Transform your B18C GSR into B18C Type R performance

 

This is how to make your B18C GSR perform like a B18C Type R without doing a full engine swap or going wild with internal changes. 

Let’s focus on simple, proven upgrades that bring your GSR close to Type R-level power and response — around 190–200 hp (crank) or roughly 170–180 whp on a good tune.

Bonus Tip:

If your GSR is auto-trans, the stock gearing and torque converter will limit results — a manual swap (with LSD) is almost required to fully match the Type R’s driving feel.

TL;DR:

To make your B18C GSR as strong as a B18C Type R with simple mods:

• Swap to Type R-style intake manifold & throttle body
• Install Type R or mild performance cams + springs
• Add performance header & 2.5” exhaust
• Tune the ECU properly
  You’ll hit ≈ 190–200 hp crank and enjoy the rev-happy, aggressive VTEC feel of a real Type R.

Goal: Make GSR ≈ Type R Power (Simple Upgrades Only)

Here’s a practical, staged list of the best low-risk bolt-on and tuning upgrades — no bottom-end teardown.

1️⃣ Type R-spec Intake System

Why: The Type R breathes better; its intake manifold and throttle body are designed for top-end flow.

What to do:

• Replace the GSR dual-stage intake manifold with a Type R (PR3 or Skunk2 Pro Series) single-runner design.
  → Simpler, more efficient airflow at high rpm.
• Install a Type R or 70 mm throttle body (OEM or Skunk2/Omni).
• Pair with a cold-air intake (AEM, Injen, or custom piping with velocity stack).

✅ Gains: +8–12 hp at the top end, better throttle response and VTEC pull.

(Type R manifold is the #1 mod to wake up the GSR’s top-end.)

2️⃣ Type R or Aftermarket Cams + Valve Springs

Why: The GSR cams are milder; Type R cams open valves longer and higher, letting it rev and breathe better.

What to do:

• Drop in OEM B18C5 (Type R) cams or mild aftermarket Stage 1/2 cams (Skunk2 Pro 1, Toda Spec A, etc.).
• Upgrade to Type R or dual valve springs + titanium retainers (stops valve float over 8,000 rpm).

✅ Gains: +10–15 hp with proper tuning and supporting intake/exhaust mods.

(Even OEM Type R cams transform the GSR.)

3️⃣ Header & Exhaust System

Why: The Type R has a more free-flowing exhaust and header design.

What to do:

• Use a 4-1 or 4-2-1 performance header (PLM Tri-Y, Toda, Mugen replica, DC Sports).
• Add a 2.25–2.5” cat-back exhaust system (Buddy Club, Skunk2 MegaPower, Mugen, etc.).
• Optional: high-flow catalytic converter or test pipe (track use).

✅ Gains: +5–8 hp plus quicker VTEC engagement and lighter sound.

4️⃣ ECU Tune / Reflash

Why: Your GSR’s stock ECU is conservative; tuning unleashes the power of intake, cams, and exhaust.

What to do:

• Use Hondata S300, Neptune, or Crome tuned P72/P28 ECU.
• Retune fuel, ignition, and VTEC crossover for new airflow and higher redline (~8,200–8,400 rpm).

✅ Gains: +10–15 hp from proper optimization and smoother torque curve.

(Tuning is mandatory once you change manifold & cams.)

5️⃣ Type R-spec Clutch, Flywheel, and Gearing (Optional)

Why: Type R revs faster partly due to lighter rotating mass and shorter gear ratios.

What to do:

• Lightweight flywheel (≈ 9–12 lb) and performance clutch (Exedy Stage 1 or Type R OEM).
• If budget allows, use a shorter final drive (4.785) or a Type R transmission (S80 LSD).

✅ Gains: Faster acceleration, sharper throttle feel (no raw hp, but better performance).

6️⃣ Maintenance & Supporting Mods

Before pushing rpm:

• Replace timing belt, tensioner, water pump (if old).
• Use quality oil (10W-40 racing blend) and premium fuel (RON 97+).
• Upgrade ignition (NGK Iridium plugs, new wires).
• Ensure proper compression — a weak base motor won’t benefit much.

