850 Throttle body butterfly

[emm]

Hi all,

Does anyone know if the throttle body butterfly (the thing thats has that plastic wedge on it) is made out fo brass?

If not does anyone know what it is made out of?

Andy

[inde_house]

Please some one correct me if im wrong.....

I read somewhere that this part on the 850 is made of plastic. But the throttle body from the volvo 960 can be modified to fit the 850. And that throttle butterfly is a metal part.

And this modification had been described as changing the throttle to an on and off switch. Which improves spool up and throttle response.

But how does it affect the fuel consumption

[JUDGENINJA]

I think it is a composite similar to bakalite(remember the old plugs).
The only thing I can think it was any use for would be to assist the idling. give the control valve a bit more control to restrict air longer maybe?

Before I swapped mine to a 960 I filed the old one down and couldn't tell any difference

[T5frankie]

Please some one correct me if im wrong.....

I read somewhere that this part on the 850 is made of plastic. But the throttle body from the volvo 960 can be modified to fit the 850. And that throttle butterfly is a metal part.

And this modification had been described as changing the throttle to an on and off switch. Which improves spool up and throttle response.

But how does it affect the fuel consumption

its very controllable still, it does come "on song" alot quicker and fuel is the same

[emm]

I have a 960 plate but my throttle body plate that is currently fitted is smaller so can't use it. To make the 960 work I would have to port the throttle body and the manifold which is two expensive for a non t5.

On a side not

Did Volvo fit different plate sizes to different cars?

[woz]

I have a 960 plate but my throttle body plate that is currently fitted is smaller so can't use it. To make the 960 work I would have to port the throttle body and the manifold which is two expensive for a non t5.

On a side not

Did Volvo fit different plate sizes to different cars?
Yes - different engines, different throttle sizes.

But dont muck about trying to change just the plate and fiddle the TB to fit - just change the TB and plate as a complete set if possible.

If you want to go about modding the TB etc. David Vizard wrote an excellent book on modifying the A series engine. (I know, I know, its an age thing - but I do get cheap insurance;>) In it he talks about mods to the SU carb and the thorttle plate in particular. The basic principles apply to all engines, - it is about reducing the pressure losses from drawing air into the engine. The benefits are greater at higher revs obviously, and while gas flow at high revs is not really an issue with the T5 engines (just increase the boost!) anytihng which improves the suck at low revs/wide throttle will help torque before the turbo spools up and ALSO by increasing air/fuel mixture being burnt increases exhaust gas volume and hence speeds turbo spool up. (i.e. if your turbo starts to build boost at 2600rpm but you can tweak things so it spits out the same exhaust gas at 2400, then your turbo is going to come on quicker.

Thats all theory - I do have a big TB to go on Lusty, my T5, but not fitted it yet. However my experience is this - I followed Vizards advice on two motors (a Triumph 2500TC and a Maestro 1.6 ) and in both cases without any further setting up, RR tuining or even carb balancing, saw 2 seconds off the 0-60 times) Bear in mind both are n/a so the gains are more significant at higher RPM, we may not see the same % increase on a turbo engine but on your N/A engine it may be beneficial.

Even so, a couple of hours with a file, dremel, emery and oilstone are very cheap ways of extracting extra oomph, and because it comes directly from increased engine efficiency, you should see beenfits in fuel consumption in normal driving. Remember - 20% of teh effort gets 80% of teh benefits. So dont over do it.

Now the winter eveings are upon us I think its time to get that 960 TB installed and working, but I will get it working first then take it off and do the mods so we can see a before and after effect.

For my motor, the main aim has to be to get that turbo spinning at lower revs.

Do you have the variable geometry intake manifold on yours? Clever device from the looks of it - changing the plenum geometry to suit demand. I think it was used on the 20v n/a engines.

Both the t5 and 960 TB I have use metal throttle plates - I will check if they are steel or brass and let you know, def not plastic thougth. Shout if you need any pictures.

Woz

[emm]

Hi woz

Cheers for that the plate it self is going to be a one off custom. They are using my old one as a template and going to copy it exactly to match but without the wedge.

Mine is a 10v and from what i can see doesn't have the vvis (think that's what its called) otherwise I would do that mod as well.

I have a 960 throttle body with the plate but the cost of modifying would mean it would be cheaper to get a T5.

So my aim was to get a new plate and fit it to the existing throttle body, thus meaning no porting required. I've searched the net and found write ups but all either say buy a Turbo or just fit new plate. Non of them mention the plate being the wrong size.

Its my own fault for trying to mod a non T5.

Woz from your experience what are the things that in should be looking out for with just replacing the plate?

T5 Frankie is right from all the reading you gain no extra bhp your just increasing throttle response that's it. It allows a slightly more responsive pick up in the power band, but only by small fractions.

As always Please correct me if im wrong or send me a link as I'm new to modifying volvos so am just going on what I have learnt to dare and read.

Cheers
Andy

[emm]

Just a little update' the 10v n/a throttle body uses the same as a T5 but the manifold as I discovered today is larger.

If you have a 20v u will have a larger throttle body, the same size as the 960.

Does anyone have a throttle body from a 20v for sale?

[T5frankie]

Just a little update' the 10v n/a throttle body uses the same as a T5 but the manifold as I discovered today is larger.

If you have a 20v u will have a larger throttle body, the same size as the 960.

Does anyone have a throttle body from a 20v for sale?

i have one but its not mine, ask smithy

[emm]

Cheers frankie will do,

On a side note if I fit the larger throttle body will it cause any issues?

Plus can you fit a 20v throttle body to a 10v?

Andy

[T5frankie]

Cheers frankie will do,

On a side note if I fit the larger throttle body will it cause any issues?

Plus can you fit a 20v throttle body to a 10v?

Andy
much quicker throttle response, as long as you have a 3" inlet manifold hole

[emm]

Hi T5 Frankie, i've just been outside and measure the hole and it is 67mm. I have also measured the 960 plate and that is 65mm.

From my understanding the throttle body plate on the 20v is 65mm and with the hole on the manifold being 67mm, will it not fit?

Andy

[T5frankie]

The 960 is 78mm mate

[emm]

I've just measured the one I've got and its 65mm. I got a friend to measure his 20v throttle body plate and his is 65mm.

So i wonder what plate i have then.

On that note the Frankie does all 20v have 65mm plate or has my friend got an odd one? (no pun intended lol)

Ion a side note I will do a write up after to help anyone else as there seems to be on central place for this mod.

Cheers again for the help
Andy