Supercharging An Mx5 Engine

[richardm6994]

now that my computer has sorted itself out....here I go again...

As mx5 engines are becoming ever more popular in kit cars, I've decided to do a build diary of my latest project for the benefit of anyone wishing to supercharge their Mazda lump.

 

The supercharger I'm using is the Eaton M65 (almost identical to the bmw mini eaton m45) from a Mercedes SLK. I will also be using the bypass valve from the mini M45 supercharger and an addition mx5 throttle body.....the rest is going to be machine / fabricated by yours truly .

 

The mazda engine I'm using isn't the engine that the finished set-up will be installed on. This is just a spare engine to help me make what's needed....the actual engine this will be going on is still in the owners kitcar (probably being polished ready for the charger).

 

Here is a photo of the supercharger. (not my photo, just nicked one from google)

Here is a photo of the mini bypass valve and second throttle body...

 

 

Ad here is where I'm up to in my first few days of working on it...First job was to cut the inlet manifold off and machine it flat...

 

and I've roughed out the first bracket to fix it to the engine...

It's difficult to explain the overall scheme....just what this space

[theduck]

Will watch with interest, love stuff like this.

[WallerZ]

Look forward to seeing this complete maybe follow it too!

[Guest old_timbo]

That's a Merc M45 that you've got there (750cc per rev). The M62 has longer rotors and is 1000cc per rev. The Merc M62's are the ones with the electric clutch, which makes changing the pulley size difficult.

[richardm6994]

Timbo, I never said m62

 

It's an m65 which is very similar to an m45...

[Guest mower man]

TGThats going to be mega ,Rich if its up to your usual stds ,will be following with much interest :clapping: mower man

[Guest old_timbo]

I've seen M65 used before but thought it was a mistake as Eaton don't list it on their website. Approx figures 45cu.in = 750cc, 62cu.in=1000cc, 90cu.in=1500cc 112cu.in. =1800cc. Hence the Eaton M45, M62, M90, M112 chargers. Main thing is you know its 750cc per rev.

What capacity is your engine? On my 2.0L Pinto with a M62 I'm getting 5 psi in the inlet manifold with a 1.5:1 drive. Probably loosing 1-2 psi through the intercooler and my rather space compromised charger outlet. Next step for me will be a 2:1 drive which is about the limit for the charger, after which it will just be making more heat. Might get 10psi which is about the limit for cast pistons anyway.

[richardm6994]

I must admiit that the supercharger being refer to as an m65 did cause me a bit of confusion to begin with. Whenever I looked up "m45", the images showed a different supercharger to what I've got.

 

I then stumbled across the m65 which was identcle to what I've got and further searches confirmed this.

 

I know what you mean about the m65 not being listed with eaton and so I don't know where the part number comes from.......but at the end of the day....it's basically the same as the m45 just with a different inet and outlet manifold and different mounting points.

 

The engine is a 1.8l and the drive ration is around 1.9:1. I've read that you shouldn't take these superchargers above 14k-15k rpm as the heat becomes an issue (just like you've said) and the needle bearing at the rear will fail.

 

I think a realistic target for this project will be aroud 7psi of boost.......and with a nice shiney intercooler and new ecu....should see an increase from 140bhp to around 220bhp.

[Tazzzzman1]

Rich

 

Benchmark for the standard performance will be set at Blyton this Saturday. So after the mod, we can see what the performance difference is in "real terms"....i.e how many changes of underwear per lap :rofl:

 

Cant wait mate

[Guest alfaGTA]

Heat generation........... You'll be wanting a charge cooled inlet manifold then

 

http://www.ebay.co.uk/itm/LAND-ROVER-4-2-SUPERCHARGED-O-S-INLET-CHARGE-COOLER-2W93-9424-BH-E9531000-NEW-/251297956621?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a8286830d

[richardm6994]

I've drilled and tapped the inlet flange on the charger. Because of the wall thickness in some places i was very "twitchy bum" when drilling to make sure i didn't break through the wall!! I've used m4 studs where the walls are thin and m5 for the rest.

 

I've roughed out the inlet pipe flange. This will also double up as the rear mounting point for the charger which is why it is thick and also why there is so much steel left on one side. Once I've figured out how the charger will be fixed to the engine the remains will be shaped to suit.

 

 

[Al Milton]

Marks & Spencer Outlet Store are doing an offer on underwear, might be advisable to spend a few extra quid at M&S.

 

Nice project and i'm sure you will do it proud Richard.

Will the charger sit on top aka US Street Rod or will the install be more 'subtle'?

[richardm6994]

Will the charger sit on top aka US Street Rod or will the install be more 'subtle'?

 

subtle. It's going on the side of the engine and the aim is to keep it all under inside the engine bay however it might need a small cut out in the side of the bonnet

[Shaft]

Are you about in the week Rich? Probably pop up and have a nosey at your project and a catch up mate.

[richardm6994]

Yes mate. Get yourself over any night