'72 240z RB25DET, no more ITB

[winstonusmc]

Picked up this car in Orange, CA in May. I have been slowly working on it here and there trying to get it roadworthy.

The story:

The previous owner had the car stolen from him and joyridden till the thief had ran it off the road and disabled it. It did some damage to it, but all under the chassis.






There were no carbs on it and the brakes were void of any fluid. I quickly sourced some SU carbs and cleaned and flushed the brakes. I fixed the radiator support and replaced the gas tank as well. The underside was also steam cleaned to get all the sand from underneath.




Now here for the better pictures:








Current mods are:
Full carpet, not sure if the vinyl is under it.
280zx 5-speed

Future Mods:
vented 4x4 fr brakes
rear 240sx calipers

Not sure on the direction I want to go with the engine, but it will have this in it at some point:



Its an Rb25 with a 26 head and ITBs. Running MS3/3X in ITB mode. It was installed in our drift car in Okinawa.

Edited May 29, 2019 by winstonusmc
Update

[kaito]

How much did you pay for the car? I hope it wasnt much.

[winstonusmc]

Well, the dash isnt cracked and I havent seen any rust. So the price was right for the examples I have seen here. It wasnt too much, but it wasnt a $500 "barn" find. It was what I wanted, good enough shape to work with but not too good to not want to modify.

[winstonusmc]

I got the engine running good. The spark plug wires were in the wrong order, which was making it run really rough. The gas tank was pretty rusty, so it clogged the fuel filter a couple times. Now the tank is cleaned up and it drives pretty OK. I think the major kink in the exhaust is hindering my upper RPM power, so a new exhaust is in order in the future. Thinking about the full length motorsport header. I am also going to integrate the MS3 in for ignition only at first on the L24 and run Ford COPs and the 280ZX optical trigger. It handles OK and I wish it had power steering. Cleeaned it up and snapped a couple pics with my daughter.

 

 

[winstonusmc]

Anyone see anything funny with this?

 

 

Now I wonder if its the L24 version of the E88 head, it does have the E88 intake.

[winstonusmc]

Well swapped the rear drums out. It really isnt an upgrade, but it makes it way easier to bleed and adjust. I found a lot of misinformation on what to use with the brackets I went with, so here we go:

 

 

 

88 Maxima flat brackets machined 5mm on the ears and the hub to make a 2mm offset

 

88 Maxima Calipers

 

82 280zx rotors (258mm diameter 47mm depth)

 

brake lines from 240sx calipers (yes others work, but its what I had)

 

random pads that came with the rotors

 

 

 

I think I need more braking in the front, but it seems OK for now. I will go the Toyota 4x4 calipers when I get more time to work on it.

 

 

 

 

 

 

 

 

 

 

 

[Perfect240z]

Looking good!!!

[winstonusmc]

Yeah, for some weird reason, one of the other posts stated that this setup used the 11.4in rotor. No Maxima has a rotor that big, unless I missed something. Not sure what was different about the setup from this post, but I would like to know. I only can think of a different caliper mount.

 

Brake swap thread

[tamo3]

Great progress.

Did you change Brake Master Cylinder too?

[winstonusmc]

not yet, but it doesnt seem to be too bad. I want to go with the Wilwood 1 inch.

[winstonusmc]

Been working a lot the past week to get this thing on the road. Installed a set of S12+8 calipers using the Silvermine spacer. Put a set of Rota RBR 16X8 +4 as well. I think the tires should be a little smaller, 215/45 instead of the 225/50 I got, but its OK. The brakes feel nice and firm now, but I can tell that I need the bigger Master cylinder now. I rebuilt the carbs and they are tuned about 3.5 turns. Installed an MSA 6-1 header and the matching exhaust. Sounds pretty good now. Next up, Megasquirt digital ignition....

 

[winstonusmc]

Swapped the engine out on my 240z a couple weeks ago and have been setting up the MS3 for it. In my previous setup, I ran Spark only in this car to kinda get the bugs worked out, as switching back and forth wasnt too difficult. Once the other engine was in, I added the wiring for the injectors and other required sensors. Now for the specs:

 

F54 Block/P90 head

MS3/3x
Ford Mustang COP running 2.0ms dwell
Nissan 6 channel igniter
82 L28ET distributer running the DIY trigger wheel
Zietronix type MAP sensor (50psi)
420A Chrysler IAT sensor (1/4 NPT)
RB26 TPS (its what I had)
RB26 444cc injectors w/ RB26 resistor
Stock CHTS (temp sensor)
External Walbro 255HP

 

Future Expansion (wired up already):
Idle valve
Boost control
MAF

 

Right now I dont have a wideband, but it should be coming. It idles well, I tuned the fuel to get a smooth idle. I need a better strategy for idle control as the intake I have doesnt have any sort of PWM type valve. I will look into other valves in the future. I will post up the MSQ when it evloves a little more.

