Is milage a factor when guys purchase a z?

[Edward]

Have been thinking about this for a while now going that these cars are like 30 years old now. Or milage doesn't matter?

[Josh280z]

Im not sure that many people get these cars for mileage. At least I never thought "hey, I know of a fuel efficient vehicle, a Z!"

[rturbo 930]

Doesn't matter. Not unless you're a collector. And if you're on Hybridz, I'm guessing you aren't.

 

Edit: didn't realize you meant fuel economy.

Edited March 17, 2014 by rturbo 930

[Tony D]

Exactly what is the question? It makes it sound like because cars are old, somehow their mileage must suffer? The Geo Metro's of old returned mileage figures not yet equalled in non-hybrids. The old B210's got nearly 40mpg at highway speeds despite turning 4K rpms.

 

L28ET's turned in low 30's when steady state cruised on the highway.

 

That seems reasonable enough for me. Exactly what kind of mileage is one supposed to get before one is classified as 'not caring about mileage'? My tow vehicle gets 8mpg when an inner dually goes low...compared to 10-12 otherwise... And towing? Pfft! It is what it is. 

 

I mean, really, what is the question being asked here, as there is an inference that is unspoken and I think needs clarification. I know plenty of strokers out there in S30's that run in the low 30's as daily drivers. Compared to anywhere from 20 to high 20's before modifications. My 260 gets 27mpg, I don't think that says "I don't care about mileage"... so I'm really trying to get what you're asking?

[Tony D]

OR.....

 

do you mean, elapsed miles on the vehicle? To which I would answer: I bought the donor car with 225,000 miles on it, and installed the engine. I have since put 110,000 miles on the engine with no issues.

 

I know plenty of people with 475,000 miles on their original engines.

 

I also know people who blew their engines up the first year. HOW you accrue miles is almost as important as how many. Again, what are you getting at with the curious nebulosity of your question???

[PLATA]

I get 30 MPG  on my LS1/ 6 spd  Z with regular gas 

[spiff]

No, it's a hobby vehicle. It is what it is. But I still swapped in a 5spd to get some more comfort on highway driving and as a positive side effect I get better mileage. If I want. But I often drive my car like I stole it so...

[zack_280]

I think the OP means miles on the odometer, but either way I don't think it's much of a factor.

[Slowpoke]

If your asking the question, I would say no. For "you" it does not seem to matter.

[Phantom]

I get 30 MPG  on my LS1/ 6 spd  Z with regular gas 

You're kidding?

1. How do you run regular gas on a 10.5:1 compression engine and not ping like crazy at low RPM?  That ignition system must dial the timing way back.

2. Best I've ever gotten out of my LS1/T-56 on the highway was 24.  What is your gearing?  Do you have headlight covers?  Anything else to improve aerodynamics.

[ktm]

You're kidding?

1. How do you run regular gas on a 10.5:1 compression engine and not ping like crazy at low RPM?  That ignition system must dial the timing way back.

2. Best I've ever gotten out of my LS1/T-56 on the highway was 24.  What is your gearing?  Do you have headlight covers?  Anything else to improve aerodynamics.

 

This.  I routinely average 20 mpg in my car with 3.70 gearing and an A4 transmission with tires 1 inch taller than stock.

 

I should get about the same fuel economy given that 4th gear is at 0.696.

[PLATA]

You're kidding?

1. How do you run regular gas on a 10.5:1 compression engine and not ping like crazy at low RPM?  That ignition system must dial the timing way back.

2. Best I've ever gotten out of my LS1/T-56 on the highway was 24.  What is your gearing?  Do you have headlight covers?  Anything else to improve aerodynamics.

That is the # for highway driving on 6th gear at 17,000 rpm @70 mph  with the A/C on, my diff a Q45 unit , she runs fine on BP regular gas.  As far as aerodynamics she is always waxed 

Edited March 20, 2014 by PLATA

[RebekahsZ]

Odometer mileage doesn't matter. Rust is what matters. IF you ever find two Z cars with equally perfect bodies, get the one with lower mileage. Fatigue cycles do matter on these old brittle cars. But rust trumps miles.

 

Gas mileage. What is that? I use my z for limited driving, mostly at wide open throttle. I'd rather run a little rich and avoid burning a piston. I show up at the track with a full tank and it's close to empty when I leave. Fast cars driven hard burn a lotta gas.

