1983.5 4x4 - retirement truck

[620slodat]

1 hour ago, datzenmike said:

 

 

I only have the '84 specs...

I see 4x4 but don't know where Bloomington is. So California or Federal? Putting the state you are in in your profile speaks volumes as to what emissions equipment carburetor/electrical/distributor was installed.

 

I

 

There are four states with a Bloomington in them, but the only Bloomington I'm familiar with is in CA. I looked it up.

 

Don

[Madkaw]

2 hours ago, datzenmike said:

To be much good the skid pan should be robust. It's to prevent/reduce damage to the oil pan and lower parts of the engine from ground strikes on rocks. Most Datsun cars have splash pans but they are removed to do work and seldom put back on.

 

I only have the '84 specs...

I see 4x4 but don't know where Bloomington is. So California or Federal? Putting the state you are in in your profile speaks volumes as to what emissions equipment carburetor/electrical/distributor was installed.

 

I'll go with federal or non California...

 

Vacuum advance degrees @ inches of mercury

0⁰ @ 3.15

4⁰ @ 4.6-5.9

10⁰ @ 9.4

 

Centrifugal advance degrees @ RPM

0⁰ @ 650

7⁰ @ 1,345

9.5⁰ @ 2,100

 

Indiana . 
so total advance is only 16 degrees at 2100rpm?

[Madkaw]

23 hours ago, datzenmike said:

To be much good the skid pan should be robust. It's to prevent/reduce damage to the oil pan and lower parts of the engine from ground strikes on rocks. Most Datsun cars have splash pans but they are removed to do work and seldom put back on.

 

I only have the '84 specs...

I see 4x4 but don't know where Bloomington is. So California or Federal? Putting the state you are in in your profile speaks volumes as to what emissions equipment carburetor/electrical/distributor was installed.

 

I'll go with federal or non California...

 

Vacuum advance degrees @ inches of mercury

0⁰ @ 3.15

4⁰ @ 4.6-5.9

10⁰ @ 9.4

 

Centrifugal advance degrees @ RPM

0⁰ @ 650

7⁰ @ 1,345

9.5⁰ @ 2,100

 

The 9.5 is probably not crank degrees . I’m assuming 19 at the crank .

So idle 3  + 19 centrifugal is still only 22 - whoo

[datzenmike]

Yes, should have said distributor degrees. I just checked and 9.5 @ 2,100 RPMs.

 

Seems like 22 total is right but 32 would be more like it. 

[Madkaw]

13 minutes ago, datzenmike said:

Yes, should have said distributor degrees. I just checked and 9.5 @ 2,100 RPMs.

 

Seems like 22 total is right but 32 would be more like it. 

But 32 would be more like it ?????

[Madkaw]

So I took a bunch of timing out to compensate for running all 8 plugs now . As per the FSM I’m running 9.5 of centrifugal advance at 2100 - which is actually me punching some keys on my Megasquirt . I dialed in a total of 22 degrees at 2100 . 
I posted up my timing curve on my ECU . As you can see I have a lot more than 22 degrees total after 2200 rpm but as in any centrifugal dizzy advance ,it is a guideline to what is best power without preignition . 
This also help mitigate pinging even with using 87 octane . 
I got to say that the truck is running better than it ever has before . Also pulled a lot of the accel enrichment out too. 
How I knew it was better was a long hill I use for tuning was causing a downshift to maintain speed , but now I just loose a couple of mph. I also read an article that showed best mean torque was at 2800rpm .

That’s about 70mph+ with my 3.89 gears . I also noticed that my tach is off by at least 200rpm.

And I’m running a leaner mixture than previously . Hope to see that manifest itself with mpgs!! 

 

[datzenmike]

Single plug Datsuns like about 32-34 degrees total advance at 2,500 and above. This is with about 10-12 initial plus mechanical but with dual plugs it will be a lot less. Factory says 3 degrees initial for dual plug, a difference of almost 10 degrees between single and dual so your  total advance may be around 22 to 24 degrees on a dual plug engine. Does this sound about right?

 

This is very +- and it will run just about the same slightly over or under and only a dyno will be able to arbitrate if a gain or loss of a few hp. The ass dyno just isn't sensitive enough.

[Madkaw]

Yeah- 3 initial + 19 centrifugal =22 + or - 3 degrees . Then you have vacuum advance at lower KPA . I went a little above that - but not much . The advantage I have is that I can bring in total timing a little later  to avoid any pinging but still be able to run full timing . 
Now that I’ve done tuning on both the single and dual plug arrangement - I’d say the dual is better with the big open chamber of the Z head . 

[datzenmike]

Dual plugs drastically shorten the burn time. This limits the time that oxides of nitrogen can form but at the same time lessens the time for heat to transfer into the combustion chamber walls, valves and piston tops. More efficient if this wasted heat is available to expand the air and push down on the pistons. 

[Madkaw]

On 6/10/2023 at 9:54 AM, datzenmike said:

Dual plugs drastically shorten the burn time. This limits the time that oxides of nitrogen can form but at the same time lessens the time for heat to transfer into the combustion chamber walls, valves and piston tops. More efficient if this wasted heat is available to expand the air and push down on the pistons. 

I agree . I only worked with the 4 plug fire because I was getting a miss running all 8. Turned out to be the injector - weird . 
I’ll stick with the 8 . Just wish the chamber had any kind of quench pad .

