'73 240z - Project Build

[demo243]

Wasted a bunch more time today on the rear brakes- but I think I have them sorted out. I’m not stoked on them but hopefully it works out. Bleed and e brake adjust tomorrow and we’ll find out.

 

First I swapped the caliper back to there “proper” (left on left/ right on right sides) as I had set the brake lines up for and jacked up the control arm- short answer was that wasn’t going to work-

 

So I ended up swapping them back to the opposite sides as recommended for the swap (also puts the bleeders up top) and then had some fun with a drill and the angle grinder.

 

 

it puts a pretty sharp bend on the e brake cable but still seems to work- hopefully I can tighten it enough to work.

 

Long story short is I should have just bought the damn Wilwoods… anyway hopefully I get a year or two out of this set up and call it good enough. That’s what I get for trying to cheap out here… 

 

Also definitely gonna have to roll the rears- tried the fender roller I have but the angle wasn’t working and the metal is pretty thick… guess I’m gonna have to go old school and try the phone book technique.

 

till then I dumped the camber plates negative 

 

 

 

Edited April 21 by demo243

[demo243]

And…

 

We are back on the ground!!!!

 

 

Looks so good!!

 

Before we got there though I tried to roll the rear fenders…. With no luck! Broke the fender roller- stripped the nut and all the fender did was cut into the roller… even tried the old book method… but the car isn’t heavy enough!

 

 

Gave up on that - although I may not need to worry about it. Seems like as long as I have the camber dumped it might be ok.

 

Then I added a spacer and adjusted the e brake cable as tight as it would go. Works well enough to torque the lugs… but idk about MA state inspection… ghetto but will do for now.

 

 

Then bleed the brakes- quick bleeders for the win!!! Make life so much easier.

 

Finally while it was in the air I re-made the fuel pump shield with some 1/8” aluminum. It is sandwiched between the pump mount and the body using the Nissan mounts.

 

 

After that I primed the pump and fixed one fuel leak at the front carb.

 

Then I dumped it on the ground! 
 

It went back up for a quick driveway alignment (definitely needs a pro… - tape measure was catching on the oil pan so not really accurate… and likely (definitely) have more front camber then needed).

 

It is LOW! Exhaust flange is 1/2” off the ground!

 

 

Too low I guess… didn’t make out the driveway without scraping…

 

 

Back up it went! Added 1/2” to the coilovers and made it out the driveway.

 

Dumped camber- 

 

Cleaned up and tried to push it back into the garage for the night….

 

Beached!

 

Got it a little further back till the flange hit… then was stuck…

 

 

Really need to tuck this exhaust… lots of room back by the crossmember- it’s a couple inches off of the cutout for the exhaust… but this is the header flange that is the issue… and more frustratingly is I have the same header as a replacement! Hopefully the exhaust shop can help… Thinking some new engine and trans mounts might help a touch to lift the the engine up a touch - need to look into it. 
 

couple of 2x4s should get it in the garage tomorrow hopefully 

 

 

[demo243]

 

Another tape measure alignment and we have a couple more drives in with the car- including a few highway rips. Really happy with the BCs- running 5k/5k springs and it’s firm but supple. Car handles so much better lower and stiffer. Haven’t really thrown it around but don’t think I’ll need a rear sway either. Also seems like the rears clear the fenders. Still want to roll them at some point though to pull some camber out.

 

Definitely have a dirty tank though… two fresh filters….

 

 

 

Also ran into my “stumble” loss of power issue again this morning. This time just cruising around… just all of a sudden loses power, feels like it’s only running on a couple cylinders- Afrs spike super lean. Will stay running if you really force it too with the throttle… stopped it parked, fired it back up and was fine… Not the fuel pump since that was replaced- maybe a clogged line or input from the tank? Would make sense since it clears and goes away? I think it’s fuel since the engine is still running… but I also think it’s carbs because of that ( very similar to my last experience with a starved carb- Weber with stuck needle valve)… hmmm

 

On a cooler note- was digging through some of the stuff that came with the car and found the original window sticker! Lots of other receipts and stuff to go through still.

