roger.svoboda

Not a hundred percent sure on this but I've been told by some very reliable folks that the pistons in n/a engines are flat top and they dished the pistons on the turbos to reduce compression ratio to take the turbo boost. The block and head are the same dimension. Even tho there are differences in the p90 and p72 heads the combustion chamber is supposed to have the same volume just depends on the pistons installed in the engine.

If you are talking about just getting it running then you need to do this. There is a piece o metal with teeth marked in degrees 0 to 30 to the left of the crank pully looking at the engine. You should be able to move the engine around until you see a notch in the pully that matches to the 0 degree mark. Pull the rocker cover. If the two cams for #1 cylinder are pointing out and up one to each side of the car you are at the top of the power stroke. If one of the cams is down you are at the beginning of the intake stroke. Move the engine 360 degrees and you are now at TDC for the power stroke. Pull the dizzy cap you should see line on the cap with a number 1 stamped there. this is the #1 spark plug wire hole. Your rotor should be pointing at this spot. You will note that there are six indents in the distributor where the cap mounts and they correspond to the six cylindrs. If the rotor is not pointing to #1 plug wire you need to drop the oil pump. need to drop the sway bar first so you can drop the oil pump. I cut a 6" M8 bolt head off to use as a guide pin otherwise you be cussing all night. The guide pin wil keep the oil pump under control while you move the gear and rally makes it easy to get back up where it belongs. Get a picture in your head of where the rotor needs to go to point to #1. Drop the oil pump until you see the gear. Turn the gear to where you think it needs to go. Put in one bolt to hold it go back up and check the rotor position. continue until rotor is in correct position. Check firing order when you put the plug wires on. As said above to get timing on correct you need a timing light. Schucks and probably other auto parts stores will generally rent you one.

NA tranny pull out is even easier since exhaust easier to get out of the way. If you haunt the junk yards a NA five speed pretty easy to find. More power get a turbo. If you can find a five speed in a 2+2 at the junk place take the flywheel and clutch. The 2+2 clutch face is larger than coupe and you get a bigger clutch for free.

Not a big job I replaced an auto tranny in my 81 turbo with a five speed out of a junker. Take maybe a 6-8 hour day first time around unless you are a very good mechanic. What the trick is to some extent depends on if you can get a Borg T-5 tranny to replace or take to a tranny place and rebuild. Guy quoted me around $400 if I brought the unit intothe shop. You definitely need a tranny jack (or a helper with arms the size of my leg). Harbor Freight has a good one for under a hundred. You need to clear the exhaust piping out of the way plus some tin under the rig. The exhaust piping has a ground metal joint where the elbow comes out of the turbo held by three bolts. I took this off the 81 and an 83 and the joint was rusted solid. I had to remove from the turbo itself. This can be done but mighty tight in there. Take off the tin (heat shields) in the engine bay to get at the nuts. You can get at the bell housing nuts from underneath with about a three foot extensioin and an air ratchet (I think I used two 12" and a 6"). Demount starter and clutch slave. Probably need gaskets for the cat converter. While you are in there you might as well put in a new rear engine seal and clutch. Whether you machine the flywheel is a toss up unless it is really bad.

Well the 81 only came in automagic tranny. Got a beefier driveshaft and a R200 rear end and cv joint rear axles. 82, 83 came with Borg Warner T-5 tranny R200 rear end and cv joint rear axles bigger clutch. Clutch is the same diameter as the 2+2

I've got a 2+2 flywheel which is 240 mm across the friction area and it says E30 so maybe that doesn't mean a thing. Have you checked local junk yards there are tons of 280 around.

I'd look around for a 280 turbo and do a swap. I bought a 81 for $450 and an 83 for $300. Just need to keep looking. Presently waiting for breathing room to put the 81 engine in an 83 N/A that is in really fine shape.

Sounds like you blew off one of the vacuum hoses someplace. Buddy of mine did that on the dyno with a 300zx

No As I pointed out when I turn the temp control all the way high this de-energizes the clutch which drives the compressor thus it is just freewheeling - even if the compressor were completely frozen if the clutch is not energized nothing happens as far as what the engine senses. I also find it hard to believe that a 5 HP compressor which is belt driven could affect a 180 HP motor to the extent of what I am seeing. At some point the belt would just wear through.

Got a 81 turbo zx that I put a 5 speed into. Runs great EXCEPT after about 8-10 miles running with the A/C on the engine starts surging. Either losing spark or fuel too lean/rich? When it starts surging you can put the thermostat to high which should disconnect the compressor and electrical but has no effect on the surging problem. As soon as you move from A/C to another climate positiion the surging ceases and car once again performs well. Checked all the vacuum lines I could find and seems okay. Car only has 138k on it and runs strong (when A/C not on). Got boost up to about 5psi. Happens in any one of the A/c selections. This is a manual (not the fancy one) climate control. Any one got an idea??

Had the same problem on my 300zx and the 280. Heard the hoorah about grease in the cup. Both clean as a whistle. Put the battery powered drill direct to input of the console both speedos worked just fine no jump smooth accel and decel. Took out the cables wiped dry lubed made sure there were no kinks and both units now work just fine. I think the 280 was pulled out after some one ran over a parking thingy and was just touching the drive end enough to make the thing move. Not sure about the 300 but both times I believe it was cable problem cause bench test of the meter was good. I'd take the cable out of the tranny and stick a drill on it (ccw). Have someone watch the meter. Make sure no kinks. Don't forget the 280 has that short stub under the dash. Be sure everything is mated up. good luck.

When you say swap the pinion flanges which is what I have been told before it will not work as the turbo drive shaft inputs to the R200 differential with a flange that has a wider bolt pattern and larger spline than the manual tranny which inputs to a smaller flange and bolts to a R180. Unless what you mean is diassemble the R180 pull the pinion and flange out and the replace the pinion and flange that is presently in the R200 which is mounted in the car at present. Is that possible moving pinion shaft from one diff to the other.

yeah that was kind of what I was leaning to. Need to find a place around here that can do that. I a missing a lathe and a MIG machine to do it myself. Thanks for the reply

I looked at a lot of threads that danced around this but my lack of experience doesn't let me interpret some of what I read. I've got an 81 turbo with auto tranny. Got a 5-speed out of an NA at the junkyard took all the parts I thought I needed. When got to the final drive shaft install I found out that there are two versions of driveline for these cars. There was a thread I found where someone called it the big bolt vs small bolt drive shaft. said they were both R200 but one has 8mm bolts with D head and tother be 10 mm hex. Input flange on the turbo is larger bore than drive shaft I have so bolt pattern wrong. I can get a differential out of an 83 2+2 NA which seems to have the cv joint axles that i have. Anyone know if this would be a direct swap. Sure hate to go back to that automagic tranny.