What cams?

[payton31]

I have a c2 vts with tu5jp4s engine, can help in feeling that my old 106gti/vts was a lot more aggressive,

I’ve searched a few threads regarding this

Can I put j4 cams, retainers and springs in and expecting a good power gain ?

What are my options ?

[MartinObviously]

Originally Posted by payton31

I have a c2 vts with tu5jp4s engine, can help in feeling that my old 106gti/vts was a lot more aggressive,

I’ve searched a few threads regarding this

Can I put j4 cams, retainers and springs in and expecting a good power gain ?

What are my options ?

No you can't expect a good gain at all.

It feels flat because the JP4S has better valves and camshaft profile, so has much better torque and more efficiency. Putting in J4 cams will only make it slower.

People used to think that if you fitted J4 cams to a JP4 you'd suddenly get the same power as the old J4... nope.

Could maybe jsut get yourself some JP4S high lift cams?

[payton31]

Yeh that’s the opinion I was getting/ mixed answers, been reading then about piston clearance

[dturbo]

Originally Posted by MartinObviously

No you can't expect a good gain at all.

It feels flat because the JP4S has better valves and camshaft profile, so has much better torque and more efficiency. Putting in J4 cams will only make it slower.

People used to think that if you fitted J4 cams to a JP4 you'd suddenly get the same power as the old J4... nope.

Could maybe jsut get yourself some JP4S high lift cams?

Hi Martin,

Wonder if you could expand a little on this? It's probably just me reading this wrong, but I am a bit confused. Reason I am interested is that my Saxo VTS came with a JP4S engine fitted to it.

You seem to be saying that the JP4S engine, with it's own cams, has more torque than the J4 and this is why the JP4S feels less powerful?

I'm missing something

[MartinObviously]

Originally Posted by dturbo

Hi Martin,

Wonder if you could expand a little on this? It's probably just me reading this wrong, but I am a bit confused. Reason I am interested is that my Saxo VTS came with a JP4S engine fitted to it.

You seem to be saying that the JP4S engine, with it's own cams, has more torque than the J4 and this is why the JP4S feels less powerful?

I'm missing something

When I say it makes more torque, I mean torque as a quantity not a peak value. you're not going to feel 6nm difference in torque. It's all in the power delivery.

J4 needs to be revved hard to go anywhere, a JP4S doesn't by comparison.

point is, you wouldn't fir J4 cams to a JP4S because it's just not the right cam for that engine. You'd just buy aftermarket high lift cams for a JP4S.

[dturbo]

gotcha. Makes sense, thanks Martin.

[MartinObviously]

Originally Posted by dturbo

gotcha. Makes sense, thanks Martin.

No worries, that's my understanding of it anyway.