1971 240z - Project Crush

[HuD 91gt]

I’ve almost started a thread on here so many times, and it’s unfortunate I haven’t  as the car has been through so many iterations.  But better late then never!

 

The Car.

 

1971 240z 

L28 w/ 0.040 overbore flattop pistons

ARP Hardware throughout

Fully Balanced

P90 Head port and polished by Whitehead Performance

Colt Cams c.542s cam  (.491L 280D)

Kameari adjustable cam gear

OEM Valves

60-2 crank trigger (VR)

LS2 Ignition Coils

Jeep CAS for sequential

240sx Throttle Body

Pallnet fuel rail

440cc Injectors

Ported Intake (hacked open and rewelded)

Ported turbo manifold

HX35w turbo w/12cm housing

Tial MV-R 44mm wastegate

3” DP 

2.5” Exhaust, vibrant super quiet resonator and magnaflow muffler 

2.5” Intercooler piper w/ EBay Intercooler

VW recirculating valve

Bosch 2-wire idle valve

dual catch can setup using OEM PCV

Haltech Platinum Sport 2000 ECU

 

Driveline

 

R200 w/ OBX LSD (Required lots of machine work)

Techno RT diff mount

 

 

Suspension

 

T3 rear control arms

Silvermine aluminum front control arms

Ground Control Coilover sleeves

Tokico Illumina struts

Too much poly

larger sway bars

Konig Rewind 16x7

Continental Extreme somethings 225/50r16

Stock Brakes w/Portafield pads/shoes

Tacoma Booster/Master cylinder

 

Hybridz has been an invaluable learning hub over the years. Just hoping this thread can perhaps sway some traffic to come back over.

 

I’m still playing with wastegate springs, but have seen 10psi with very conservative tuning.  I won’t be increasing over that until I source some larger injectors. 10psi, 80duty cycle and only 5200 RPM (this cam likes to go to 7k).

 

Chickenman gave me a beautiful base tune and has been working his magic, with the help of me fiddling and screwing things up in between.  Once I get proper wastegate springs in, I will be headed to the dyno for some high power tuning.  The car is running like a champ other then some heat soak issues. It’s been many years.

 

Engine wise the car has been through a few versions.

L24 w/e31 head and SUs

L28 w/ N47 head and SUs

L28 w/P90 and SUs

Then introduced MS2 and LS2 ignition coils

Then eventually EFI

Then finally over to the Haltech and added Turbocharger

 

Ill try and keep this thread updated with changes. Next up is most likely strut bar fabrication, and possible reworking of intercooler piping. Possible manifold fabrication.  For now I just want to drive it. It’s been 6 years and now it’s reliable and time to enjoy.

 

 

 

 

 

Edited October 2, 2020 by HuD 91gt

[HuD 91gt]

I just ran down and took a few more shots.

 

Most recently I discovered the 10g WR wire which runs through the car was fried and cracked in many places.   Due to age and definitely helped out by my 140amp CSS alternator.   I ran new wiring where required,  worked out a couple bugs and ran a 4g wire through a 100amp breaker to the starter.  My hope is this take the load off the original 10g wire that runs through the cabin.  I also got a hold of a stock 280z voltmeter and replaced my original ammeter.  Photos attached.

 

Also attached photo of my interior complete with Porsche Boxster seats reupholstered in black leather (they were $200 torn up beige specials). I redid them with a more classic 240z/911 style.  I never ended up adding the heated seats but they are power.      You can also see my ECU/Fuse assembly under the passenger side.

 

Aluminum glovebox.  Holds my AFR gauge when tuning, and switches for manual operation of fans, pumps, antennae etc.

 

also included photo of my fuel system at the rear. The whole assembly comes out with 1 (or is it 2?) bolts. All fixed to a fixture using rubber radiator mounts.  
 

[HuD 91gt]

Photos hide many of the imperfections, but it’s certainly has many many battle scars.   One day a full tear down will happen. But one must have everything setup before they make it all very pretty.

[HuD 91gt]

Since Hybridz is a bit more of an engineering site vs a photo gallery, I made this alignment system after installing the coil overs.

 

string alignment, and I used a cube inclinometer for camber. (iPhone actually works pretty good too).

 

The first time I did a string alignment I used jackstands to mount the string. Everytime You jacked the car up to make an adjustment you had to realign the strings and ensure it was square. With the mounting points of the string attached to the car, you can can make multiple adjustments without worrying.  Was a fun project.

 

 

Edited October 2, 2020 by HuD 91gt

[HuD 91gt]

Decided to build a new exhaust.

Old setup was a 2.5” “Premium Exhaust” from MSA, modified with a vibrant ultra quiet resonator and a magnaflow muffler.

 

Since I’m now turbocharged, 3.0” was in the plans.  I also wanted to add a catalytic converter as I’m tired of smelling like fuel every time I drive the car. So the cat will replace the vibrant resonator.

 

So I spent an hour or two rubbing all pipes and muffler with SOS and WD40, followed by Acetone. Proceeded to spend the next 6 hours today making hanger brackets, and getting the muffler in the exact right spot.  No pictures of that yet, but I do have the pipes!

