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Old 03-22-2008, 06:51 PM   #1
BlackEclipse
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2G Spyder - FWD To AWD Conversion

2G (1995 – 1999) Eclipse/Talon FWD to AWD Conversion
by Jay Curcillo

This guide is intended to show you how to convert any 1995-1999 front wheel drive Eclipse or Talon 4G63T engine based car from front wheel drive (FWD) to all wheel drive (AWD). It will not work for 420A engine based non-turbo models. For my application I have converted a 1998 GS-T Spyder. Please read this through before buying any parts.

Before you even think about starting this project there are a few things to consider.

Do you have the money?

I paid $1500 to a guy that worked at a local junk yard for all of the parts from a 95 TSi AWD donor car. He removed them from the car, cleaned them with a sand blaster, and delivered them to my door. I thought it was a pretty good deal. You may or may not be able to come close to that price. If you can: great! However, you will end up missing parts here and there. I did. I ended up spending an extra $200 just to get missing parts such as a transmission mount, drive shaft bushings, fuel pump wiring harness, fuel filler neck, and many nuts and bolts. I recommend buying a junk donor car instead. Maybe find one with a blown engine or that has been wrecked. If it is wrecked, be sure none of the rear suspension was damaged. Lastly, is the exhaust. If I know DSMer’s, I know you are going to want some power. Therefore you will not be using the stock AWD exhaust (however you can, temporarily) and you can’t use that 3” exhaust off of your FWD. Tack on another $600 for an exhaust system.


Do you have the knowledge, skill, and tools?

You cannot do this project with basic knowledge and hand tools. If you haven’t worked with fuel systems, drive trains, suspensions, brakes, electrical, welding, and fabrication, then do not attempt this conversion. There is quite a bit of cutting, fabricating, and welding of the chassis. If you don’t have a MIG welder and a garage full of tools, then you will need to find them. My welding ability is pretty limited but I managed. The metal being welded for this project is only sheet metal so it is pretty easy to weld. If you don’t have welding experience, be sure to get help from a person who has. Impact tools, air or electric driven, are almost a must for this project. Going back to money, there are many tools you may need to purchase along the way. It all depends on what you will run into.


Do you have the time?

You may have read that some guys have done this conversion in one weekend. While that is possible, I don’t recommend it. You are considering major modification to your car. This project isn’t something to be taken lightly. To ensure everything is done correctly, I recommend allotting yourself at least a month to complete it. I put about 72 hours into this project. Theoretically, if you worked 12 hours a day, you could complete the project in 6 days. However I don’t recommend doing so. Take your time. Don’t rush this project.


Do you have the patience?

This project can be very frustrating at times. You may break bolts or tools and even become stuck at some point with no idea where to go. I found myself lying under my car cursing at the top of my lungs many times. Be patient and use the resourses listed below. It will all pay off in the end.


Resources:
www.dsmtuners.com
www.dsmtalk.com
www.columbusdsm.com
www.autozone.com (They have a limited on-line repair manual with pictures and diagrams.)


Parts needed

1. Entire 2G AWD rear sub-frame (Including the large bushings that bolt between the sub-frame and the unibody.)
2. Sub-frame Bolts (These bolts hold the sub-frame to the unibody. The FWD bolts are shorter. You will need to cut a square out of the sheet metal above each bolt in order to get the AWD bolts out of the donor car.)
3. Rear suspension set up (Including ABS Knuckles (if applicable), sway bar, control arms, shocks, and springs. You may use the FWD shocks and springs, but they are a different spring rate.)
4. E-Brake cables
5. Rear differential
6. AWD Front and rear axles (Splines must match transmission and differential. If you have ABS these must be ABS axles.)
7. Drive shaft with mount brackets, bushings, spacers, washers, and nuts.
8. Drive shaft frame hangers (These must be cut out of the tunnel of the donor car then welded in place on the project car.)
9. Transfer case (Input shaft splines must match transmission)
10. AWD transmission
11. AWD 7 Bolt Flywheel (It is smaller than the FWD flywheel. 6 bolt conversions will need a 6 bolt flywheel.)
12. AWD exhaust (I just upgraded to a 3” turbo back.)
13. AWD exhaust hangers
14. Fuel filler neck (Be sure to get the fuel filler neck that matches the fuel tank from the donor car. 1995-97 differs from 1998-99.)
15. AWD fuel tank (Be sure to get fuel pump assembly and level sending assembly.)
16. AWD fuel tank straps and shield
17. AWD fuel pump wire harness (At least the connectors for the fuel pump and level sending unit.)

I’m sure I left some little parts out. This is why I recommend buying a donor car. You never know what else you may need.



Let’s Get Started


Here is a comparison of the FWD to AWD rear end.



If your car has antilock brakes (ABS), and you wish to retain them, you will need to get your parts from a car with ABS.


Front and Rear ABS Axles and Sensors



Be sure to get all parts needed in good condition. The insulators used on the drive shaft brackets pictured below
are made of rubber and will break down over time. You may want to order new ones from the dealer.



