my_mad_z

Hi Will, I agree with you! It would be much easier and cheaper. Unfortunately we don't have that option in Australia as the 280ZX didn't have the option of turbo here. Matt, if you can, and you are willing, do the swap with the 280ZX turbo.

Matt, I turbo charged my L28 in a 260Z 2+2 a few years back (R.I.P. 260Z!) The setup included the following: F54 block. P90 head. 240Z cam. Flat top pistons (standard). Chrome Molly rings. Standard rods. Standard bearings. T03/T04 hybrid turbo. Twin 1.75" CD Zenith stromburg carbs. 42mm wastegate. Water/methanol injector that work of a pressure switch in the manifold. 3" mandrel bent exhaust. Running between 17-19psi boost. Electronic ignition. Holley blue fuel pump. The setup worked very well, plenty of power but not as reliable or efficient as a fuel injected turbo which is what I'm working on at the moment. Let me know if you want more info on the setup. Marc.

I was told by a mechanic that a block should be honed from both openings, i.e. from the top of the block and then the bottom of the block. Do all cylinders from the top and then turn the block over and repeat. I was also told to use kerosene and plenty of it while honing. As mentioned in previous posts, keep the up/down motion consistent and quick in order to achieve a good hatch. I've used this method and achieved a very good hatch and have had no problems with rings bedding. My 2c. All the best with the rebuild.

SuperDave, I recently changed the rear wheel bearings in my Z and it was a real pain removing the stub axle. The way I managed to get it off was to put the retaining nut back on the stub axle (screwed on so that the top of the nut is flush with the top of the stub axle thread); I then put a socket over the nut and hit the socket with a hammer. It took a fair few blows to get the stub axle loose but it didn't damage any of the components. If you have access to a press, that would make life easy. Hope you manage to get them out! Marc.

Aussie260z, sorry, haven't had a chance to take photos yet, will post them asap. As for the setup you are considering, anything is possible; all depends how far you want to go, how much money you want to spend, and if you're doing the job yourself or getting someone else to set it up. The reason I used the peugot discs is because they were very close to the 240z/260z specs. All I had to do was increase the centre diameter from 76mm to 81mm and then offset the stud holes (took about 15min) I used the 260z hubs with the rotors due to the different thickness of the new rotors. The calipers were a straight bolt on with slight modification to the brake line. From memory, the offset remained the same or may have changed slightly, but very minimal from memory. I can understand and appreciate the AU111/falcon discs as you will have greater braking force, but as I said, it all comes down to your budget and how far you are willing to go.... I've seen a convertible 240Z that upgraded the front brakes to falcon brakes (not sure what year though) and he actually used the 5 stud pattern. I'm not sure what was involved in the conversion, didn't get to ask the guy, but it is possible. I'll post the pics asap. Marc.

Aussie260z, I'm not sure about the maxima rear caliper bracket, haven't seen one. All I did was used the original skyline/pintara bracket and made it fit. From memory, I think I had to increase the diameter and drill a couple of holes, was a very simple procedure. The handbrake can be attached directly to the caliper, with very minor filing of the handbrake bracket. I did this initially but found that the cables were a touch too short and would rub on the drive shafts. I have resolved this issue by extending the cables and the handbrake works fine. In regards to the master cylinder, I tried to get a new 280zx master cylinder but found out that they dont sell them brand new anymore in Aus. So I spoke to a few brake specialists and they said it would be fine to use a 260z master.....one guy suggested I remove the one-way valve for the rear brakes (located in the master cylinder) to compensate for the disc upgrade. I haven't done so yet and the pedal feels fine. I'll take some photos of the upgrade and post them up as soon as I can. Cheers. Marc.

Aussie260z, I've upgraded to the 4 spot toyota calipers with peugot vented and slotted discs on the front and I've used the skyline/pintara discs and calipers on the rear..... as far as I am aware, the brake tests are done from 60-0kph and 100-0kph; they measure the braking abilty over these ranges. However, with more power, you would want the extra braking force for safety. I am also heading towards a turbo setup, however I'm sticking with the L28. I had a turbo L28 in my 260Z but didn't do any brake upgrades..... ended up T-boning a van that made an illegal u-turn in front of me, I was doing 60kph and couldn't pull up - brakes locked up; caused $16,000 damage to my Z; so as u can imagine, I'm going for bigger brakes this time! The standard brakes were ok for normal driving, but trying to pull up suddenly or from high speeds was a challenge! I spoke to an engineer in Melbourne and he was quite happy with the brake upgrade I mentioned.....I'm an engineer myself, and I'm confident with the setup. I'm aiming for 200kw+ at the rear wheels and I'm sure that the brakes will be fine. A friend of mine has a 383 chev(stroker) in his 240z (approx 250kw rwhp) and he's using the same brakes on the rear but different on the front (from memory, I think they're toyota corona brakes that are smaller than the peugot/4spot caliper setup I have). His brakes work quite well, pull the car up very nicely, however after a copule of hard braking sessions, he gets brake fade. I believe that with the peugot/4spot setup, the braking force will be sufficient for 190kw. The setup was fairly cheap too.... $200 for the 4spot calipers, $136ea for the peugot vented/slotted discs(brand new from dba), and $100 dollars for the skyline/pintara discs and calipers (pick a part) - all up, $572. I had to do some machining on the front discs, bracket fabrication for the rear calipers and that was all. I realise that the 4spot toyota calipers are heavier than alloy calipers, however I have no intentions on circuit racing. Apologies for the long reply. Marc.

