The 6m-gte Story


After having installed a pacesetter header and free-flowing exhaust on the Silver Supra I came to the conclusion that it just "sounded" faster than it really was. I wanted to return to the sweet sound I had before, but still have gobs of power.  Answer - the 6m-gte hybrid motor!
 
 

The 6m-ge motor as it appeared when it arrived from Watanabe. Note the hacked hoses and wiring.
 
 

Busted fan.
 
 

Clearly shows center dip oil pan with drain on the wrong side.
 
 

3000 on intake plenum and no EGR equipment. Note also lack of vacuum ports for EGR on throttle body.
 
 

Connectors too brittle to reuse anyway. Cosmoline (sp?) residue.
 
 

6m block as it appeared when it was returned from the machine shop, vatted and freshly painted.
 
 

Freshly polished 6m crankshaft. Barely visible is 6M letters cast into balance on #3 cylinder.
 
 

#8 Rotating assembly was fully balanced.
 

Closeup of crankshaft journals. Note 6M casting.
 

Doublechecking new bearing clearances with plastigauge.
 
 

A full set of custom-made pistons from Wiseco. Note ceramic-metallic coating on the tops.
 
 

Assembled block.
 
 

1.0mm HKS metal headgasket for 7m-gte matched to 6m cylinder head. Note ceramic coating in combustion chambers and on valves.
 
 

Note that when matched to block, one passageway on intake side (cooler side) is not used.
 

Fresh cylinder head mated to block. Note special black heat-stop ceramic coating in exhaust ports.
 
 

Easiest way to install fuel filter is to pull the engine out - just kidding. Intake ports not ceramic coated.
 
 

New water pump, timing belt tensioner. Also new 5m oil pump can be seen.
 
 

7m-gte exhaust manifold mated to the 6m engine. Note clearance ground out for power steering pump bracket.  I changed the color of the manifold from "Aluminum" to "NuCast" later using the same VHT brand paint.
 
 

Another view with 7m-gte manifold mated.
 
 

This shows dowel pin setting for intake advanced 3 deg and exhaust retarded 3 deg to remove valve overlap. Setting not recommended for N/A engine.  Later set back to stock because I did not like the slight lope at idle.
 
 

Timing belt installed.
 
 

Turbo mated to 6m engine.
 
 

1/8" NPT male to 1/8" MIP male was used to add a generic three-way T fitting for oil supply to the turbo.  The sending unit shown is actually the 6m unit as I hadn't pulled my 5m-ge from the car yet.  The 5/16" hose barb is later replaced with an invert flare fitting for a steel line which will ultimately be replaced with an AN fitting for a braided hose as I make refinements to the system.
 
 

Oil pan is modified to accept the bottom flange of the ct-26 oil return by drilling holes and welding in a threaded backing plate.
 
 

Note how much larger this hole is than the tiny threaded plug to the right that was actually provided for an oil cooler system.  The oil return from the turbo relies upon oil being able to drip freely from the turbo bearings.  Any restriction or backup at all would cause the oil to overheat at the bearing and "coke" ultimately leading to premature bearing failure.  The tiny threaded plug should not be used.
 
 

Pan baffles brazed back into place after backing plate welded in.
 

My first oil supply/return setup using a 7/8" reinforced hose with hose clamps and 5/16" copper line with compression fittings.  This worked a few months but developed a leak at the compression fitting the first time I had to r&r the turbo - live and learn. Ultimately I had some AN fittings welded to the flanges top and bottom and fabricated braided lines.  Not pictured here because I installed them after the engine was in the car.
 
 

Knowing that I would ultimately install a higher volume fuel pump, I drilled out the restrictor.  The restrictor is only crucial for limp mode in the event your fuel pressure regulator fails.
 
 

Assembled 6m-gte on stand. Left side view. I discovered before install that the 6m A/C bracket pictured here wouldn't carry the 5m compressor - darn it, this one's lighter aluminum.
 
