employees that he hires to do the actual shop work he just knows how to use a dyno because he used it before he was able to hire people to do the work for him since he inherited the shop from his dad and actually only likes doing car stuff in his free time.
That’s where you’re setting yourself up for a fall. Trial and error modding is fine when you’re trying to get a 98hp Honda CRX up to 130.
Trial and error shooting for 600+ horsepower (or more like 1000+ if you’re really going with 17lbs) is just going to blow stuff up and cost you a lot of money.
There are guys who do this for a living, who are very good at it, but when they start reaching for 4-digit horsepower readings, things go wrong.
You’re talking about Veyron territory at the numbers you’re aiming at, and just look into how hard Bugatti had to work to build the engine for that thing. And in amongst the excellent points @Mustangman made, he talked about cooling. The Veyron has 10 radiators. If you don’t get the cooling right the first time, no trial and error, you’re gonna destroy that engine and have to start all over.
You really, really, need to lower your expectations for your first build. Get your hands on some cheap 80’s econobox and modify it for decent, but not excessive, power/handling gains. That’ll get your toe in the water and give you an idea of what you need to do for your Roadrunner project. And even then you’re gonna be in over your head.
I’ve been modifying cars since the late 90’s and I wouldn’t even consider attempting this even if someone else were bankrolling the entire thing. I’d screw it up. You’re much better off taking the Roadrunner to a good speed shop and telling them “Here’s $80,000. Make car go fast now.” And then when they inevitably run over budget you have $20,000 left to make up for it. 
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What engine is in the Roadrunner now? Make some mild modifications it and improve the suspension. Maybe put a different exhaust in it. After you modify it and drive it for a while, sell it, take what you learned, and buy something else for a more ambitious build. Or keep the car your grandfather gave you after a mild modification and move to a second staggering on it.
If you’re putting a new drive train in something, consider a junk yard car. All you really need is a body and frame. You will replace Avery thing else anyway. No need to possibly butcher a perfectly good car a relative gave you.
I’ve modded many things over the years and I’m intrigued by what you are trying to do BUT, I’m afraid I can be of no help on this one as your wants are kind of out there a ways. Seventeen pounds of boost on a high compression engine is asking for the Mother of All Explosions. The engine sans turbocharger requires 110 octane race gas without factoring in the boosted aspect at all. I wish you the best, BUT…
it’s sacrilege to put a Chevy motor in a Mopar product! Boooooo… from a Mopar lover and ex-Roadrunner/Superbee owner. (Calm down, just tweaking you a bit.)
I feel the same way about Dominator on Street Outlaws after finding out his big tire Dart has a Chevy motor in it. Booooooo…
it’s sacrilege to put a Chevy motor in a Mopar product! Boooooo… from a Mopar lover.
Agree 100% from another Mopar lover.
But you guys are cool with putting a Fiat motor in one, right?
Sorry, couldn’t resist.
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Boooooooo to you too…low blow. 
I kind of feel the same way when I see all of those 32 through 34 Ford Roadsters going through the auctions and almost all of them have Chevy engines in them. I hate that.
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Instead of Chevy crate engine that would essentially have to be rebuilt to turbo standards, why not drop in ready-to-run Mopar Hellcrate engine? Only about $19k from Mopar, maybe a tiny bit less from other speed retailers. It may not be quite 1000hp, but it’s a proven combo that’ll probably be much more driveable and reliable.
I agree with the Hellcat engine suggestion. There’s a company in TX that can boost the Hellcat up to 1500 HP for something like 10-12 grand. As mentioned, you then run into the next weakest links in the chain; transmission, driveshaft, rear axle, and tires.
At least with that setup you are in for 30 grand and still have 70 to invest in the weak links. An added bonus is that blowing up is far less likely and God would not smite you down for going with a Chevy motor… 
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@dweed384
Some of the replies you’ve received so far may sound harsh, but there are few places where you’re going to get direct honest help from contributors with serious years of experience and skill.
Most of those replying to you had a passion and interest in their youth to tinker, modify, and make a car run faster. I know I did. And many of us have lived through the limitations described. While I never reached the point of blowing up a drivetrain, I know (and saw) many who did.
I am puzzled about one thing. It appears you have $100,000 to spend on these mods. But when Beancounter suggested college, you dismissed it due to the expense.
If you have a passion for this, please don’t discount educating yourself in it. You’ll love the material and will learn a lot. When you get out, not only will you be employable in a field you love, but you’ll have the free time and income to do your mod project. And, from an engineering perspective, you’ll be able to understand and explain why all the concerns expressed to you in this thread are true.
I stress pursuing an automotive education because that’s what I did years ago, and I’m so glad I did.
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The equipment, tools and shop space rental for a year would likely eat up half the budget. Then the training in welding and fabrication would take a year or so and cost over $10,000 I would guess. If you’re going to dream, dream big I’ve heard. There are hundreds of rusted out dreams pulled out of garages and sold for scrap iron every year. In my little hick town there have been at least 6 Cobra kit cars and the donor car for parts sold for pennies on the the dollar cost. But people throw $hundreds of thousands away at casinos and all they learn is the house always wins and you really might get through and have just what you want. Good luck.
Take baby steps.
