Gear choice

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come take a 5000 mile road trip in it with me and you'll see for yourself.
Seems like it would be way easier for both of us to just have you give a short description of what makes it better.

I am not trying to bust your balls, I genuinely don’t understand what could sound better,if the motor is healthy and in tune, between 1,000 rpm smack dab in the middle of the engine operating range.
 
the cars happy spot is around 65ish. just the way it is.. if you can't accept that i don't know what to tell you.
 
Do you have a 2nd car? I would go 3.55, let the engine breathe. In CA freeway driving most areas it's 65MPH and if no traffic, you better be driving 75-85 in the fast lane or you will piss a lot of people off so now you're in the slower lanes and you can cruise along at 65-70. other option what I did when younger & speed limit was 55 on freeway, I traded my 3.23 for 4.56 and still drove all over then I started my 8 3/4 collection of other 3rd members, it takes less than 1 hr. to swap gear sets, with a few choices if you want to go a long trip swap in some freeway gears you can still do it with the 8 1/4, will just take a little longer or swap in OD trans that you have.
 
I installed an overdrive to cruise 65=2240. Much quieter, smoother, relaxing.
Before od my car was cooking 65=2870 (manual trans) and had an annoying sound at 65, notta boom, just "impatient" The body just amplified whatever the exhaust was doing.
But at 65=2240, that is gone; thank God.
My engine sounds really good at 2800, so that is my preferred shiftpoint, and I make the shift lazily. This gets me 63mph, then into od, and lets cruise.
The point is that I have a choice.
If you are limited, then just know that your 5.9 will cruise either; but always go for the lower of two choices. The 5.9M has a generous amount of bottom end torque, so 3.21s would be my choice. Allbeit; I would likely stall it at 2800or so, and run a lock-up.
 
Thanks for the replies. The ax-15 swap won’t happen for a while, I was sort of kidding.

Leaning towards 3.55s because at this point I wouldn’t mind an around town ripper. I’m so tired of the 2.76s out back and my exhaust has very little drone above 2500 rpm.

My only concern at this point is overheating at 70mph with 3.55s. Maybe unlikely?
 
Thanks for the replies. The ax-15 swap won’t happen for a while, I was sort of kidding.

Leaning towards 3.55s because at this point I wouldn’t mind an around town ripper. I’m so tired of the 2.76s out back and my exhaust has very little drone above 2500 rpm.

My only concern at this point is overheating at 70mph with 3.55s. Maybe unlikely?
Figure out the highway rpm of the two gears sets at the mph you drive. Then go to some back roads drive in 2nd at those rpms for awhile see if your ok with the 3.55.
 
If I take my car to work it's 40 miles each way highway. I go 80 most of the way with 323/340/4 spd.( no overheating) Yeah she's revving high. If I kill it I have an excuse to do my 408/360 build lol.
 
That cam should easily let you do the 3.21 gear...but having gone through multiple gearsets here (over a number of years, but always behind a SB powered 727 drivetrain in the same car), I can say the following:

1) 2.94 - yikes...not good, for anything
2) 3.55 - what a 'day & night' difference that was, my ride was finally alive
3) 3.91 - aha, here we go: some business to do on the street
4) 4.10 - that's right, commit or go away (LOL)

These were all in the same chassis and tire sizes, 27.75" tall tire (275/65-15), I left out the converter and engine build details b/c I'm focusing on an overall assessment with the priority on the cruising 'feel'.

So yeah, that motor (408 W2 stroker) is pulling some RPMs at cruising speed (3700 @65), and with the header primary tubes sized at 1-7/8" and 3" X-pipe to the back, yup, she's a bit of a loud ride. But that is exactly what I wanted and besides, I only do about 3K miles a season on that thing.

Go 3.55s, I think you'll be happier!
 
For what it's worth my GM Gbody has 3.42 gears Turbo 400, 400 sbc base stroker, cruises nicely @55 mph and still ran 10.86 @125.5 n/a. Put the 3.23 in you'll be happy especially with a 26 in tall tire.
 
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