 

Assembled 6m-gte on stand. Right side view.  Looks like it belongs there, don't it?
 
 

After pulling the 5m, I mounted the Cartech fuel pressure regulator on the inner fender well just where the fuel return line bent northward - perfect spot.  The black plate you see is where the MSD ignition components will later be mounted.  This was about the only location left under the hood but seemed perfect as it was right next to the ignitor and kept things neatly tucked away under the intake plenum.  Unfortunately, I discovered on a long trip across the Arizona desert that despite furnace grade insulation, the MSD equipment would still heat-soak and begin to miss.  Still looking for an alternative to this location or an alternative to MSD.
 
 


 

The MSD units mounted on the plate and wiring harness neatly done. Components include the MSD 6A, Boost Timing Master and HEI Tach Adapter.
 
 

Because after the engine is installed, it would require Houdini to service the MSD units, the mounting plate was made with hinges to facilitate swinging it an inch or so to allow access to the mounting bolts with an extension socket.
 
 

I had this junkyard A43DE transmission rebuilt by a local shop because I wanted a fresh tranny with my new motor.  There were no aftermarket performance mods readily available for the A4x series, so we just went with a quality rebuild kit and a 2400rpm stall converter (stock is 2100).  I am running Redline ATF and an auxilary transmission cooler.
 
 

Motor and transmission mated.
 
 

Just hangin' out!
 
 

Driver's perspective.
 
 

Installing motor. Note rear of car is elevated on jackstands for better approach angle.
 
 

Another view of motor installation.
 
 

Lower IC piping cut from 2" exhaust mandrel U sections, cut to fit and tack-welded. I later took them to a professional welder to finish it up and make it look pretty.
 
 

AFM to turbo intake pipe fabricated from a 3" and 2.75" nitrile elbows joined. Note hose barb for BOV.
 
 

Exploded view of intake pipe pieces. Nitrile is easily cut with an exacto knife.
 
 

Top to bottom: Custom upper IC hardpipe completed, 7m-gte hose section for turbo outlet, lower IC hardpipe turbo to IC, SAAB BOV and 1" hose with vacuum line.
 
 

Modified crossover shown installed with stock piece on top for comparo. Made by joining pieces or scap crossovers so both ends are the TB end.  After about a year, the glue separated and I then reinforced the joint using a thin sheet of aluminum glued to the inside surface of the housing.
 
 

2.5" custom downpipe made by a local shop. Unfortunately not mandrel but mabe that will come later.
 
 

6mgte installed. Note 1/2" hose to oil cap for extra crankcase ventilation. Eventually, that hose will go to a catch-can.
 
 

6mgte installed. I was really going for that made at the factory look.
 
 

Exhaust included a Magnaflow muffler and Catco hi-flow cat all at 2.5"
 
 

Had to drop the fuel tank to remove the stock fuel pump.
 
 

Shows stock 85 in-tank fuel pump bracket compared to 83 fuel pickup tube for external pump.  Bolts right in.
 
 

Fuel lines disconnected.  Cool swaybar huh?  Thats the Addco.

External fuel pump installed. It's a Bosche unit from a Porshe 911 Turbo.
 
 

Another view of the fuel pump installed.
 
 

This is my new and improved turbo oil supply and return line setup.
 
 

Note that welding the big AN fitting warped the flanges slightly so just after this photo was snapped, I took them to my machine shop where they milled the gasket surfaces perfectly flat.
 
 

So as not to get too hot, I replaced the original radiator which was found to have some pinholes starting to develop with a new aftermarket unit.  Note here the tranny cooler mounted.
 
 

I decided I didn't like my gauges up high like with a pillar pod so I stacked two cyberdyne gauge cups together and just hung them from the pillar. These are Autometer Boost/Vacuum and A/F ratio gauges.
 
 

No rice here! Just a relatively inconspicuous badge from the grill of a Japanese mk3 turbo.
 
 

Wheels are 16x8 Compomotive CXN.
 
 

Drivers side view.