 

I can really tell the difference on the highway especially since I got the AC working !!

Very little pinging but you can tell when the AC is on . It loads the motor pretty good but I can still maintain highway speeds-65-70 with out downshifting . I just am realistic as to where the power is on these engines . 

[Madkaw]

Well ugliness of rust has reared its head . 2 winters here where they salt roads and a mouse nest in the drivers rocker made things rot out quickly . I missed this when I was doing all the cab mount work . The rust is extensive and I had to get some rocker pieces cut off and sent out of the -no rust state -of CA . Can’t believe how nice these pieces look ! It’s going to be a pain in the ass to do this because I don’t want to move the cab . This is going to take some surgery because the rot goes all the way thru to the inner rocker panel . 
On a positive note I did get my Pathfinder brakes on the front . Slightly larger rotors and calipers seem to work good . I had a caliper that was hanging up slightly and causing some squealing on the drivers side . Instead of just replacing with stock I read about this “upgrade “ and took a shot at it . Scary part is having to drill out the caliper mount holes on the spindle . You are basically at the point of no return and hope this mod works - lol. 

[bottomwatcher]

Yeah you are going to have to park it for the winter. I am in Maine and brought my 720 up from Florida. I can't go anywhere without compliments on the truck but how all the others rusted away long ago. There are no parts trucks here. Even the hardbodies have returned to the earth long ago. My friend has a junkyard here and if vehicles are driven year round it is about 12 to 14 years from showroom to scrapyard. I can buy running  Ls motors for a $100 a pop but they all look like they came from the bottom of the ocean.

[Madkaw]

Digging deeper . I think I can do this with only having to remove the door . I didn’t want to get in the chain reaction of pulling the fender. I can put a block of something behind the fender with the A pillar bolts removed and should give me room 

[Madkaw]

Off topic of the bodywork - but what should I be looking for in the front end with popping when I initially turn the steering wheel? I don’t hear anything while driving . It’s usually when backing out of the garage or initially turning the steering wheel before taking off . About everything under there is new . I had found the nut loose on the transverse link bushing . When I tightened it I thought I had fixed it - but I guess not . Don’t see anything loose . 

[datzenmike]

Raise the front wheels off the ground and if PS leave engine off. Turn from lock to lock. Should be smooth and no tight spots or binding.

[Madkaw]

1 hour ago, datzenmike said:

Raise the front wheels off the ground and if PS leave engine off. Turn from lock to lock. Should be smooth and no tight spots or binding.

Thanks Mike - I’ll try that and report back 

[Madkaw]

18 hours ago, datzenmike said:

Raise the front wheels off the ground and if PS leave engine off. Turn from lock to lock. Should be smooth and no tight spots or binding.

Smooth as silk !

[Madkaw]

Well I think I’m done cutting out metal . Now I can start thinking about putting it back together . I’m totally bummed how rusty the inside of the rockers are . It’s all manageable but just more work . I’m probably going to just spray it down with KBS rust converter . I’ll make sure I use seam sealer on everything when I’m done putting it together . 
On a good note the engine has been running fantastic and the AC has been doing great .

Funny thing was that I decided to put a subwoofer in the truck . I’m trying to do a clean job with the wiring and  I moved carpet on the passenger side . Underneath was sopping wet and causing surface rust . WTF- what’s leaking ? New door seals , window seals . Then when I moved the carpet more I noticed the drain elbow coming off the evaporator . The AC was dumping all the condensation under the carpet . 
So the subwoofer seemed at first as overkill for the truck but it help me find this leak before it did too much damage . Made the music sound sweeter ! Now I have 4 speakers and a subwoofer so this old man can jam- lol

The subwoofer behind my seat also offers a massage options based on the music you pick !!

I had to take a pic of my hillbilly set up in the back yard . It was so hot I repurposed my old patio umbrella for shade . 

[Madkaw]

Well after trying several times to replace this switch panel - I finally found one and it had the added bonus of the fog light switch . 
I let a friend use my truck and for some reason he broke the original panel that was in the truck when I purchased it .

[datzenmike]

Doesn't look stock.

[Madkaw]

11 minutes ago, datzenmike said:

Doesn't look stock.

Dealer install

[frankendat]

1 hour ago, datzenmike said:

Doesn't look stock.

Did Nissan ever off a stock aux panel?

[datzenmike]

Ahhh for the lamps on the roll bar and such. They were dress up dealer installs.

[frankendat]

I still really like your build. Great work. What kind of mpg have you been seeing?

[Madkaw]

15 hours ago, frankendat said:

I still really like your build. Great work. What kind of mpg have you been seeing?

My driving is almost all city . I drive it like I don’t care about MPG most of the time . I’m lucky to get 20mph - closer to 18 or 19 . 
I honestly thought it would do better . Also I have used AC here and there and I know that hurts the MPG 
What has surprised me is how easily I stay up and ahead of traffic most of the time . I think most of the posts I read about how slow these trucks are is more about those that have to merge to highway speeds in bigger city’s ? I can see that for sure . 
There’s more I want to do to the truck but might have to let it go . My back can’t keep up with these resto projects . This combined with my Z is too many projects for me to wrench on anymore . 
With all the attention I get I know I won’t have any issues selling it