[shannon]

Has anyone ran these with the de head? was about to do an overhaul and now it time for upgrades:biggthump Also will these work well with S3's? And finaly what kind of fuel upgrade would i be looking at as far as injectors go? Or will the stock 259cc's hold their own

 

[shannon]

i guess what im asking before i get these are the valve reliefs deep enough so the valves dont crash using the S3's

anyones input would be of great help, thanks

 

[UK-SRi]

I think you will only need to retard the timing somewhat, an ECU mapping for high compression would be better, but it depends on your budget. I am going to be fitting some of those coated 11.6:1's soon, but I have to collect some other parts before taking the engine out.
I have a spraybar lowport with RR cams fitted, I think those will be ok, S3's should be ok, but I havent seen the numers for the lift limit of those. But they are designed for higher powered motors, so they damn well should be ok for s3's, but wait for a definative answer from someone who has fitted that combo.

Mike

 

[Red200Se-R]

all you have to do when you assemble it is use some PLAYDOH.. to figure out your piston to valve clearance.. hope that helps.

 

[shannon]

thanks for the help. what would be a good clearance be? .030?

 

[FastNX]

MY machinist told me to shoot for 0.060" in a race motor, but I have also heard 0.040" is good for street applications.

 

[dsp26]

fair enough thats JUST enough clearance but what about at high revs with the stock springs?

 

[FastNX]

To be honest, I doubt it should be a problem. IIRC these are the 20V pistons, whose cams have waaaaay more lift and duration than the S3s.

 

[shannon]

To be honest, I doubt it should be a problem. IIRC these are the 20V pistons, whose cams have waaaaay more lift and duration than the S3s.

They are from the 20V? I thought they were from the N1 sr16. does this mean that there will be 5 valve reliefs instead of 4?

 

[FastNX]

20V is just a name, it still has 16 valves. Why they chose such a misleading name is beyond me......

 

[howard_w13]

I was thinking about putting these in SR but I'm concerned about which thickness head gasket to get to drop the compression to 11:1......

 

[UK-SRi]

Just volume match, polish the combustion chamber, smooth off the sharp edge where the chamber begins with a 1or2mm radius and you should be good to go with a bit less advance.

Mike

 

[hybrid D E T]

The only concern is the difference in exhaust valve diameters between the DE and VE. The exhaust valve relief on the SR16VE mossy piston may be too small in diameter to accomodate the larger DE exhaust valve. However, if you take into consideration that the factory DE piston does not even have valve reliefs you would think that you would be ok.

 

[hybrid D E T]

20V is just a name, it still has 16 valves. Why they chose such a misleading name is beyond me......

It's an SR16VE piston not the 20V. The 20v is not a domed part and is more simular to the normal sr20ve piston with a small dish and valve reliefs.