2.0 FAQ
by: Mr. Efficiency (Tyrin) and Labora
First the basics:
The 2.0 8 valve SOHC made in Brazil was first introduced in the sunbird, and only the sunbird, when the J platform was first introduced in 1982, and later in 84 a turbo version was introduced that was only available in the Sunbird GT that had a water cooled t-25 turbo that produced 9 pounds of boost but it only lasted until 1990 due to many mechanical flaws and its unreliability, which isn’t so bad if you take care of it properly. The 2.0 and 2.0 turbo better known as the LT3 both went through many changes year to year mostly dealing with oil journals size, and a bunch of different cams, from 84 until 91. In 1982 they were carbureted and later in 83 changed to throttle body injection (TBI) there were two kinds of throttle bodies for this engine from 83 - 86 they had a model 300 throttle body and then from 87 – 90 they had the model 700. Then they were switched over to multi port fuel injection (MPFI) in 1991 and with that change they removed the distributor and had coil packs used instead. Then in 95 when the Sunbird was killed the engine went off the J platform with the car, but is still produced as a DOHC version in Daewoo's. The block is cast iron and has nodular cast iron crankshaft and connecting rods, the turbocharger is a T25 water that provides 9 pounds of boost. And the engine is equipped with a knock sensor that protects the engine from detonation on regular or premium fuel, though premium is preferred and highly recommended for performance use. The car can go 0-60 in 7.2 seconds and does 15.40s in the 1/4 mile @ 91 mph.
Specs:
2.0 TBI NA (VIN K):
HP: 90-102 (heard many variations, I prefer to say 102 cause its highest)@5200 RPM
TQ: 130 @ 2800 RPM
Compression ratio: 8.8:1
Bore x Stroke: 3.38 x 3.38
Firing order: 1342
Intake valve size: 1.69"
Exhaust valve size: 1.44"
Cam: elevation = intake – exhaust: 0.2409 – 0.2409 for 1989
0.2366 – 0.2515 for 1990 – 1991
2.0 MPFI NA (VIN H):
HP: 111@5200 RPM
TQ: 125@3600 RPM
Compression ratio: 9.2:1
Bore x Stroke: 3.38 x 3.38
Firing order: 1342
Intake valve size: 1.69"
Exhaust valve size: 1.44"
Cam: elevation = intake – exhaust: 0.2626 – 0.2626 for 1992 – 1994
2.0 Turbo (VIN M) (engine code: C20GET):
HP: 165@5600 RPM
TQ: 160@2800 RPM
Compression ratio: 8.0:1
Bore x Stroke: 3.38 x 3.38
Firing order: 1342
Intake valve size: 1.69"
Exhaust valve size: 1.44"
Cam: elevation = intake – exhaust: 0.2409 – 0.2409 for 1989
0.2625 – 0.2625 for 1990
2.0 to 2.0 turbo:
This is probably the most often asked question ever when it comes to the 2.0 and so I guess it
makes since to put it on here
To change from a 2.0 to a 2.0 turbo is a lot of work and the easiest way to do it is just to swap
the motors over, cause the only things the two engines share are the block, crankshaft and the
connecting rods. But if for whatever reason you decide to keep your block in your car you need
to swap pistons cause the turbo pistons are forged and the 2.0 NA's are not, you need the turbo
head cause of the compression ratio change, (8.8:1 NA - 8.0:1 turbo) for those of you who think
its stupid to lower compression and gain power with a turbo.....trust me it works. You will also
need all the wiring, ECM, throttle cable, oil pan, intake, exhaust, turbo, down pipe, fuel pump
(unless your car was originally MPFI then its better than the turbo pump) and basically
everything attached to the head except the block, get a turbo head gasket when you get a new
one, obviously, lol and all the air box crap too if you wanna go stock. Transmission change is
also a good idea if it’s a 5 speed, see the "Transmission" section.
Transmission:
The best transmission is obvious for the 2.0, first off a 5 speed is always the way to go they are lighter and you don't lose about 30-35 percent of your power like an automatic and only around 10 percent through a 5spd, and that varies between clutches, so you can easily bring that percent down a little more. But the 5spds are hard to locate so if you have the auto transmission It shouldn’t be to bad unlike the 5spd you won't have to lift the throttle while the transmission shifts allowing the boost to not drop much and just like the 5spd you can always build up the auto with a stall or shift kit etc.
The 2.0 NA comes with an Izuzu trans which isn't very strong but some people have managed to run a "stock" 2.0 turbo on that trans with no problems. But once you start putting down some serious power it won't stand up to it, the Getrag 5 speed trans that comes in the 2.0 turbo is much stronger and can take 300 plus horse power, so there is not to much to worry about with that trans unless you start getting really serious, but a lot of people on the org have made it into the 13's on that trans so I think its the best you can get with out going out and having a hole trans completely rebuilt with all custom gears and everything, but that'll run you up around ten
to twenty thousand dollars or more, that may be a bit of an exaggeration, but you get the point. When you swap over the Getrag trans the drive shafts must be swapped to cause they are also stronger than the ones from the Izuzu trans.
Gear ratios:
HM-282 – Getrag 5 speed (RPO:MG2)
1st - 3.50
2nd - 2.05
3rd - 1.38
4th - 0.94
5th - 0.72
Final Drive Ratio - 3.61:1
TH125C (3T40) - 3 Speed Automatic (RPO: MD9)
1st - 2.84
2nd - 1.6
3rd - 1.0
Reverse - 2.067
Final Drive Ratio - 3.18
Isuzu 5 Speed Manual (RPO: MK7)
1st - 3.91
2nd - 2.18
3rd - 1.45
4th - 1.03
5th - 0.74
Isuzu 4 Speed Manual (RPO: M73) (1.8 trans)
1st - 4.01
2nd - 2.25
3rd - 1.40
4th - 1.00
Mods:
Here is a list of some mods you could do to your 2.0 turbo or NA to get a little more power out of it some of them are a little easier than others and some are just a lot of work, or a little harder to do.