 

 

Also the kid takes some cool photos sometimes

 

 

[datsunfreak]

17 hours ago, demo243 said:

Definitely have a dirty tank though… two fresh filters….

 

Also ran into my “stumble” loss of power issue again this morning. This time just cruising around… just all of a sudden loses power, feels like it’s only running on a couple cylinders- Afrs spike super lean. Will stay running if you really force it too with the throttle… stopped it parked, fired it back up and was fine… Not the fuel pump since that was replaced- maybe a clogged line or input from the tank? Would make sense since it clears and goes away?

 

This definitely sounds like trash in the fuel system. Especially after looking at that fuel filter... 

[demo243]

21 minutes ago, datsunfreak said:

 

This definitely sounds like trash in the fuel system. Especially after looking at that fuel filter... 

 

The tank will definitely need dealing with. I will probably just order one of the S30world tanks- I’m too deep $$$ wise in this car already so might as well keep going.

 

My only thought is- the fuel filter (at least up front) was still full of fuel. I guess if the blockage was at the pick up then the pump wouldn’t have anything to push so the system would “stall” - but wouldn’t the car die then? The car still runs and will “move” under its own power… just with a severe lack of power… I don’t have a pressure gauge on this system right now and it’s a hard problem to diagnose since it’s so infrequent…

 

 

[Stoffregen Motorsports]

For rolling fenders, we used to use a baseball bat, but any tubing could work. Put the tubing in the gap and move the car forward, backward and the tire will grab the tubing and roll it through the fender opening, and hopefully stretch the fender.

[datsunfreak]

21 hours ago, Stoffregen Motorsports said:

For rolling fenders, we used to use a baseball bat, but any tubing could work. 

 

Wooden bat is important to note, not metal.  😁

[datsunfreak]

On 5/6/2024 at 7:30 AM, demo243 said:

My only thought is- the fuel filter (at least up front) was still full of fuel. 

 

Are you still running the stock feed line? If so, it may also be rusty on the inside? But both of those filters are definitely full of rusty sediment.

 

If your rear filter is horizontal, but the front is vertical, that could also be part of the issue. Horizontal filters are harder to stop up with sediment than vertical ones. But the rusty bits should not have mae it past the first filter to get to the second one, unless the tubing is also rusty.

 

On 5/6/2024 at 7:30 AM, demo243 said:

then the pump wouldn’t have anything to push so the system would “stall” - but wouldn’t the car die then? The car still runs and will “move” under its own power… just with a severe lack of power…

 

Yes, it should stall. Yours would be the first I've seen where "enough" fuel gets through to keep it moving. Usually they stall out, then after they sit for a minute and the sediment falls out of the filter media, it will start back up and drive again.  

[demo243]

12 hours ago, datsunfreak said:

 

Are you still running the stock feed line? If so, it may also be rusty on the inside? But both of those filters are definitely full of rusty sediment.

 

If your rear filter is horizontal, but the front is vertical, that could also be part of the issue. Horizontal filters are harder to stop up with sediment than vertical ones. But the rusty bits should not have mae it past the first filter to get to the second one, unless the tubing is also rusty.

 

 

Yes, it should stall. Yours would be the first I've seen where "enough" fuel gets through to keep it moving. Usually they stall out, then after they sit for a minute and the sediment falls out of the filter media, it will start back up and drive again.  

Still on the stock lines- and yea based on the front filter - the lines are likely a bit rusty too…

 

maybe there is something in one of the carbs that is clogging one of them up.

 

i guess I’ll add fuel lines and a tank to the list for this car… 

[datsunfreak]

10 hours ago, demo243 said:

Still on the stock lines- and yea based on the front filter - the lines are likely a bit rusty too…

 

maybe there is something in one of the carbs that is clogging one of them up.

 

i guess I’ll add fuel lines and a tank to the list for this car… 

 

Usually if I have a rusty line, I don't replace the fuel line, I just keep a few spare filters in the glovebox and and a screwdriver to change them. 😋

 

Now, rusty tank, that's a different story. That problem takes a loooong time to clear up on its own, if it ever does. A rusty fuel line usually will clear itself in a few months and 3-4 fuel filters. 

