aimed at redmist etc: What does a b16 have over a 4age??

[soopachargen]

My question, after reading the thread on circuit levins car is what have honda done with the b16 that makes it "superior" to the 4age? What differences are there in design that they make N/A power so much easier? I dont want an arguement over which is best, i want fact rather than opinion. Please come forth and discuss kind folk with technical knowledge. (mods please feel free to prune anti-honda BS from this thread)

[86_rolla]

i no absoloutly nothing about engines or the technical side of cars but i am going to say Vtec

[crnkin]

b16s have good bottom end torque due to off vtec cam profile, good top ends due top vtec high lift profile, and they are blueprinted engines from the factory. Also nice and wide cam design like 4age so the air has good flow into and out of the valves and combustion chambers.

makes a superior engine in a disappointing line of cars.

[Rick]

My question, after reading the thread on circuit levins car is what have honda done with the b16 that makes it "superior" to the 4age?

Who says they the B16 are superior, they pretty much have the same hp and torque as a 20v so I dont see why they are any more superior. The B16 found it TypeR's is alot grunter but thats because they come out with better components and are more refined and tuned.

have a read here:

http://www.billzilla.org/vvtvtec.htm

[Ako]

The 20V "in theory" makes the same power + torque as a B16A.

In practise.... No. I still fully reckon toyota does the old 60's trick of rating power figures without ancillaries on the engine

As for reasons why - as noted. The 20V is more of a mass produced engine, and isn't really marketed as a "go fast" type, whereas one of the B16/B18/whatever's main marketing ploys is having the economy WITH power, so they kinda have to deliver. Hence the blueprinted engines in Type R spec etc, even in normal shopping trolley spec there isn't that many gains to be made over what honda has already wrung out of the little beggars.

[Grrrrrrr!]

As much as i hate to admit it, the Honda engineers are the best (of the Japanese) when it comes to making high output production NA motors..
Honda S2000. goddamn
B16.. yep, bloody hondas
And as for the Honda bike division... those boys are awesome... how does a 32 Valve V4 (oval pistons) at 21,000 rpm sound? making around 250hp/ltr.. in 1982. (Pity they were competing against two-strokes making 300+hp/ltr..)

Would be very interesting to see what Honda could do in F1 if they dropped the "cylinders must be circular" rule... The one they introduced just after honda announced a return to f1...
as for mass production.. you'll probably find there were more B16s made than 20vs.. B16s were sold worldwide, the 20v only offically got released to Japan and South africa AFAIK.

And yes, the toyota quoted power figures for the 20v are a load of BS.. has anyone here seen over 100kw at the wheels of an internally standard 20v?

[RomanV]

No the reason behind the oval pistons, was that the engine was originally a v8 design.

But a rule change or something disallowed it.

So they basically joined the cylinders into pairs to make it a v4 engine.

IIRC it wasnt very reliable.

[RS13]

Yeah, I've found that although the factory power ratings for B16 and 4AGEs are similar, when strapped to a dyno the Toyota motors have less power than quoted, unlike Hondas!

Driveability, I prefer the 4AGE over the B16A, I've owned/driven plenty of both, while the B16A is good fun taking to redline in each gear, the notchy gearbox and awful cable-actuated clutch really let it down, especially in stop-start traffic. In their defence though, they changed the cable to a hydraulic system, beginning with the last model of the DA6, with the B16A2, I believe..

I also had a brass button in my last VTEC Integra, it was bloody awful to drive, but having driven a few AE92s, AE101s, I really liked the nice, flowing shift mechanism, and smooth, gradual clutch, but I found the powerband just wasn't as fun, or marked as the VTEC's, and didn't really want to rev it out, as it didn't seem to do it with the same ease as the Honda.

makes a superior engine in a disappointing line of cars.

I couldn't agree more with that. When you've chucked a few Integras, Civics around, you can't help but wonder why they couldn't have developed the VTEC motor into a rwd platform! Not to mention the leaky windscreens, the rust, the weak gearboxes..

[soopachargen]

just to keep it on topic... i want the technical advantages the b16 has over a 4age, not opinion, not what makes the most on paper, i want to know why the b16s always make more power than a 4age on the dyno and what makes their heads flow so well, if you had a 4age 16v with the same compression as the b16, making the same revs and used a contol cam and profile.... eg no vtec adjustment would the b16 still be more powerful??
please can i have FACT rather than OPINION.

[RedMist]

No the reason behind the oval pistons, was that the engine was originally a v8 design.

I think you'll find it was an 8 valve in one cylinder. Not a v8, hence they used a oval piston to fit all those bloody valves in... AND TWO RODS PER PISTON!! Honda had reliability problems, and dumped the project.

B16 over 4age. (for performance purposes only, ie not economy)
lets start with VTEC. far superior than VVT, as it adjusts lift and duration. It allows you to run a much more agressive secondary stage cam. Hence more power top end.
Its a sligtly bigger engine. 1587 vs 1595. its only a small increase, however every cc counts.
Valve area. This is where the B16 really pisses on the 4age. The 4age 16 valve has an inlet valve area of 5845mm^2 whereas the B16 is 6842mm^2. Thats a huge 15% increase and the B16 valves arent masked!!! I suspect the 20 valve evens the score... however with 3 inlet valves you have swirl issues.
Exhaust valves are a similar story with a massive 17% more area than the 16 valve 4age
Its a light weight block, compared to the cast block of the 4age.
The rods are longer 132mm as opposed to 123mm for the 4age. It allows the piston to sit at almost TDC for longer. This in theroy is supposed to build more pressure and more power. It also doesnt provide as much side angular thrust on the pistons, as such you can run a smaller piston skirt. Lynn Rodgers played with rod lenght on a silvertop for Alan Buttler. I dont know if they made much of a gain, but I do remember Alan stating that they didnt get much from the engine modifications other than the cam.

