TheCrazySwede

So, I gave Rebello a call (Turns out they are about an 1 hour away from where I live!) I asked him what type of pistons he recommends. He said he hasn't faced many issues with the flat-tops in the N42 head, but if a higher compression isn't needed, he would recommend the dished ones. I also asked him about valvetrain improvements, and he recommended a mild cam with a rather low lift (about .448) but he said that the Cam produces great torque and works great for street use. He said that Z Car Garage (Another highly rated Z specialty team) prefers that Cam Kit over most, mainly due to its power delivery. I'm going to go over to Rebello (bring my head!) later this week, probably on Thursday, and see what can be done. They use ITM Pistons, by the way.

Hmm, that is a head scratcher. Given that this is my first build, perhaps it's better for me to be better safe than sorry, I suppose. Yeah, we only get 91 octane here in California (aka Commiefornia)...I've never used those octane boosters, so I don't even know if those things actually do anything. Back home (I'm from Sweden, in case that wasn't obvious, haha) we had up to 98 Octane at almost every gas station. That sure would be helpful over here! What do you guys think? Is it worth it to go with the flat-tops? I was gonna call Dave Rebello and ask him what type of pistons they have (I know they have dished ones for N42 heads.) I was going to order my valvetrain upgrades from him anyway.

Thanks a lot for the links, madkaw! Thanks for the input, Jeff! Triple Carbs is something I want, rather than something I need. I already have a pair of SU carbs rebuilt by Rebello (Sold along with the motor when I bought it) so I'm already set in that area. TW's is something I'm going to get more down the line. Thanks for the tip regarding the harmonic balancer! These are things I would like to know regarding the build...things that have been learned through experience. I appreciate you sharing your knowledge! I'll definitely keep that in mind, now. I messaged someone from HybridZ who is very knowledgeable about L28's and their different builds, and he advised against getting flat-top pistons in an N42 head, and instead, told me to keep the dished ones. He told me that time and time again, he's seen the flat-top swaps done and have seen the effects of detonation in the head. The power gained from the extra compression is therefore lost due to the need to retard the timing. Since I'm keeping the stock valves and aren't planning on boring anything, I think I should heed his advise and keep the dished ones. As I mentioned, power isn't too much of a motivator. Reliability and responsiveness is what I want. A lighter flywheel is up there on the list! Thanks a lot, again, for all of your help guys! It means a bunch.

The only flat tops I found were 86.1mm (ITM Brand) Also, I won't have any problem with clearance switching to flat tops, right? Just want to take precautions...wouldn't want to hit the valves or anything.

I'll probably end up going that route. The only other thing I wanted to change were the pistons. Are there any flat-top 86mm pistons I could use with the L28 rods?

Again, thanks a lot, gentlemen, for your inputs and suggestions! It really means a lot. I'm glad there's such an awesome community available out there that allows us new-comers to pick up and learn the ropes. Thanks guys!

If that is the case, then I suppose you're good on that end! Let us know how your pressure is like. Should be around 36-38psi if I remember correctly. It should rise to 40-42psi when turned off if your pump and regulator are working properly...

Thanks for the replies everyone. I should note that I am in no rush with this motor, so I can take my sweet time learning everything I need to know before purchasing and swapping parts. That's why I wanted to consult you guys, first. Price for me isn't too big a factor. Money = Time. The more money I spend, the slower the build, haha. A part of me doesn't necessarily want the simplicity. I already have an L28 in my 280z that pushes enough power (completely stock) to satisfy my needs. Want I want is a build that is different, behaves and acts different, from my original 280. That's why the idea of the L24 crank sounded intriguing. Wouldn't a setup like that alter the compression ratio dramatically? I may very well do what you suggested (Stay with the L28 parts) and move onward, but I don't want to brush off other build ideas only because this way was "easier." I want the build to be something I want, rather than something I had to go with, if that makes sense. I remember boring my 289 in one of our Mustangs and going with bigger pistons. I didn't really notice much of a difference, honestly. At least, not for how much money it required. I guess I wouldn't have much of a choice if I wanted the higher compression from the flat-top pistons.