Walk before you run.
Turn away from instant gratification.
If you try to start at the top there’s only one way to go from there.
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First off I know this is just advice I’m not taking it personally. Second of all, I like doing car modding and stuff as a hobby that’s why I was a bit on the edge about going to a whole extra college for something I’m only going to be doing as a hobby. Third, I looked at the Hellcat motor and I feel that it would actually be better. The reason I say that because of all the reasoning is given on the thread about it and B it has higher horsepower starting off and for not much more than the chevy engine that I was going to put in my roadrunner. Fourth I never said my grandpa fixed it up with good parts he just got parts out of a junkyard to make it to the point where it is driveable enough for me to drive it home. Another thing is I wouldn’t have to rent a shop since my uncle’s friend doesn’t care if I use his shop. Finally, the whole $100,000 thing is over time, I’m not going to be able to just all the sudden drop $100,000 into a car since right now I can barely live in an apartment that I’m splitting with my friend that I’m going to be doing this with. This whole challenge thing is at least still like 6 years down the road before we even start it and it is probably going to be like a 3-8 year project. Also, the only reason I wanted to put a chevy motor in it is because I’m a Chevy guy that likes the look of the 1973 Plymouth roadrunner. Also one thing I just realized, I pretty sure that the hellcat engine might get better mileage than the Chevy Big Block I chose. But one thing I’m hearing from these Mopar guys is that I should put a mix of Chevy and Fiat parts into my car. I may be going with the hellcat engine but I’m still going to put my NGK sparkplug in since I am considering adding a turbo to add just a little bit more power since I’m pretty much saying screw it to the 1250 hp idea for my car and I’m just going to aim for an 1100 hp engine and since this hellcat engine has better. There is one non-modding thing that I am curious about though and that is why everyone hates Mopar? I personally have nothing against Mopar. The only car brand that I’m against is Ford. Also is the shop that @ok4450 was talking about Baily’s Hyperformance Factory or serious hp. Just so you know I am updating this as I go like I’m doing multiple posts but I’m not since when I try posting it is saying wait 2 hours. Right now I’m questioning if I even want to go 1100 hp since I mean I used the calculator that is supposed to help you know the stats of the turbo you need to get your engine to the desired horsepower rating and it was saying that I would need even more PSI boost than the first time and I’m just like that calculator must be shit since I only want like a 300-390 hp boost. Is it even possible to run a car that is supercharged and turbocharged? If so then what would I have to change to make it possible?
There are compound supercharger/turbocharger systems, but why add the unnecessary complexity?
The Hellcat is supercharged and intercooled. Stock boost is at 11psi. While it’s rated for 707hp, some claim the actual output is over 800. The PCM that is supplied with it is supposedly unlocked and can be further tuned.
If you want more hp, consider the Mopar Hellephant crate engine, with 1000hp out of the box. It’s considerably more expensive though, at $30k, plus a couple of other recommended kits for installation.
Now you crossed the line with somebody just trying to help…
You don’t seem to be getting the replies you want here and can’t grasp the concept that this is a Forum and as long as the posts meet the site rules we can post almost anything we want.
You are reaching way beyond your ability and knowledge plus it seems that you really can’t afford to do this project. You might be better served to find a more receptive forum.
Doesn’t seem like it since in my opinion it was blatantly obvious that I wanted to do the work myself and he just says to go to a website and buy a more powerful engine instead of actually doing the work for more horsepower. I do admit that I was harsh and I am sorry about that @Bugmenot I’m just trying to get some help and this is the only website that either lets me post or has people that respond and I’m just getting irritated because I’m just trying to plan a fun modding project and it just seems like you guys are calling me an idiot for overcomplicating things with this project planning and I’m just trying to plan a project and get a little help not be lectured for what I’m doing wrong.
Everyone here is just trying to help and I do not see Bugmenot’s comment as rude or harmful in any way. It was a helpful suggestion; nothing more.
You are asking for something kind of out of the norm so to speak and most of us who have modded things have never really reached as high as you want to go. I cannot answer your question about running a super and a turbo together as it is something I have never attempted.
However, I will say that even in lesser projects I’ve gotten involved with they ALWAYS end up requiring more money, time, and frustration, and profanity than what was planned. That’s a given.
One other reason for the Hellcat (or even better the Hellephant) is that it will keep Mopar with Mopar and that in turn will lead to a much better resale value if you decide to sell the car in the future. A year or so ago a late 60s Charger Resto-Mod with a Hellcat engine sold for 200 grand. I have no idea of the total investment in the car but for a non-original car that’s a pretty healthy return.
I support you in whatever you decide to do but as a die-hard Mopar guy it’s got to be a Hemi IMO: either store bought or built from the ground up. I still bleed B-5 Blue and Spring Green…
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Hi @dweed384 as @ok4450 and @texases have said, @Bugmenot was just trying to help. We don’t usually get a lot of modding discussions here, but people are actually giving you constructive feedback. I get that you’re frustrated, but one sure way to get no one to respond to you is to be harsh as you say. It’s ok to be frustrated, but please don’t take it out on the users. It’s a good discussion and I wish you luck, whichever route you choose to go. Please don’t curse, tho. Thanks.