[demo243]

So it’s happening!

 

 

I had plans to do some other stuff before swapping the carbs but I got motivated today and started tearing stuff apart.

 

Ultimately this was a good thing… I am amazed this car hasn’t burned to the ground!!!! 
 

Started to pull the fuel lines from the fuel rail and barely touched the fuel line under the front carb and it essentially disintegrated in my hands dumping gas on the drive way…. My guess is it was replaced with a non fuel safe hose at some point 

 

 

Anyway here’s a teaser shot!

 

Need to do some grinding/trimming of the manifold and header up front as there is some interference… and need to drop the center section of the exhaust and run it down to the exhaust shop for a O2 bung. Also need to trim or re-bend the heatshield- just catching the header under the manifold. But could potentially have it back together tomorrow. We’ll see…

Edited May 12 by demo243

[demo243]

Slow progress... but getting there!



Biggest issue right now is the throttle cable - its super long in the photo, but was hoping it might work short term- but its too flexy. The cable is the ProTunerz one and it is essentially a waste of money... came with a nice firewall bracket that doesn't fit... along with other issues... going to try and make it work for now. 

Fuel lines are run and attached. Exhaust is all back together. 

Hopefully tomorrow is a test day!

[benzo]

Been following along and reading updates and cool progress! Really curious to see how the HSR carbs work out. 

[demo243]

Lots of teething issues right now as I prepare to fire it. But that’s to be expected with a “new” or under utilized carb set up.

 

Have to rework my throttle cable

set up. Going back to a rod and link but since I already drilled the pedal I need a new attachment rod.

 

Also having a fuel issue- attempted to test the fuel system with the pump on and gas started pouring out of the over flow vents. Could be a few things- 

1)To much fuel pressure- HSRs are sensitive to fuel pressure (2-4 is ideal) and the  Carter pump is 4-7psi- I was hoping with a return I may not need a regulator but that seems maybe not case

2) Bad needle/seat or float adjustment needed - hoping this isn’t the case since they would really need to come off to fix this.

 

Picking up a regulator this afternoon and hopefully get on too and go from there.

 

[demo243]

Grabbed a couple of the wrong fittings yesterday so still waiting on plumbing in the regulator.

 

The bigger issue I am dealing with currently is the throttle cable. Given the heavy return spring on each carb it there is a lot of tension on the cable causing the housing to flex. I re worked the set - going back to a rod off the gas pedal to the pivot and then to the cable- which drastically shortened the cable, but I am still getting so much flex in the housing that I only get about 1/2 throttle at the carb…

 

I have ordered a progressive throttle lever, skillard cable mount, and real Lokar cable. Hoping this will solve the issue…. 

 

Here is the current set up

 

 

[demo243]

Through process of elimination… I have an issue with the rear two carbs.  
 

First installed the regulator, but no change.

 

Then using the super fancy shop towel check it seemed like only the rear one was leaking. So I pulled that line and plugged the rail and tried again. Leaked again, this time showing the second to last carb. Pulled and plugged that one; gave it a shot and we are good- happily holding 2.5 psi (think I need to swap back to the smaller jet in my in line restrictor to raise the pressure up a bit). This leads me to believe there is a float or needle valve issue on the rear two. I couldn’t potentially get to them while on the car but would be hard to make adjustments… biggest downfall of these carbs… so I think the whole rack will come off. Thinking it’s just going to be easiest to pull the whole manifold, hopefully the gasket will be ok. Going to try tonight to atleast get it off

[demo243]

 Verdict is - Floats!

 

Drained em all and pulled the manifold. Lo and behold every single float was below level- ~14-15mm when spec is 18mm… -so I guess I got lucky on the front 4.

 

Pretty disappointing that they were all off from the factory… and dumb on my part for not double checking them when I had them open to install the new jetting…. But anyway got them all adjusted and back on and now it hold perfect at 3 psi on the gauge.

