diff --git a/package.json b/package.json
index 30bb7ce..6c11dff 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@tornado/tornado-oracles",
-  "version": "1.4.2",
+  "version": "2.0.0",
   "description": "Gas oracle for Tornado-specific transactions",
   "main": "./lib/index.js",
   "types": "./lib/index.d.ts",
diff --git a/src/feeOracle.ts b/src/feeOracle.ts
index cc41cba..aa8e2d8 100644
--- a/src/feeOracle.ts
+++ b/src/feeOracle.ts
@@ -48,7 +48,7 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
    * @param {TxType} [txType=other] Tornado transaction type: withdrawal by user, withdrawal by relayer or 'other'
    * @param {number} [bumpGasLimitPercent] Gas limit bump percent to prioritize transaction (recenlty used)
    * @param {number} [bumpGasPricePercent] Gas price bump percent to prioritize transaction (rarely used)
-   * @param {LegacyGasPriceKey} [speed=fast] Preferred transaction speed, if uses legacy gas (before EIP-1559)
+   * @param {LegacyGasPriceKey} [speed] Preferred transaction speed, if uses legacy gas (before EIP-1559)
    * @returns {Promise<GetGasParamsRes>} Object with fields 'gasPrice', 'gasLimit' and 'l1Fee'
    */
   async getGasParams(
@@ -56,10 +56,10 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
     txType: TxType = 'other',
     bumpGasLimitPercent?: number,
     bumpGasPricePercent?: number,
-    speed: LegacyGasPriceKey = 'fast',
+    speed?: LegacyGasPriceKey,
   ): Promise<GetGasParamsRes> {
     const [gasPrice, gasLimit, l1Fee] = await Promise.all([
-      this.getGasPrice(txType, speed, bumpGasPricePercent),
+      this.getGasPrice(speed, bumpGasPricePercent),
       this.getGasLimit(tx, txType, bumpGasLimitPercent),
       this.fetchL1OptimismFee(tx),
     ]);
@@ -73,7 +73,7 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
    * @param {TxType} [txType=other] Tornado transaction type: withdrawal by user, withdrawal by relayer or 'other'
    * @param {number} [bumpGasLimitPercent] Gas limit bump percent to prioritize transaction (recenlty used)
    * @param {number} [bumpGasPricePercent] Gas price bump percent to prioritize transaction (rarely used)
-   * @param {LegacyGasPriceKey} [speed=fast] Preferred transaction speed, if uses legacy gas (before EIP-1559)
+   * @param {LegacyGasPriceKey} [speed] Preferred transaction speed, if uses legacy gas (before EIP-1559)
    * @returns {Promise<HexadecimalStringifiedNumber>} Gas value in WEI (hex-format)
    */
   async getGas(
@@ -81,7 +81,7 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
     txType: TxType = 'other',
     bumpGasLimitPercent?: number,
     bumpGasPricePercent?: number,
-    speed: LegacyGasPriceKey = 'fast',
+    speed?: LegacyGasPriceKey,
   ): Promise<HexadecimalStringifiedNumber> {
     const { gasPrice, gasLimit, l1Fee } = await this.getGasParams(
       tx,
@@ -97,17 +97,14 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
 
   /**
    * Estimate next block gas price
-   * @param {TxType} type Tornado transaction type (to select correct default bump percent)
-   * @param {LegacyGasPriceKey} [speed=fast] Preferred transaction speed, if uses legacy gas (before EIP-1559)
+   * @param {LegacyGasPriceKey} [speed] Preferred transaction speed, if uses legacy gas (before EIP-1559)
    * @param {number} [bumpPercent=0] Gas bump percent to prioritize transaction
    * @returns {Promise<GasPriceParams>} Estimated gas price info in WEI (hexed) - legacy object with gasPrice property or
    * EIP-1559 object with maxFeePerGas and maxPriorityFeePerGas properties
    */
-  async getGasPriceParams(
-    type: TxType = 'other',
-    speed: LegacyGasPriceKey = 'fast',
-    bumpPercent: number = 0,
-  ): Promise<GasPriceParams> {
+  async getGasPriceParams(speed?: LegacyGasPriceKey, bumpPercent: number = 0): Promise<GasPriceParams> {
+    // Use instant for BSC, because on this chain "fast" and "instant" differs more than third and "fast" transaction can take hours
+    if (!speed) speed = this.chainId === ChainId.BSC ? 'instant' : 'fast';
     try {
       return await this.oracle.getTxGasParams({ legacySpeed: speed, bumpPercent });
     } catch (e) {
@@ -117,17 +114,12 @@ export abstract class TornadoFeeOracle implements ITornadoFeeOracle {
 