You have stated that both engines should use a control cam for your theroretical tests. However the added duration and lift of the VTEC cam is one of the reasons the Honda engine does so well.

Dont get me wrong, there are some issues with the B16 which dont make it the best modified engine. But stock... unfortunately... Honda got us.

[RomanV]

http://en.wikipedia.org/wiki/NR500

By 1979, Honda had decided to return to motorcycle racing. Honda was committed to the four-stroke principle, yet since they'd left bike racing, two-stroke engines came to dominate all classes at the top level. The company felt that a 500cc V8 could compete with the four cylinder 500 two-strokes run at that time, but the rules limited engines to four cylinders. However, the rules said nothing about the shape of the cylinders, so the designers siamesed adjacent cylinders of a V8 together to produce an oval-piston engine. In doing so, they achieved a V4 legal to the rules, but with the valve area of a V8. With two connecting rods per piston, they also got the relatively light per rod loading of a V8. Both of these factors gave a very high-revving engine (the actual figures were never disclosed, but it was known to be over 20,000rpm) for that time. Exact power figures were never released, but the later 750cc endurance version (the NR750) made over 200bhp.

[blackie]

Doesnt the honda use a really efficient pentroof combustion chamber, or does a 4age utilise that also....

[RedMist]

RomanV, nice quote and most websites tend to have that association. I dont dissagree however I think the V8 association is a little loose. The valve area in a oval shaped combustion chamber is massive, far larger than that of what would have been proposed by a V8. The firing order different, the head casting different, the block, the bearing positions, pistons, rods, ... pretty much everything... It may have been taunted as a conjoined V8, and be born from the restrictive rulings as to multi cylinders, but its far from that. In fact, its far better than that, in concept.

A Graham Bell summised (or had inside information) that Honda looked at generating the same (or more) HP than those dominating GP racing with 2 Strokes at that time. The valve area required to generate that type of HP was stupendous and not capable with any 1970's design. The answer was the ingenous oval piston design. It allowed for two rows of very large valves to lie side by side while keeping the cylinder cc's to a bare minimum.

Pity Honda couldnt get ring seal correct. NR500... Not Ready.

[RedMist]

Doesnt the honda use a really efficient pentroof combustion chamber, or does a 4age utilise that also....

All three, the 16 and 20 valve and the B16 all run pentroof combustion chambers.

I have no idea as to why its called pent though. 5?

/edited

adj.
Penned or shut up; closely confined.

[anthonym]

you can't help but wonder why they couldn't have developed the VTEC motor into a rwd platform!

[Grrrrrrr!]

The oval piston idea wasn't shelved till quite a while later... they dropped it from the GP class when they realised they would never get the power to compete with the two strokes, and kept working on it for several years, then entered a 750cc bike at Le Mans in 87, which failed to finish, then in '92 they made a run of hundred and something roadbikes NR750 (RC40)which were sold at horrendous prices. I guess they sorted the ring sealing problems out enough to make a production model(I heard they had 3000 patents on the rings alone).

back on topic ..

B16A 2nd Gen head showing valve area..


anyone got a good pic of a 4age 16v head for comparision, couldn't find a good one on billzilla.com

[RedMist]

You went and forced me to go out to the garage. I only had my cell camera, but you get the general idea. I dont have anywhere to host them, someone want copies of a silvertop, blacktop, bigport and Mitsi 6a10 combustion chamber photos?... to host them!

Still can you spot a 2.5mm diameter difference in a 33mm valve, from a low quality photo?

[strx7]

Comparing the 1989 engines

B16A =160 ps (117.68 kw) / 7600 rpm
15.5 kg*m (152.00 N*m) / 7000 rpm

red top 4AGE
140 ps (102.97 kw) / 7200 rpm
15.0 kg*m (147.10 N*m) / 6000 rpm


Why does it make more power? cause it pulls more RPM.
Torque @ RPM = HP. pretty simply really
Put some longer duration cams into the 4AGE so it too makes peak torque at 7000rpm, and it'll make close to 160 HP.

[Grrrrrrr!]

dont worry bout the 20v ones redmist, plenty of those on billzilla.org, just no decent standard 16v ones.
not sure how visible the difference will be, but the b16 pic shows that you wouldn't get much bigger intake valves into a standard bore.. they take up the full width. in fact it looks like the head is even getting rather wedge shaped due to the size difference between intake and exhaust valves.

[strx7]

has anyone got a dyno sheet of a bog std B16A vs a bog std Black top 20V? I'd almost put money on it that the 20V has more area under the curve becasue.........
The black top makes
165 ps (121.36 kw) / 7800 rpm
16.5 kg*m (161.81 N*m) / 5600 rpm

Now at 5252 rpm torque in Nm and power in HP have to be the same valaue, with peak torque being made at only 5600rpm, i'm picking that its making around 160hp pretty flattly from 5252rpm right thru to 7800rpm, which is a pretty good power range for a 'peaky' 1.6. Also considering that the black top 20V, when on VVTiL is running 292 intake duration with 11.5mm lift. I'd say that it quite possibly would make reasonable power thru to 9 or 9500?

has anyone ever pout a forged bottom end under a black top and turbo'd with with an DECENT aftermarket efi system? i'd be interested to see the results.