ZCar Forum banner
Status
Not open for further replies.
1 - 11 of 11 Posts

·
Registered
Joined
·
35 Posts
Discussion Starter · #1 ·
Hello folks. Let me start by saying I think it's very cool to have a place like this to come to for Z info. I'm a new owner of a very sweet 1972 240Z that is probably 98% restored and I am totally in love with. I used to own a 1978 280Z that was not nearly as nice as my 240, but owning that car made me fall in love with the Z-car and I've wanted another ever since, and now I have one.

So like I said, my 240 is 98% restored - there are very few things left to do to make it perfect, and I credit the previous owner for the work he did. Since I bought it in September (on E-bay), I've replaced the entire front end - steering, brakes, struts, brake lines, pretty much everything. I've also had other minor work done to get it where it is.

I've still got several issues that I'm trying to solve - but one thing at a time.

My first question would be about fuel economy. Let's assume my Z's L24 engine is tuned properly (which I think it is because it runs incredibly smooth w/o any hiccups), what should my mileage be? I've been putting 93 octane in the tank and have gotten no more than 15 miles/gallon. Does this sound normal?

edit: I thought I'd include a link to my car's pic :)

 

·
Registered
Joined
·
1,078 Posts
Welcome and wow she is nice!

Yeah I am new too and I got to agree this site is great but its the people that count too that have helped me loads already.

I've got a 240Z 73 but I haven't had her long enough to tell you what mine does, a stock one though should do approx 20.8mpg.

Best of luck with her.

Jules
 

·
Registered
Joined
·
645 Posts
Indeed, very nice

always liked a nice mettalic finish...

anyway, like 24OZ said, something just north of 20 mpg should be achieveable. when my motor was stock i remember getting something like almost 22 mpg if i drove it nicely. what could be making a difference is the tranny and rear end if they are not original. what are your revs at 60? at 80?
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #4 ·
Re: Indeed, very nice

If I go through an entire tank on the highway only I can get 20 mpg. Unfortunately most of my miles are short trips. As far as I know the tranny and rear end are original.

At 60 mph the car is doing 2650 rpm, and at 80 it's at 3450 rpm.
 

·
Registered
Joined
·
1,298 Posts
Re: Sounds about right...

I just got mine back from the mechanic, so I can't give you numbers as to mpg.

One thing he did mention that he considers crucial, is the adjustment of the valves. He mentioned that the engine can seem to be perfectly adjusted, but that if the valves are out of whack, your mpg will suffer.

I can tell you that since the carb transplant and the distributor fix and the adjustment of the valves, the car runs like a scared ape.

No doubt with the level of restoration you've had done, this was most likely addressed. If it's been a while since it's been done, I would heartily recommend it, it made a world of difference on my car.

FWIW
 

·
Registered
Joined
·
4 Posts
This is my first post as well. I'm looking around on behalf of my sister.
You see, she owns a 1973 240Z but has no mechanical knowledge. I own
a couple of Mercedes cars and do some work myself but have little time
these days. Anyway, my sister's car had a clutch problem; the master
cylinder failed. It sat for a couple of months before I fixed it the other day.
Now the car works and is very fun to drive. There are still problems, but
in time we will get it working great. The next job will be to check the
transmission rear seal and then those carbs.
Her car was made in July 1973. Would that be one of the last 240z's?
Thanks,
VR.
 

·
Registered
Joined
·
1,175 Posts
I get a little over 20MPG driving normally. Normal for me means flooring it up steep hills and lots of fast takeoffs. Your carbs could be running too rich. What do your spark plugs look like? Are they turning black? I would highly recommend picking up the tuning video from ztherapy.com. Your distributor could also need adjusting. The points get out of adjustment pretty easily and you wind up not getting consistent spark.

Very nice car!

Also.. unless your compression has been raised or your timing is really advanced, you shouldn't need 93 octane gas. I've been using 87 with no pinging.
 

·
Registered
Joined
·
35 Posts
Discussion Starter · #9 ·
Great stuff peeps. I know the car had a basic tune b4 I bought it in September, but I'm unsure about the valves, timing, and distributor. I put new stock plugs in shortly after I bought it because the old ones were blackened. I'm suspecting that the mix is too rich, therefore hurting my mpg. I also wonder how much extra fuel is consumed when the choke is out while warming the car. Obviously that doesn't help mileage, but this car doesn't want to go anywhere when it's cold, let alone even start so I have to use the choke. Seems like a proper tune is in order.

Thanks to everyone that replied!
 
1 - 11 of 11 Posts
Status
Not open for further replies.
Top