Power Curve and Gear Ratio

[magik235]

Where can I find a power curve chart for a stock 1985 350? I have searched with no luck. I am looking for the basic horsepower / torque / rpm chart.

 

[magik235]

I am trying to determine what rpm maximizes fuel economy in an RV.

 

[76zimmer]

I think an engine is most efficient at max torque, but most fuel efficient at the lowest rpm that will get the job done without lugging the engine.

 

[plyr2k]

I am trying to determine what rpm maximizes fuel economy in an RV.

Every engine is max efficient at max torque. that engines max torque should be at about 2200rpm

 

[76zimmer]

I would guess that a mid 80;s 350 would be in the 3200 max torque? 2200 seems kinda low even for a smog 350.

 

[blazinzuk]

buy a vacuum gauge. This alone will not determine your best cruise but it can assist in helping you pick an rpm at which your efficiency will be best.

Couldn't find any numbers for ya but I bet Zim is pretty close on torque figures and rpms

 

[magik235]

Do either of these number sets look right for a K30 with a 350? I have searched the web for hours and can not find solid horsepower and torque numbers with the associated rpm.

185 HP @ 4000 rpm
280 ft/lbs torque @ 2400 rpm

160 Hp @3800 RPM
260 ft-lb torque @ 2800 RPM

 

[magik235]

Based on the input above and the numbers below, should I target 2400 rpms at 60 mph for my gearing to maximize fuel economy?

185 HP @ 4000 rpm
280 ft/lbs torque @ 2400 rpm

160 Hp @3800 RPM
260 ft-lb torque @ 2800 RPM

 

[sweetk30]

buy a vacuum gauge. This alone will not determine your best cruise but it can assist in helping you pick an rpm at which your efficiency will be best.

http://www.autometer.com/cat_gaugedetail.aspx?gid=2479&sid=1 simple and effective keep it as close to green as possible.

i installed 1 in my old truck and within 2 tanks of gas i was gtting better fuel mileage on a tank by watching what a tiny bit of throttle diffrence made in vac. i relearned how to drive by the vac gauge for better fuel economy.

also that big motor home get this also to keep a eye on tranny temps. http://www.bmracing.com/PRODUCTS/Cooler-Accessories/Transmission-temperature-gauge-kit

here is how i just did mine in my plow truck.

 

[Bent77]

On several 350 trucks I have had, found my best mileage between 2400-2600. the fact you are pushing a brick wont help anything, but after 62 mph, aerodynamics start to play a hugh factor.

 

[chulisohombre]

2200 to 2400 rpm is the best fuel economy on a small block.they like to run best in that range.highest torque usually around 4000 rpm on most of them as well.i dont like to run mine above 3 g to help keep it lasting longer and get better milage.vaccuum guage will help a lot to keep at max efficiency.14.2 is optimum i believe,but no engine will reach that mark.getting it as close to that as posible will net the best mileage.