 

 

 

 

 

In other news… this new header while the same? Definitely seems different… pipes feel larger and the collector definitely is- but it sits much higher in the body which gives me some much needed ground clearance…. BUT it is very tight to the manifold… so I suspect heat may become an issue… The header is ceramic coated, but I will need to sort something out with the heat shield… quickly. The carbs are atleast isolated from the manifold with a composite spacer and rubber mount.

 

 

[Crashtd420]

Bit of advise..... move that fuel pressure gauge.... or even plug it once set and leave it off.... I suppose you could even make a small heat shield for it....

 

The heat from the exhaust caused a failure on the one I had in my 521...

I ended up with a small fire from the gas leaking onto the exhaust,  didn't help I used header wrap and it was collecting the gas....

[demo243]

2 minutes ago, Crashtd420 said:

Bit of advise..... move that fuel pressure gauge.... or even plug it once set and leave it off.... I suppose you could even make a small heat shield for it....

 

The heat from the exhaust caused a failure on the one I had in my 521...

I ended up with a small fire from the gas leaking onto the exhaust,  didn't help I used header wrap and it was collecting the gas....

I do have a plug for it- and was thinking about doing that once I get it dialed in.

[demo243]

Waaaahhhhoooooo!!!!!!!  
 

 

Edited May 16 by demo243

[demo243]

Can’t describe how happy I am that it works!

 

Still a number of kinks to work out.

 

- Idle is stuck at about 1200; I believe this is due to the individual adjusters bottoming out on the carb next to them. These truely aren’t needed, but I will need to replace them with a screw to seal the opening. Unfortunately means I need to pull the rack again to get them off

 

- Still having a throttle cable issue, including a very slow return to idle. 
 

- Heat shield is definitely needed as carbs 3/4 are getting hot from their very close proximity to the headed. Might need to re- think the fuel rail mount too to separate it from the manifold.

 

Overall pretty close on the tuning. Carbs are close to sync without even touching it them- 1-4 @ 3.5, 5 @ 3, 6 @ 5. Need to pull the fuel gauge to adjust the 6th carb. Currently at 1 turn out from seated on the pilot and ~14 at a high idle. Quick pull down the street at wide open showed ~14 as well. May need to bump to 145 mains from the 142.5 in there now.

 

Im sure there is more but really just excited it works!

[benzo]

@demo243 Congratulations! That must've been an awesome feeling getting it running. I was stoked to see that video. Makes me look at using HSR carbs for future build or trial.

[demo243]

5 hours ago, benzo said:

@demo243 Congratulations! That must've been an awesome feeling getting it running. I was stoked to see that video. Makes me look at using HSR carbs for future build or trial.

Thanks!!!

 

Really truely happy it worked. And super excited about them. Haven’t tallied the total recently, but definitely less then a set of triple PHH 44s and probably even 40s.

 

Ill try and get a driving video one of these days, although they never seem to come out well.

[demo243]

Snuck a few more minutes in today.

 

My progressive throttle lever showed up so I made a few tweaks to the the cable set up and mounted it up- definitely not the final version of the cable set up; but much better. 
 

Also managed to re-bend my heat shield mounts and utilize two of the old holes on the DSI shield to get a quick shield thrown together. Seems to make a difference on the quick test tonight, need to let the car run longer to be sure. Short term will probably just trim the excess mount and run it.

 

 

Threw the filters on too for the test which helped richen it up slightly.

 

 

On quick initial pull this evening it feels stronger then before. No lag or lack of lowend.

 

Super happy overall!

[benzo]

21 hours ago, demo243 said:

Thanks!!!

 

Really truely happy it worked. And super excited about them. Haven’t tallied the total recently, but definitely less then a set of triple PHH 44s and probably even 40s.

 

Ill try and get a driving video one of these days, although they never seem to come out well.

 

@demo243 Curious to see the total but rough estimate on my end agrees that it is or should be less than the cost of triple PHH carbs.  Definitely look forward to seeing a video.