Yup, flat tops and triple weber carbs are on my wish-list! I've seen a few builds with L24 crank and rods, with flat tops from the L28ET. What's the reason for the L24 crank and rods? Is it the stroke ratio? I don't know what differences the ratio will give. If want a rev happy and responsive motor, would I benefit from the L24 crank and rod? Or should I be fine with my L28 equipment and just get the flat tops?

UPDATE: 2/14/15 After a rather long hiatus, the build returns with updates! As some of you may know, I decided to go with the professionals with this build. Looking at some local shops around my area, most notably Rebello Racing, and also some other shops across the country, I've decided to send my dear L28 out to Eiji Hosomi at Datsun Spirit Inc. (https://datsunspirit.com/) There are three main goals that I wanted my motor to achieve. 1. Speed > Power. I want my motor to run like a hot knife through butter. It needs to be quick and very responsive. Power is nice, but a quick revving motor is what I seek. 2. Character. My beloved Z will eventually be my weekend car. I don't want the motor inside of it to just be a fast engine. It needs personality and character. Something that sets it apart from, let's say, a Honda Civic. This is why I went for triple Weber 45's, a flywheel that weights less than 10lbs, and my desired cam (more info on those later.) There's a certain character I want this motor to display, and I believe this build fits the bill just right. 3. Reliability. It might seem like an oxymoron, having a fast and reliable sports car motor, but I've seen time and time again how these motors, when built by true artists of their trade, can withstand almost anything you throw at them. My new motor will be running on pump gas, will idle smoothly and will barely break a sweat with the granny-like driving I put my Z through. Engine Specs: Bore/Stroke: 89mm/79mm Pistons: 29mm Kameari (280g) Rods: 139.5mm Kameari (~575g) Crankshaft: Polished, Stock L28 Camshaft: .290 Duration / .490 Lift Valves: New valves (stock size) Upgraded springs and retainers CR: ~10.5 to 11:1 Now, time for some photographs! Here's an album with all the photos I've gotten from Eiji thus far. I'll update it as the build continues: http://imgur.com/a/Fyqtv ORIGINAL POST: Dear Forums, I've been a long time lurker of these forums and of the community, but just recently, I've decided it was time I popped my Z cherry and got involved. I own a '77 280z (Motor has EFI; Transmission has 4 Gears) I'm currently working on another L28 that I picked up (Carbed, N42 Head) along with a 5-Speed, but due to my lack of knowledge regarding these motors (We are a family of Ford Mustang owners) I seek your help in order to make sure this build isn't a total disaster. To start off, hello; My name is Mike I am 20 years old and I'm a computer tech. This is my first engine rebuild, so experience is not really something I have in my corner. Luckily, my brother and my dad are both mechanics, but they decided to pretty much leave me to learn how to swim in the ocean with this build. My goals for this motor are pretty simple and straight forward, but I would still love to get some help from some of you more knowledgeable L-Series petrol heads. Let me start by saying that I am not power hungry. We have the pony cars for that. What I want is a responsive motor, not a powerful one. Engine Goals (Might get redefined as I learn more about these L-series motors) 1. I would like to hit 200HP at the crank (Although not necessary) 2. I want the motor to be naturally aspirated. 3. I love the look and sound of triple Weber carbs. 4. I don't think I need a stroker motor to produce a descent amount of power, so unless it's necessary, I'd rather not go there. Things that I am considering (Please correct me if I'm wrong!) 1. Balancing the Crank 2. Lighter, flat-top pistons (I would like to keep the stock 86mm size) 3. Stock valves look good enough! Probably just stay with those. 4. I've read a few posts where people mentioned using L24 rods. Why is that? Weight? 5. A Mild performance Cam with upgraded springs. As I mentioned above, I'm just learning about these motors, so your help is very much appreciated. I wouldn't know what to do without you guys. Also, I'm gonna post this thread over at HybridZ and see what those guys think. I'm gonna need all the knowledge I can get. So that's pretty much it so far. Cheers guys, and thanks a lot for the help! Not that it matters much, but here is the car: (It is currently undergoing bumper surgery!) http://imagizer.imageshack.us/a/img716/8786/014wzu.jpg

Does your AFM have the little adjustment screws on the side? Helps to tune it a bit. What size lash pads are you using? .175"+ is a bit too thick even for a mild cam. I assume you're at .160"? Have you measured your fuel pressure? See what your pressure is like. You should be able to place a gauge right between the fuel filter and the rail.

