-- Edited by Back in Black on Monday 15th of July 2013 03:34:59 PM
John D said
Jul 15, 2013
On the way to Powercruise this year I rolled 10,000 miles on "Blackie" since I bought him in October of 2008! Added 621 miles this weekend (on 26 gallons of gas BTW - that's nearly 24 mpg including over a dozen laps on BIR guys!!)
I think 10k miles on a car driven about 40 days a year is pretty
John D said
Jul 15, 2013
I didn't believe it either... but the speedo cross-checks against the GPS within 1 mph - I thought the gas gauge was busted, it didn't hardly move - but on refills the pump kicked off at about when it should have in respect to what the gauge said...
This engine/trans combo in the 2-1/2 ton Roadie would consistantly pull 24/25 mpg @ 65mph... with 2.56 gears. But lugging around 1500 less weight pushing an aero-brick with 3.08's at the same speed...?
I don't get it either, but the receipts & numbers don't lie. Gotta love 'puter controlled EFI
Derek69SS said
Jul 15, 2013
I was getting 24mpg with my LT1 with 3.08s too... dropped to 21mpg when I swapped in 4.10s
Chris R said
Jul 16, 2013
I wish I could say im supprised but ive talked to a few customers back in the 90's that had Impala SS's and one old boss of mine that had a mid 90's Roadmaster sedan. All these guys were saying they were getting mid to low 20's in mileage, yet I cant get even close to that ballpark with my Tahoe of the same era which always frustrated me, best I could get was something like 18MPG. I never really understood why GM didnt look into MPFI for thier line of trucks to get that same mileage, GM's best selling line of vehicles were thier trucks back then.
I know the TPI system that the F body had, had limitations, but there was technology to build on there. A little ECM tuning and perhaps a different intake design to get the low end torque up there (were trucks really need it) would have been a good start. IMO, TBI was outdated technology by the mid 90's. Full size GM trucks didnt get independent injectors until the LS motors came out, and even then, the gas mileage didnt improve much. I dont know for sure but I dont think there is much of a weight difference in a LT1 car like the Caprice/Impala SS/Roadmaster compared to something like an ECSB pickup so I dont know if weight difference would have been a factor. I could be wrong but IMO, it was all about the induction and ECM tuning that was a factor.
Lost in the 60s said
Jul 16, 2013
You're averaging 2k miles a year. I doubt I get that many on all mine combined.
The guy I bought my '38 from put 23k on it in the time he claimed it was drivable ~5 yrs~. He said he drove it all over during summer.
SShink said
Jul 16, 2013
That's cool John.
I usually average 2500-3000 miles per summer/fall with our Chevelle(s). It was killing me this season not to drive one until just last week, so now with almost 400 miles on it in less than a week, I've got some catching up to do!
Nice.

I think you have a generous ODO. 24mpg??? C'mon!
-- Edited by Back in Black on Monday 15th of July 2013 03:34:59 PM
On the way to Powercruise this year I rolled 10,000 miles on "Blackie" since I bought him in October of 2008! Added 621 miles this weekend (on 26 gallons of gas BTW - that's nearly 24 mpg including over a dozen laps on BIR guys!!)
I think 10k miles on a car driven about 40 days a year is pretty
I didn't believe it either... but the speedo cross-checks against the GPS within 1 mph - I thought the gas gauge was busted, it didn't hardly move - but on refills the pump kicked off at about when it should have in respect to what the gauge said...
This engine/trans combo in the 2-1/2 ton Roadie would consistantly pull 24/25 mpg @ 65mph... with 2.56 gears.
But lugging around 1500 less weight pushing an aero-brick with 3.08's at the same speed...?
I don't get it either, but the receipts & numbers don't lie. Gotta love 'puter controlled EFI
I wish I could say im supprised but ive talked to a few customers back in the 90's that had Impala SS's and one old boss of mine that had a mid 90's Roadmaster sedan. All these guys were saying they were getting mid to low 20's in mileage, yet I cant get even close to that ballpark with my Tahoe of the same era which always frustrated me, best I could get was something like 18MPG. I never really understood why GM didnt look into MPFI for thier line of trucks to get that same mileage, GM's best selling line of vehicles were thier trucks back then.
I know the TPI system that the F body had, had limitations, but there was technology to build on there. A little ECM tuning and perhaps a different intake design to get the low end torque up there (were trucks really need it) would have been a good start. IMO, TBI was outdated technology by the mid 90's. Full size GM trucks didnt get independent injectors until the LS motors came out, and even then, the gas mileage didnt improve much. I dont know for sure but I dont think there is much of a weight difference in a LT1 car like the Caprice/Impala SS/Roadmaster compared to something like an ECSB pickup so I dont know if weight difference would have been a factor. I could be wrong but IMO, it was all about the induction and ECM tuning that was a factor.
The guy I bought my '38 from put 23k on it in the time he claimed it was drivable ~5 yrs~. He said he drove it all over during summer.
That's cool John.
I usually average 2500-3000 miles per summer/fall with our Chevelle(s). It was killing me this season not to drive one until just last week, so now with almost 400 miles on it in less than a week, I've got some catching up to do!