Got it to pass smog, the work begins now... 1986 Nissan 720 project

[datzenmike]

I pulled a shorty from a KC 4x4. Course it was Canadian....

[A guy named Rick]

So from my understanding the 280z transmission is longer right?

[datzenmike]

Even with the Z series front case half swapped on it's 5.5" too long and no way to shorten it. You would have to shorten the drive shaft.

[A guy named Rick]

Is it even worth it? only plus i can see is maybe a shorter throw (it seemed like the throw was shorter on the 280z trans).

[datzenmike]

No. Shorter throw has little value. Shortening reduces the leverage so the shifter is slightly harder to shift.  In the 280zx you are sitting lower so the shifter of necessity, is slightly shorter. On a truck you need to be able to reach it sitting up straight and not leaning forward and fumbling around reaching for it.

[A guy named Rick]

Ok. I'll eventuallly rebuild. hopefully before it blows up.

 

The noise i was hearing, what i thought was a pinging, is in fact engine pinging >.< it doesn't do it when cold. And it's new. It's because i had messed with the float level a little. i had noticed somehow some fuel was getting onto the rubber vacuum caps on this piece in the pic that is screwed into the intake with 2 smaller ports on it:

I thought maybe the float level was too high, so i adjusted. what prompted me to do this? well, one day after work getting into the truck, it idled horrible. i was lucky to get it home. i found out the large cap on that piece was cracked, upon closer inspection it had fuel on it, and same with the smaller one on the lower side.
I'm going to put it back, recheck the idle speed and mixture, also timing. I'm thinking now that i lowered the float level, i'm lean, so the pinging is a lean issue.

[datzenmike]

Looks like the anti backfire valve ABV. It reduces excessive intake vacuum on deceleration and cuts down on oil consumption and popping in the exhaust..

[A guy named Rick]

Yes. I currently don't have it connected and just capped off. No popping in the exhaust. Possibly (most likely definitely) a little oil consumption 

[datzenmike]

The extra high vacuum draws oil up past the rings when decelerating at high RPMs. It's a little thing but it ads up. As this can only happen when you foot is off the gas it has no effect on actual running.

[A guy named Rick]

I just loaded up 1300lbs (mostly dirt) and took it 5 miles down the road to the dump. It did pretty well. Takeoff was a bit shakey if I didn't give it enough gas but I'm not used to that weight. I was 3960 in, 2660 out. It just cruised through town like it was on a Sunday drive. 

Edited October 5, 2021 by A guy named Rick

[datzenmike]

Ride is always smoother with some weight to flex the springs. Did you need to air up the tires? How were the brakes? They can be scary when you're used to stopping in a shorter distance.

[A guy named Rick]

Forgot to air them up >.< I probably was at 35 on a tire with max of 50, but the rims aren't as wide as the tire so they kind of bulge out over a little bit. Also I was about same height as with 800lbs. Not far off the bump stops either. The bed right behind the wheel opening was about 5 inches off the ground, maybe just shy of 5. Afterwards, I was about 9, 9.5 inches.

 

Brakes? What brakes? My booster is bypassed. Hell I don't even know what the pads look like. Yeah, it was a bit scary 😳 

 

 

Edited October 6, 2021 by A guy named Rick

[datzenmike]

Five miles is ok. When the sides bulge the tire flexes all the way round the sidewall and this generates heat. Heat kills tires. Remember that Firestone scandal years ago and the ford explorers flipping or tires  exploding?  That was from under inflated tires.

[A guy named Rick]