any of you running a 350/ turbo350 with a highway gear in there hot rod? getting ready to put a new 350/290 in my hot rod i have a turbo 350 in it now with a 2.79 gear wondering how the gas mileage would be? i got an old 283 2bbl in it now get sometimes about 20 mph now. getting ready to head west this summer, dont really want to change to an overdrive but might have too. any thoughts?
10-25mpg too many factors including tuning come into play. run it and have fun, but dont expect 30mpg
chevy 350/ with a turbo 350? you can not find a cheaper, more durable, more easily repaired, adaptable, spare parts availability combo around.
Should be just fine although pretty slow out of the lights, which would personally drive ME nuts. It isn't my car though, right? The real advantage of an over drive trans is always thought of as being the overdrive... A better advantage is the fact that most of them come with a much deeper first gear so you can accelerate from the stop lights on less throttle posistion. You do have to change you rear gears around to compliment the trans though, remember, it's all a SYSTEM.
I had a 327/300 , 450 - 4 barrel Holly with a turbo 350 and a 3:73 in the rear and got well over 25 mpg. 1845 lbs.. JMHO P.S. economizer cam . I forget grind ?
If you tune and your engine will pull at low RPM you should be able to stay in the 20 MPG range. Try this, go to this calculater and punch in the required numbers, if you don't have radio tires just punch on the tire diameter. Chose the T350 or any tranny with a 1:1 final ratio and see how many Rs you are pulling @ highway speed with your rear gear. now try and figure out if your engine is in th power band at that RPM or if it is below it and lugging. If you are lugging your engine your MPG will be crap, if you are at the top of your power band your MPG will be crap as well, but if you are right in the sweet spot you are golden. http://tri-5.chevyrides.com/rpm.php
Does that mean that you won't be driving the car SSMT? { that's Saturday, Sunday, Monday, Tuesday for those who started Happy Hour a little early today }.
Actually, if you take out the 2.79 rear gear and install something like a 3.25 gear, your mileage could improve with that 283/2brl. These little motors are more efficient at 2500 rpms and up...puts it in its sweet spot...my .02 cents.
We went from a 2.79 gear to a 4.11 gear in the Ravens roadster and with the .7 final drive and my engine it improved his mileage about 10 galllons over a 4.5 hour trip. The OPs 280 HP 350 should live well at low RPM but probably not at idle, he is going to want to be turning in the low to mid twos at least.
Ok here we go. National gas average for regular is per $3.32gal and its 2194 miles from Dayton, Ohio to Los Angeles, Ca and is pretty much a 2 day trip. If you get 20MPG it will cost you $364.20 and if you get 15MPG it will cost you $485.61 for a difference of $121.41 or round trip of $242.82. I am assuming you are going on vacation or to a automotive event, with your bare bones high boy radial tires hot rod, so you will have food, hotel, souvenirs, shopping, site seeing expenses? Correct? With that being said does the difference between 15mpg and 20mpg really matter? Drive 65mph and not 80mph that should save you a buck or 2. When did we start caring about what gas mileage our hot rod gets? Maybe you should find a wrecked Prius and do a Hyrid swap? Sorry maybe I'm just having a bad day, but wouldn't a it be a cooler thread if it was "I raced across country in my High Boy and only got 12mpg, but I don't care because it was just so cool to drive across country in a High Boy."
My car is a i931 model a, 350, @ bbl holley, powerglide, 285-70-15s, ... 4" channel, no chop highboy. All I get is 10- 12 mph @ 65 mph. Would like better but really dont know how.
When we did this as I have with my avatar to the tune of about 25,000 miles a year. Fuel milage is important if you want to drive your car distances everyday. I have spent tons of time and a bit of money optimizing my car so I didn't HAVE to drive a late model, anywhere. Optimizing it usually also pulls dividends in a better running, faster car too. Efficiancy is efficiancy.
Why is it whenever gas mileage comes up some guy "having a bad day" pops up with some Prius crap. It's a legit question. Hats off to he guys who are willing to help out.
I had a very similar set up in my 47 ford. I found it t be a poor combo around town( rpms too low) but once you were cruising at 50 or better it went well. probably the main reason I switched to the 200-4r.
Dudley, There some spots out on I 40 in Arizona where the difference between 15 mpg and 20 mpg means making the next fuel stop....or not....
Install a vacuum gauge and drive/gear/shift your car to get the highest vacuum reading, that will help with mileage... my '65 SS Impala (not a lightweight car) with 350 (.480 lift, I forget the duration) Offenhauser 360 w/ 650 holley, 305 heads, stock T350 and 3.08 gear gets like 16-18 mpg on the highway...
Just do your homework on money savings. Don't spend dollars to save dimes! Do the calculations. I have a guy at work that constantly tells me where the cheapest gas is to buy, (usually only .03cents cheaper per gal than where I normally buy it) only problem is that is it 7-8 miles out of my way, 14-18 miles on a round trip, hell my daily only gets 20mpg. WTF, ( couldn't resist) to save .03 cents on 15 gals computes to .45 cents. @ 3.17 per gallon it cost me damn near $2.72 to save .45 cents if I drive nearly 20 miles for 15 gals! WTF I say! I say do the math, if you aren't going to break even in a season of driving, ( insert the miles you drive your car per year) don't fix it cause it ain't broke! Fenderless
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