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Ok - I KNOW that gas mileage is not the reason that you all build/buy these cars - but I am interested......looking for 1 more reason to convince myself I need one of these cars..........seems a few posts have mentioned 25+ on the hwy......but I would like to broader sample:


Post what kind of gas mileage you get in your GTM:


Engine:
Transmission:
Gas Mileage city/hwy:


Thanks.
 

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Yeah, maybe that is a bit like asking, "Is it $4 or $5 to touch the hand of God?" :001_rolleyes:
 

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Seems fair

i would also like to know. although it doesn't change the fact that i WILL own a gtm. it might help in deciding what engine to acquire. cus in Oklahoma its still going to be the fastest thing on the road bar the one or two atoms zipping around. so gas mileage would be some welcome info. plus this could be added to the GTM wiki. so its a twofold win lol. help some newbs and contribute to the effort of stopping newbs from asking erroneous questions. :p
 

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Apparently not an irrelevent question, as I have plenty of prospective buyers ask or are concerned with MPG. Unfortunatly for me, I don't know if I would/could ever find out if I owned one.......I imagine I would have the same problem finding out max MPG in a GTM as I do in my Mazda3. The only reason I know my Mazda is capable of 34mpg is from being forced to follow some slower traffic for about 50 miles. Normally I average a lot closer to 26.
 

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Great question, however there are too many variables.

You'd need to add items to your list like; shoe size, calf strength, foot velocity, percentage of lead :001_smile: and so on......Unlike a production car where the manufacture will conduct the test in a controlled environment.

You could use the numbers of the differently equipped corvettes, add a few miles for the extra weight and have a set of numbers that are just as useful.
 

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http://www.ffcars.com/forums/42-factory-five-gtm-forum/261414-gas-mileage.html
So I drove 474 miles round trip to the Turkey Run in Daytona. I used 18.3 gallons of gas. I was running 80+ except around Orlando which is always a parking lot, got stuck in traffic for almost an hour just outside the track. I have an LS1 with 410rwhp so I'm thinking 25.9 miles per gallon is pretty good.
Keith
I have a pure stock LS6 and a pure stock G50-50. I was reving 2500 rpm at 72 mph and I averaged 22.66 mpg. For these longer drives, I wear ear plugs. I think that it really cuts down on fatigue. It's funny, that at the end of one of these long drives, I'll remove the ear plugs about a mile from home and the change in noise makes me think that my exhaust must have fallen off completely during the drive home. I have factory exhaust manifolds, the FFR exhaust piping plus custom 11" long turbo mufflers from Stainless Works. I think that it would be quieter if I was crusing at 1800 rpm instead of 2500 rpm (not to mention the how this would also help my mpg).
mdowns
 

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Make sure you get taller high gearing put in your transaxle so you can take advantage of the good gas mileage capability of the LS motors. They shine by running super low RPM on the highway, which will not happen with stock Porsche 5th or 6th gear and even in my opinion with the Mendeola gearing (if you choose to wait for one of those...) The Porsches happy RPM range is much higher and they don't have the torque to chug along at the nice low RPM of an LS motor. This is why the Porsche trans is not ideal for an LS motor if you keep stock gearing (at least on a street car).

I was also concerned with mileage so my trans has a taller 5th gear installed (G50-03 LSD) to help. It is still not quite as low as 6th in a vette, but much closer.

My commute to work is 100 miles a day, so on those days I want to bring the GTM, getting decent mileage will be a nice bonus On the interstate. Controlling the lead foot is not really a problem, everyone is already going 10MPH over the limit anyway. Around town playing is whole different story :)
 

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B,
That's cool that you used Keith's post from his trip to the Turkey Rod Run last year. If my car is done we may do a dual GTM cruise up to Daytona this year. Wish me luck.:thumbup:

Make sure you get taller high gearing put in your transaxle so you can take advantage of the good gas mileage capability of the LS motors. They shine by running super low RPM on the highway, which will not happen with stock Porsche 5th or 6th gear and even in my opinion with the Mendeola gearing (if you choose to wait for one of those...) The Porsches happy RPM range is much higher and they don't have the torque to chug along at the nice low RPM of an LS motor. This is why the Porsche trans is not ideal for an LS motor if you keep stock gearing (at least on a street car).

I was also concerned with mileage so my trans has a taller 5th gear installed (G50-03 LSD) to help. It is still not quite as low as 6th in a vette, but much closer.

My commute to work is 100 miles a day, so on those days I want to bring the GTM, getting decent mileage will be a nice bonus On the interstate. Controlling the lead foot is not really a problem, everyone is already going 10MPH over the limit anyway. Around town playing is whole different story :)
J,
Great point on the gearing. I had Stan put a taller 6th in my box. I can cruise at 70mph at about 2050 rpm. My only regret is that I did not have him redo the entire box to better match the LS6's power band. Check out the chart.
 

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My '02 z06 before I supercharged it would get 33-34 on the highway. That was a LS6 with basic bolt-ons, and of course, 6th gear. Having comparable gearing in the GTM with the LS6 should yield similar results I'd think.

In the GTM (408 LS2, no 6th gear) I'm averaging around 20mpg, and most of my driving is on country backroads. ie: heavy foot and lots of fun.
 

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most of my driving is on country backroads. ie: heavy foot and lots of fun.
S,
I'm so jealous. Since putting the body on the chassis the only thing I want is for my GTM to be on the road.

At least I could Kart (I called it testing:w00t:) before I put the body on.
 

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My '02 z06 before I supercharged it would get 33-34 on the highway. That was a LS6 with basic bolt-ons, and of course, 6th gear. Having comparable gearing in the GTM with the LS6 should yield similar results I'd think.

In the GTM (408 LS2, no 6th gear) I'm averaging around 20mpg, and most of my driving is on country backroads. ie: heavy foot and lots of fun.
Stock 5th Gear?
 

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I get 10 to 15 MPG but 600rwhp I think is good. I know a top fuel dragster is alot worse than what I have. Also stopping at alot of gas stations gives you a break from driving and you get your picture taken more.
 

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i just checked my car today. im getting 12 miles to the gallon. 550 hp, ls1. Of course I was doing double the speed limit and 6,000 rpm shifts :) MAybe when I do a long road trip on the interstate i will do it again.

Don
 
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