Only getting 6.5 mpg w my 383 Stroker
05-13-2012, 11:32 AM
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Only getting 6.5 mpg w my 383 Stroker I know the more power you have the less mpg, but this seems extremely low for a vehicle producing 404 rwhp.
05-13-2012, 11:54 AM
#2
Running that rich can wash down cylinder walls and dilute your motor oil, wiping the bearings and ruining your engine.
05-13-2012, 01:45 PM
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I will try one more time to get the mail order tune looked at by the original tuner. If no luck with them, I will park it and save money for Dyno tune.
Was thinking I might want to change plugs and O2's since I ran on them for a while with a bad opti and see if mpg improves.
Was thinking I might want to change plugs and O2's since I ran on them for a while with a bad opti and see if mpg improves.
05-14-2012, 08:58 AM
#6
Ouch! Don't feel too bad...my new 383 build gets 11 mpg and my old cam only setup got about 12mpg (both had mail order tunes). There is light at the end of the tunnel as dyno tuning picked up mileage significantly (16mpg) on the cam only motor and I expect the same with my new setup when it gets dyno tuned. I would check the readings on coolant temp sensor to make sure it is accurate too; and your plugs may be fouled making the issue worse.
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05-14-2012, 07:19 PM
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I got horrible mileage on my mail order tune for my previous 383, just my silly butt optimizing things gained me 5 MPG avg!!. My new motor is getting 18 on the highway and it seems I can watch the gage move around town..lol (not really). But I average 12 -13 depending on my foot.
05-14-2012, 07:40 PM
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That fuel mileage is turrible. I get 12/17 with mine. Don't drive it until you can get that straightened out. 400rwhp usually equates to low to mid 20's depending on terrain, curb weight and a whole slew of other things. May yield more power once a correct tune is applied.
05-15-2012, 08:06 PM
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My 396 in a 3750 lb car will barely get 14 on the highway doing 80 with the converter locked. City is 8-10, but its got a 4000 stall lol. Tune is very good.
05-16-2012, 07:28 AM
#14
6mpg is horrific for that motor........thats about what i get in town if i take mine for a ride with about another 200hp on tap a 4800 stall and 4.56's lol...........my xfi reads about 11mpg on the highway with mine locked up in OD...sounds like your tune needs some serious help
