Thread: Opinions..

Tweet

Whats a acceptable 65 mph rpm on a chevy small block?
This is for performance and a 60 mile one way trip is going to be considered a massive journey.Mostly in town and maybe 10 to 15 mins max highway mixed in.
From what I have read ,it seems the best performane rpm at cruise {or 65 mph for me} is going to be a rear gear that puts it right at max torque rpm.For me thats 3500 rpm at 65 mph .In order to achieve this rpm at 65,current 3.73 gear would require a 24 inch tall tire or a 30 inch tire with a 4.88.I was thinking about 26 to 30 inch tires for the back and 26 to 28 for the front.
I am flexable on tire size for the rear and front.
http://www.wallaceracing.com/calcrgr.php
This is a continuation of my other thread sorta...I am into the rear end and going to go ahead and change the ring and pinion while I am in there.The specs on the motor are 3500 rpm max torque 356 and 5500 rpm max hp 290.....I am also running a 3 speed manual trans and this is for my 66 chevy truck at approx 3500lbs.

Heres my opinion on it ,This will be for fun as I have other transportation to use every day,no actuall truck duties will be performed with it and I built it to have fun.....My idea of fun is to be able to quickly accelerate and I like feel of the pull of a motor.Gas is no concern as I will drive as I can afford it ,economy is no concern and being able to go 300 miles away is of no concern........4.11 seems to be a happy medium...but it is a compromise of gas mileage and performance which tells me it does neither of those well.They would be a compromise ,well I am willing to compromise biased to the performance side,I just do not want to get too crazy with it where top speed is 90 mph at 5500. 100 mph in the 1/4 is all this would probably do on a good day soo that would be plenty,considering its going to see the track one time in its life at the most. I also notice the ratio determins price.....theres a set of 4.56s alot cheaper than the lower or higher sets.. possible upgrades in the future are a 5 or 6 speed trans or a 700r4...engine will remain the same untill it blows.Ohh and if makes any difference there will be no launches and its a open differential for now..