Utah Hawkeye Posted July 22, 2011 Share Posted July 22, 2011 I just finished replacing the blown turbo on my 280ZX with a turbo off of an '86 Z31. I searched several forums for info to help with this swap and found only limited info. So I decided to post up on this and hopefully some one will benefit. The first thing I realized was the difference in the exhaust side where the waste gate is located. Z31 turbo L28 turbo You can take the wastegate/ downpipe outlet off the L28 turbo and put it on the Z31. But, the studs will have to be swapped in to replace where bolts were used on the Z31. Just make sure they're long enough to reach through and have enough room to bolt on the downpipe. This is what it looks like with the new studs and bolted together. As you can see I initially tried to use the wastegate actuator of the L28 turbo. This became a problem I'll get into later. In order for the turbo outlet to clear the intake manifold, the turbo side needs to rotated away from the engine. This is easy to do. Just loosen all the bolts that hold the turbo housing to the center section and slide it. I had to modify (grind down) the oil outlet on the bottom in order for it to clear the new bolt postition. This pic shows the stock position of both turbos. Also, on this note, I ended up using the oil outlet that was on the Z31 turbo and a longer piece of hose to connect to the oil sump. The 280zx tail was in direct line with the steering shaft. The only other problem I had was getting the waste actuator right. I initially tried using the 280zx actuator 'cuz it fit better after changing the position of the turbo housing. But, I wasn't getting the needed response. This may be due to the fact they are set up for different amounts of pressure to move them. Anyway I ended up lenghtening the actuator rod on the Z31 actuator by cutting the threaded area in half and threading a piece of steel tubing to lengthen the rod. That did the trick. The rest was a matter of plumbing in the coolant lines. I taped into the thermastat housing and teed off of the inlet on the other side. The I used the tubing from the Z31 plenum to go around the rear of the engine just to give it some stability. It's a pretty simple, straight forward swap and you get the added benefit of water cooling. Quote Link to comment Share on other sites More sharing options...
Pyro Posted August 18, 2011 Share Posted August 18, 2011 To fit a first gen 300 turbo in the exact same position, the exhaust turbine also needs to be reclocked. Looks about 15 degree difference between the 280zx and 300zx turbines. But, not so easy to reclock the exhaust housing, as these tend to "rust lock" on the center section. Quote Link to comment Share on other sites More sharing options...
Utah Hawkeye Posted August 19, 2011 Author Share Posted August 19, 2011 To fit a first gen 300 turbo in the exact same position, the exhaust turbine also needs to be reclocked. Looks about 15 degree difference between the 280zx and 300zx turbines. But, not so easy to reclock the exhaust housing, as these tend to "rust lock" on the center section. I did address this issue. (see fourth picture) As far as the "rust", niether of the Z31 turbos had any rust issues when it came to changing the relationship of the two halves. Quote Link to comment Share on other sites More sharing options...
Pyro Posted August 19, 2011 Share Posted August 19, 2011 I'm talking about rotating the exhaust turbine in relation to the center section. Not rotating the compressor in relation to the turbine. The compressor side rotates easily, so not over concerned about that. The 4th picture shows the different positions of the exhaust turbine as compared to the center section. In order to get the oil input port in a straight-up position, the exhaust turbine needs to be rotated (not the compressor). Quote Link to comment Share on other sites More sharing options...
xShodaimex Posted September 23, 2011 Share Posted September 23, 2011 great job! does it run the same at the turbo from the 280zxt? Quote Link to comment Share on other sites More sharing options...
billseph Posted November 17, 2011 Share Posted November 17, 2011 I'm going to be doing this pretty soon since I bought a Sport 400 (From JWT) that was previously on a '84 300zx. Can anyone with turbo knowledge tell me if there are any gaskets or seals that need to be replaced or taken special care of when clocking the compressor or exhaust turbine as Pyro had mentioned. This will obviously be my first time doing this. I have average mechanical skills (not a dummy). Is this one of those things I should leave for someone skilled though so I don't screw up my nice turbo in the process?? Quote Link to comment Share on other sites More sharing options...
