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Need help with modified used GT purchase

robvas

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Hey everyone, had a quick question about an early 2015 mustang GT premium that I may pull the trigger on. It's used with about 55k on the odometer. I'm not new to the mustang world, but I am new to the Gen 2 GT world and was wondering if anyone would have any issues with the below modifications. It's a 2 owner car, clean carfax, but the dealer has no other info on who did the mods or tuned it etc. Thanks for any help.

ROUSH Phase 2 Supercharger Kit Includes:
ROUSH TVS R2300 Supercharger
ROUSH Low-Restriction Air Filter Induction System
ROUSH Large Aluminum Intercooler
ROUSH High-Flow Fuel Injectors
ROUSH 60mm Dual-Bore Throttle Body
ROUSH Custom Designed Heavy-Duty FEAD System
Higher Boost 80mm Pulley
High Performance Spark Plugs
BBK Performance Exhaust
American Racing (Style: AR920) Wheels
Custom Suede Flat-Bottom Steering Wheel
Carbon Fiber Shift Knob w/ Carbon Fiber Boot Trim
Nice setup. Make sure you get the tuning device that was included so you don't get stuck not being able to modify the car or return it to stock

have the car compression tested and inspected before you buy
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ZLwhat

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Nice setup. Make sure you get the tuning device that was included so you don't get stuck not being able to modify the car or return it to stock

have the car compression tested and inspected before you buy
I'd assume if they don't know the backstory on the installs the dealership also won't have the tuning device. Is this something a good tuning shop will be able to remedy if I didn't have the tuning device?
 

robvas

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I'd assume if they don't know the backstory on the installs the dealership also won't have the tuning device. Is this something a good tuning shop will be able to remedy if I didn't have the tuning device?
You can get it fixed but sometimes it a huge pain in the ass to get the computer unlocked etc

you shouldn't need to do it but if you ever want the car retuned or if the dealer stupidly flashes it back to stock etc

it's possible if the dealer reflashed it you don't need the original device I'm forgetting exactly how those tubes were delivered
 

DefaultDriver1

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Have a mechanical pre purchase inspection including a compression test done before you buy it. If sound negotiate the best price possible and then buy it. Sounds like a high quality build to me.
 

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The worst thing about buying a modified car is not knowing its backstory or the mods it had that may have been removed. The description doesn't tell the whole story. I've lost count of how many stories I've heard where the car ran like crap because it had a ton of mods and a tune, then all the mods were removed before the sale but the tune left as is and the device was nowhere to be found.
 

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ZLwhat

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The worst thing about buying a modified car is not knowing its backstory or the mods it had that may have been removed. The description doesn't tell the whole story. I've lost count of how many stories I've heard where the car ran like crap because it had a ton of mods and a tune, then all the mods were removed before the sale but the tune left as is and the device was nowhere to be found.
Or it could run and work well, who knows, I'll know more after i drive it and have it inspected. On a two owner car with this low of miles I'd be surprised if it was abused, any used car for that matter would be a bad buy if we worried about every little thing haha
 

AZ_Ryan

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Stay away from that car. Never, ever, buy a heavily modded S550 from a used car dealer. You are asking for trouble.
 
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coyote550

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Or it could run and work well, who knows, I'll know more after i drive it and have it inspected. On a two owner car with this low of miles I'd be surprised if it was abused, any used car for that matter would be a bad buy if we worried about every little thing haha
It absolutely could but its always toss up. If its a seasonal/weekend car that you're willing to work on, I'd definitely consider it. If you're buying this as a daily car I'd probably reconsider. Just my 2 cents.
 

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Stay away from that car. Never, ever, by a heavily modded S550 from a used car dealer. You are asking for trouble.
Some people need to learn the hard way.
 

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ZLwhat

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Ok ok fellas, this thread seems to be a mix of a lot of buy it don't buy it lol....no need to be negative was just curious on everyones opinions.
 
