1983.5 4x4 - retirement truck

[Madkaw]

2 minutes ago, datzenmike said:

The larger 62mm bearing doesn't make it a C transmission. In the FS5W71C the internal bearings and shifter are upgraded, and the gears made wider for added strength. The front case is also different and a 71B case needs clearance machining and drilling besides boring to the larger the counter bearing to fit. Other than the '84 300sx (non turbo) the C was introduced in 86.5 in the, then in production, S12 200sx CA20E and CA18ET with a VG30E the next year '87, and the new replacement for the 720, the D21 Hard body with the Z24i and VG30i.  It was also in the '87 Vanette but useless as it was a remote or column shift 5 speed. The D21 also had a 4 speed 71C from '88 to half way through the '92 model year used on the Z24i and early KA24E engines.

 

There was never an L series 71C so what front do you have on it. Got a picture? It can only be a CA, VG, Z, KA. If not it was swapped.

I matched up the bell housing to a spare Z block - perfect match . So I do have a C trans?

[datzenmike]

That's because a KA and a Z series have the same orientation. OR it's a Z24i transmission from an '86.5-'90 D21 Hardbody or an '87-'90 Pathfinder. (forgot about the WD21 Pathfinder)

[Madkaw]

1 hour ago, datzenmike said:

That's because a KA and a Z series have the same orientation. OR it's a Z24i transmission from an '86.5-'90 D21 Hardbody or an '87-'90 Pathfinder. (forgot about the WD21 Pathfinder)

 

You jogged  my memory -  he said it was an 89 z24i, so it’s a C

[Madkaw]

Well I’m calling it a C

[datzenmike]

It is a C. All Cs have the larger counter bearing but Bs have large and small. A 71B with a larger bearing is still a B. That all.

[Madkaw]

16 minutes ago, datzenmike said:

It is a C. All Cs have the larger counter bearing but Bs have large and small. A 71B with a larger bearing is still a B. That all.

 

So it’s worth installing for sure . Out with the leaky B - in with C/B 

[Madkaw]

On 12/2/2019 at 1:09 PM, Madkaw said:

upload pics in a link

 

Anyone familiar with these shifters . It didn’t come with all its parts I believe . The snap ring should be holding some kind of washer down on top of that plastic bushing in the hole. Presently there is a gap and that snap ring won’t hold the bushing down in place. Don’t have he FSM for this year 

[Madkaw]

 

well after installing this and driving around I realized she needs more fuel!!!!

New Weber seems pig rich at idle and way lean at power 

Ive read a lot about folks complaining of lack of power even with the Weber , but did they tune them . This is a 32/36 . It’s amazing I’m not detonating with AFR’s reading as high as 18. 
At least I’ll know where I’m at before I judge the Napz

Edited December 11, 2019 by Madkaw

[Madkaw]

So my idle mixture is at 2 turns already and the Weber instructions say I need to increase my jet size, but my AFR at idle is at 12 now . The accelerator pump acts like it’s MIA when you step on it - unless you slam it to the floor . Not sure what direction to head to, but going to check for vacuum leaks . Getting great MPG though- lol

[Madkaw]

Vacuum leak found - dam adapter plate ! 

Truck is still leaner than I like . Seems like the accelerator pump needs and bump up and the main jet a size or two. Overall the carb doesn’t do bad. This truck would be a little more fun with some more hp. I believe I can get a bit more at WOT for sure. 

On hard tip in the AFR’s go 17’s - especially above 3K. It goes leaner than that just for a second or two , so the pump jet needs a boost. 

I might get the jet kit and play around . 60 bucks gets me 10 hp or more I’d be happy.

Maybe get he idle much leaner too. 13 is about as good as I can get without compromising the upper end. 

[Madkaw]

Redline jet kit showed up - so time to tune . Let you know the results .

[Stoffregen Motorsports]

On 12/12/2019 at 4:47 PM, Madkaw said:

Vacuum leak found - dam adapter plate ! 

Truck is still leaner than I like . Seems like the accelerator pump needs and bump up and the main jet a size or two. Overall the carb doesn’t do bad. This truck would be a little more fun with some more hp. I believe I can get a bit more at WOT for sure. 

On hard tip in the AFR’s go 17’s - especially above 3K. It goes leaner than that just for a second or two , so the pump jet needs a boost. 

I might get the jet kit and play around . 60 bucks gets me 10 hp or more I’d be happy.

Maybe get he idle much leaner too. 13 is about as good as I can get without compromising the upper end. 

If you're looking for more WOT power, you can remove the choke plate from the secondary side and cut the shaft out (or leave the shaft). Another trick is to remove the brass tube that is inside the auxiliary venturi (secondary side only). Pegasus racing sells different aux venturis that are special for Formula Ford racers that are slightly different and they also help with power.

