Basicly the same again. Same cam specs, H89 head, same turbo, standard head gasket, head studs etc. Just a small exhaust manifold change and a shorter inlet manifold. both more suited to higher rpm.

Sorry about the pic quality.

This is after playing with the boost controller yesterday. Its not falling over at the top end now.
I just need more revs

can you tell us more about the camshaft?

Quote:A standard A14 cam is 248/256, and a GX cam is 256/256.

I`ll grab the cam spec sheet and post it up.
I had a look at it the other day and realised that ive posted the wrong duration. Its actualy 236 deg at .050". So not as much duration as ive previously posted. Thats probably one of the biggest reasons it was falling over as much as it was. Ive increased the boost past where peak torque was to keep it holding torque. Its actually increasing from 16Psi at 5500 up to 22psi at 7200 to keep the torque curve climbing slightly.
Im guessing the Datsun duration figures that you have posted are "advertised" figures, not duration from .050" lift. There is usually about a 30 degree differance in duration between the two figures from memory.

Could that curve be improved at the bottom end or is the turbo too big?

if you have 22psi at high rpm then why not have it at the lower as well?

i would have thought you would taper boost down for reliability/stress reduction on motor. what is the theory behind running more boost at higher rpm? just the torque curve as you say?

Being a track car it wouldn't need heaps down low would it? It should spend most of its life in the mid and high rpm on most tracks- especially small capacity 4cyl turbo.

Mid range would be more important

sure, but not what im asking, he says 16psi@5500, 22psi@7500. i think its electronically controlled to do that, but why do that, why not 22psi@5500

Could it be a tuned version if traction control? So not to break traction in midrange but keep pulling in high rpm to keep up with larger capacity competitors?

I under stand high revs high boost not ideal with thermal loading and increased chance of detonation etc but seems Simons looking for more revs and more power up High.
Maybe cause he can lol.

Talk about eiffel tower like peak power within 1000rpm near the top this engine goes from 400-800hp thanks to boost.




high rpm 1.5 litre turbo