1.2 crank in a 1.6

[mowgli]

having stood next to an evo with antilag at the midlands rally, and then been told by the man who builds the engines for it that they can cope with about 500km stage miles, and the fact that it is on the cars to get round regulations, there are way better ways to run a turbo car when the only restrictions are noise & emissions for an mot.

[bazil]

If the 8 and 16 valve rods are the same then I'll be going down the low comp route, with T25 or T28

[MK999]

Doubt it goes like diesel as the GM sportcompact LSJ build book shows you can build a 10Krev limited 1200bhp turbo engine with a relatively 'high' CR

Highest stress on a high revving engine is on the exhaust stroke when the piston attempts to exit from the conrod at TDC at about 80mph, it's why the stroke on F1 cars is so tiny, to keep the piston speeds down. So it's purely a function of the piston weight, conrod strength and how fast it's going. They rarely fail in compression as there's a nice chunky lump of conrod in the way, compared to the top/bottom edges of the little/big end which are much easier to break.

Maximum revs come down on a diesel most likely because there's much less torque up top and the power required to compress air that much that quick is a lot higher.

[bazil]

MK999, what's your opinon on the route of low comp leh pistons and rods giving a 8:5.1 in the 8v block?

As for camshafts, I'll worry about that later

[MK999]

MK999, what's your opinon on the route of low comp leh pistons and rods giving a 8:5.1 in the 8v block?

As for camshafts, I'll worry about that later

What I was planning to do (but 16v block, might be the same, not sure) but I haven't yet looked into how it effects squish areas etc. So basically I don't have one Was hoping someone else would have done it first by the time I came round to so I knew whether it was disappointing or not

[bazil]

Nice

a grand for pistons and rods for an experiment

1.2 crank would be much cheaper,

[MK999]

That's the other thing I didn't look into, was the cost, anything more than 2-3k ish for a properly rebuilt (bored, honed, rings, bearings, seals, could sell it as new) engine that will be reliable, and on standalone management would make it less worthwhile imo. To most people that wouldn't be worthwhile even as you can pick up a shonky LET for <£1k and it's an easy 200-250bhp. I like playing with engines though

[Stuart]

Dervs dont rev because of their long stroke, heavy as funk pistons and the fact diesel takes a sodding age to burn properly

[mowgli]

/\ and the fact that they don't need to rev to produce the power