Editing Openai/695c4a9d-28a0-800d-9f93-cab63ec35c09 (section)

=== Assistant: Perfect — that usage pattern actually makes the decision very clear. ===
Perfect — that usage pattern actually makes the decision very clear.

With street driving 1–2 times per month and track once a month, here’s the straight, experience-based answer for your car.

==== ### ====

It gives you:
* Better track performance than 4.10
* Noticeably better street manners
* No downside with your converter or torque curve

This isn’t a compromise gear — it’s a correction.

==== ### ====

With 28" tire + TH400:

|     |     |     |
| --- | --- | --- |
|     |     |     |
|     |     |     |

That means:
* Less noise
* Less heat
* Less converter slip
* Less “busy” feeling

===== Right now: =====
* Light throttle = RPM jumps quick
* Heavy throttle = violent flash

With 3.73:
* Throttle feels more linear
* Car hooks more predictably
* Easier on drag radials on the street

==== ### ====
* Might lose .01–.02
* Might not change at all

Your torque + loose converter covers this.

===== This is the win: =====
* MPH goes up
* ET stays the same or improves

Expected improvement:
* +2 mph
* −.10 to −.15 ET

That’s a real gain, not tuning noise.

===== - Drops from ~6,000 → ~5,500 =====
* Engine happier
* Less stress
* More usable power

==== 3.55 would: ====
* Be great for highway driving
* Still work at the track

But…
* You’d start to give up 60-ft consistency
* Converter may feel slightly lazier on launch
* You’d need more launch RPM tuning

Since you don’t drive it much on the street:
👉 3.73 is the better all-around match.

==== For your: ====
* Big torque Buick
* Loose converter
* TH400
* 28" tire
* Light street use, monthly track use

✅ Swap to 3.73 gears
✅ Manually shift at ~5,600–5,800
✅ Keep drag radials

You’ll get:
* Faster slips
* Better MPH
* Calmer RPM behavior
* A car that feels more “connected”

If you want, next I can:
* Help you decide pinion angle / suspension tweaks after the gear change
* Give you a first-pass checklist after swapping gears
* Estimate converter heat reduction and cooling needs

Just tell me what you want to tackle next.