1449cc

[Sandy 191]

I always hope i'm understood, but you can never be sure !

[Guest JasonS]

Yea, i made that a bit hard to understand by saying full rod length being distance between centres

 

Going back to what i was suggesting, about the choice of rods therefore. I was saying that using the shorter TU3J rods (like matt has done) would leave you with better/stronger pistons, rather than the longer TU5 ones. I have both, and even though the TU5 rods might be stronger rods, it will result in weaker pistons. There's a compromise from choosing one or the other, Stronger Long Rods-Weaker Crown or Weaker Short Rods-Stronger Crown. I'm slightly pushed towards the second option, as i think that a richer mixture could be needed to prevent the crowns from being burnt/melting in the first option.

[Sandy 191]

I've not yet come across a piston failure in these, at least one that isn't directly related to to something else, like overheating. Rod failures with the later engines however seem quite common and the one's I've seen dismantled appear to have been straight forward break failures of the neck, no spun or seized bearings or seized pistons etc. So i'm not awfully keen on using the later slimmer rods in any build, but especially a long stroke one.

Edited December 15, 2006 by sandy309

[Guest JasonS]

Good point. Thinking about it again the first option could suit the setup better considering the change in bore/stroke ratio and the retention of a high rpm limit. I think the best bet would be to calculate the amount of decking required in both cases and go from there.

[bren_1.3 1]

is this for a road engine or for a class / CC limited race/rally engine?

[Mattsav 1]

The Quicksilver is a late (2000) Tu3Jp engine.

 

The rods and pistons are very light (the pistons is tiny compared to the XSI's) and they lasted Ok at 7500rpm but I have to say they didn't look very strong. As for Compression, we made a balls up with the calcs the first time and ended up with 12.??:1.

 

Then we dropped it to approx 11:1 from memory

 

The 270deg cam should work well on the 1400. Check the piston/valve clearance though as I can't give any guarantees!!!

[Guest JasonS]

is this for a road engine or for a class / CC limited race/rally engine?

 

Its only for a trackday car, no cc limitations.

 

The rods and pistons are very light (the pistons is tiny compared to the XSI's) and they lasted Ok at 7500rpm but I have to say they didn't look very strong. As for Compression, we made a balls up with the calcs the first time and ended up with 12.??:1.

 

Then we dropped it to approx 11:1 from memory

 

The 270deg cam should work well on the 1400. Check the piston/valve clearance though as I can't give any guarantees!!!

 

I think i might chance the standard TU3J Pistons and Rods. Matt, out of interest, with the 280 catcam you used, was piston/valve clearance ok with just decking or were cutouts required? What lift was that cam?