My supercharged LE5 in my Miata is pretty dead. I've decided to go to a fully built motor. I'll keep the M62 for now and move to a turbo or TVS later to keep the budget focused on the engine. Moving to turbo now would just be too expensive.

What would you do? There are so many options. I can do LSJ, such as the ZZP race block. Go LAP with forged internals. 3rd gen LE5? Honestly I don't even know where to start and want to get the best bang for me buck given I'll drop $5k-7k.

Power goals, 300hp with M62, I make 270hp now on my LE5, go to 400-450 on tvs or Turbo. Car is full time attack car. Not street legal.




Thoughts?

 

I would go with a built lsj engine and then turbo later on. Its overall a stronger engine and can make great power and are pretty available compared to the LNF engine which has the porus block issue in stock form. Built le5 is another good option but you can make more power cheaper right away with a lsj engine. Just my 2 cents. And I love your build brother. Always liked those generation Miatas. Light chassis and when tastefully done is an absolute blast on the track and back twisty roads. Can't wait to see your progress on your build. Myself I been restoring my Pontiac G5 GT for the last three years now. I've done full suspension upgrades, brake upgrades with new OTTP braided steel lines, upgraded stainless fuel lines also from OTTP and I'm doing the M62 supercharger swap on my le5 engine as well which is a stage 2 ported blower. Here is a pic of my car its sport red tint coat color. Canada got the GT Sedan model while USA just got the coupe version.

 

I would decide if you want to stay supercharged or change to a turbo setup. The engine build is going to be different if you want to get the most out of the engine. You can probably get away with running an engine setup for a turbo with the m62, but it would negatively impact your ability to get to 400-450 on a TVS.

I'm assuming you're running e85 or e100, I'd recommend building the head so you can rev things out to at least 7500rpm. As well as getting porting work done, the ecotec heads flow like poop in stock form.

Either route you'll want to delete the balance shafts Then if you're going supercharger get the oversized drive pulley, going turbo get the underdrive.

Given you can probably push some serious g-force in the corners, I'd look into a dry sump system or at a minimum a baffled oil pan.

@5-Speed any recommendations/guidance for what OP is looking for? Or maybe you have an engine already built OP could use.

 

If you're wanting to buy a built block, ZZP is likely your best option.

Swapping from an LE5 to an LSJ won't be a simple swap though. There are wiring harness differences between the two - not sure how your car is setup or how easily you can rewire.

Honestly, I'd probably just spring for a built LE5 if I was in your position.

A stock LSJ block, crank, and rods with forged pistons will hold all the power you want though. Get the head ported (search Category V Port Worx on Facebook or Instagram; he's an old friend, best in the community though) with upgraded valve springs and lash adjusters, and then you can rev to 8000.

 

I would keep that 2.4L block and throw a LNF crank in it (h-beam rods and custom pistons). Some good Supertech valve spring, big nasty cams, port the head, small pulley (2.7") on the current blower and send it. Should be able to turn 8500rpm no problem. The blower isnt big enough to do big boost on a 2.4L so you really need to go smaller on the displacement. It will help with a smoother powerband which should help in time attack.

 

Sounds like you have a solid plan! Keeping the 2.4L block and upgrading it with LNF connecting rods, h-beams and pistons is a smart move. Adding Supertech valve springs, larger cams, and porting the head would definitely help improve performance. By the way, who's gambling? I recently found Club World Casino no deposit bonus https://casinosanalyzer.com/casino-b...rldcasinos.com and want to try playing, do you think it will work? Installing a smaller pulley (2.7") on the current supercharger is a good idea, as the supercharger may not be able to handle the large boost on the 2.4L engine. By reducing the displacement, you will achieve a smoother power range, which is very important for time-attacks. All in all, the modifications you suggest should allow you to accelerate to 8,500 rpm with no problem. Nice to see your enthusiasm and knowledge of engine upgrades. Best of luck with your project!