 

now for pics:

 

[winstonusmc]

A lot has happened since the last update.

 

After I got the wideband hooked up, I couldnt get it to rev into boost without it leaning out. I traced it to the injector resistor being wired wrong. I fixed it and had another issue, it would randomly cut out and shoot huge fireballs out the tailpipe. I read some things online and turned on the noise filtering on the Megasquirt and got it to not cut out. I guess the wiring is a little more noisey than the Skyline was in Oki. Now the computer is tucked up under the dash where it will be perminently. I also installed an MSD tach adapter to get my tach working. The stock tack is off a little, it will read 6500 at 6000rpm. I had to wire the power to the tach from my internal ECU power or it would keep the car running after the key was turned off, that was a suprise when I took it to the PX, haha. The tune seems to be coming along, the fuel map seems to be working its way out. Its starting to looking like like all the other MS L28ET maps I have seen on the net. One thing I really really need is an intercooler. Blasting down the 15 freeway today at 100mph, boosting 8psi, check out my Air Intake Temps, 213*F, haha. It also doesnt help that the turbo had no intake pipe on it and its sucking in heated air from the exhaust mani. The injectors are at 50% duty at full boost/rpm right now, so I estimate with an intercooler I would be at 200hp at this boost level (8psi)

 

 

[winstonusmc]

http://s253.photobucket.com/user/winstonusmc/media/IMG_20130528_205457_517_zpsd4609492.jpg.html][/url]

 

Using a Thailand source boss kit with a unknown brand wheel. It was purchased in Okinawa and passes the "bend" test

[winstonusmc]

done with the air dam install. The support frame turned out pretty good, but still needs more to keep the bottom of the dam from pushing back at freeway speed. I am just going to put a sheet of ABS from the lip all the way back to the engine crossmember. I might add more further back later too. There seems to be a few posts on Hybrid Z about improving the aerodynamics of these cars, so I am going to do a couple things. Once I mount all the little aero do-dads, I will paint the air dam to match the car. I also shaved the front bumper. I did OK on the welds and need to putty up the welds a little. I hit it up with some flat black for now. I will shave the rear bumper some time this week. It has a few more holes than the front, but its not as messed up as the front was. Now for the pics:

 

 

 

 

Edited August 26, 2013 by winstonusmc

[winstonusmc]

Got the guts to start installing the flares. I am going to cut out the excess like they are supposed to be. Now for some pictures. Check out those rotors, they are 8 months old.

 

 

 

 

[winstonusmc]

Well, the fender flares are done and the fenders have been cut for clearance. I redid the undercoat on the rear fender wells as well. I added 1 inch spacers to get the wheels to fill the fenders. Then when it was all done, I ripped apart the front suspension for a rebuild. New ball joints, bushings, tie rods, and lowering of the strut tubes.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

30mm lower. Just look at that weld! I think I am getting better.

[winstonusmc]

I found a decent set of CRX seats at the auto hobby shop a couple weeks ago. I have been needing a seat with an adjustable head rest so I can install harnesses in the car. With my driving, lap belts are not safe. I have always liked the CRX seat because of its bolstering. These don't have any tears on the seat, just fine tear on one headrest.

Had to fab up a pretty elaborate adapter bracket, but it doesn't sit any higher than the stock seat. Also made it so the seat will slide back further than I can drive, because it can always be slid forward. Only problem is the seat belt gets pinched so it won't pull out while sitting in the seat. Not a problem with harnesses.

 

 

 

 

 

Also put the suspension back together. Went with some Prothane steering bushings and steering shaft spacer thingy. Boy it was difficult to source steering boots, had to go with universal. I am pretty sure how the car sits with the 30mm drop in the front is how I want it.

 

 

[~KnuckleDuster~]

Looking good! Those crx seats look comfortable..can't beat free.

[winstonusmc]

Well they weren't free, but $40 is a good deal.

 

Working on the drivers side seat install today and I noticed two issues. First issue was the seat rails were switched left to right on the stock seats. The difference, other than the "LH" and "RH" stamped on them is that the passenger rail doesn't slide as far back. This is the actual source of my legroom problems, not the stock seats. Second issue was the rear left seat mount on the floor was cracked and smashed in. Not sure why I didn't notice as I was sitting in the seat. I just bent it back up and clamped it in place to weld it. I didn't even catch my interior on fire. Haha. Now the seat almost sits how I want it, just need to add the correct amount of spacers to get the seat angle I want.