8v vs. 16v

Currently reading:
8v vs. 16v

Excellent recollections there Mr. Beard (y)

The Dolly Sprint was unusual because unlike the Italians with 2 cams and 2 valves per cylinder, the Triumph had only one camshaft but 4 valves and was possibly the first truly Sporting saloon. Top speed of about 120 and 0-60 in around 8 seconds from 127bhp. Pretty impressive for 1978.

Dolly Sprint was released in 1973 ;)

Not much in the Dolly Sprint class could touch it, other than sporting saloons like the BMW '02 series. The 2002 was quite an impressive car for it's time though the sporty models if I recall correctly were only available as two doors. Some info. about them on Wiki (sorry!) here:

"The 2002 is one of BMW's most famous automobile models. While the 1500 had begun BMW's reputation for sports sedans, the 2002 may be considered its ultimate incarnation.

A two litre version of the Michelotti-designed two-door 1600, it cemented the company's reputation for compact sporting sedans and served as both forerunner of the BMW 3 Series and inspiration for the new 1 Series Coupe.

With its 1990 cc engine, it produced 120 bhp (88 kW) in the 2002ti, and 130 bhp (96 kW) in the high-performance 2002tii, offering a top speed of 185 km/h (115 mph). The 2002 Turbo was launched at the 1973 Frankfurt Motor Show. BMW's first production turbo, it produced 170 hp (125 kW) at 5,800 rpm, with 240 Nm (177 ft·lbf) of torque.

A three-door 2002, the Touring, was also available. The Touring was not a full station wagon, resembling a modern hatchback. BMW would not offer a Touring model again until the late 1980s, with the 3 Series. A cabriolet version was produced in small numbers by Baur of Germany, which to this day as IVM Automotive, continues to convert BMWs."


[ame]http://en.wikipedia.org/wiki/BMW_2002[/ame]


Other sporting saloons of note from around the same era were possibly the Alfa Romeo (1750 and Giulia) and Lancia (Fulvia and 2000) models, or even cars like the Rover P5B, P6 3500S and SD1 3500 though the Rover models were firmly in the executive car sector rather than the sporting saloon sector.

Once you got away from homologation specials like the Chevette HS/HSR, RS 1600/1800, Sunbeam Lotus and their ilk it was probably the late '80s or early '90s before Vauxhall, or almost anyone for that matter, had a series production 16v and even Ford's Sierras only had a 2 valves per cylinder despite having DOHCs.

The Ford DOHC I4 engine (pre-Zetec) that replaced the Pinto in the Sierra and Granada/ Scorpio WAS available as a 16 valve! Early models were 8 valve but then subsequent models were 16 valve. More Wiki (sorry again!):

[ame]http://en.wikipedia.org/wiki/Ford_I4_DOHC_engine[/ame]


I remember road tests of the time comparing current same spec models of Sierra available with both the old Pinto engine and also the new 16v DOHC engine. One test involved drivers testing both cars but without knowing which engine was under the bonnet. They were asked which car felt quicker and nicer to drive and the unanimous verdict was the old 8v Pinto was the better car, even though on paper the 16v DOHC was both more powerful and quicker.

But as someone pointed out, one of the main reasons for using 16 valve heads today is that they are more efficient and thus have lower emissions than an equivilent 8 valve head. With the right engine set up a 16 valve engine will be more powerful than an 8 valve simply because of better flow rates though without modern engine management/ VVT etc. an 8 valve will generate more torque lower down the rev range and thus feel easier/ more gutsy to drive.

If I ever get round to doing the 1242 16 valve conversion on my Uno it will be interesting to compare its driving characteristics with my 1301cc 8v 70SX. I wonder if the 1242 16v will feel less torquey lower down the rev range? :chin:

Had both 8v and 16v Cavaliers years back and the differences were quite noticeable. If you wanted to make less gear changes then the 8v was a good choice, however, if you want to overtake lots of caravans on the Snake Pass, the 16v would be a better idea. More top end.

The early 16v Cavalier used the legendary C20XE engine if I remember rightly? A great engine and regarded as one of the best out of the hot hatch engines in its time. It made the mk2 Astra GTE 16v something of a rocket but a shame it didn't have a chassis to cope with the power! :eek:
 
So is my almost fixed 12 valve better because its in between :D

Why dont some of us measure our valve diameters. My exhaust valve is massive.

Mine has 8-inlet and 4-exhaust.

so how did the 12v behave?(when it was working) was it the same amount of punch all the way through or pick up significantly near a certain rpm etc? is it spi or mpi?
 
so how did the 12v behave?(when it was working) was it the same amount of punch all the way through or pick up significantly near a certain rpm etc? is it spi or mpi?
Im not sure what to say because I never pushed it hard then it broke down. Ill let you know what the rebuilt engine is like. But it was always good at low rev's. I have the power curves for my engine here.


 
16v got to win hands down with Honda taking it to another level,

with different series of honda 1.6 16v engine (B16 series) it produces 160 bhp in the civic VTI and 185 bhp on type r (ek9)

Not many have managed to produce an mass produce N/A engine with 10cc/ 1 BHP! (regardless if it is 8v or 16v)

Ming
 
It is easy to see that low valve number equals better torque at low revs on a "normal" engine.
 
It is easy to see that low valve number equals better torque at low revs on a "normal" engine.

Same on a v8 I think, not usually revvy stock, but would pull tree stumps out at tickover!
 
16v got to win hands down with Honda taking it to another level,

with different series of honda 1.6 16v engine (B16 series) it produces 160 bhp in the civic VTI and 185 bhp on type r (ek9)

Not many have managed to produce an mass produce N/A engine with 10cc/ 1 BHP! (regardless if it is 8v or 16v)

Ming

Aye but at the great expense of torque and drivability!. They feel slow unless you driving them like a 16yr old pikey who's just stole it :devil:
 
Audi's FSI V8 in the RS4 rev's to 8500rpm, the noise is spunk worthy :yum: :devil:. I heard a supercharged one on youtube and I had to wipe the jizz of my monitor :rolleyes:

Higher revs due to more valves per cylinder but still loads of torque low down due to V* and cc capacity. Oh and FSi helps loads too :slayer:
 
Back
Top