 

There will be a lot of pie cutting as well to get the perfect fit.  I plan on taking my time on this one but should be done by next week.

 

 

Edited October 15, 2020 by HuD 91gt

[HuD 91gt]

So what I thought was going to take me a couple days took me 5 or 6. Lol. My welding has not improved by not using it it. Amazing. Lol.

 

Here is me using my back purging cap (made of a slice of the muffler outlet which slides over actual pipe nicely, then capped with sheet metal and a fitting threaded in) and welding a few pieces to the old flex pipe. It was 3” as I always planned on upgrading.

 

All welded up and hit with scotchbrite.

The thing that took me the longest, was how to hang the system. I went through many types of hangers and spent the most time doing this. I have the pipe with such tight tolerances to surrounding pieces I needed the whole system to be very secure.

 

I started by hanging the whole system with New car OEM style hangers. They work great but you really need to stretch them horizontally to make your system secure.  By doing this it’s also hard to line everything up exactly where you want.  So the rear muffler hangs off these.

 

This worked for the rear, but wasn’t working with the pipe going through the front differential/control arm mount.  So I used these cheap J hook style ones and made a bracket to the crossmember. Have no clue what those threaded holes were for in the bottom but I guess I’m not going back now. Lol.

 

The thing is rock solid now. So now my welds just need to hold up. As you can see they aren’t that pretty. Lol.

 

working on the tips tomorrow.   They are going to be a little complex. Hopefully it all works out as planned.

 

 

[HuD 91gt]

Tips complete.

 

 

[HuD 91gt]

Always wanted to do a fall shoot with this car. Hadn’t touched my real camera in... years?

 

These turned out well despite missing the sun by about 10 minutes. Damn time change throwing me off. Ha.

 

 

 

[Whitley_280z_2+2]

Those are some great pics! I’m a big fan of the s30 without fender flares and stock body lines plus that’s a great color.

[HuD 91gt]

Thanks! The goal is a bit of a wolf in sheep’s clothing. I’ve got another exciting engineering project on the bench right now. Pumped.

[Whitley_280z_2+2]

3 hours ago, HuD 91gt said:

Thanks! The goal is a bit of a wolf in sheep’s clothing. I’ve got another exciting engineering project on the bench right now. Pumped.

 

Hey that's neat! I'm in the process of trying to find a cheap LSD (kinda impossible) because I think my carrier pin is going bad but I'm not sure I want to take on a lot of machining work like you did with the OBX. Thinking about using an S13 29 spline unit and shimming the bolt holes down to 10mm. 

[grannyknot]

Just found your thread, the car looks beautiful and that engine package much be a blast.  What kind of machining was needed on your OBX?  I have one and only needed to invert gears and replace the cone washers.

[HuD 91gt]

I did the washer upgrade through who ever sells that kit as well.   The issue I had was when checking the backlash.   At one point I had proper backlash, then you rotated ring gear 180 degrees and I had basically zero backlash.   Being the first diff I had ever taken apart I wasn’t sure if I just screwed up but luckily have a machinist friend. He measured it out and the surface which the ring gear mounted to was completely warped. So he tossed it on the lathe. 
 

I reassembled and had even backlash all around. 

[HuD 91gt]

I should state, I’ve never heard of this happening to anyone else before. Put even just the time it took to get a proper working diff, wasn’t worth the few hundred bucks difference.

 

 

If i were to do it again I’d probably go the M-tech route. Or even smarter. The super 8.8 kit that the member here sells. Especially if your going to purchase brakes and CV’s at some point.

Edited November 5, 2020 by HuD 91gt

[HuD 91gt]

In progress... the secret experiment!

 

I needed to pull my manifold to change wastegate springs.   I hate buying new gaskets (cheap ass), and a manifold idea had always been in my head. Sooooo.....

 

True twin scroll manifold using an adaptor from an original 240z manifold.  Cylinder firing order is perfect for an easy adaptor.

I am fearful of the manifold cracking, but the adaptor is designed in a way I can chop off a portion and easily adapt it to a completely new manifold.

 

I didn’t go that route as I can’t get my hands on a flange for a decent price, then this idea popped into my head. The original 240z exhaust manifold actually flows really well. The adaptor is going to use a single 44mm wastegate completely divided right up the the WG valve.

 

Picture time!

 

 

[calZ]

So you're going to run a twin scroll turbo with separate wastegates off a log manifold? 

[HuD 91gt]

No. As the post above explained, I’m using a single wastegate. Stock 240z manifold is divided. My adaptor continues that right to the turbo, and eventually to the valve face of the single 44mm wastegate.

Edited November 12, 2020 by HuD 91gt

[HuD 91gt]

Manifold progress stopped when I had to reorganize the shop to fit in a lathe. Then decided it’s probably just smarter to make a whole new manifold. So I stuck the old one back on and the car is on the road for summer.

 

Hit the dyno for the first time yesterday,  had some ignition issues at 6500rpm so pulled it off the rollers to diagnose.   Got in almost a full baseline run    Funny torque curve.