634 ratings
Big Oil - How To Get The Right Engine (Step By Step).
By =[T$CElite]= Damy!  /LASTBULLET
Hi there guys as we saw many players don't know how to get the right engine yet, so i made this step by step guide to help you out to get the right engine and also get the achievement Dr. Fantastic.
Day 1: "List Of Different Intels."
On DAY 1 you can retrieve differents intels, but you must be fast otherwise there are gonna burn them.
This are the differetns intels:

1) Airplane Keys:
This would help you escape fast once the engine is checked and it's the right one you can escape in this airplane without waiting for the helicopter.

2) Keycard:
With this you can open one of three doors to find the server room avoiding using the drill or ECM.

3) Shutters Codes:
With this you will able to set or open all the shutters so you will be able to see if the server room are behind any shutters and in case you start an assault this will give you more cover.

4) Blueprints:
A little map of the house. In case you don't know the map will be useful.

5) Fusion Research:
I still don't know how exactly this works, but some people says that this help to figured out which gas the reactor uses.

6) Guard Intel:
This intel shows you how the Guards looks like in Day 2.

7) Scientist Intel:
This intel shows you how the Scientist looks like in Day 2.
Day 2: "Find The Correct Engine."
In this day you will have to get inside the house, find the server room where could be located behind one of three doors, override the system to open laboratory door and then you have to go downstairs to the laboratory to find the correct engine.
Below are the steps to get the right engine and also "Dr. Fantastic" achievement if you don't have it yet.

Enjoy it.
Step 1: "Type Of Gas In The Reactor."
There are 3 types of gases that you may find: Helium (Green), Deterium (Blue) and Nitrogen (Yellow). You may find out what kind of gas is needed by finding a Note inside the house. Once you know what type of gas is needed go to the blackboard which is down in the lab there you will know what color is the reactor.


1) Nitrogen:

2) Deterium:

3) Helium:
Step 2: "How Many Cables Are Connected To The Blue Tank Of Hydrogen."
As you know each reactor has a blue tank of Hydrogen connected to it, so here is the way of knowing how many wires must be connected to this tank. Inside the house you can find a second NOTE. Once you have that note you should already know what color the tank is and now how many cables are connected to the blue tank of hydrogen.


1) In this example:


2) In this example:

"2x H"

3) In this example:

"3x H"

Step 3: "Find The PSI Pressure."
The last step is to find how much PSI those the reactor meter have and this is the way to find out. In the laboratory there are several computers one of them has a PSI Number, you MUST calculate the amount of PSI you should have in the reactor meter by using the follow equation:
(X / 10) * 0.7 = BAR amount or X * 0.07 = BAR amount

PSI Number on the computer, Example, Calculation & Explanation:

The correct pressure on our engine meter (by using the example above):

Important: PSI number on the computer could be different sometimes (but always result is close to 400) also the symbols of bigger, bigger or equal, smaller and smaller or equal too. So more important thing to look is the symbol.
Escape & Alternative Escape.
After they checked if it's the right engine, you will be able to escape. They two different escapes.

Normal Escape:
You will have to wait for about 2 minutes untill the hellicopter arrives.

Alternative Escape:
If you get the Airplane Keys (mentioned on Day 1: "List Of Differents Intels"), you can escape after delivering the correct engine, using the airplane in the road.
  • 1) Find the first note and see what color the reactor is.
  • 2) Find the second note and know how many wires are connected to the blue hydrogen tank from the connected reactor.
  • 3) Calculate the amount of PSI and find this result in our reactor meter.

Important & Helpful Stuff
Sometimes some notes may not spawn or lab computers can be shutdown, but stay calm, we can still
find out which is the correct reactor and finish the mission.

These are the possible alternatives:

  • 1) If the note in step 1 appears, the note in step 2 also and computers are off, just look for the color of reactor and the number of cables connected to the blue hydrogen tank. Since there will be no two alike.

  • 2) If the note in step 1 appears, the note in step 2 does not appear, but the computers are ON, then only seek the correct color of the reactor and the amount of PSI which must have the meter in the reactor.

  • 3) If the note in step 1 doesnt appear, and Note 2 appears and computers are ON, just look at the reactors with amount of cable that note 2 shows and the amount of PSI you should have in the meter in the reactor.
< >
=[T$CElite]= Damy!  /LASTBULLET  [author] 6 hours ago 
@[FÜM] [<{RGC}>] Sabaton4Ever - Thank you, im glad to help payday community!
Very good Tutorial! It has really helped me and my mates to get the right engine. Thank you and have a nice day. ;)
=[T$CElite]= Damy!  /LASTBULLET  [author] Mar 26 @ 5:40pm 
@Private Vice - Add me and invite me to join once you are on the day 2 and i'll get it at the first try. Also i can explain it to you ingame.
Private Vice Mar 26 @ 5:37pm 
I didn't make a mistake. I also had my friends all read it, interpret it in their own way and also try it. Same result.
=[T$CElite]= Damy!  /LASTBULLET  [author] Mar 26 @ 5:22pm 
@Private Vice - You're doing something wrong definetly, invite me to join once you are in day 2. And you will see you're making a mistake.
Private Vice Mar 26 @ 5:17pm 
Still doesn't seem to work. I tried this exact method three times, different difficulties, same map. No dice. I took the one that matched all the specifications, and it was wrong. I took one that hardly matchs any of the criteria, and it was the correct one.
=[T$CElite]= Damy!  /LASTBULLET  [author] Mar 26 @ 5:00pm 
@Private Vice - Of course everytime it's totally different, but it's pretty easy once you get the process!
Private Vice Mar 26 @ 4:44pm 
I've tried every method possible to determine the correct engine. It honestly just comes down to dumb luck half the time because it constantly seems to change the criteria.
=[T$CElite]= Damy!  /LASTBULLET  [author] Mar 19 @ 11:05am 
@Miceweasel - Yes you can stealth the whole mission, till the chopper arrives.
Miceweasel Mar 19 @ 12:57am 
The paper on the table doesn't look like that. Failed the mission >.<
Also, is it even possible to stealth it? Police was alerted when they saw basement door was open.