L28 in 72 240z...

[grantman240z]

has anyone here done this conversion? a rod just blew on my original L24 and the engine is frozen up and unable to be rebuilt/refurbished...so i am left with buying a new engine. i couldnt find anybody with a L24 but found a 1982 L28. Does the L28 with 72 SU's really make a difference in performance? the compression ratio is lower, but the engine is lighter. Im in a bind financial wise and since the L28 is cheaper, im thinkin about it...but if performance isnt as good ill just look for another L24...

[240znz]

A good place to start is http://www.geocities.com/zgarage2001/z.html

I've been sifting through loads of info on this and all I can say to you is..and everyone esle will as well ..do your homework and start a budget BEFORE you start.

Personally, I'd keep as much of the old L24 as possible as you never know if you will restore the car in the future.

[Daniel]

Yes,the L28 is used as replacement all the time.Use a 240 in/exhaust gasket.It covers the holes where the fuel injectors would have been.If you are using mech. fuel pump move over the fuel pump cam from the front of the camshaft.Everything else just transfers over.There are round and square exhaust port L28.That will determine if you can reuse your stock (square)exhaust manifold or if a shiny new header is in your future. HAVE fUN!! daniel

[redneck240z1]

Yes, you can put a l-28 into the 240Z. It is mostly a drop in for you. It will increase the horsepower/torque that you can use. Make sure the head you are using has got the bolt holes in it for the carb manifold. The 280Z E-79 head is set-up for fuel injection and has round exhaust ports. Change it to a square port exhaust head (E-31,E-88 or E-90). I have put this engine w/E-31 head into my 71 240Z. The L-28 block came out of a 280ZX with dished pistons. I have been able to run regular gas with it. I also use three 45mm DCOE Weber carbs on it with a mild cam. Head has been ported and polished with the big valves in it. For you the SU's should work fine. Good Luck, Rich.

[2ManyZs]

If you use an L-28 for the 75-78 280's you will get a better compression ratio with the flat top pistons. About 9:1 versus 8:1 (approx) with the later dished pistons from the ZX.

You can use the E-31 head for even more compression, but an E-88, N-42, N-47, P-79 will work just fine. The E-31 and E-88 will have the smaller valves but can be upgraded to the larger 280 valves.

[Ed]

I did the conversion myself a couple of years ago. Big differance! Make sure your mechanical fuel pump has a hole to go through on the head. I noticed some of the later heads don't have the hole in the head for a mechanical pump.