 

Every little bit helps!

 

EDIT - I just checked their website and I don't see the optional aux venturi anymore. I bet Pierce sells them.

Edited December 20, 2019 by Stoffregen Motorsports

[Madkaw]

1 hour ago, Stoffregen Motorsports said:

If you're looking for more WOT power, you can remove the choke plate from the secondary side and cut the shaft out (or leave the shaft). Another trick is to remove the brass tube that is inside the auxiliary venturi (secondary side only). Pegasus racing sells different aux venturis that are special for Formula Ford racers that are slightly different and they also help with power.

 

Every little bit helps!

 

EDIT - I just checked their website and I don't see the optional aux venturi anymore. I bet Pierce sells them.

Why not try re-jetting the carb ? Not just looking for WOT improvement, looking for better response and midrange too. Just to hold me over until I go EFI anyway.

[datzenmike]

What is this weber for? Is it for a Z24?? Is it rebuilt? Is it unknown?

[Madkaw]

3 minutes ago, datzenmike said:

What is this weber for? Is it for a Z24?? Is it rebuilt? Is it unknown?

New 32/36 DGVE on my 720 

[datzenmike]

So it a direct replacement for the 720's Z24? If yes it should be jetted close enough. You're assuming the gauge is correct. Did you calibrate it? The one I have needs to be run through a start procedure with the O₂ sensor out of the exhaust pipe.

[Madkaw]

Brand new 4.9 Bosch - doesn’t need to be calibrated - so they say . I believe it’s accurate and I think the carb is jetted to lean - but for most fine . The truck would be much more fun to drive if it responded better . Seems the accel pump could use a bigger squirt and the main air jet could go down a size . 
I believe it’s lean to the point you could risk detonation . 

[datzenmike]

The gauge, not the O₂ sensor. My O₂ as to be run in an oxygen atmosphere to 'calibrate' it, then installed in the exhaust pipe. It says to do this every 6 months just to be sure it hasn't wandered. Have a look through your installation instructions. Also is the O₂ sensor at least a foot after the collector and is it mounted above the center line of the exhaust pipe? Any chance of a exhaust gasket leak?   

 

This is a new 32/36 for a Z24 so why would it be jetted so lean?

[Madkaw]

Spartan Wideband . I’ve been running Widebands for years in other cars . I do need to recheck my manifold collector gasket . Nissan is the only good ones .
 

[Stoffregen Motorsports]

On 12/20/2019 at 1:45 PM, Madkaw said:

Why not try re-jetting the carb ? Not just looking for WOT improvement, looking for better response and midrange too. Just to hold me over until I go EFI anyway.

You did say you were looking for more at WOT.

 

Proper jetting is a great idea!!!

[Madkaw]

Played with Weber tuning today . Didn’t take long to run out of jet sizes . I didn’t touch the idle circuit , but put larger pump jet and increased jet sizes to 155/150 on the mains . Gauging by my Wideband , I’m still lean at WOT above 3k rpm. At only 14:1 the AFR’s are tad lean on a hard pull. I was able to lean my idle to around 15 :1 , versus 13:1 earlier . Cruise is nice and lean too. I also added in some timing to about 10 BTDC initial . Truck is much more responsive now and faster on hard acceleration . I’ll see how well the engine does with this much timing . Idle is sitting at about 750-800 rpm’s with no dieseling so far .

 

 

[datzenmike]

 

Check your advance above 3k with the vacuum advance hose off.  Subtract the 10^o you set and this should be your mechanical advance. My FSM says it should be about 20^o is it?  The last thing you want is the total (initial  + mechanical) being over about 33-34 degrees.

[Madkaw]

9 hours ago, datzenmike said:

 

Check your advance above 3k with the vacuum advance hose off.  Subtract the 10^o you set and this should be your mechanical advance. My FSM says it should be about 20^o is it?  The last thing you want is the total (initial  + mechanical) being over about 33-34 degrees.

Well if my timing light is accurate then I should be right there around 32. I think I have 12 initial now. Heard some faint pinging on a hard pull uphill in 5th gear, which I wouldn’t do normally . I do have the white wire disconnected to the dizzy. 

[datzenmike]

Sounds good.

 

Are you running all 8 plugs? Stock 8 plug is 3^o the thing is that dual plugs lessen the advance needed. 10-12^o is more like a single plug advance.

[Madkaw]

4 hours ago, datzenmike said:

Sounds good.

 

Are you running all 8 plugs? Stock 8 plug is 3^o the thing is that dual plugs lessen the advance needed. 10-12^o is more like a single plug advance.

Yes - running all 8 . It ran good with 5 BTDC - I’m just playing around . With a performance carburetor I thought I could try for more timing to improve performance . I’ll run it a while like this and check my plugs and listen for pinging . 
How much vacuum advance do these dizzies have ?