**Let’s go detail on a “B18C GSR-to-Type R Spec Conversion” parts list that’s:

✅ Simple bolt-on upgrades (no bottom-end work)

✅ Focused on reliability + Type R-level power (~190–200 hp crank / 170–180 whp)

✅ Practical for street or light track

⚙️ GOAL

Transform B18C GSR into Type R–equivalent power and response

Target: 190–200 hp crank (~170–180 whp)

Approach: Breathing + camshaft + tune + light rotating mass

1. Intake Manifold & Throttle Body Upgrade

Item	Recommended Brand/Model	Notes	Est. Gain
Intake Manifold	Skunk2 Pro Series Intake Manifold (B18C1)	Direct bolt-on; replicates Type R single-runner flow; more top-end power	+8-10 hp
Throttle Body	Skunk2 70mm Alpha Series or Omni Power 68mm	Increases airflow and throttle response	+2-3 hp
Gasket Kit	Hondata Intake Manifold Gasket (thermal)	Lowers intake temp for better density

2. Camshafts & Valvetrain

Item	Recommended Brand/Model	Notes	Est. Gain
Camshafts	OEM B18C5 Type R cams (or aftermarket like Skunk2 Pro 1, TODA Spec A)	Better lift & duration, more high-rpm pull	+10-15 hp
Valve Springs	OEM Type R dual valve springs or Skunk2/Toda	Prevents valve float >8k rpm
Retainers	Titanium retainers (Skunk2 / Supertech)	Lightweight, reduces stress

3. Header & Exhaust System

Item	Recommended Brand/Model	Notes	Est. Gain
Header	PLM Tri-Y Type R Replica or Toda 4-2-1	Best balance of midrange & top-end	+5-8 hp
Exhaust System	Skunk2 MegaPower 60mm / Mugen Twin Loop / Buddy Club Spec II	2.25” to 2.5” piping recommended	+3-5 hp
Catalytic Converter	High-flow cat (Vibrant / Magnaflow)	Maintains emissions, minimal loss

4. ECU Tuning Setup

Item	Recommended Brand/Model	Notes	Est. Gain
ECU	P72 OBD1 ECU (stock GSR) + Hondata S300 v3 module	Best flexibility, datalogging & tuning	+10-15 hp
Tuning	Dyno tune by reputable tuner	Optimize air/fuel, ignition & VTEC crossover (~5,800–6,000 rpm)

⚙️ 5. Flywheel, Clutch, & Drivetrain (Optional but Recommended)

Item	Recommended Brand/Model	Notes	Effect
Flywheel	Exedy Chromoly Lightweight (9 lb) or Fidanza Aluminum (8 lb)	Faster revving, improved throttle feel	Rev response
Clutch Kit	Exedy Stage 1 Organic / OEM Type R	Smooth engagement, higher clamp load
LSD Transmission (Optional)	S80 Type R LSD gearbox or rebuild with MFactory LSD	Better traction & shorter gearing

6. Supporting Mods / Maintenance

Item	Brand/Model	Notes
Cold-Air Intake	AEM / Injen / custom pipe + velocity stack	Better flow, cooler charge
Spark Plugs	NGK Iridium BKR7EIX	Reliable spark under higher load
Ignition Wires	NGK / MSD	Consistent ignition
Fuel Pump (Optional)	Walbro 255LPH	If you plan more upgrades later
Fluids	Motul 10W-40 / Red Line MTF	Stable at high rpm

7. Performance Summary:

	Approx. HP (Crank)	Approx. WHP	Notes
Stock GSR	170 hp	~145 whp
Bolt-ons only (intake, exhaust, tune)	185 hp	~160 whp	noticeable
Type R-spec full combo (manifold, cams, tune, exhaust)	195–200 hp	170- 180 whp	= Type R level
Fully optimized tune w/ flywheel	200–205 hp	180- 185 whp	Slightly above stock Type R

8. Approximate Cost:

Component	Cost Range
Intake manifold + TB + gasket	$550- $700
Cams + valve springs + retainers	$700- $1,000
Header + exhaust	$700- $1,200
ECU + Hondata S300	$550- $650
Tuning (dyno session)	$300- $500
Flywheel + clutch	$600- $900
Total (Full Type R-spec conversion)	$3,000- $4,500 USD

🔑 Key Takeaways

✅ Type R-level power is achievable on GSR without internal work.

✅ Prioritize manifold + cams + tune — that’s 80% of the gain.

✅ Keep the motor healthy — compression & oil pressure are key before tuning.

✅ You’ll have a rev-happy, high-strung GSR that performs like a true B18C5.