Technical How old is this timing belt?

[vexorg]

It's useful to think of this "problem" in this way because no matter how "hard" the piston tries to "suck" the air into the cylinder you can't get more than a 14.7 lbs/sq in pressure differential between the outside of the engine and inside the cylinder which must, no matter what you try to do by way of camshaft and inlet design, be the final limiting factor.

You can get higher that atmosphere in the cylinder under right conditions, effectively the race tuned engines are optimised for a specific band and in that band, the momentum of the flow of air can push more than 100% VE (volumetric efficiency).

Not really practical for a road car, and why vhanging the valve timing can help move towards that.

 

[Pugglt Auld Jock]

I get that, thanks. One last question - is the extra mass in the pulley just mass, electronics or something else?

It's hydraulic with moving parts. Try you tube, there are some videos which describe it with animation much better than I can here in words.

I have found a timing belt tool set for the non vvt 1.2 L 8v for £11. Won't do the 1.4 but I can get that later.

All good

Be interesting to see an illustration of that £11 set? The ones I've seen at this price point are very basic and I doubt if you can buy just the "extra" bits you'll need to do the VVT engine on it's own so you might be better to buy a more comprehensive kit now and just have done with it?

 

[Pugglt Auld Jock]

You can get higher that atmosphere in the cylinder under right conditions, effectively the race tuned engines are optimised for a specific band and in that band, the momentum of the flow of air can push more than 100% VE (volumetric efficiency).

Not really practical for a road car, and why vhanging the valve timing can help move towards that.

Yup, high lift and long duration allowing some ram effect and produces power over a narrow rev range and usually at very high revs so, as you say not really practical for a road going engine. I always liked Honda's VTEC and even more interestingly, for everyday use, their i-VTEC as used in the normally aspirated 1.8 Civic engine. Very clever when you go into it in some depth.

 

[jte]

Hi,

Here is the explanation how the VVT works.

INTRODUCTION - TIMING SYSTEM - Fiat - GRANDE PUNTO - eLearn - 4CarData

 

[vexorg]

A 1.2 16v would have given a better engine, more power and less hassle

 

[AnthonyH]

It's hydraulic with moving parts. Try you tube, there are some videos which describe it with animation much better than I can here in words.

Be interesting to see an illustration of that £11 set? The ones I've seen at this price point are very basic and I doubt if you can buy just the "extra" bits you'll need to do the VVT engine on it's own so you might be better to buy a more comprehensive kit now and just have done with it?

The £11 toolset is here;

Camshaft Timing Tool for Fiat 500/Punto Evo/Panda/ Engine 1.1 1.2 1.4 Litre 8V | eBay

Grande Punto (2007-2008). Timing Tool Kit for locking camshaft and crankshaft when changing timing belt on Fiat and Chrysler 1.1 Eco, 1.2 and 1.4 8V liter petrol engines. - Panda (2003-2012). -1,1, 1,2 and 1,4 8V liter.

www.ebay.co.uk

I can get another toolset for the 1.4L engines for £23, so all in it works out a little cheaper than Nielsen set you bought which are £41. It is possible your set is higher quality, the tradeoff is that I'd be getting two possibly lower quality sets.

 

[AnthonyH]

Hi,

Here is the explanation how the VVT works.

INTRODUCTION - TIMING SYSTEM - Fiat - GRANDE PUNTO - eLearn - 4CarData

Thanks for that. I wasn't expecting to see engine oil inside the pulley or any hydraulics. I like.

 

[vexorg]

I know some cheaper ones don't quite fit as well, I have a vauxhall corsa one that needed a little tweak or two to make it all fit in. Not affecting hte timing in any way, more to holes didn't quite line up with the head.

 

[AnthonyH]

I've noted the quality problem myself, and others have also mentioned buy good quality tools. I'll have another look.

 

[Pugglt Auld Jock]

I've noted the quality problem myself, and others have also mentioned buy good quality tools. I'll have another look.

I'm very happy with the Nielsen set I bought. Robust and "nice" to use. Bergen seems to be an equivalent brand name and I have a number of tools from this brand, sockets etc, all good quality and have withstood some pretty extreme usage.

 

[Pugglt Auld Jock]

Thanks for that. I wasn't expecting to see engine oil inside the pulley or any hydraulics. I like.

Warned you, much earlier in this thread, to be ready with a wad of cloth, to catch the oil when you remove the plug in the middle of the cam pulley on VVT pulleys. It's only oil inside the pulley so not a great deal but makes a bit of a mess if you're not ready for it.