   /**
    * Estimate next block gas price
-   * @param {TxType} type Tornado transaction type (to select correct default bump percent)
    * @param {LegacyGasPriceKey} speed Preferred transaction speed, if uses legacy gas (before EIP-1559)
    * @param {number} bumpPercent Gas bump percent to prioritize transaction
    * @returns {Promise<HexadecimalStringifiedNumber>} Gas price in WEI (hex string)
    */
-  async getGasPrice(
-    type: TxType = 'other',
-    speed: LegacyGasPriceKey = 'fast',
-    bumpPercent?: number,
-  ): Promise<HexadecimalStringifiedNumber> {
-    const gasPriceParams = await this.getGasPriceParams(type, speed, bumpPercent);
+  async getGasPrice(speed?: LegacyGasPriceKey, bumpPercent?: number): Promise<HexadecimalStringifiedNumber> {
+    const gasPriceParams = await this.getGasPriceParams(speed, bumpPercent);
     return calculateGasPriceInWei(gasPriceParams).toHexString();
   }
 
diff --git a/src/feeOracleV5.ts b/src/feeOracleV5.ts
index 9b29a72..3bff8f6 100644
--- a/src/feeOracleV5.ts
+++ b/src/feeOracleV5.ts
@@ -49,16 +49,12 @@ export class TornadoFeeOracleV5 extends TornadoFeeOracle implements ITornadoFeeO
     }
   }
 
-  async getGasPriceParams(
-    type: TxType = 'other',
-    speed: LegacyGasPriceKey = 'fast',
-    bumpPercent?: number,
-  ): Promise<GasPriceParams> {
+  async getGasPriceParams(speed?: LegacyGasPriceKey, bumpPercent?: number): Promise<GasPriceParams> {
     // Only if bump percent didn't provided (if user provides 0, no need to recalculate)
     if (bumpPercent === undefined) {
       switch (this.chainId) {
         case ChainId.GOERLI:
-          bumpPercent = type === 'user_withdrawal' ? 100 : 50;
+          bumpPercent = 100;
           break;
         case ChainId.POLYGON:
         case ChainId.AVAX:
@@ -70,6 +66,6 @@ export class TornadoFeeOracleV5 extends TornadoFeeOracle implements ITornadoFeeO
       }
     }
 
-    return super.getGasPriceParams(type, speed, bumpPercent);
+    return super.getGasPriceParams(speed, bumpPercent);
   }
 }
diff --git a/src/types.ts b/src/types.ts
index 3457859..5f7f089 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -49,12 +49,8 @@ export interface ITornadoFeeOracle {
     bumpGasPricePercent?: number,
     speed?: LegacyGasPriceKey,
   ) => Promise<HexadecimalStringifiedNumber>;
-  getGasPriceParams: (type?: TxType, speed?: LegacyGasPriceKey, bumpPercent?: number) => Promise<GasPriceParams>;
-  getGasPrice: (
-    type?: TxType,
-    speed?: LegacyGasPriceKey,
-    bumpPercent?: number,
-  ) => Promise<HexadecimalStringifiedNumber>;
+  getGasPriceParams: (speed?: LegacyGasPriceKey, bumpPercent?: number) => Promise<GasPriceParams>;
+  getGasPrice: (speed?: LegacyGasPriceKey, bumpPercent?: number) => Promise<HexadecimalStringifiedNumber>;
   getGasLimit: (tx?: TransactionData, type?: TxType, bumpPercent?: number) => Promise<number>;
   fetchL1OptimismFee: (tx?: TransactionData) => Promise<HexadecimalStringifiedNumber>;
   calculateRefundInETH: (tokenSymbol: InstanceTokenSymbol) => Promise<HexadecimalStringifiedNumber>;