I'm using a N42 head. I didn't really have any desire to port my head, unless it became necessary. I would like to reach a 200HP number, although power is not really my goal. Instead, it's how it delivers the power. My current 280z has EFI, but the L28 I'm rebuilding is carbed. Triple Weber setup, lightweight flywheel and propshaft, along with a 5-Speed tranny and a diff upgrade already satisfies my needs. If I could dish out a little more juice out of the powertrain, I would love that, but I don't want to go out of my way to do it.

I'm glad to see you here, Diseazd, because if I remember correctly, you got your motor touched up by DSI. Things that I'm planning on my rebuild are mostly Cam (Including rockers, retainers, springs), new pistons and proper balancing (within 0.5 grams) I wanted to get the Kamaeri pistons (Pardon me if I miss-spelled that) that weight 160 grams lighter than stock, but I would like to keep the stock 86mm size. Could I expect a powerful L28 without a turbo or a stroker while keeping the bore the same? What are your guy's thoughts on the subject? Here are the current valves. The car had a broken head gasket, so there's a bit of coolant and oil running amok. Here are the dished pistons, that will get replaced.

Dear Forums, I'm currently rebuilding a stock L28. I was looking at the DSI Big Valves ($408) but was questioning myself whether or not it's worth it. http://datsunspirit....=dsi-big-valves The Intake is 1mm larger, and the exhaust is 1.5mm larger. Looking at my own head, I noticed that the stock valves are already pretty large, and was wondering if bigger valves are worth the extra dough and if they are safe. Also, on that website, it states that the valves are longer. What would I have to change to accommodate for the extra bit of length? I'm planning on running a higher lift cam, but it's still a mild cam and not some crazy .560 racing cam. What are your thoughts on this? Cheers!

Yup, been a member of HybridZ for a while now, but they aren't always as "patient" towards those who are new to the scene. That's why I prefer the community here. I'm more than willing to learn about it all, in fact, I am intrigued. I've been competing in motorsport since I was 4 (in karting) and I recently took up club racing and solo autocross. Everyone else has a much broader knowledge than I do, so I've been aching for an opportunity to learn more about the mechanics of a car, rather than just the handling aspects. Thanks a lot for the help guys, it means a lot.

So I've been told, haha. My brother and my dad are both mechanics (both own 60's Mustangs) and have a lot of experience with the subject. My brother tried to convince me to stay with EFI, mainly due to its simplicity, but I've always preferred the look and sound of carbs. Also, feels like there's a circle of hell every other classic car owner has passed except for me, so I figured I'd join. Jokes aside, they both said they'll teach me the ropes with everything. Also, I've got a Nissan/Datsun mechanic who lives a couple of miles away, so that's always an option, too. I appreciate the heads up, though.

Thank you for all the hints and suggestions!! Haha, I'm still trying to figure that hot restart problem out, but that is not the reason for this. I love the look and sound of a carb'd L28. I was thinking about doing what you mentioned, having the EFI stuff shoved to the side if ever needed. Wow, so not much required for the wiring? Glad to hear! I'm planning on getting three Weber carbs. The car comes with rebuilt SU's by Rebello, but I prefer the look of the Weber carbs.

Dear Forums, I'm planning on putting in a '76 carbed L28 in my '77 280 (currently running an EFI L28) Is this an easy drop-n-go or do I need a new harness? What else would I need? I'm picking the engine up on Friday. I am not very car-savvy, as my 280 is my first car to own, so please be gentle with terminology Cheers!

I hear ya. Yeah, unfortunately, good ol' Commiefornia won't let us pass on by in our classic Z's...unless mine was 2 years older, in which it would do just fine. I've read about the ZX's cooling fan setup and how it has managed to relieve a lot of issues regarding heating issues with these older Z's, but I've also read cases that object with quite contrary results. I don't remember specific threads or posts, but I've seen a few Z owners who have tried the ZX's cooling and still faced the same problem. Could this possibly be because of variable factors taking part in the issue? I don't see how a ZX's cooling fan could cure a leaky injector, for example. Given that cooling is the sole issue, would a ZX cooling system be the solution?

