I've decided to switch to SU carbs!

[beandip]

Walter That really makes me chuckle . Just climbing into a early Z is steping back in time ! HELLO . Dont get me wrong I love my Z , The styling the sound and the way she performs. But it is old tec from one end to the other. A manual trans is old tec as well. So SU carbs fit right in to the whole package. There VARY simple and work well. Just my 2 cts. Gary

[sonofzzzap]

I'm gonna add another comment...

I am a College Student, I work 2 jobs..(one at our Country Club in the golf division and I am a part-time substitute teacher)... I do not pull in money like those of you with FULL-TIME paying jobs....

My situation... the EFI in my 1977 280Z is very "out of whack". It has been tampered with and rigged without attention to perfection..... In order for myself to go through the ENTIRE system... I need one thing... $$$. EFI replacement parts are expensive.. (and in order to do a good job redoing the EFI, I would need to buy good new parts...).

Lets face it, money is something I do not have.

Why carb my 280Z?? its simple... well.. Yes it is simple! I would consider switching to carbs a "bang for your buck" method... why? because not only does this set me up for more less expensive performance but it is simpler to maintain IMO.. I have read the pros and cons for this switch, and I have recieved much NEG feedback... but the PROS I get from the few that actually supported my idea were great... I'm looking for budget performance... and I believe in SU carbs.... Therefore I want to undertake the project...

I'm still getting NEG responses... and I really want to do this...

[san_maru_zed]

I respect the idea but since you already have F.I I think you should stick with it. There are certain year(s) of E.F.I on 280z's and ZX's that are better set up's than others and you can get your Z going just as well as on carbs if not better with F.I.

There will be a whole heap of wiring you will need to remove from your loom and it could get very confusing very quickly.

Just my opinion.

Hey Gav, care to elaborate on the certain years being better setups ??

Ray

[Gav240z]

Well i don't know the years but i know the manifolds when i see them. They are good for porting out and if you fit them with bigger injectors they work really well. As I say im not sure which year is good i just don't work on ZX's often enough. There is also a really good distributor off a ZX which i'm still not sure what year it is off. I would like to find out for myself so I can get more of them. I don't have it handy with me at the moment to give a part no.

Sorry i can't be of more help but I have seen a few people on Ebay in the US selling ported out manifolds and bigger throttle boddies and custom fuel rail kits that looked like they would work really well.

[sblake01]

There were slight differences in the electronics as they went from 75 to 83. The basic system was about as refined as it ever got in 77. Things like the injector fan were added in 79 on the ZX but I've never really seen any real proof that it really provided any benefit. The location of the temperature sensor changed in 79 on the ZX and at the point the BPT valve was no longer used. I really wouldn't suggest mixing components from the different years. The ECU for a particular year is designed to work with the components in the particular car. There is a label on each ECU warning of potential damage if it used in the wrong year car. The other items you mention such as bigger throttle bodies, custom fuel rails etc. as well as rising rate fuel pressure regulators, bigger injectors (unless you use the turbo injectors) are aftermarket parts and any head or manifold can be ported.

[CoastGuardZ]

On the topic of money...

Z Therapy (renound as the best bet) get's $595 for the SU's + $150 for the core charge unless you just happen to have a set of round tops kickin' around. Then you have to get the manifolds and the N42 cylinder head. What if the head needs some work? Valve job and what not. You also need a new gasket set, air cleaner(s) and probably a couple runs to the parts store and/or salvage yard for misc. bits and pieces. Don't forget setting up a choke to get the car crank without problems. Sounds like to me you'd be into the carb conversion for close to $1000. I haven't bought pieces for Z EFI's but I would think you could replace all the sensors on a primitive FI cheaper than that. And then there's always MPG...hmmm.

Good Luck either way you go.

Nate

"Money & Time... NEVER enough."

[sonofzzzap]

You guys are right... Considering that my car is EFI I should just deal with it and work out the kinks.... I still like the idea of SU's, but I believe that would be more of a side project perhaps something in the future?...

I spoke with a mechanic friend of mine last night, he has worked on many Datsuns since 1980 and he reccommended that I go through the system, one section at a time, and re-work it, perhaps get a better fuel rail and replace several things...

So I have accepted EFI as my option...

I'm wondering... Are their any EFI performance references that I could take a look at? I have thought about buying the book "How to modify your Datsun OHC engine"... Ive heard it was a good reference, but it doesnt mention EFI..

Also, I have a 78 280Z 2+2 parts car, would it be safe to use EFI parts off of it? Just curious.. the only reason I got it to begin with was so I could steal the fenders and hood.

thanks guys

-Jared

[CoastGuardZ]

Jared,

Great book about mechanicals and a good bit on Carbs...

As far as EFI goes there are a couple of pictures on Pages 8 and 9 of a custom system by Devendorf. And that's all that it is referenced.

Take care and good luck

Nate

[sblake01]

77 and 78 EFI parts are the same.