Sam's 79 RHD 2+2 SR Swapped

[69sroadster]

Well I finally got the head rebuilt after a little drama.  I also learned a lot in the process about degree'ing cams in the process and that Tomei's lobe centerline spec is in reference backwards from TDC rather than forwards from BDC...HUGE difference.  Basically I put in solid lifters & solid style tomei 260 cam's, supertech dual springs, new stem seals, metal head gasket, mang/bronze guides, and titanium retainers.  When I clearanced the shims, I used the slotted guides on both sides of the rocker arms which required a little bit of machining on the rocker tips.  Clearancing the shims was a royal pain in the butt so I just took a long time and triple checked it.  I also had my timing cover still on and found that the chain slipped at one point before reinstalling the cams...contributing to the pain of degree'ing the cams and resetting timing.  I also did a port match on both sides of the head with my gaskets.  After cleaning up the whole affair and addressing a lot of small issues on the motor, I finally put it all back in the car and fired it up about a week ago.  I haven't driven it yet as I need to finish the transmission first and that's in progress as I write.

 

Bottom line the 350z 6 speed is officially mated to the back of the motor using the adapter plate.  I'm going to have a hybrid driveshaft made using the donor 350z slip yoke and the 280zx rear diff plate.  It measures out to 44" between transmission seal to the diff face for my 2+2 with the way I have to motor mounted in my bay.  It seems like I'm going to need at least a 3" diameter steel tube for the critical speed issues on the driveshaft at high speeds.

FWIW, the stock 350z driveshaft (carbon + steel/aluminum) weighed around 13 pounds and the previous 280zx steel 2.5" dia driveshaft about 38" long (not original due to SR swap) was only 6 pounds.

 

I'm going to make a custom transmission mount to hold up the back end of the 350z transmission and leave room for the exhaust to stay more tucked in.

 

I made my own backup lamp switch "plug" for the 350z transmission using small female blade connectors shaved down.

 

Later on I will get a Cable X box and a Kia Sedona ABS ring gear on the differential input shaft to drive the stock speedometer again.

[69sroadster]

Hi BumbleZ, sorry I didn't see your questions until just recently.  Yes I did most of the wiring myself.  I found some pinouts of the donor car from the manual and had a donor silvia wiring harness.  Using those two together I worked with the existing zx harnesses and relays to get it working.  You should be able to use the zx ECU relays for running the RB ECU.  I also used the ZX AC relay to run the SR compressor, just had to splice in the SR connector on the ZX compressor wire.  Doing this I lost out on the ECU controlling the compressor which would turn the compressor off during full throttle...something I'm not worried about since my hand on the a/c switch can do the same thing.  The RB ECU might not like the ZX fuel pump relays, but I just ran a hot lead from the ECU relays to the ZX fuel pump to energize just one of the ZX fuel pump relays.  It basically runs the fuel pump anytime the ECU is turned on by the ignition switch...so it runs all the time and maybe costs me just a small margin of fuel economy with the constant cycling of fuel through the return system.  Either way it still works well since I can get about 29 mpg on long highway cruises.

[69sroadster]

I also used the ZX temperature wire on the SR sensor.  I tapped the oil pan for the ZX oil temp sensor.  Also used the ZX oil press sensor on the SR oil port near the filter.  I just recently started reworking the tach from what I had before...more to follow on that.  Depending on the transmission your RB has you might just be able to plug the speedometer cable right in to the case.

[69sroadster]

Sorry for any of those trying to follow this at all since it's been a while.  I did finish the transmission mount and reworked the shifter coming through the tunnel area a bit.  I ran into a bit of drama with the transmission though getting it to mate with the pilot bushing and the clutch disk, then it was the throw out bearing assembly.  I just had to swap to the SR20 throw out bearing slip yoke since it is a bit deeper on the front side than the donor 350z one, even though the bearing itself is the same.  I also shimmed out the fork pivot ball with an extra washer to push it closer to the disc.  This helped with moving the whole thing closer to the clutch since the first go it didn't even touch the levers of the PP.  All's well now and the clutch works great so far.  The transmission shifts pretty smooth but I also learned that the 350z 6 speed reverse lock out was out of adjustment.  I was wondering why I couldn't "find" reverse at first.

 

My feedback on the 350 6 speed behind the SR20 for driving is AWESOME!  That transmission gear spacing works like a champ keeping engine speed in the sweet spot.  It was a pain but was well worth it.

 

On the Tomei 260 solid lifter and cam conversion feedback...jury is still out for now.  I need to get a tach adapter finally and wire it in to start running the motor with some feedback over just plain hearing and guessing.  It's a lot quieter than I thought it was going to be though for mechanical noise.  For now I'm still running the stock turbo, MAF, ECU and injectors for the SR20 but it's doing well within a low 11 to high 10 AFR still.  I'd like to find a good dyno in the area for just a quick pull and see what she's doing now.  I did a 8 hour road trip up to Missouri a few weeks ago and it was getting right around 28 MPG still using my GPS.  I attribute most of that in my mind to the slightly shorter 6th gear in the 350z transmission which I want to see what RPM cruising gives me once I get the tach adapter.

[69sroadster]

After a lot of trying to discern between the wheat and the chaff, I finally purchased the Autometer tach adapter and wired it into the coil harness for the SR20DET.  Now the autometer tach works like a champ with no lying at higher rpms.  PM me if you have any specific questions regarding how this works etc.  It wasn't that bad of an install at all. 

 

I'll be getting the Cable X speedometer box converter soon to get the original mechanical speedometer driven again.

 

A/C is all charged up again and working pretty good given the used compressor that came with the SR20 and the original condenser in decent condition.  I am running the Ford Thunderbird electric puller fan through the 3 row aluminum chevy radiator, condenser and 3" intercooler though on low speed only for now and it's doing a pretty good job on the days we've had in Arkansas so far.  A/C blows at about 53 F on recirc mode with 105 F ambient garage temp.  Good enough for me!

[69sroadster]

I'm working through some weird electrical issue now that I've never had before.  I hate those.  I was in the middle of working out the suspension for the Hawaii inspections.  I added the full Techno Toy Tuning adjustable front struts with their bump steer spacers, 250lb springs, and adjustable tension rods.  That took about a whole day to do including replacement of the front bearings, races and seals.  I noticed that my Rota 17x9 rims up front and tires come really close to the strut bottom spring perch.  So far I'm going to limit how low I put the car with this very near interference.  A spacer should take care of that later, but I really try to avoid those.

 

I added some cheap rear spring spacers to lift the rear a little from the Tokico Blue HP set.  My hope is that this will temporarily increase the rear camber to within factory specs and remove a little toe back there, so that I pass their silly rear alignment here and can get registered.  Afterwards I'll take the spacers out and eventually get eccentric adjusters for the toe back there.

 

So far the car rides really well.  There were a lot of fixes in the last two weeks though.  I added a flex section to the exhaust to reduce fatigue on the SS down pipe.  I added a hanger to the exhaust near the transmission mount (custom 350z 6 speed mount).  The front bearings have a very small amount of play/wear but now are new.  I'm pretty happy so far with the TTT stuff and how it feels.  After an alignment I should be better able to state how it handles, but I have to get rid of some stupid short first.  It was running pretty good for having electrical gremlins before I parked it.