Piston Size Question

[Zraced...]

I'm not a machinist, but was wondering what piston size my L28 F54 would need to be to make it a 3L. I want to buy the pistons from ITM and give them to the machinst. My guess would be 89mm. This is a turbo setup as well.

I think I will stick to the stock rods unless there is a better choice. Do they make forged rods? My setup is very adaptable as I can change the engine parameters with my Microtech ECU.

[240zwannabe]

yes you do need to use 89mm pistons. as for the rods http://www.datsunspirit.com sells a set of wako rods for a whopping $1250. you'll probably have to have some custom pistons made due to the fact that the wako rods are 7.2 mm longer than the stock l28 rods and 4.5mm longer than the l24 rods

[Zraced...]

Does anyone have the specs on the pistons with this rod setup? Also I'm guessing the 2mm headgasket would be best?

 

 

yes you do need to use 89mm pistons. as for the rods www.datsunspirit.com sells a set of wako rods for a whopping $1250. you'll probably have to have some custom pistons made due to the fact that the wako rods are 7.2 mm longer than the stock l28 rods and 4.5mm longer than the l24 rods

[240zwannabe]

man, i couldn't even tell you anybody who's running these pistons...

[dhartig]

Check www.ozdat.com/ozdatonline/enginedesign

 

It's a great link to trying different combinations of standard engine components and outputs displacement and CR.

[Austin240Z]

240SX pistons, 240Z rods, L28 diesel Maxima crank

[Zraced...]

Ok Here is what Eiji at Datsun Spirit wrote.

 

Just hitting 400HP on a dyno shouldn't be hard at all for a turbo setup.

Natural Aspirated 3.1liter L-engine is approaching that number nowadays.

 

>I was told lower compression is better for Turbos and if I go higher I

>would use less boost.

 

That's correct. For turbo (boost), you want lower compression. For Natural

Aspirated engine, you want high compression.

Weather turbo or natural aspirated, camshaft profile and the cylinder head

work is the single most important thing to consider in building an engine.

We can build crem de la crem, best in the world turbo or natural aspirated

head, if you are interested.

 

As for bottom end parts, I suppose you are seeking advice on the bottom end

setup?

For just 400hp setup, 3.0liter (w/ L28 crank & 89mm pistons) with our head

and our recommended camshaft, coupled with appropriate carburation/injection

and manifold & header should achieve that easily.

 

You want the top of the piston to be at par or slightly below the block

deck, (but not too much below the deck) and little adjustments can be done

with the metal gasket thickness (we can supply in 0.2mm increment). As for

pistons, shorter pin-height pistons is the way to go, my suggestion is 29mm

pin-height (38.1mm for stock pistons). Many people use dished pistons for

turbo setup, some use flat top pistons. Flat top pistons have much better

combustion efficiency than dish or dorm.

 

207.90 (block height) - L28 crank (39.5) + pistons (29mm) = 139.4mm.

 

We can supply 139.5mm chromoley rods or 138mm chromoley rods. Or if you use

32mm height pistons instead, you can use 136.7mm rods (and offset them if

needed), or use LD28 (41.5mm) + 136.7mm rods + 29m height pistons (0.7mm

below deck), etc etc etc. There are many many combinations we can do.

 

Having said all that, are you all fixated on a turbo engine? Natural

Aspirated L engine is very much fun, and N/A 320+hp engine is just as fast,

if not faster in 1/4mi than a 400hp turbo L-engine.

 

Eiji-