Over 100hp per litre out of an old aspo Datsun straight six!


IT’S always impressive when a naturally aspirated engine makes over 100hp per litre, and even more so when it’s using an older-style engine. While we were down at Powerhouse Engines working on my Nissan RB30 turbo build (read about it in the August mag), we saw this stout Datsun L28 motor being run up on the dyno, making around 350hp.

 It might not sound like a lot in this day and age, but when you consider that this motor uses the standard cylinder head, factory rocker gear, and a stock size exhaust, it’s impressive.

The L28 started life as a 2.8-litre 12-valve in-line six, which Les from Les Collins Racing in Warragul has bored and stroked to 3385cc. The standard bore of the L28 is 86mm, but this one has been punched out to 89mm to take custom SPS pistons, and Les reckons on average he has to go through ten original Datto L28 blocks to find one that can handle being bored out so significantly. Likewise, the stroke has been taken from 79mm right up to 90mm with the use of shorter 137mm rods and a billet crankshaft.

 The whole thing breathes through triple 50mm throttle bodies and oversized stainless intake valves. This thing loves to rev and will happily spin up to 7500rpm, where it produces a peak output of 347hp. The motor is going into a Datsun 240Z owned by a customer in America. Yep, Les Collins Racing in Warrigal, Victoria has a few international customers. He reckons he’s even sent motors over to places like Norway and even Kenya!

Check out the video to hear this thing sing on the engine dyno at Powerhouse Engines.