I had the same problem with my 260z. I ended up getting an on-car wheel balance and I never had a vibration problem again. This was the wrong way of fixing the problem, but as mentioned in a previous post, it could be a number of things that are worn that are contributing to the vibration. The problem with getting an on-car wheel balance is that once you remove the wheel, it must go on exactly the same way it came off, otherwise the balance is thrown off. It's a cheap alternative to rectify the problem but not the best way! I've made sure that this time I won't have vibration problems in the 240z; i've replaced all rubbers and bushes and also changed the wheel bearings. Hope you solve the problem. Marc.

Just wondering if anyone knows where I can find volumetric efficiency figures for the L28? I tried searching on the net and found the figure 70%, but I'm not sure how accurate this value is. I also searched the forums but found no specific specs. Does anyone know where I can get the figures from? Thanks in advance. Marc.

I had the same problem when I lowered my 260Z.... the car use to get airborne over small bumps at high speeds....very scary! I had king springs and standard shocks, mind you the shocks would bottom out all the time, had to replace them every six months. I got a quote to install a decent suspension setup, $2,500-$3,000.... I decided to stick with the setup I had. I have overcome the problem with the 240z I am restoring at the moment. I took matters into my own hands and decided to modify the suspension. I removed the struts and started cutting; I cut approximately 55mm from the front struts and 60mm from the rear (can't remember exactly). I then welded the threaded sleeve back in place and reinforced it. The shockers that I have used for the front are actually out of a toyota camry, and they work fantastic! I had to relocate the spring saddle to ensure that there would be a sufficient preload. I used the original 240z front shockers for the rear. The car sits at a very nice ride height and doesn't bottom out. My next step is to install coilovers, but I haven't been able to source them at a reasonable price yet. So until then, I have actually used a cominbation of 240z and 260z stock springs; the king springs were no longer suitable for the application. A friend of mine has a very similar setup on his Z and I can tell you that the car handles and drives like a dream. Speed technology in Mitcham do a full suspension setup, making everything adjustable, however it comes at a price.

If you have the Haynes manual, it has a description on how to dismantle and check the altenator. I can't remember off the top of my head but to access the brushes, there is a black plastic cover that you have to remove located at the rear of the alternator. Once removed, you will see the state of the brushes.... there is a minimum length that is required for the alternator to function correctly, I'm not at home so I can't check the specs. Good luck!

Not sure if you read my post or not, but if you're saying you've replace everything electrical and you're still experiencing weak spark, I'd be checking the altenator.... If the brushes are worn or the voltage reg isn't operating correctly, you're going to get a very weak spark, as a result the motor will missfire, and the plugs will foul because the spark is not detonating the mixture sufficiently. The altenator affects both electronic and points distributers, so I would recommend you check the altenator. Another thing to check is the condensor/capacitor that is located on the dizzy. I've also experienced problems with this which causes similar problems. I know that the points dizzy has a condensor but if you're using electronic ignition, there is no condensor. Start at the condensor first as it's easier to access; if there is no change, check the alternator. Even if the voltage output from the alternator is within specification, I would still check the brushes; the reason is that the alternator may work fine with no load, but if loaded, the output may not be enough. Hope you get to the bottom of this problem. Seasons Greetings. Marc.

Could it be possible that you're not getting adequate spark to ignite the fuel? I had a similar problem with my Z, would back fire and carry on when I ran the motor (backfire through the carbs, miss, and rev poorly)..... I disconnected the battery while the car was running and the revs picked up and it ran smooth. Turns out my altenator was stuffed and there wasn't enough voltage going to the coil. I'm not sure if you have points or electronic dizzy, but a low voltage supply can affect the strength of the spark, especially with an electronic dizzy. I haven't had time to read through all the posts, but it might pay to check the altenator brushes to see if they are worn. Marc.

Have you checked the ballast resistor? Not sure if that's causing the problem, it's sounds as though you've tried just about everything electrical. I have a similar problem with the L28 in my 240z that I'm building at the moment; when I start it, it runs like crap, misfiring pretty bad.... I decided to disconnected the battery while the motor was idling (very roughly) and the revs picked up and the motor ran really smooth....I then reconnected the battery lead and the revs dropped but the motor ran smooth.... Not sure why this is happening, could be that the battery (not standard) I've put in the Z is way too big or the voltage regulator isn't doing it's job. Not sure if this will be the cause of the problem, but are the tappets correctly adjusted? If you're willing to make the change, get your hands on an electronic dizzy; much better than the points system.