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

=== Assistant: Good question — and this is the right gear change to be asking about for your combo. ===
Good question — and this is the right gear change to be asking about for your combo. I’ll keep this specific to your car, not generic gear talk.

==== Switching from 4.10 → 3.73 will most likely: ====
* Increase MPH
* Keep ET the same or improve it
* Reduce RPM flare
* Make the car feel smoother and stronger through the lights

For a torque-heavy Buick + loose converter, this is usually a win, not a slowdown.

==== ### ====

With:
* 28" tire
* TH400 (1:1)
* Same converter

At ~99 mph (current):
* 4.10: ~6,000 rpm (with slip)
* 3.73: ~5,500–5,600 rpm (with slip)

👉 That puts you right in the sweet spot of your power curve instead of above it.

===== Taller gear = less load on the converter. =====

That means:
* Better coupling
* Less wasted RPM
* More power to the tires

This is why:

: 

Expect:
* +1.5 to +3 mph in the 1/8

===== You might lose: =====
* .01–.03 in 60-ft

But…
* Your current 1.47–1.49 is very strong
* Buick torque + loose converter will cover it

Often the 60-ft stays the same.

===== This is where 3.73s help most. =====

You’ll see:
* Stronger pull from 330–660
* Less “running out of gear” feeling
* Car keeps accelerating instead of flattening

This is exactly what your slips show you need.

==== ### ====
* 6.85 @ 99 mph

===== - 6.70–6.75 @ 101–102 mph =====

That’s not theory — that’s what torque cars do when over-geared.

==== - RPM won’t “jump” as violently ====
* Throttle will feel more connected
* Car will feel like it’s pulling longer
* More confidence staying in it

Most people say:

: 

==== (Does NOT apply to you) ====
* Very small engine
* Very tight converter
* Light car with high RPM power

You have the opposite of all three.

==== For your: ====
* 600 hp Buick
* TH400
* Loose converter
* 28" tire
* 1/8-mile focus

👉 3.73 is the smart gear.

It matches:
* Your torque curve
* Your converter
* Your actual RPM usage

If you want next, I can:
* Compare 3.73 vs 3.55 for your setup
* Predict exact stripe RPM
* Help you decide if this helps street driving too

Just tell me how often you drive it on the street vs track.