AWD Donor Car Parts Removal

I will assume you bought an AWD donor car and need to remove all parts from it. First raise the rear of the car as high as safely possible. This will allow you to remove the sub-frame with all suspension and rear drive train still in place. Remember to remove the e-brake cables so you can bolt them into the FWD chassis. They have been cut in this picture, but if left in tacked they will bolt right up.


AWD rear sub-frame with suspension and drive train.



Be sure to get the sub-frame bushings.



Once you have lowered the AWD sub-frame, suspension, and drive train with a sturdy jack you are ready to remove the AWD gas tank. Remove the tank shield first. Then unbolt the tank straps. Lower the tank slowly as you remove any fuel and evap system hoses as well as wire harness connections. Don’t forget to use the filler neck off the donor car. I needed one because my car was a 98 and I was using a 95 fuel tank.


AWD Gas Tank.


Now it is time to cut the drive shaft hangers off of the chassis. There are two of them. One is near the fuel tank, the other near the O2 sensor. You will need to remove the drive shaft first. Then drill out all factory spot welds holding the hangers to the chassis. To make it easier you can get a spot weld drill from your local hardware store.


Rear Hanger



Front Hangers. FWD bracket top. AWD bracket bottom.


Next are the bolts that hold the sub-frame to the chassis. You will need to cut down through the trunk or back seat to get them. For our application we will only need two of them as we will reuse two of the FWD bolts.


Here is a comparison of the bolts.


Cut the wire harness just before the AWD fuel pump connector. You will need to wire this into the FWD wire harness.


AWD fuel pump connector.



FWD fuel pump connector.


The last parts you will need from the AWD donor car are the front drive train parts. If you have ever changed a clutch you shouldn’t have any problem with this. The hardest part to remove on the front will be the axles. They may be frozen inside of the knuckle. Spray them with a generous amount of PB Blaster and rent an axle removal tool from you local auto parts store. I rented one from Advance Auto Parts for free (There is a steep deposit, but you will get that back if you return the tool in tacked). Once the axles are removed you can drop the transfer case and remove the transmission. First drain the fluids from the transmission and transfer case. Then support the engine block. Do not support the engine on the oil pan. You will crush it and cause the oil pickup to starve the engine of oil. Once supported properly you may remove the transmission mounts and unbolt it from the block. I used a motorcycle jack to lower the transmission, but a transmission jack works much better.


Here is a diagram of the front drive train parts.



Swapping the Rear End

Now that you have all of the main parts you need it is time to start on the FWD chassis. The rear end is removed in the same manner as the AWD rear end. Just raise the car up and unbolt the sub-frame with suspension parts still attached. Then drop the gas tank. On the 1998-99 model cars there is a system of complicated hoses for the evap system. These will be removed as your AWD tank may not have connections for them.


FWD chassis without sub-frame, suspension, or gas tank.


You will only need to drill out the front hangers from under the FWD chassis. It has no rear hanger since there is no drive shaft to bolt up.


Front Hangers. AWD left. FWD right.


Once the front bracket is removed, prep the under body for welding in the AWD bracket. I used a wire brush wheel to clean the surface. Then I taped off the areas that would be welded to and sprayed it with under body paint to deter rust. Last, I welded the hanger in place and spray the whole thing with under body paint. Be sure to weld the bracket in the exact location of the old one.


Under chassis prepped with under body paint.



AWD bracket welded to FWD chassis.


Next you can weld the rear hanger in place. Before you go welding the hanger any old place, I recommend temporarily bolting up the drive shaft for measurement. You will regret it if you have to remove the bracket after welding it in the wrong place.


Rear bracket and new bolts for AWD gas tank.


Before you bolt up the gas tank you will need to drop the AWD bolts down through the FWD chassis. This requires a little cutting and welding. Start in the trunk. Remove all trunk carpet, plastics, and spare tire. You will need to cut in two locations (refer to picture). The passenger side is fairly easy. You need to cut just behind where the cross bar support attaches to the chassis. The driver side is a little more involved. You will need to cut the cross bar support out to access this bolt. This all gets welded back in place when done. I welded plates over the holes and painted everything when done.


Passenger side rear bolt hole.



Driver side rear bolt hole with cross bar removed.



Driver side rear bolt hole. Metal plate to be weld over the hole on left.


Save the FWD bolt you just removed from the rear. These are used in our next step. The front mounting points for the AWD sub-frame are farther forward on the chassis than the FWD mount points. Since you don’t need the FWD forward mounting bolt (seen on the right in the picture below) you can cut it flush with the chassis.


FWD forward sub-frame mounting bolt seen right.


The AWD forward mounting point will need to be cut out of the FWD chassis. Non-Spyder owner won’t have much problem here. You can just cut down through the back seat much like we did in the trunk. Spyder owner will however have a problem getting to that area as there is a large seat reinforcement covering that location.