1. The obvious route almost everyone is taking, go turbo.
2. A Cam from a MPFI 2.0 has a higher lift, which holds the valve open longer, ie: more fuel in the cylinder = more power.
3. T-3/T-4 turbo if you want to do it cheap you can get the turbo from a turbo SAAB, Volvo, Mustang and T-bird. You will of course have to redo you piping as well as have a exhaust manifold worked on.
4. See “Grand Am 2.0 turbo” (E-bay search this also for some parts).
5. Intercooler/BOV obvious but needed
6. Manual boost controller (See MBC at bottom links) for about 3 bucks.
7. MPFI swap you can keep your head but you need: injectors, fuel rail, wiring, ECM, throttle body, throttle cable, coil packs (the MPFI cars don’t have a distributor), cap for the end of the head were distributor is supposed to go.
8. If you have a 2.0 turbo put a MPFI throttle body on cause its bigger and bolts right on with little modification, a throttle body from a 2.8 Fiero is even better but requires a little fabrication work.
9. 3.1 radiator always helps to keep things cool, and its aluminum. Since one of the major design flaws of the 2.0 is a Head gasket going bad from overheating this is a good cheap upgrade just have to do a few custom hoses which can be done cheaply.
10. DOHC head swap. See below
11. A check valve or two in the line up to the map sensor to stop the ECM from limiting boost.
12. Water/methanol injection. (See the links at the bottom)
DOHC head swap:
There are two versions of the 2.0 in the UK that are DOHC they are the C20XE which is 2.0 16V DOHC that has 156 horsepower, and in 92 there was a turbo version of it that had 204 horsepower and 205 TQ. The turbo version was called C20LET Both engines use the same block as all the 2.0 Sunbirds, so to swap to a 16 valve DOHC sunbird you need the head, timing belt, timing cover, all the wiring, ECM, intake, exhaust, fuel rail, injectors, etc, etc…… but now you know it is possible. The only problem is shipping from the UK will be really expensive and so will the hole top half of a motor from a fairly new car, but if you got the money why not try it. As far as I know it has yet to be done.
Problems:
Won’t start:
First check for spark by pulling a plug wire and sticking a screw driver in the end while someone cranks over the car if there’s sparks obviously you have spark, if not proceed to “spark”. If you have spark check for fuel by just looking into the throttle body if your TBI, if its carbureted you can just look to see if fuel is in the carb but if you cant just pull a fuel line to see if your getting fuel out of it when the car is being cranked, if your MPFI relive fuel pressure and pull a fuel line and see if gas come out while the car is being cranked over,(put the line in a bottle or something cause the fuel will come out of there pretty quick) make sure your not checking the return. If your getting gas then its ok if not go to “fuel pump”. And if you have gas and spark then there is no reason it shouldn’t start except air sometimes it won't start if the air intake is completely clogged but it very rare that happens. If it won't crank over check battery or starter, if both are good check wiring.
Fuel pump:
First be sure it’s plugged in, lol and make sure all the fuses are fine. But one thing you can do is look around your driver side strut tower around the wiring harness and there should be a single grey wire hanging lose with a plug on the end that's not plugged into anything. with the ignition key in the "run" position apply 12 volts of power to the end of the plug, and the fuel pump should come on, If it doesn’t that means there is a break in the wires somewhere between the fuel pump and the ignition or the relay. If the pump does work then that means the relay is gone, the relays are located on the passenger side behind the shock tower, there little black boxes with white numbers stamped on them, pull out the relays(only one is for the fuel pump) to find which one is for the fuel pump look at the wires that are going into the back of the relay , look for a pink wire with a black stripe on it and a grey wire, (they should be going into the same relay) these are the fuel pump wires pull the cap off the relay and find one piece of wire and strip the ends then put one end of it on the metal prong of the plug the grey wire is attached to and put the other end of the wire on the metal prong the pink/black wire is attached to, if you do this with the ignition in the run position and the fuel pump works, and you pull the wire off and the pump dies the relay is gone and that is your problem. If your still not getting gas flush the fuel lines to make sure there not clogged/plugged, also be sure your injectors are getting power on positive and they are properly grounded.
Spark:
If you have no spark first check all your plug wires, make sure there in good shape and all plugged in properly. Then check the coil and be sure it is getting power and distributing it as well, if none of that works check all your wiring into the coil and be sure its all properly grounded.
Random facts:
-Carbureted models have a mechanical fuel pump mounted on the block on the side facing the front of the car, TBI and MPFI cars have electric fuel pumps in the gas tank.
-The 2.0 turbo and the Getrag transmission were only available in the sunbird GT until 1990, the 2.0 turbo and the Getrag trans never came in any other J-body from the factory.
-From 82-85 the 2.0 came with E2SE carburetor.
-In 86 the 2.0 had a model 300 throttle body.
-From 87-91 the 2.0 had a model 700 throttle body.
-From 92-94 the 2.0 had multi port fuel injection (MPFI).
Info:
Almost all the info here I learned from nine months on the org and my Chiltons manuals (for specs)
http://www.c-speedracing.com/howto/mbc/mbc.php MBC
http://www.v6z24.com Mostly Z24 stuff, but there is some info on the 2.0 in there.
http://www.dawesdevices.com/water.html
