Proton Triple valve - what's that all about ?

[Stan Part]

Sat in the rain in a queue of trafic waiting for the lights to change and notice the car in front isn't a Toyota but a early 90's Proton 1.6 Gl Triple Valve.<br>
<br>
<br>
Now the entertainments thin, the radio has Tina Turner screaming at me, so thought turn to the Proton, what is a Triple Valve - anyone know ? I assume there are 3 valves per cylinder but why and what do three do ?<br>
<br>
<br>
Anyone please ?<br>
<br>
<br>


<p></p><i></i>

[MaddMart]

At a guess, I would say they have two smaller inlet valves rather than one large one, thus the two smaller valves have a greater cross-sectional area than the one larger valve, thereby letting a greater volume of fuel/air mixture into the combustion chamber. But I'm sure you already knew that.<br>
<br>
I guess the question should be "Why bother on a Proton ?".

<p>Martin<br>
<br>
<!--EZCODE LINK START--><a href="http://www.dolomitesprint.com/" target="top">www.dolomitesprint.com</a><!--EZCODE LINK END--></p><i></i>

[2F45T4U]

Theres a 5 valve single cylinder motorbike engine! <!--EZCODE EMOTICON START :eek --><img src=http://www.ezboard.com/intl/aenglish/im ... ns/eek.gif ALT=":eek"><!--EZCODE EMOTICON END-->

<p></p><i></i>

[tinweevil]

Being pedantic for a moment its the circumference or total of circumferences of inlet valve(s) that counts. <br>
<br>
Audis, Ferraris and F1 engines have 5 valves per.<br>
<br>
Yup, I'm bored.<br>
Tinweevil<br>


<p>1978 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/704">Dolomite Sprint</a><!--EZCODE LINK END--><br>
1972 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/754">Spitfire IV</a><!--EZCODE LINK END--><br>
1968 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/705">GT6 II</a><!--EZCODE LINK END--><br>
1973 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/755">Dolomite Sprint</a><!--EZCODE LINK END--><br>
39 anorak points on the Nicholas scale<br>
</p><i></i>

[SprintV8]

3-valve engines <br>
<br>
The earliest mass production multi-valve engines were 3-valves because of its simple construction - it needs only a single camshaft to drive both intake valves and the exhaust valve of each cylinder. Today, there are still a few car cars using this cheap but inefficient design, such as Fiat Palio and all Mercedes V6 and V8 engines. Mercedes uses that because of emission rather than cost reason. <br>
<br>
<br>
5-valve engines <br>
<br>
It is arguable that whether 5 valves per cylinder helps raising engine efficiency. Audi claimed it does, but fail to provide evidence to support. In fact, its 5V engines are no more powerful and torquey than its German rivals with 4 valves per cylinder. <br>
<br>
Originally, 5-valve design doesn’t guarantee covering more head area than 4-valver. Nevertheless, if the head of combustion chamber is in irregular shape like the picture shown, the valves may cover larger area. Ferrari F355 make use of this to enhance high-speed breathing. Is there any disadvantage? Yes, faster breathing also harm low-speed torque if no counter measure is taken. Therefore it is more suitable to sports cars. <br>
<br>
All existing 5-valve engines have 3 intake valves and 2 exhaust valves per cylinder, still arranged as cross-flow. The exhaust valves are larger, but in terms of total area intake valves are larger. In F355, by arranging the outer intake valves open 10° earlier than the center valve, it got the swirl needed for better air / fuel mixture, hence more efficient burning and cleaner emission. <br>
<br>
The advantage of 5-valve engine is still under questioned. Not only few car makers used it (VW group, Ferrari and the bankrupted Bugatti), but Formula One cars also no longer favour it. Even the Ferrari F1 cars which was once famous for 5V engine has switched back to 4-valve design a few years ago. <br>


<p>1980 Dolomite SprintV8 (Soon to be shoehorned with a 360bhp TVR AJP V8 !)<br>
1997 Vauxhall Calibra 2.0 16v SE8 They laugh at me because I am different. I laugh at them because they are all the same!)<br>
</p><i>Edited by: <A HREF=http://p206.ezboard.com/bthetriumphdolo ... printV8</A> at: 3/12/05 1:48 pm<br></i>

[Jon Tilson]

the Sprint also has one cam driving 16 valves...<br>
with a cross over rocker effort we all know and err have mixed feelings about. I reckon its rubbish cos of the high wear and failure rate on rockers and cam lobes. Not may Sprints get to 6 figure milages on the orginal set. Plenty of Saabs with twin cams do double that with no obvious wear.<br>
<br>
As to the proton...well its one cam 12 lobes and Mitsubishi origins...<br>
<br>
V-Tec still rules though...with BMW VANOS a close second...<br>
Dont Alfa have some clever way of varying valve timing too on the 24 Valve V6?<br>
<br>
Jonners

<p></p><i></i>

[algtj]

Glad you mentioned SAAB Jonners, what do you think to a transplant.... It has crossed my mind in the past. I seem to remember something about the gearbox being a problem though, but I can not remember which engine it was!<br>
Can't help with the above, my V12's only rotate at about 3,400 RPM max and have 4 valves per cylinder.

<p></p><i></i>

[Stan Part]

Thanks people, It was what I suspected, just idle curiousity to see if I was correct.

<p></p><i></i>

[davepoth]

I looked into it. The engine should bolt up to a normal slant four bellhousing, as the gearboxes for all saab 99s and 900s look to be interchangeable throughout all the years. It gets a bit trickier after that.<br>
<br>
The very earliest Saab turbo engines might fit. They were called the B engine. It was substantially redesigned, but kept the original general dimensions. Later on they did another version called the H engine, which has bigger bearings and is longer, although I'm not sure of the exact dimensions. The link below should give you some idea, as this car would have had the 1850 engine originally.<br>
<br>
<!--EZCODE AUTOLINK START--><a href="http://www.demeis.com/motorsport/hardwa ... <!--EZCODE AUTOLINK END--><br>
<br>
also the Saab engine is the other way around in the engine bay compared to in a dolomite (Gearbox at the front of the car) so the turbo manifold won't work.<br>
<br>
Later engines were mounted transversely and were somehow made shorter. If this means you can wedge a 2.3 litre turbo engine capable of 300bhp under the hood, then it's very nice indeed,

<p></p><i></i>