[Phantom]

All - I just don't get it. My LS1 has 38,000 miles on it.  Running through a T56 and a 3.70:1 R200 LSD and 225/50-16 tires.  Car gets about 16-17 around town and best it's done on the highway at 70 is 24 MPG.  That's running in 6th at 1,750 RPM across Texas.  Did have the AC on so that may account for the extra 4 MPG?  Then again - maybe I should start running 87 octane instead of 92 and see if the fuel economy goes up?  Maybe I should have it dyne tuned and see if I'm running a bit richer than it needs to be.  The exhaust doesn't look particularly black (more gray)so it can't be too rich.

RebekahsZ - I know what you mean about gas mileage, though.  I actually tracked mine when I was racing at Texas Motor Speedway and the car averaged 10 MPG.  Considering that was rocking back and forth from maximum braking to WOT for two hours and speeds up to 130 MPH I thought that was pretty good.

[RebekahsZ]

I'm up late with insomnia from cold medicine. Phantom-why do you care what your mileage is? Do you drive a V8 powered 40- year old car to save money? When gas is $3.50 a gallon? If so, get a Prius (or Miata😉) to commute in and drive your Z for special occasions. Or just acknowledge that you are driving a hot rod. I guess there are many reasons to spend $500 on a dyno session. But of it drives well, the plugs are tan and it doesn't stink, you are probably fine. I'm not knocking you. I use a V6 S10 as my tow vehicle and it is really too small for the job. But it weighs 4,000# and I really have a hard time going out and spending $40,000 to have a full size truck that weighs 6,000-8,000# and won't fit in my garage. Now, when I get good and tired of my front and rear main seal leaking, I'm really thinking of putting an LS2 in my truck. That should handle the towing, but the real problem is not the go-ing but rather the stop-ing. And I'm curious to see if it improves my mileage, haha. Maybe then I can justify it to Mrs Thompson, who accurately accuses me of pouring money down the drain.

[Edward]

I apologize for not clarifying, but yes i mean miles on the speedo. i wouldn't own z If it where for fuel economy haha

[Glliw]

MIleage doesn't matter too much as a lot of the time the damage that matters on these cars is more related to time and environment, not operational distance (rust).  That, and after 35+ years, who knows if the speedometer has taken a lap?  Mine says 63k miles on it and it looks to have that amount of wear and tear across the board but...maybe it got lapped to 163k? Without exact historical data on when maintenances were performed, you never know.

[PLATA]

They are four decades old cars , what matters is body integrity . 

[Tony D]

I apologize for not clarifying, but yes i mean miles on the speedo. i wouldn't own z If it where for fuel economy haha

Thank you!

[Phantom]

I'm up late with insomnia from cold medicine. Phantom-why do you care what your mileage is? Do you drive a V8 powered 40- year old car to save money? When gas is $3.50 a gallon? If so, get a Prius (or Miata😉) to commute in and drive your Z for special occasions. Or just acknowledge that you are driving a hot rod. I guess there are many reasons to spend $500 on a dyno session. But of it drives well, the plugs are tan and it doesn't stink, you are probably fine. I'm not knocking you. I use a V6 S10 as my tow vehicle and it is really too small for the job. But it weighs 4,000# and I really have a hard time going out and spending $40,000 to have a full size truck that weighs 6,000-8,000# and won't fit in my garage. Now, when I get good and tired of my front and rear main seal leaking, I'm really thinking of putting an LS2 in my truck. That should handle the towing, but the real problem is not the go-ing but rather the stop-ing. And I'm curious to see if it improves my mileage, haha. Maybe then I can justify it to Mrs Thompson, who accurately accuses me of pouring money down the drain.

My concern over mileage is when someone with a comparably equipped car is doing 25% better. I'd have the same question if it was 12 & 15 MPG. If the mileage is that much better then somehow the combustion is more efficient which, in my tiny little mind, says that there is more power available in that engine over mine or the body has a much lower Cd which could equate to better ET's. Just searching to see what I may have overlooked.

 

Edward - O apologize for hijacking your thread -shame on me. FWIW - I agree with everyone else that total miles on the car is not nearly as important as a high integrity body. I was fortunate to get one that was almost completely rust free. It now has 238,000 miles on it and is going strong - the body that is - the rest of the car has all been replaced.