Non-Spyder owner cut down through back seat.



Spyder back seat reinforcement.


I decided to cut my access hole from under the car. Using a hole-saw I drilled from inside the frame. It may be easier to drill from the wheel well, however I thought it would be more exposed to debris and would rust faster. After this hole is cut drop the FWD bolt taken from the rear in place. I welded washers onto my bolts for reinforcement.


Cut hole in frame for bolt



Bolt with welded washer cut so it will not turn in the frame.



Once the bolts are in place I recommend spot welding them. If you don’t the bolts may still turn in the chassis. I fabricated some plate that would hold the bolts down at the same time, but the bolts still turned on me and I had to cut the chassis open again and weld the bolts down. Be sure to spray them with some paint when finished.


Fabricated bolt plates.


Some people may prefer to cut out side in from the wheel well. Here is an example of that. Note the shape of the access hole. This makes it much easier to drop the bolt through while avoiding the reinforcement inside the frame.


Wheel well cut.


Now that the bolts are in you can install the AWD gas tank. First you must remove the old FWD gas tank brackets. You can remove them by drilling out the spot welds. Once they are gone you will need to drop new bolts down through the chassis to hole the AWD gas tank straps. You may need to cut holes to get the forward bolts in place. I used magnetic extension to maneuver the rear bolts.


FWD gas tank hangers.



New AWD gas tank strap bolts.


Install the gas tank. While you lift the tank into place you may want to maneuver the evap hose and ABS wire harness. Bolt the tank straps into place and install the tank shield. Be sure to connect the filler neck and pressure line because it is just about impossible to get to once the sub-frame is installed. If your car is a 1998-99 and you are installing a 1995-97 fuel tank you will need to use the fuel filler neck from the donor car. Why? Because the filler neck on the 1995-1997 has a larger pressure relief hose going to the top of the filler neck. If you don’t use the donor car’s filler neck fuel will rush out of the top when you go to fill the tank at the pump.


AWD gas tank installed.


With the fuel tank in place you can now wire in the fuel pump, level sending unit, ABS wires, and evap purge solenoid. The FWD fuel tank has only one level sending unit located in the middle of the tank. On the other hand the AWD tank has two level sending units on either side of the tank. The AWD units are half the ohms of the FWD unit. This is why the AWD units must be wired in series. Follow the diagram below in order to wire the fuel pump and fuel level sending unit.


Fuel pump wire diagram.


On the 1998-1999 gas tank there is a solenoid at the back of the tank and sensor on the fuel pump assembly. Wiring the solenoid and sensor may be optional. I wired one, but not the other and haven’t received a check engine light. You will however want to splice into the ABS if you have this option. These wires will connect according to color. Connect the ABS, and evap purge solenoid to the corresponding colored wires. I just hid the solenoid behind the plastics under the rear speaker. You may here it click when you start the car.


Evap purge solenoid.


Now you can bolt up the rear end. Jack the sub-frame into place and bolt it up. Secure the suspension and connect the ABS wire harness. Be sure to install the sub-frame bushings. Remember, you are putting a different sub-frame and suspension in your car so you will want to get an alignment done once you have completed the project. While the parts are the same, the AWD parts have been adjusted for another chassis. They will need adjusted for your chassis.


Sub-frame bushing.



Rear sub-frame installed with 3” turbo back exhaust.



Swapping the Front End

The AWD transmission is installed in the opposite order that it was removed from the donor car. There are a few things to take into consideration. If you had ABS you will need to install ABS axles. The splines on the axles must match the splines on the transmission. The same goes for your transfer case. The splines on the transfer case must match the output shaft on the transmission. You must install an AWD flywheel because it is smaller than the FWD flywheel. If you are lucky enough to have the shield that covers the opening at he bottom of the transmission, great. If not you can cut your FWD shield to work with the transfer case.


ACT 2100 mounted to AWD flywheel.



Cut FWD shield along yellow line to fit with transfer case.


The driver-side axle has a carrier bearing that bolts to the back of the block. One of the bolts runs through the AC pump bracket. You will need to use a bolt long enough to go through both brackets.


Axle carrier bearing bracket.



AWD transmission and torque specs.



Transfer case torque specs.


Now that your car is AWD you may want to display some sort of badge that says so. Just in case it gets towed. I was going to get the GSX sticker from the dealer, but I was told it is discontinued. You may be able to stop in at a local sign shop and have them make you a GSX or AWD sticker. I did however find this nice little company online at www.speedysigns.com. You can design your own stickers with their automated system. It works very well and the sticker came out real nice not to mention the good price. Just use the font and sizes shown below.


OLD HTML VERSION = http://www.columbusdsm.com/SAWDC/2G_...Conversion.htm
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Last edited by BlackEclipse; 03-25-2008 at 07:05 PM.
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Old 06-15-2008, 01:30 PM   #2
JayC
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Link to VFaq.

http://www.vfaq.com/mods/2G_FWD_to_AWD_Conversion.htm
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