LS1 milage from an L98

[tdr1919]

I have a stock 86 (manual) coupe, I would like to get the mid 20 mpg that the later C5's are getting. can this be achieved with modifications to my L98?
(I do not care about horse power increases)
Thanks,
Tom

 

[Edmond]

You could get better mileage by simply keeping the car well maintained such as proper tire pressure, regular oil changes with a good synthetic oil (5w-30 seems to be a popular choice), plugs, wires, air filter, etc...

A better flowing exhaust system would also reduce backpressure and get you better mileage. Of course, this is assuming that your driving habits are the same.

 

[tcolyer]

I have an 86 manual 4+3 looks just almost identical to yours. I have put a free flow exhaust (true duals no cats at all), a K&N filter, opened the filter cover, TB spacer, keep it well tuned and I get 25 - 26mpg at 65mph above 75mph it goes down slightly. I do not have to babie it to get this mileage.

Hope this helps

 

[stang-etr96]

My 91 L98 and 96 LT4 both get 27 mpg on the highway. Only mods to both are exhaust and K&N air filters. You should be getting the same as long as your rear gears are stock and the car is in good tune.

 

[rrubel]

I agree with the other posts. Even with 135k miles on my 86 4+3, I'd get 25-26 MPG on the hwy. During the 93 Corvette Caravan, my 1700+ mile trip that included highway cruising, sitting in traffic, some light fun and games, and lots of slow crawling netted me over 24 mpg. The secret (and the really HARD thing) is keeping the right foot up.
[RICHR]

 

[rad928music]

you should be able to get more than 20 on the highway easy.

 

[CTYANK2]

Never could get my 1989 L98 past 20mpg on the highway even after all the usual stuff was replaced & tuned. (injectors, wires, plugs, fuel filter, sensors, etc.) I have TPIS headers, open air lid and basically stock other than that.

Oh, 3:07 gears.

 

[Radar]

My basically stock 89 L98 gets 26 to 27 on the highway.

Radar

 

[ZumZum]

My '88 A4 with the 2:59 rear gear averages between 20 & 21 mpg. I usually get about 27-28 on the highway with a one-time best of 31 (must of had a good tail wind that day).

 

[Bonnell]

My '88 A4 got 30.1 MPG on the highway at a steady 70. That was on an engine with 160K + miles. The first time I hit that I found that the display firmware had a glitch. The MPG went from 29.9 to 3.01.

The only mod on the car was headers.

I would think you could get a lot better.

 

[jester]

My stock '88 gets 20 in local driving and 26-27 at freeway speeds. When we did our Route 66 trip I got 24 mpg for the entire 5200 mile trip. Of my three cars, the Vette gets the best mileage, IF I drive it like I do the other cars.

 

[rrubel]

This reminds me of an interesting comparison that AutoWeek or Automobile did last year where they took a Prius (hybrid), a Corvette (gas), and a Jetta (diesel) on a long roadtrip. The Jetta did best, but IIRC the Vette beat the Prius - one reason they gave being that they never had to slow down for turns so they never had to use gas accelerating

[RICHR]

 

[CTYANK2]

This reminds me of an interesting comparison that AutoWeek or Automobile did last year where they took a Prius (hybrid), a Corvette (gas), and a Jetta (diesel) on a long roadtrip. The Jetta did best, but IIRC the Vette beat the Prius - one reason they gave being that they never had to slow down for turns so they never had to use gas accelerating

[RICHR]

Does anyone have a link to that article?

 

[milehigreg]

Anyone?

I would LOVE to have that article to wave at my treehugger dirtworshipper coworkers. :bash

 

[Toms007]

I would LOVE to have that article to wave at my treehugger dirtworshipper coworkers. :bash

Greg, surely there aren't any of those out there in Colorado...........

 

[CTYANK2]

This must be the article:

http://www.autoweek.com/apps/pbcs.dll/article?AID=/20060424/FREE/60417021&SearchID=73244466514443

 

[rrubel]

Ok, that's indeed the article. Looks like I didn't quite remember it right, and I also don't recall the print version having the Accord in there. But still... that's really good mileage out of the Vette.
[RICHR]