olzed

Wallace and Grommet remedy?

Good things take time

Another Approach. Power From Revs. Most if us will have heard about gobs of power and torque being extracted from a stroker engine. For those who don't know, a stroker is an engine that has been given the benifit of a longer stroke,that is the crankshaft throw, which gives more leverage to each turn of the crankshaft. This is usually achieved by fitting an aftermarket crankshaft, having your standard shaft welded and ground, or in the case of the Nissan 280Z, fitting a Nissan Diesel engine crank. By a happy chance the bearing diameters are the same for the petrol and diesel engines. This crank, accompanied by extensive head work to improve air/fuel flow through the engine,as well as careful matching of pistons etc. can result in huge power gains. The Standard L28 engine has a stroke of 79 mm or 3.1 inches, while the diesel crank has a stroke of 83 mm or 3.26 inches. These engines have become the way to go for your Z racecar. Another way to approach the subject is to make power from revs, not unlike the formula one race cars, producing in excess of 700 HP from a NA engine reving past 17000 RPM. The following is an extract from a magazine long out of print. "Most small capacity European cars make their power from high revs, and I wanted to move in this direction with my 240Z What most of these engines have in common is a short stroke of 3 inches or less. This keeps mean piston speed at a reasonable level at high RPM, ensuring that the engine will stay together and give a long service life. The high rpm generates power out of proportion to its displacement, because it allows the engine to transform the energy contained in lots of fuel/air mixture into mechanical work in a short period of time. The downside is that the short stroke reduces the engines ability to produce big torque by shortening the lever- arm length that the pistons and conrods act on to turn the crankshaft. My 240Z engine, with a stroke of 2.9 inches, came in nicely under the 3 inch limit. Not coincidentally, the stroke of the most popular hot rod engine known to man---the early small-block Chevy V8--- was exactly 3inches.The L24 block gives us 2.4 litres. It occured to me to use my L24 crank in a L28 block, which with a rebore of 1mm gave me 87 mm and a displacement of just over 2600cc. I knew that this would need careful thought about pistons and con rods if the deck height ( the height of the piston tops in relation to the top of the block) was to be right. Since I was to use the 240 crank, why not use my 240 rods? But which pistons could I mate with them? Using 280Z pistons would have worked, since the piston pin to piston top dimensions are the same in all first series Z engines. But there was a problem. Almost all 280Z and ZX pistons are dished on top, reducing the compression ratio below the 10-1 that I had in mind. However non turbocharged 280ZXs that were sold from 1980 till the end of the ZX run had pistons with flat tops. These fitted my requirments for low cost, since stock Datsun pistons would be far cheaper than forged racing pistons. I decided to use the E31 head that came off my engine, since this head has large ports and good quench characteristics between the head and piston top. One problem is the E31 combustion chamber is relatively small, giving more than the 10-1 compression that I wanted. Another is that the E31 uses smaller valves than later Z cars.The solution was to have installed the larger 280Z valves, and unshroud them by removing small amounts of metal from the combustion chamber near the valves. This improves breathing and at the same time lowers the compression to the 10-1 I was aiming at. All of this requires careful planning and execution with expert advice. Best to talk to a machinist who specialises in this type of performance engine rebuilding, preferably someone with experience in Z car engine rebuilding. Installing the larger valves requires machine work to replace the valve seats- an exacting process. The costs for this can add up. If you do not require the ultimate in engine breathing, settle for the stock 240 valves in the large port E31 head. It is possible to purchase an L28 block for very little. If you start with an early 240Z engine all you need are parts from your donor engine, an L28 block, pistons from Nissan or an aftermarket source, and a good machine shop. I had a 280Z camshaft reground, with considerable overlap and opening duration. I have run this engine freely up to 7000 rpm hundreds of time over the years and it's bullet proof. With the use of forged pistons and high qualiy rod bolts etc this engine will happily rev way past that and live."

E mail sent Ted. Good luck with it. Brian.

There will always be a small number of people on these forums that will try to make themselves feel better and all knowing when they have 'done it all before' and 'thats old hat'. We all know the benifits of long stroke and big bore. This guy wants to do something different without spending a ton of dollars. What I can't understand is why, when there is an enthusiastc young guy, crazy about our hobby, who wants to have a go at building an engine of his own, that doesn't quite fit what you all regard as the best way to make a performance engine, someone virtually calls him a wanker. Yawn.

