Getting the most power

[e_racer1999]

to answer your last question, people bore out the L28 blocks to 89mm for the 3.1L motor. usually they use the F54 block because it is arguably a bit stronger.

but the setup that i'm going with is similar to daniel's, and i think it's a pretty darn nice, quick street setup.

i've got an F54 L28 block with flattop pistons

N42 head, milled slightly & mildly ported

stage III MSA cam with valvetrain

MSA 6-1 header into 2.5" exhaust

albiet i'm going through SUs, i think it's a good setup. i think that you can build something up pretty similar for around 1500 if you do the work yourself. stout combination, and you can use your same block and crank....

[240ZMan]

I'll just add to Jason's comments that if you're on a budget, you can have your current cam and followers reground/resurfaced. I did that with Delta Cam and spent around $125. I was able to keep my stock springs too. The cam has .488" lift and is spec'd at 284 degrees duration (don't know what it is at .050 lift). If you done your homework with the bottom end, and have the breathing in and out of the engine done right, the cam really wakes the engine up. Of course, this all assumes your head is in good condition, including the valves, seats, and springs.

Like I said, for that small amount of money, you get a lot of bang for the buck.

[AndysPlit]

Okay, so let's see here. An F54 head is from the last 280ZX motor, right?

Judging by the previous posts it seems that either way I'm going to have a different engine if I choose to upgrade in this vein. I suppose I'm being sentimental over the original motor. But if I want to build it up the right way, I am going to to be borrowing from various L-series engines?

Forgive me, while I digest this in. I think I have been under an illusion.

Thanks for the bore specs Jason!

to answer your last question, people bore out the L28 blocks to 89mm for the 3.1L motor. usually they use the F54 block because it is arguably a bit stronger.

but the setup that i'm going with is similar to daniel's, and i think it's a pretty darn nice, quick street setup.

i've got an F54 L28 block with flattop pistons

N42 head, milled slightly & mildly ported

stage III MSA cam with valvetrain

MSA 6-1 header into 2.5" exhaust

albiet i'm going through SUs, i think it's a good setup. i think that you can build something up pretty similar for around 1500 if you do the work yourself. stout combination, and you can use your same block and crank....

[AndysPlit]

I meant to regard the F54 as the block to clear that up.

[240ZMan]

If you are starting from scratch, then the F54 block is more desirable. But MANY people (yours truly included) have used the N42 block with excellent results. Unless you are going to go for outrageously high revs, or lots of boost with a turbo, you would be fine with your existing N42 block.

[AndysPlit]

OK, now that's a relief! I thought things were going to get more complicated than I imgained. Just for reference does anyone have a link or file that is a cutaway view of the L28 engine? That would be great.

Thanks!

If you are starting from scratch, then the F54 block is more desirable. But MANY people (yours truly included) have used the N42 block with excellent results. Unless you are going to go for outrageously high revs, or lots of boost with a turbo, you would be fine with your existing N42 block.

[mars23z]

Whats to say you cant just use what you have and get the big bore kit from msa? a little pricey but you keep the engine here is the link

http://www.thezstore.com/page/TZS/CTGY/PEM05

[e_racer1999]

just for personal reference (this also works into a recommendation for AndysPlit), would the KA24 pistons with the 240Z rods work without turning them down if the stroker crank isn't used? if so, that would certainly be an economical big bore upgrade.

[Curtis240Z]

Is laptop programmable triple throttle body fuel injection over the top? I have pictures in my gallery.

[GunnerRob]

Hi Andy,

I don't mean to throw a turd into your punch bowl, but how do you intend to pass smog with these modifications you are thinking about doing? Don't get me wrong, I feel you should be able to do whatever you want too your Z, I'd just hate to see you go through all this planning, financing, and building a hot car to find out you can't get California tags for it. Just a reality check.

Or... Are you going to build a track car?

Rob

[Curtis240Z]

Won't next year be the magic year for Andy? His '78 will be 30 years old and his Z will be exempt from smog because of some CA historic rule?

[AndysPlit]

Unfortunately as it stands now, the California smog exemption stops at 1975 cars. I have heard that they do not plan to go beyond that year in the furture. I hope that the law will change, but as it stands now it doesn't look very good.

Maybe a 240 was the way to go.

Won't next year be the magic year for Andy? His '78 will be 30 years old and his Z will be exempt from smog because of some CA historic rule?