Looking to go 176MPH in your MX5? With enough power and a 6 speed box that’s how fast you’ll be going at 7200rpm using the 3.3:1 gearset.
Perhaps you’re not looking to go that fast but you’ve turbo’d the car and the gears are going all too fast and maybe you want to run a lower and quieter rpm on the motorway.
We’ve installed a 3.3:1 gearset in our 300BHP 1.8 NA using a 6 speed box. We chose the 3.3 as it gives the closest experience to a 5 speed with a 4.1 differential, but with the benefit of a huge overdrive in 6th, letting you cruise at 2860rpm at 70mph and 3270rpm at 80mph. Thats considerably less than our 5 speed 4.3 car, which sits around 3600rpm at 70mph and 4050rpm at 80mph.
Note the graph below, red is 5 speed 4.1 and blue is 6 speed 3.3, very little difference in acceleration but with a huge overdrive.
There are now also other final drive options available! These include 3.3, 3.9, 4.44 and 4.57. If you wanted to see how these look in comparison to your current setup, you can use this handy calculator:
http://grafgarage.com/gearing-calculator.html
In our test above, we’ve used the tyre size of 205, 15 R15.
Please note suits differentials with 7in ring gears found in NA 1.8 & all NBs only. Does not fit NA 1.6 cars unless the diff, prop shaft and driveshafts are also changed.
Features
- 3.33:1 final drive
- Includes matching ring and pinion gear seat
Warranty information
Warranties cover defects in materials and workmanship only. Warranty is for replacement of a similar product, repair of the original product or refund of the purchase value only and excludes all labour and incurred charges including towing, fitting, inconvenience, and purchases of other manufacturer's products. The warranty is good for the period stated in the additional info tab from the date of purchase. Mileage warranties are for road use only and proof of mileage is required. Products must be installed by an independent experienced professional mechanic and the suspected defect must be present at the outset. The warranty does not cover damage caused by incorrect installation, failure to comply with the maintenance requirements of the vehicle, processing or otherwise changing the product, ordinary wear and tear, or any other external influences. Warranties are invalid if the product is used for racing, rallying, drifting, track days or any other form of motorsport or competition. Please refer to the manufacturer's own warranty documentation for more information.
Making a warranty claim
Proof of purchase receipt showing the date of purchase, proof of mileage at installation, proof of current mileage and invoice of the work undertaken by an independent experienced professional mechanic must be supplied along with the returned products for a warranty claim to be considered. If your vehicle needs to be used whilst your warranty claim is considered replacement parts from the same manufacturer should be purchased through BOFI Racing. In the event of a successful warranty claim, we will refund the card that was originally used to purchase the replacement parts, in full or in part depending on the nature of the claim. BOFI Racing reserves the right to make full or partial compensation at its sole discretion depending on the condition and mileage use of the returned suspect parts. For example, if you have used the part for several thousand miles before a defect is noticed, only partial compensation may be offered.
