Thanks for the prompt responses. But I am still confused because several sites have info indicating that the L28 makes less HP!?

For example this one: http://www.datsuns.com/datsun_dept-mainpage.htm

and this one: http://members.aol.com/KarlWS/zhistory.html

"1975 - Needing increasingly complex technology to meet even tougher emissions regulations, Nissan boosts the Z-car’s displacement to 2.8 liters and adds a version of Bosch’s L-Jetronic fuel injection, creating the 1975 280-Z. Horsepower rating is increased to 149. "

Excuse me for being redundant, but I would like to obtain accurate info. Also,, does anyone know the weights of the 240z and the 280z? A link with some comprehensive info would be greatly appreciated.

Cheers,

Art (in San Francisco, hence SFART)

The rated HP for the early Z-cars bounced up and down over the years, and the rating system used was not always the same either. So direct comparisons are difficult at best. The following list is from memory, so don't hold my to this.

Factory claimed HP

1970 - 150

1971 - 150

1972 - 150?

1973 - 129

1974 (L26) - 139

1975 (L28) - 149

1976 - 149?

1977 - 170

1978 - 170?

Side note - the '71 240Z I am picking up this weekend has an injected L28 (from an '83 280ZX) in it now. No idea how much power that was claimed to make. But I suspect I will eventually yank the injection and revert to carbs.

The '77 L28 is the one to go with huh? I had no idea. Then maybe instead of swapping in a 280zxt L28, I might go for a '77 L28. I prefer to keep my engines N/A.

My 240 weighs in at 2300 BLS with 5 gallons of gas. The `70 240 was reported to have a weight of 2250 and by the time the last 240's were out the weight had gone to around 2400. The later Z's like the 280 weigh around 2700 or more. A friend of mine has an ~82 ZX that weighs 3300, it is a real pig.

The '77 L28 is the one to go with huh? I had no idea. Then maybe instead of swapping in a 280zxt L28, I might go for a '77 L28. I prefer to keep my engines N/A.

But bear in mind that they may not have been rating those engines the same way, so the differences may not be what it looks like.

This has been beat to death in other threads, but...

The advertised horsepower ratings of cars sold in the United States before 1973 is SAE GROSS. This is the power measured at the output shaft of the engine on a dyno stand, with no accessories...

The advertised horsepower rating of cars sold in the United States from 1973 on is SAE NET. This is the power measured at the rear wheels with the engine in the car, using the stock exaust, with all accessories connected.

That is why the HP fell from 1972 to 1973.

All other things being equal an L28 will always make more power than an L24. You just can't beat displacement...

By now, some 20 to 30 years down the road, the most significant issue with any L28 isn't the year of the car it is in when you recover the motor. The real deciding factors are the engine's condition, and what was done to it before you came along...

There are VERY FEW Z cars that are actually still running the ORIGINAL engine, without at least a rebuild...

Yank the engine and drop in a small block V8... Personally, I'd put in a HP 327 with a Carter AFB and 2 1/2" dual exhaust...

L24, L28, either way, they are 25 to 30 year old engines, unless you rebuild the engine you probably wont get near the rated HP.