Fuel injection or carborated?

[Prest's Zcar]

I have a 280z engine and both a fuel injection setup and a carboration setup and I don't know which one would be better. What are the pros and cons?

[Arne]

Which is on the car now? And which are you most familiar with maintaining?

[TBone028]

I think you also need to think about what you want to do with your Z. Will it be all show and no go? Or do you want to actually get some power out of your L28? Also, what car is this going into? 240Z, 260Z, 280Z?

My Opinion:

Factory EFI, not bad, but as far as performance, leaves much to be desired and is often replaced.

Carbs...finicky, a lost art, and a pain in cold weather. That being said, SU's are probably one of the best types of carburetors ever built. I have them on my stroker.

[Prest's Zcar]

Which is on the car now? And which are you most familiar with maintaining?

The 240 engine is in the car now, but I have to rebuild it becuase the compression is bad. So I have to test the compression in the old racing 240 engine I have and if that is good than I will either put it in or the 280 engine that I have. I don't really have experience maintaining either. What are the major differences?

[Prest's Zcar]

I think you also need to think about what you want to do with your Z. Will it be all show and no go? Or do you want to actually get some power out of your L28? Also, what car is this going into? 240Z, 260Z, 280Z?

My Opinion:

Factory EFI, not bad, but as far as performance, leaves much to be desired and is often replaced.

Carbs...finicky, a lost art, and a pain in cold weather. That being said, SU's are probably one of the best types of carburetors ever built. I have them on my stroker.

Well I want to be able to show it off, but mainly I wanna be able to drive it. I definatly prefer speed over looks. It will be going into my 240z car. So you think that carbs are still the way to go? Does the fuel injection just not add enough for the hassle?

Edited April 13, 2010 by Prest's Zcar

[TBone028]

If you are putting this L28 into your 240Z. You will need to do a whole lot of work to convert to EFI. Just to start you will need things like:

1) ECU

2) High pressure fuel lines

3) High pressure fuel pump

4) running all the associated wiring for 6 injectors and various sensors

The list goes on. Once you get your 240Z ready for EFI, get the L28 transplanted and hook everything up...cross your fingers and assuming it runs...then:

If you decide you want more power from the L28 (i.e. cam, headwork, etc) you will find that the antiquated factory EFI will not know what to do with the increased fuel and air you've introduced. Your gains will be minimal if anything at all.

That being said, lets take your L28 (assuming its got solid compression), drop it in your 240Z, send your SU's off to Bruce at Ztherapy, bolt them onto your 240Z intake manifold and run that with the L28...you will be surely happy.

Later down the road if you decide to put in a hotter cam, swap the head from the race engine you have to up your compression ratio...your SU's will still be up to the task of feeding the engine (for the most part). There are a lot of resources on hybridz.org that can give you some great inspiration for whatever route you want to take. I would look into what kind of block and head combo's you currently have at your disposal. There is a chart somewhere around here that tells you all the different combo's and what kind of compression ratio you can expect. 9:1 or 10:1 is pretty aggressive for the street. From what I'm reading, you have 3 engines available to you. Thats a lot of different possibilities.

I'm not even touching the tip of the iceberg by the way, I have no idea what you have, your mechanical skill, or resources available to you in Montana. Personally, I think EFI is a fantastic thing. I would like to eventually convert my carb'd stroker to individual throttle bodies and use something like Megasquirt n' Spark for control. It would not only give me more power, but mainly be much more reliable and smoother in every way. What I'm saying is that the factory EFI is NOT the best option when planning for more power. What I'm saying is that strictly from the options you listed (Factory EFI or Carbs), I would go the carb route. The only caveat: Sidedraft carbs like SU's are a lost art. You will most likely not find a local shop that still knows how to work on them and you would have to do the service/maintenance. Just something to consider.

Good luck with your project, hope to hear some updates once you decide which direction you go.

Edited April 13, 2010 by TBone028

[Bruce Palmer]

I know I've covered this before and I apologize for the repetition. We have, over the past several years, helped injected Z car owners convert to SUs setups for the simple reason that they are simple and reliable. Seems the 30 something year old injection pieces are aging and the prevailing attitude we hear is that the owners don't want to hang around and wait for the next foible to leave them standing beside the road. Hence, a complete carb setup, get in hit the key and drive off down the road.

I still marvel at the interchangeability NISSAN has engineered into these cars........

Edited April 13, 2010 by Bruce Palmer

[Prest's Zcar]

Thanks guys I really appreciate it.

[Zs-ondabrain]

I'm with Bruce on this one. It's a 240Z, do the SU's. Or better yet, do the 280Z motor with SU's for a little more power and reliability. And I would definately suggest you look at www.ztherapy.com for their SU set-up. *Best in the business*, as far as I'm concerned.

And they work fine in cold weather, that's what the choke is for. That and a garage.

Dave

[Prest's Zcar]

So what is wrong with the fuel injection systems? Are they just not as good?

[Zs-ondabrain]

Nothing wrong with FI. But it's a 240Z, Barbs are a "Snap" compared to FI and all the wiring, fuel, AFM, Computer, etc, etc.

Carbs include 2 carbs, linkage, 2 fuel lines, manual pump and an air cleaner. That's about it. No TPS, CSV, AFM, Injectors, throttle bodies, many vaccum hoses, electrical connectors from hell, computers, hi pressure fuel pump and lines, and the list goes on.

He's looking to get the car on the road, he's got 2 motors and it's easier to pop in the 2.8, carbs, header and call it done. No offence intendid, just pointing out the obvious, not pokin fun.

Have a great week,

Dave

[TBone028]

Modern fuel injection is great. But, based on what you asked, most people would say the 280Z fuel injection is outdated and will be a lot of work to convert over to your 240Z.

If you're still kind of hesitant, order the DVD "Just SU's" from Ztherapy. It will give you a great idea of how they work, and how to service them yourself. From there you can decide on how difficult it will be for you to maintain yourself. Chances are that if you send your current carbs to ztherapy to be rebuilt, once they're on you wont have to touch them for a very long time.