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

=== Assistant: This is the right question at the right time — now we’re talking about matching parts instead of chasing numbers. ===
This is the right question at the right time — now we’re talking about matching parts instead of chasing numbers.

I’ll explain exactly what a tighter converter + 3.73s would do in your specific car, and when it’s worth it vs not.

==== A slightly tighter converter with 3.73 gears will: ====
* Increase MPH
* Improve consistency
* Reduce RPM flare
* Make the car feel more “direct”
* Keep ET the same or slightly quicker if tuned correctly

But…
👉 If you go too tight, you will lose 60-ft and ET.

The key word is slightly.

==== You do NOT want a low-stall converter. ====

For your Buick:
* Current flash (estimated): 3,600–3,800
* Ideal tighter flash: 3,200–3,400

That’s only 300–400 RPM tighter, not drastic.

==== ### ====

What improves:
* Car feels more connected
* Less “rubber band” feeling
* Less RPM spike on hit

What you risk:
* If too tight → bog
* If matched correctly → no loss

With your torque:
* You can afford a slightly tighter converter
* Especially with 3.73s helping multiplication

📌 Expect:
* Same 60-ft or −.01 worst case
* Better repeatability

===== This is where tighter helps most. =====

You get:
* Less converter slip
* More torque transfer
* Stronger pull from 330–660

This is where ET drops without touching launch.

===== Right now: =====
* ~20% slip at stripe

With tighter + 3.73:
* ~10–12% slip

That’s free MPH.

Expected gain:
* +3–4 mph in the 1/8
* Engine RPM ~5,400–5,600 instead of 6,000

===== - Less heat in the trans =====
* Lower cruise RPM
* Throttle is more predictable
* Car feels less “jumpy”

For a street/strip car:
👉 This is a quality-of-life upgrade.

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

===== - 6.70–6.75 @ 101–102 =====

===== - 6.60–6.65 @ 102–103 =====

That’s knocking on:
* 10.30–10.40 1/4-mile potential

==== ✅ Worth it if: ====
* You care about MPH
* You want smoother street manners
* You plan to keep the car long-term
* You’re done with big changes (cam, heads, etc.)

❌ Not worth it if:
* You’re changing engine combo soon
* You only bracket race and ET consistency is “good enough”
* Budget is tight

==== If you ever order one, you want: ====
* Flash stall: 3,200–3,400
* Anti-ballooning plate
* Designed for big torque / Buick
* TH400 specific

Do not order by advertised stall alone — tell them:

: 

==== 👉 3.73 gears first (cheap, big gain) ====
👉 Converter second (only tighten slightly)

That order saves money and avoids mistakes.

If you want next, I can:
* Tell you whether your current converter is acceptable to keep
* Recommend converter brands/specs that actually work with Buicks
* Help you decide how far is too tight

Just tell me which direction you’re leaning.