Haha, haven't heard that one before. I hope to get to the bottom of this whole issue.... Were you able to "cure" the problem with your setup? I'm not as car-literate as most of you here, so you'll have to be patient with me. I'm no stranger to cars, I grew up taking part in motorsport and I still do, but I was always more interested being behind the wheel than under the hood.

Aye, you are correct. I'm running with the factory exhaust manifold. I live in Commiefornia (CA) and I've had this issue occurring since around October of last year. The issue might have been present prior to that, but because the car wasn't my daily driver, I never noticed it. It is my daily now, so I've come to realize this issue. The car will run great otherwise. Even under hot weather conditions, the car will run strong and idle perfectly. Let it sit for 15-20 min (having it sit for 5 min does nothing) and it will act as if it's running on 5 cylinders. Capt. O suggested that I check my fuel pressure, so I did, and it gets proper pressure constantly, and maintains higher pressure when the car has been turned off as it should. I spoke to a Nissan mechanic last week or so about the issue and he thinks it could have something to do with the ethanol in the fuel and the mixture in winter fuel. He said that a lot of his customers that otherwise had no issues with their cars start to come in around winter time for this exact problem. I live in San Jose, and there's a great Z Specialty shop nearby (Z Car Garage) that I hope might figure something out. They are pretty popular, so I have to wait for my appointment date...which is almost 3 months from now :/

Hello, my name is Mike, and I have a hot restart problem :disappoin: 1977 280Z. Stock injectors. Stock Headers with MSA Twice Pipe exhaust. Car will run great, both in the cold and in very warm temperatures, but will have the hot restart issue regardless. I've noticed that the problem goes away if I rev the motor up to 2,000+ for a few seconds and then let it idle. I've tried revving it up to 1,600 and 1,800 multiple times, for much longer than a few seconds, and the problem would still be present. Could there be a reason for this?

I tried the coil test with the spark plug, and I got no spark I checked the wires from the rotor button, and everything was in good condition. I also checked the resistor and I'm getting power to that, as well. Not really sure what else to look for :/ I really appreciate the help guys. It truly means a lot!

Thanks for the reply EuroDat, I really appreciate it. I did download and read the FSM, but it didn't help me with much. I looked through my owner's manual and my symptoms fall under a bad ignition system, so I'm trying to trace down the problem from there. Yes, measured in just ohms. Hm, I have yet to try that. So, I can just take the ignition wire from the coil, disconnect the end connecting to the distributor and use a plug in its place? Didn't think of doing that! Surely, it will help in finding out the problem. If no spark occurs even then, it can't be my distributor or dist. cap, right? Heck, they might be a goner, too :S Can a faulty Ignition Module cause this? I've always heard of people having their car die on them while driving, then working just fine. That has never happen to me, so I doubt that's the case. I really appreciate the help. My 280 is my first car, and so I'm still in my learning phases of things. It means a lot, thanks.

I have a 1977 280z and I'm having some trouble getting it starting. I don't seem to get spark from any of my plugs. The car was working fine the other day, but suddenly decided not to work. I've had starting problems in the past, but I have been able to fix them with some good ol' starter fluid. That trick won't work this time. The engine cranks just fine (starter gets proper voltage, as well.) I've checked the battery and the connectors, all work fine. I replaced my ignition coil, and all of the wires (ignition wire and spark plug wires) and I've also replaced the plugs, themselves. Still, no spark. I checked the resistance of my distributor cap and I got around 0.9 to 1.2 ohms. I believe it is suppose to be near 0, but I don't know if my level of resistance is enough to prevent the car from starting. My main question is this; Are the possible issues in the distributor, the cap and the rotor? How could I accurately test each one? (I've searched Google, but I've fond a ton of different answers that are totally irrelevant. Maybe I'm not looking correctly.) What else could be causing this? Thanks guys, I really appreciate it. Cheers!