I have it on email. pm me your address.

I doubt that you would get a back copy now Ted I think the magazine went out of print some time ago. I guess you can try. The Magazine is called Z Car Magazine . Issue Nov/Dec 1997. The article is called One Mans 263Z. 280Z block 240Z crank= power and revs. If you have no luck send me a PM with your email and I will copy it for you. It's rather lengthy but you would not need the whole thing. The same guy was experimenting with triple SUs on the same engine, but had not finished when the article went to print. Brian.`

Ted. I remember this same modification from a Z Car Magazine from 1997. This guy wanted a engine that could make power from revs. I won't quote the article word for word, but the guts of it is--- 280 Block 240 Crank 240z Rods Non Turbo 280ZX Flat top pistons 240 E31 Head Install larger 280Z valves, and unshroud the valves by removing small ammounts of metal in the combustion chamber close to the valves. This improves breathing as well as lowering compression to 10.1 1 He stated he regularly takes it to 7000 rpm, and it's a blast to drive, although it needs to be kept 'on the boil' A stroke of under 3inches is desirable for keeping mean piston speed at a reasonable value at high RPM, and for ensuring an engine that lasts. Same as what you are proposing only some valve and head work.

Can you find a reducer fitting at a hardware store and put that on with a short piece of rubber tube first. 1/2 inch to 3/8. Or braze or solder two pieces of steel or copper tubing together and make a reducer. Not hard.

Nothing tatty there. Very sharp.

Nothing 'tatty' there. 'Godam thats one hellava nice lookin ride you have there.' The Healey is a classic shape. Like the S30 it is so appealing to the eye. When I was a young fella a few years ago, the first 240z really appealed to me, as did the Healey. We had three kids by then, so any thoughts of owning either went on the back burner for many years. Finally 12 years ago at the age of 55 got my 240. The Healeys still command twice the price of a Zed down here, so that was definately not on my shopping list.

No 70s dodgy electronics to try to sort though.

Simple solution. Bolt on a set of SUs from a 240. Brian.

Any air bubbles when its running,or oil in the radiator?

So it seems we have agreed you should do the wheels either silver, or if the budget allows, chrome. If it were me I would choose silver, just because it's way cheaper.

After I changed diff ratios, I found it was a case of trial and error finding the correct speedo pinion. Luckily I have a friend who had an assortment.

You hit the nail on the head. There is still some snobbery lingering . God knows why, BTW your wheels look great the colour they are. Chrome would be my choice but I imagine an awful lot of work.

These engine need fuel when cold. The chokes are there to use when cold. My stock 240 stumbles badly when cold, but is fine when warm. Takes six or eight minutes.

Thanks Chris.A bit like a slide hammer. Mine is a stock plastic/wood wheel..I must have another go as I want to refurb it.I wonder how the guy who started this thread is getting on with his wheel. Brian.

Well i've been trying on and off for years to remove the steering wheel on my 72.I tugged and tugged that sucker and attacked the wheel with a hammer. No Joy. Ive hit the sucker while tugging, and still it won't budge. There does'nt appear to be any way to fit a puller withought doing some damage, so she stays put for now. I am probably lucky it didn't come off because I had taken off the nut. It would have laid me out.

If you want simplicity, then the 240 hands down. Carbs are simple, and unlike 35 years old EFI very little to go wrong. My 2c

Could you find some off another make at pic and pull.

Regardless of the master cylinder, the adjuster should still be able to lock the drum when screwed out. Seems to me he has two problems here. Problem at the drum and problem at the master cylinder or the wheel cylinder. Unscrew the adjuster fully out and wirebrush the threads.

Silly question, but are you turning the adjuster for the rear brakes the right way. If its all the way out you should not be able to turn the drum. Just another thought, perhaps the brake shoes are not the correct ones. Do they look to be the same diameter as the origionals. Another thought. Can you mesure the ID of the replacement brake drum. It may be way oversize, or it may be cracked. It could then expand as you applied the brakes.

Remove the grease nipples and see how it goes.