Titleist · Driver · 2021
TSi4
CaddyIndex™ breakdown — what the agentic research found across each of the six performance dimensions, with cited sources.
Scratch-to-mid-single-digit player with 105+ mph swing speed who naturally spins it 3,000+ rpm and wants tour-style shot-shape control.
You swing under 100 mph, miss the center regularly, or have a normal-to-low spin profile — the head will leak ball speed and forgiveness for no benefit.
Pros
- Ultra-low spin — ~1,964 rpm in independent testing, ~250 rpm under the TSi3 and ~130 rpm under the TS4
- Most workable head in the TSi family — the compact 430cc pear lets skilled players shape both directions
- Distinct, crisp acoustic and substantial feel — the best feedback in the TSi line
- Class-leading wind tool: low spin plus a flatter trajectory penetrates the breeze
Cons
- Least forgiving driver in the TSi family — the smaller head sacrifices heel / toe MOI
- Requires 105+ mph swing speed and high natural spin to actually benefit
- No movable weight track (single rear weight only) — the TSi3 carries the bias-tuning hardware
- Now four years old — superseded on speed and MOI by the TSR4 (2022), GT4 (2024), GTS4 (2026)
By dimension
Forgiveness
Independent reviewer testing confirms this is the least forgiving driver in the TSi line. The compact 430cc head and low/forward CG sacrifice perimeter MOI for spin reduction — the head demands accurate swings. The family's 13% top-to-bottom MOI gain helps on vertical mishits, but heel/toe stability remains the family's weakest. Below-average forgiveness vs the same-year category — correctly so for an ultra-low-spin tour head.
Distance
Independent fitting testing: 145.8 mph average ball speed at 100 mph swing, with several shots exceeding 150 mph. Ultra-low spin (1,964 rpm, ~250 rpm lower than the family workability sibling and ~130 rpm lower than the prior generation low-spin head) maximizes rollout for high-spin players. Aerodynamic shaping reduces drag 6% vs prior generation for higher head speed. For high-spin tour players this is class-leading carry+roll; for everyone else, distance is left on the table.
Workability
Manufacturer and independent reviewer testing both flag this as the most workable of the TSi family. The compact 430cc pear shape plus low/forward CG let skilled players manipulate face angle through impact, producing fades and draws on demand. The reduced size makes the head more rotationally responsive than the family's higher-MOI siblings — tour-style shot-shape control.
Feel
Reviewer testing reports a substantial, balanced metal-wood smack with the most distinct feedback of any sibling — feel is a strong indicator of contact location. Off-center vibration is intentionally pronounced — noticeable increase in vibrations through the hands — what better players want from a tour head. Premium tactile profile rewarding accurate strikes.
Sound
Reviewer testing reports center strikes have a distinct crispness with informative mishit acoustic feedback (higher-pitched on misses than center). Manufacturer notes 'improved sound and feel' as a model-specific upgrade. Crisp, sharp, premium — slightly more aggressive than the family workability sibling's mid-bass boom.
Looks at address
Manufacturer and independent reviewer testing all flag a 430cc classic, small pear-shaped profile — the smallest, most tour-spec address shape in the family. Looks like a player's driver from address. The compact silhouette is a deliberate visual cue for the better-player target. Class-leading address aesthetic for the low-spin tour-driver segment.
Sources
Some of the reviews, lab tests and head-to-head comparisons the agentic research read while grading this club.
- Titleist TSi4 Driver, TSi1 Driver and TSi1 Fairway Wood
- Analyzing the last three versions of Titleist drivers with a swing robot
- Titleist adds TSi4 driver and TSi1 driver, fairway wood, and hybrid
- Titleist TSi4 Driver Review - Low-Spin Distance
- How to gain ultra-low spin with the new Titleist TSi4 driver?
- Titleist Introduces New TSi4 Driver
- Titleist TSi4 Driver Review