What's your MPG?

by **jeff's93astro** » October 7th 2009, 4:38am

both have 255/70/r15

by **astroturf** » October 7th 2009, 4:45am

jeff's87astro wrote:both have 255/70/r15

Yup bigger than stock. Have you corrected the speedo for this? Jim

by **jeff's93astro** » October 7th 2009, 4:48am

no when i put the tires on it i did a test run with a GPS and its dead on

by **astroturf** » October 7th 2009, 4:55am

jeff's87astro wrote:no when i put the tires on it i did a test run with a GPS and its dead on

Stock size for that model was 215/75 15 with a diameter of 27.7 inches, new tires are 255/60 15 with a diameter of 29.1 inches. Unless you have altered something to compensate for that change then: When speedometer reads 60mph (96.6km/h) actual speed will be 63.1mph (101.6km/h): 5.2% faster. Which means you're traveling further than your speedo says, hence your getting better mpg than you think. Jim

by **jeff's93astro** » October 7th 2009, 5:03am

i dont know if it was off before the tire change because the original owner parked it for six years so i never got it over 35mph before i changed the tires since they where dry rottted

by **jeff's93astro** » October 7th 2009, 5:24am

just went out to my van and checked the sticker on the door the factory tire size for it is 205/75/r15

by **astroturf** » October 7th 2009, 5:31am

jeff's87astro wrote:just went out to my van and checked the sticker on the door the factory tire size for it is 205/75/r15

That makes it a much bigger change then. When speedometer reads 60mph (96.6km/h) actual speed will be 64.4mph (103.7km/h): 7.3% faster.
If you factor in the new figures, your actual/real time mpg isn't bad at all. Jim

by **jeff's93astro** » October 7th 2009, 5:55am

lets say i'm getting 15 then how do i figure + 7.3% to that

by **astroturf** » October 7th 2009, 6:07am

jeff's87astro wrote:lets say i'm getting 15 then how do i figure + 7.3% to that

Yes, Jim

by **jeff's93astro** » October 7th 2009, 6:11am

i came up with 16.095mpg but that still dont seem much better?

by **astroturf** » October 7th 2009, 6:19am

jeff's87astro wrote:i came up with 16.095mpg but that still dont seem much better?

Well you are pushing a much heavier tire. As could be seen in the small increase of 7.3% due to tire diameter, there could be a further increase based on tire rolling resistance. But, hey they do look good on that van. So enjoy it, Jim

by **jeff's93astro** » October 7th 2009, 6:29am

i'm thinking about going down to 235/75/r15 but thank you for the help

by **astroturf** » October 7th 2009, 6:36am

jeff's87astro wrote:i'm thinking about going down to 235/75/r15 but thank you for the help

Check out this link. Maybe it'll help in your tire size decision.
http://www.wheelsmaster.com/rt_specs.jsp
Jim

Recent Image Attachments
What have you done with your oth... Attached by: icebrrg3rd in Uncategorized Views: 175476 Comments: 3000 Date: Feb 23 '21 Time: 6:27pm » Read last comment
What have you done to/with your ... Attached by: Mmusicman in Uncategorized Views: 801657 Comments: 16420 Date: Feb 16 '21 Time: 8:08pm » Read last comment
Enjoying Outdoors with Astro/Saf... Attached by: Coronavan in Uncategorized Views: 37287 Comments: 235 Date: Feb 14 '21 Time: 4:06am » Read last comment
1999 AWD Astro 103k for $5,500 -... Attached by: Upstatevanvibes in Uncategorized Views: 159 Comments: 8 Date: Feb 14 '21 Time: 3:20am » Read last comment
How's Your Mileage ? Attached by: Coronavan in Uncategorized Views: 239 Comments: 5 Date: Feb 14 '21 Time: 1:18am » Read last comment

What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Re: What's your MPG?

Who is online

Uncategorized Forum
An all-purpose area for Astro/Safari van related discussion. These forums typically contain van-related but ill-assorted topics unfit for any other category. General questions and information relating to Astro and Safari Vans only.
Moderators: Leeann_93, icebrrg3rd
Post a new topic To create a new topic in Uncategorized, click this button:
Previous topic Next topic