aplyedmind Posted November 17, 2011 Share Posted November 17, 2011 I'm going to be doing this pretty soon since I bought a Sport 400 (From JWT) that was previously on a '84 300zx. Can anyone with turbo knowledge tell me if there are any gaskets or seals that need to be replaced or taken special care of when clocking the compressor or exhaust turbine as Pyro had mentioned. This will obviously be my first time doing this. I have average mechanical skills (not a dummy). Is this one of those things I should leave for someone skilled though so I don't screw up my nice turbo in the process?? Got any pics or specs of the 400 sport (From JWT). Quote Link to comment Share on other sites More sharing options...
billseph Posted November 17, 2011 Share Posted November 17, 2011 Specs are: "The T3 turbine housing is a .63 A/R ratio and the T04E compressor housing is a .50 A/R ratio." -JWT I have to wait till I'm home tonight to post up pics. Quote Link to comment Share on other sites More sharing options...
LanceVance Posted November 17, 2011 Share Posted November 17, 2011 Out of curiosity, what size tap did you use for the thermostat housing? I'm going to be doing something similar here in the future, but I don't have the housing handy to measure... Quote Link to comment Share on other sites More sharing options...
billseph Posted November 17, 2011 Share Posted November 17, 2011 Don't know if you'll get a response...looks like Utah Hawkeye (OP) just posted this how-to up then stopped posting. Quote Link to comment Share on other sites More sharing options...
Utah Hawkeye Posted November 18, 2011 Author Share Posted November 18, 2011 great job! does it run the same at the turbo from the 280zxt? It is boosting a lot higher. Using the same setting on the MBC I was getting about 6 lbs compared to 10 lbs with the new turbo. My compression is only about 120 so it's been awesome. Quote Link to comment Share on other sites More sharing options...
Utah Hawkeye Posted November 18, 2011 Author Share Posted November 18, 2011 Out of curiosity, what size tap did you use for the thermostat housing? I'm going to be doing something similar here in the future, but I don't have the housing handy to measure... The therm housing has a 3/8" pipe thread that wasn't attached to anything. you can see it in the 7th pic. Quote Link to comment Share on other sites More sharing options...
billseph Posted November 18, 2011 Share Posted November 18, 2011 Hey Hawkeye you're still here. So is clocking the compressor just as easy as loosening the bolts and rotating it, no seals, gaskets, any anything to be extra careful with to avoid tearing anything up?? Quote Link to comment Share on other sites More sharing options...
Utah Hawkeye Posted November 18, 2011 Author Share Posted November 18, 2011 (edited) Hey Hawkeye you're still here. So is clocking the compressor just as easy as loosening the bolts and rotating it, no seals, gaskets, any anything to be extra careful with to avoid tearing anything up?? Yes, that's right.Depending on the the condition of your turbo (rust etc) It should just slide to where you want it and then just tighten it back up. I should add that all the seals and gaskets on exhaust/high heat areas will nearly always be made of metal. So they're pretty hard to bugger up. Edited November 18, 2011 by Utah Hawkeye Quote Link to comment Share on other sites More sharing options...
billseph Posted November 18, 2011 Share Posted November 18, 2011 Yes, that's right.Depending on the the condition of your turbo (rust etc) It should just slide to where you want it and then just tighten it back up. I should add that all the seals and gaskets on exhaust/high heat areas will nearly always be made of metal. So they're pretty hard to bugger up. Thanks for the info...I figured metal sealing to metal would be the case due to the super high heat. One other question. The oil intake port on the turbo that Pyro had mentioned should be facing straight up...is this a necessary step?? Is this just being suggested so that the routing for the oil lines stays the same or is it a necessity to have it facing straight up for proper lubrication?? I think you'd said you used a longer hose for the oil outlet from the turbo to the oil pan, right? Thanks again, this thread has been very useful for a newbie like me. Quote Link to comment Share on other sites More sharing options...
billseph Posted November 19, 2011 Share Posted November 19, 2011 (edited) OOPS> Edited November 19, 2011 by billseph Quote Link to comment Share on other sites More sharing options...
billseph Posted November 19, 2011 Share Posted November 19, 2011 Here's a photo of that Sport 400 you were asking about Mark. Ben at JWT said a customer had brought this in when he upgraded to one of their newer turbos. Quote Link to comment Share on other sites More sharing options...
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