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ZLwhat

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It absolutely could but its always toss up. If its a seasonal/weekend car that you're willing to work on, I'd definitely consider it. If you're buying this as a daily car I'd probably reconsider. Just my 2 cents.
Could you please elaborate on what would be a major issue arising that would need to be worked on immediately if it's a sound and well built car....everyone keeps anticipating i'll need to wrench on it from day one...just wanted to get an idea of what that would entail...not that i couldn't just wouldn't want to do a straight engine swap the day after purchase.
 

robvas

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Could you please elaborate on what would be a major issue arising that would need to be worked on immediately if it's a sound and well built car....everyone keeps anticipating i'll need to wrench on it from day one...just wanted to get an idea of what that would entail...not that i couldn't just wouldn't want to do a straight engine swap the day after purchase.
Buying any used car can be a gamble. Buying a forced induction used car can be even more of a gamble.

Your worst case here is the engine or transmission is hurt. Then you're looking at $10,000 in repairs out of the gate.

Another bad situation you could see, is the car doesn't run well at all. Idles rough, stalls, backfires under throttle...stuff caused by a bad tune, incorrect parts installation....

Both of which you can quickly rule out by a test drive, inspection, etc

What you have on your side is this may possibly be a Roush kit installed and the Roush tune loaded. This should be a fairly well running car in that case.

This compared to a random shop or owner installing who knows what and being tuned by who knows what.

I have had a couple supercharged cars, Whipple, Paxton, Vortech, and have a pretty good idea at what I'm looking at and how the car should behave. I would feel confident checking the car out myself and deciding if this was good to go.

the internet, you're going to to get a lot of opinions from people who haven't owned them and don't really know anything about them, and think any used Mustang as just used to do donuts and 1/4 mile rips. Again, this is where an inspection from a knowledgeable person comes in.

Get the car up in the air, look for signs of both maintenance and abuse, datalog the car and check the timing, compression test, make sure the transmission shifts as it should, engine operates smoothly through the RPM range....

Best case, you get a good deal on a car that has $10,000 in modifications already installed!
 

coyote550

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Could you please elaborate on what would be a major issue arising that would need to be worked on immediately if it's a sound and well built car....everyone keeps anticipating i'll need to wrench on it from day one...just wanted to get an idea of what that would entail...not that i couldn't just wouldn't want to do a straight engine swap the day after purchase.

Here's how I see it. If I did all of these mods on the car, and invested so much of my time and money in it, it would be my baby. If I was to sell it, I would sell it to a person who is interested in the platform, understands these mods, and will take good care of the car for years to come. If you sell your "baby" to a dealership, you're just trying to get rid of it. Its like leaving a child with a babysitter and running away forever lol. This tells me, that the last owner was maybe having issues that he was not willing to deal with, got rid of the car just to get something else that is more reliable. The flip side is that maybe someone who wanted something newer traded it in however I'm more inclined to think the former.

In either event, there are things that usually need to be done before going forced induction. Things such as the oil pump gear, crank gear, timing tensioners and etc if you actually care about your engine. Its impossible to know if it was done without pulling the timing cover off. Second is the transmission. Usually, if the car is a 6spd which I assume it is, people will change the clutch and throwout bearing when going with forced induction. Also cannot tell if this was done and in what condition the clutch and flywheel is. That right there could set you back 2k on the spot. If the car has drag radials, it was probably raced. A lot. The transmission could be on its last leg. That is just the beginning of it.

You seem to lean towards pulling the trigger. I know 700+hp is enticing but if you will do it, make sure you drive the car and have someone look at it. I mean check all fluids, boroscope the cylinders, check compression, check the flywheel and clutch, and whatever else he/she can come up with.
 
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Bikeman315

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Could you please elaborate on what would be a major issue arising that would need to be worked on immediately if it's a sound and well built car....everyone keeps anticipating i'll need to wrench on it from day one...just wanted to get an idea of what that would entail...not that i couldn't just wouldn't want to do a straight engine swap the day after purchase.
We are not being negative, we are being realistic. You are considering a 10 year old highly modified performance car. From some of your comments I'm not sure you understand the consequences of making this purchase. Yes, the car could be a dream car. It could be a real gem. On the other hand it could be a total disaster. The odds are for the latter but only you can determine that. Do your due diligence and make the choice. Let us know if you decide to buy it. Good luck!
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