James Z31 Engine Blueprinting

[gingofthesouth]

My N15 Pulsar after a fresh oil change would drive from Nelson to Oamaru and still have enough gas to drive around for the weekend while there before needing to be filled back up (45ltr tank). So well over 700km per tank lol

On the other hand my Leopard used to cost $100 in gas (when petrol was $1.30 a ltr) just to get from CHCH to Murchison lol when thrashed.

I think you will be able to do better than 8.9km/ltr. I would expect somewhere around 11km/ltr

[85_Z31]

well the price of fuel is certainly scary at the moment.

had a week driving the Z so I think I will be back in the dirty old Hilux Surf next week !

However i got a heap of real shit little annoying jobs done.

Waster Bottle = connected & working
Drivers side door = adjusted and now sits flush with body work and latches much better
Heater = not stuck on full hot anymore & all the controls now working properly

Rear lights well the previous owner had cut and taped wires together and made a real hack of it so i went to the parts car and pulled about about 2m of harness un clipped it used it to replace all the haggered bits

Result = Rear lights now work and are much much brighter

The reverse lights still don't work because the switch on the gearbox doesn't have any continuity with a a multimeter when i shove it in reverse so at least i know the reason why. It will be an easy fix with a new sensor sent out by my contact in the USA who sends me all the pain in the arse Z parts i need.


and the exciting part is that i am getting bump steer spacers made hopefully next week, I knocked up this drawing a few Minutes ago to aid my mate "Andy" who is going to machine them from 7075 Aluminum tooling plate which is easy to machine and a really high strength.



hopefully those fix my steering wheel shimmy and also the getting pulled left then right sensation that occurs when driving this car

[DylPhil7]

you sir have a skill that would save the rest of use alot of money sometimes haha

[datman310]

good work mate , will have to catch up sometime and have a beer and a yarn

[85_Z31]

What an awesome day today was !

Did some 4th and 5th gear road tuning and sorted out some lean spots which i have been meaning to do for ages

Drove through the lyttleton tunnel a heap of times just simply cos it sounded absolutely tits >

went for a suspension shakedown run from Sumner back to Colombo street, got a feel for the car with the new Koni Rear shocks. Bit much under steer so it took a few goes of adjusting damper settings until we got it "roughed in"

Then i let my mate drive out to his place towards oxford so we could take his dad for a quick blat. During this little tiki tour we found this mint set of off camber rather tight corners that go off tram road onto Swannanoa road so we used this corner as a bench mark for adjusting damper settings.

before adjustment > front end was packing down and felt a bit rough over bumps and this caused a bit of under steer from too much rebound damping

after adjustment > front end felt much more stable and less harsh over bumps in the road under steer was eliminated and the car felt really well balanced with a tendency slightly towards over steer.

for a car that weighs 1500kg and a basic shock + springs setup with OEM tiny tiny swaybars I would call this a huge success for handling.

Initially the car feels sprung quite softly and has a bit more body roll than newer cars, grip is huge balance is good and even with the open single spinner diff traction is really good ( quite surprising )

I think a set of decent Sway bars is the next step to some insane cornering.

and i knocked through about $60 worth of gas in a couple of hours.

bump steer is really obvious I need those bump spacers ASAP

[Bartman]

Time to test it out over the 1/4 mile I reckon. There's a meet this friday.
Don't be saying, "oh, but I need an LSD 1st". Best you try it out as is, and then work on making it better!

[85_Z31]

That would be great and all

but my head nearly touches the roof as is so I Aint going to be fitting in there with a helmet on.

and the steering shake is dodgy as hell over 150 kmh

as a bit of a side note these are the improvements we made in tuning today, notice how the fuel map was pretty rough as guts and now its nice and even.

I think I'm getting near the point where some dyno time is going to be valuable to give things a final check over.

before

after

[85_Z31]

Righto

Drawing for Bump Steer spacers & a bottle of Jim Beam Black was delivered to "Engineer Andy"

Expected to have them back in 7 - 10 days ish

[classicdat]

Hope he uses the drawing before he gets involved with Jim.
Have you checked your 'Toe in' since the suspension changes? Could account for the steering shudder. I have toe in gauge if you want to do a quick check. (could have it done by Friday and go racing!!! Lol)

[85_Z31]

Well one thing I made sure to do was to be there while they did the wheel alignment at the shop.
Caster was in middle of spec for both sides , They set toe in to Nissan specs but camber was quite off
I got to see all the results on the screen as they were doing it too.

I have 3 possible issues with the front suspension

1) Z31's are notorious for bump steer when lowered the slightest amount
2) Mine has had a whack in the front end sometime in its life and LHS camber is -1.5 RHS -0.5
3) I am running nasty old tires that came with the car

I am suspecting the bump steer spacers may not eliminate the steering wheel shudder over 100kmh but you can certainly feel the front of the car grabbing left and right even at lower speeds.

Before the bump steer spacers go in I also want to install the camber plates so i can get both sides at a nice even -1.5 . If this hasn't solved the steering shudder also I will need to look in to getting some new front tires

Then I need to find a Bucket seat & some bases so that i can fit into the dam car with a helmet on !!!