Need Advice (validation) On Upcoming Project.


Dec 20, 2017
Greetings from Utah.

I've been researching and planning a project car for the past few months, and for many reasons, I think I've decided on building a supercharged 99-04 Mustang GT M/T. I'm trying to keep the build under $10k. I know it's tight, but I'm patient and willing to get creative. My goal is a ~400whp street car that will maybe see an occasional day at the track. If I can build something that puts down more power than a brand new mustang GT, I'll feel accomplished.

Up until yesterday, I was planning on building a forged shortblock, but my reasoning was sort of a slippery slope
1. If i'm going to boost, I should start with a fresh engine.
2. If i'm going to start with a fresh engine, I should used forged internals.
3. If I'm going to use forged internals, I might as well add more boost.
4. If I'm going to add more boost, I might as well build a stronger engine.
5. Now I need to upgrade the rest of my powertrain to handle the power.​
And thus the process repeated itself until I was looking at a $25k track-only car that was a far cry from my original goal. So now I'm trying to reign in my expectations and get back to basics.

All my options are assuming I will purchase the following S/C setup (prices include shipping.) I would be willing to pick up a used kit if it saved me some money, but it looks like they are hard to come by and get scooped up pretty fast.
  • Complete Vortech V-3 kit w/ fuel components: $4,265
  • CX Racing Front-Mount Intercooloer: $525
  • Battery relocation kit: $300
  • Total: $5,090
A clean 99-04 GT with 150k-175k miles goes for about $3.500 in my area.

Option 1: Boost a High Mileage Engine - $8,600
I don't love this option, but it's the most simple and least expensive, so it must be considered. I know these engines are supposed to run for a long time, but throwing 8-9 lbs of boost at a engine with 175k miles seems like a quick way to wind up on the side of the road. Any previous experience in the area would be greatly appreciated.

Option 2: Swap a Re-manufactured Engine Into a GT w/ Bent Valve - $9,500
I may have an opportunity to buy a GT with bent valve for $1500-$2000, but I'm concerned the block may be damaged. However, considering that it has a brand new clutch, 78mm TB and catback exhaust, it could be a great deal. A remanufactured engine from accurate engine costs $2,400 shipped (w/ core.) The engine is warrantied to 100k miles, but I'm certain that warranty is void after adding a supercharger. This option seems solid, but if it blows up, I'm SOL.

Option 3: Build a Forged Engine Using GT w/ Bent Valve - $11,800
Similar to option 2, but I pay a shop to build a forged block and recondition the heads. A local shop quoted $4,700 for parts, assembly, balancing and 3-year/100k warranty (still valid with S/C installed). It's a bit more than I want to spend, but it seems to be the safest route. However, for that price, I could go through two re-manufactured engines.

Miscellaneous Questions:
  • Since the car is high mileage, what other items should I plan on replacing? Suspension would be on the short list for me, and maybe a T56 down the road, but can everything else be expected to last deep into the 200k mile range?
  • How difficult is it to get all of this insured at its real value, and how bad does that affect premiums? Is one insurance company better than others for this type of custom underwriting?
I know it's a lot of questions, but I greatly appreciate any input. My apologies to the mods if this is too much for the intro section.
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While looking for my GT I found some already supercharged etc ones for under 10K and they were quite nice but I decided on stock. These cars had receipts showing much more than 10K in them and that didn't include the necessary dyno tuning etc. No matter how hard you try to keep in budget it usually goes south or you end up cutting corners is what these guys said who did it. I would look for one of these. Patience is best as I looked for over 6 months to find mine. The bent valve sounds cheap but is it drivable enough to check out the trans and rear end?
I would go with door number one if not buying an already
completed car and bank the money left over and add to it as you drive for a rebuild later. Doing this gives you the opportunity to sort the car out and fix all of those little things that come up on an older car too. A lot depends on how you drive the car on how long it lasts.
My experience with insurance is the cost to insure it for how much you have in it is cost prohibitive. Most OP buy the car back from the insurance company and strip it if wrecked. Stolen could be a bummer though if not recovered.
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Interestingly enough, I talked with a guy today that's selling his '00 GT with forged internals, Paxton Novi 2000 and a long list of mods. He's only asking $9,250, but unfortunately I don't just want to have a fast car, I want to build a fast car. I did a little more research and it looks like I wouldn't be the first one to boost a 4.6 2v with 150k+ miles on it, so maybe I'll go that route and just budget for a rebuild down the road. Thanks for your input, I'll update when I make a decision!
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Stock motor will support your 400rwhp goal if budget is a concern. I wouldnt be scared of the mileage in the 100k range if the car is well maintained.

My car has a stock shortblock and weighs 3300lbs full weight - giving it a hp and weight advantage over the vast majority of N/A bolton new mustangs / camaros / etc.

Building a car takes time and money. If the budget cant afford the entirety then buy the best possible parts within your budget so that you dont have to do things twice and so that each part complements your plan. For your budget I would go with option 1.
-Spend the money on good fuel components (buy with your future goals in mind).
-Spend the money on the type of forced induction you want to drive (dont just buy the cheapest - buy the one you like and you can afford).
-look at better brands of intercooler. Cxracing is cheap at the sacrifice of some efficiency.

Buying an already built car will save you a ton of money - but make sure it is built the way you like it and that it doesnt have any issues.
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Thanks man. I'm growing more on option 1 as well, especially after seeing a few other threads of people boosting motors and rolling over 200k miles. These mod motors are impressively durable.

I actually just got back from putting a deposit down on an '03 GT convertible with a hair under 150k on it. It drives extremely smooth, paint is in great condition, has documented oil changes every 3-6 months, and has a new clutch and short throw shifter. I'll be paying $3,500 out the door, so I definitely feel like I got a good deal. I know that I'll end up spending more on the car over time, but I didn't want to spend more than 10k on power alone, because I know all the little mods will add up.

To save on money, I might opt for a used s/c kit. After watching the classifieds more closely I should be able to get a s/c kit for $2,500-$3,000 with a little patience. After a good tune, I should still be under $7k. If I feel like I need more power, I'll probably just order an mmr600 shortblock. That would put me a hair over $10k for 500whp. Sign me up!

I might start a build thread soon, but I think I have my plans in place. Thanks so much for both of your help. Rep'd!
Ford threw these motors in everything from Taxi's and police cars to trucks and transport vehicles. Why? Because they are stout motors that can endure a lot of wear-and-tear. 400rwhp is feasible on a stock motor as long as it is tuned correctly. As far as how to get there, avoid buying new. Join eveery single mustang-related page on facebook and check ebay frequently. I bought a complete Procharger D1SC kit (from blower to intercooler to TB, injectors, Diablo MAFia, boost-a-pump, etc) for $3K off ebay.

I made my own upgrades for peace-of-mind: Stock iron block decked and honed, stock crank, MMR rods and pistons, ARP fasteners, upgraded fuel pump, 60lb injectors, and SCT BA5000 MAF. With the machining, new parts, used blower kit.....I dont think I surpassed $8K. The only thing out of all that crap that you'll need is a stronger fuel pump, injectors, and an MAF. Lightning 90mm MAFs are cheap and will suffice.

I made 420rwhp/415rwtq at only 8psi with bone stock TB/plenum/plastic intake/heads,cams......through an automatic. I will also urge you to swap out the stock oil pump gears to billet gears. I made the mistake of reusing the stock oil pump and it could not hand the power/load while at the track and I lost the motor.
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