ACL Race Series Main Bearing Set, 0.25 mm undersize — ten tri-metal shells covering all five main journals of the 2.0 litre Theta II turbo block, sized for a crankshaft that has been reground 0.25 mm (0.010 in) below standard.
Read this first: this set is for a reground crankshaft only. Fitted to a crank at standard journal size it will clamp the crank and destroy the engine on start-up. Measure your main journals, or ask your machine shop exactly what they cut, before you order.
Grind the crank to the bearings, not the bearings to the crank. That is ACL's own guidance and it is worth following: measure the assembled bearing bores first, then have the journals finished to match, with the oil clearance you want. ACL also recommend confirming the undersize you need is actually available before the crankshaft goes into the grinder. This size is — but not every size in this family still is, so ask us first if you are planning a different cut.
Fitment — ACL's own application guide names the i30 N. Hyundai i30 N 2018 on, Veloster N 2019-2022, Elantra N 2022-2026 and Kona N 2022-2023 — 2.0L Theta II turbo (G4KH).
From ACL: tri-metal construction, with a lead-tin-copper overlay over a nickel barrier layer and a copper-lead-tin lining on SAE1010 high-tensile steel. Full 180 degree grooved uppers with matching partial grooves in the lowers, tapered groove run-out and enlarged chamfers.
Details: 10 shells, 5 upper and 5 lower, positions 1 to 5; 0.25 mm (0.010 in) undersize; block tunnel bore 56.000-56.018 mm; standard crank main journal is 51.942-51.960 mm, so a journal cut for this set finishes at roughly 51.69-51.71 mm — confirm against your own measurements, not against this line.
No thrust washers are included. Ten shells only. A crankshaft that has been reground usually needs its thrust faces addressed as well, so check thrust clearance on assembly.
Main bearings only. There are no rod bearings in this set.
A note on appearance. Race Series shells arrive dark and tarnished, with no cosmetic tin flash. Deliberate, not a defect.
Availability: ON ORDER at our distributor as of 6 November 2026.
Not sure this suits your car? Ask us before ordering — we would rather check the fitment than process a return.
Let customers speak for us
Solid shipping ,good communication ,great product 5stars all the way
First let's preface I have tried three other tuners. Not bad mounting or name dropping as they all were solid tunes. But Daniel just has that magic touch when tuning the 1.6 platform.
The car has a buttery smooth power band making the car feel like a larger displacement six cylinder over a turbo charged car. Plenty of fun to be had at any speed or RPM range.
He will take the time to get you dialed in perfectly for your car. No canned tunes here folks. And if you are a EK1 user three tunes for the price of one simply can't be neat.
I received the Stage 2 tune. Here are my thoughts:
- The shifts are buttery smooth
- I love the auto shift @2000rpm when cruising around town; saves me an extra 2-3mpg overall
- Driving in traffic is a dream now, much better than stock. I don't even hear that annoying shifting fork anymore, lol
- Any and all DCT slips are gone
- The increase in torque limit! This opened up my N75 Stage 3 ECU tune; I can feel the difference. The last time I dynoed, I got 289 lb-ft of torque. But it feels much more substantial than that!
- The clamping force is unreal. I did a run from a dig, and it hooked and slammed through the gears all the way to 7k rpm in each gear. Amazing.
Conclusion: This TCU tune is a must-have. If you have an N75 ECU tune, it is an absolute game-changer! Especially with the Redline MT-LV fluid that I'm running. I can't wait to get my retune with water meth injection. Daniel and the rest of the N75 team are the best!
Works like suppose to be fast delivery after installation 5 minutes drive TPMS sensors lights off everything is normal like from factory 👍👍👍
![Hyundai Elantra N TPMS Sensor Set of 4 [OEM Hyundai MOBIS]](https://cdn.shopify.com/s/files/1/0276/1359/3623/files/359598029_246649464881156_6848003515050026659_n_70x70.jpg?v=1690929846)
Product was very easy to install and what a difference in shifting also n75 was super awesome to deal with will shop here again
After using the N75 tune for a couple of months, I can confidently say that it offers the best value for your money on the market. I've tried SXTH and LAP3 tunes before, but since switching to N75, I won't look back. With top-notch customer support, it ensures your car performs better, turning heads at every car meet.
Been running stage 2 off that bat and had some problems here and their regarding fueling. Daniel has been with me the whole way, answering questions and adjusting tunes while adding revisions whenever asked. He answers every question I ask even when they don’t relate to tuning.
Highly highly recommend N75!
Daniel's tuning and customer service makes this product a 10 out of 10. I'm new to tuning and he made the process a breeze. I literally laughed out loud when I first drove the car after installing the stage 2 tune. I still can't believe the difference.
Love the intake, fitment is superb, instal was easy and best of all n75’s customer support is stellar and way above average!
M45IL Kia Stinger GT 3.3TT Spark Plugs
Hands down best bov I’ve had, I got the part 5207 for trumpet sound and man. You won’t be disappointed. Shipping was fast & easy.
Looks great!
Fast shipping, easy to install, quality built.
Waiting for some more parts then dyno time!
Awesome
Perfect size and great location for the WMI port.
