Well the recent discussion in the L series 1000 thread about lightweight motors really sparked my interest and I started reading up on some of the later model nissan motors that are pressure die cast as they are the lightest for capacity of the nissan motors, and the heads flow awesome. I really like the qr20de as suggested by D and think it would make a cool little motor for a 1200 and if I had have found one on trademe this afternoon for the right price I fear i would have brought it!
However I got thinking about a super lightweight Race coupe and started planning out a build (in my head of course :))
What i had in mind was a small capacity motor, somewhere around 1300cc with a blower or a turbo (or both if your a mad man!), all fibreglass panels lexan windows, H165 diff etc etc etc.
Anyway my (fantasy) research lead me to the cr series motors which are they latest small capacity pressure die cast motors in the nissan march's, cubes etc, since the cg13de only weighs in at somewhere around 60kg and is sand cast (read:heavy) a cr engine would be a seriously light motor.

ANYWAY the point of my ramblings is the cr series comes in 1L 1.2L and 1.4L so I was thinking for the guys in IPRA who wanted to stay in the under 2L class the CR12de would be awesome. They are 90hp standard and being a nissan motor they are tough as nails so would take to a healthy dose of boost so I reckon you could have a motor with an easy 150kw at the wheels on a unopened motor that weighs probably less than the A12 that came out of it!
Or if class limits aren't a problem get the extra capacity for pretty much no weight gain :)
they are fwd motors so work would need to be done with intake exhaust and gearbox, but if you can build a race coupe you probably have the skills to sort that one out too!

Anyway what do you guys reckon, you guys got any other cool ideas swimming round in your heads, lets hear them.
I expect D will have something to say, he's the lightweight engine research king!

Nick

How about an independent rear end?

How about someone woke up with there hand on it this morning. Maybe get out a bit more and meet some chics mate. Remember them mate chics you know.

Aha, I have considered these little rippers but my only reservation is only that they have some kind of vvl? if they dont great but the capacity needs to be around 1185cc x 1.7 to stay under 2030cc I think.
This would lead to ....de stroking.
So if you have the choice to destroke
I would go HR15de (if the vvl or whatever complex timing mechanism they might incorporate?) as the bores at 78mm would have better valve area for turbo and high end performance. However de stroking to 62mm from 78mm is a big issue so the CR12de is better.
Then availability is an issue as CG13de are common and for 5kg more block weight they still might be a better option with the thicker casting on walls and not forgetting simple timing no vvl etc.

Its a good idea, I think you could also cross enter into under 2lts sports sedans and without the restrictor.

I hadnt thought of the little micra engines when i started the engine im building for IPRA. There is plenty of hot up bits for them aparently.

But as D said they are small bore long stroke engines, hardly ideal for the 10,000 rpm they would need to be able to rev to before the restrictor realy takes hold.
When a small engine is used full boost wont happen until about 5750 rpm. ( when using a turbo large enough for 300+ hp).

That said, it still would be good to see one done.

suzuki g13 gti motor?

Dazza,
Be good for the street but for IPRA it must be a Dastun/Nissan block.

For the street id like to see a GSXR 1300 engine /gearbox in a 1200. A bitt easier for the folks in the US cos you have to move the taishaft tunnel to the right and run the diff centre offset in the housing. AKA-Ledgends race cars or Aussie race cars in Aus.

the HR15 would need 62mm stroke for its 78mm bore

One that I personally liked with old skool and modern lightweight and simple design is the MA series motors.

All alloy pressure die cast construction 8v hemi head already turbo in the MA10ET form the MA12S is supposedly an all alloy younger brother of the e15et.

The MA12S is the designation for the larger 1235 cc engine. It was used in the Nissan Micra K10.

* Displacement: 1235 cc
* Bore: 71 mm (2.8 in)
* Stroke: 78 mm (3.1 in)
* Maximum Power: 60 hp (45 kW) / 5600 rpm
* Maximum Torque: 94.0 N

Quote:

You have a point, to make it worth while to you IPRA boys you

They hr15 had the intake on the other side too doesn't it, so you could turn it RWD and you wouldn't have to redo your intake, unless they still point to the drivers side. It would be an expensive exercise to get a custom 62mm Crank though made, more work than most people would be prepared to do.