Pushrod or OHC

[Slicks]

Originally Posted by Matra et Alpine

PS: the car park at Zolder - over 600 Alpines present

Thats awesome!

[Slicks]

Originally Posted by Matra et Alpine

I was comapring an engine with an output for a given volume of space it used up.

Yes, for a 6 cylinder racing engine to a 8 cylinder street engine.
Again, not like to like.

YOU are the one that prefers that over hp/l
NAD I DID POINT OUT that the engine was a modern performacne version of an older design adn that it was oirignally capable of 250bhp and now 400 with no major changes - certainly NOT to the level of the SODEMO engine.
At least you are now aware of smaller engiens with COMPARABLE output and YES I had to "play a trick" with a race engine to get you to read.
BUT in the past you don't read things others say and DEMAND proff. I coudlnt'have said my A610 engine is smaller than the LS1 as you'd have said I was lying and so I chanced upon theat engine with dimensinos and posted it.

I know there are (phyiscally) smaller engines than the LS1 that make more power, but their doing so with either turbos, or high revs. And none will cost as little as an LS1.
Sorry I dont believe everything someone says over an interent forum. But proof is nice.

Funny as most of your concepts of what is involved in engines dates from then

Really like what?

Clearly you didnt' engage brain before letting the fingers loose on the keyboard
IF you only want to compare like with like, then WHY were you comparing with an I4 ?

To show you guys that the "old tech big ass" pushrod engine is not a tank. That it is comparable in size to a 1.6L I4. To try and make you guys understand, "oh wow, so thats why GM is sticking to pushrods, its making 400hp, and 400ft-lbs of torque from the size of a miata's engine, while still remaining inexpencive."

It's the preposterous stance you take on the LS1 and it's size by ONLY comparing it against a known large cast block and NOT taking on-board that there are other alternatives.

Thats a load, I'd compare it to any block, and you see, it took this long for you to find an engine smaller with comparable power.

Others do, I've already acknowledged the benefits of the LS1 and others you've posted. Unliek others - see Culver - you seem incapable of actually absorbing, considering and responding.
YOU only seem to knee-jerk and repeat the same twaddle

And you already know the benifits to the V6 you posted, so I pointed you the down sides, and corrected the LS1 dimensions. And you know as well as I do that if that V6 were to use OHV that the heads would be physically smaller, theres no getting around that.

So here was presented an OHC engine which is smaller than the LS1 and lighter. YOU seem to be the only person envountered who thinks the LS1 is the smallest goign. I think maybe you've been sitting to close to the exhuast funes

Repeat of what I said earlier, I KNOW there are smaller designs out there. But I have yet to see something close to a 5.7L V8 that is smaller.

Tell me why and we can discuss.
Tell me WHAT on a street engine MUST be bigger than on a race engine ?

Usually racing teams make the engine as small and light as possible (of course taking in account durability etc.) Do you have dimensions for the street engines?

[Matra et Alpine]

Originally Posted by Slicks

Yes, for a 6 cylinder racing engine to a 8 cylinder street engine.
Again, not like to like.

a;ready pointed out it shares components adnd knew you'd not accept my "say' on engine size

I know there are (phyiscally) smaller engines than the LS1 that make more power, but their doing so with either turbos, or high revs. And none will cost as little as an LS1.

Volume makes a big difference, BUT why does it matter if it uses turbos or revs ?
IF it makes the power in the space and has the service intervals then it shoulnd' matter - UNLESS trygin to make somthing look "best".

Sorry I dont believe everything someone says over an interent forum. But proof is nice.

and very hard to come by. It was a chance discovery of those dimensions as I was following up a lead for upgrade of my own engine.
Nobody else goes aroudn making claims about an engine based on it's volume. I now realize that hp/ft^3 is the redneck equivalnet of the rivers hp/l

Really like what?

Using revs, gear changes, speeds, handling, roll, comfort ..... :falls asleep:

To show you guys that the "old tech big ass" pushrod engine is not a tank. That it is comparable in size to a 1.6L I4. To try and make you guys understand, "oh wow, so thats why GM is sticking to pushrods, its making 400hp, and 400ft-lbs of torque from the size of a miata's engine, while still remaining inexpencive."

But you see you only keep referencing the ONE picture
Nobody ever said it was a "tank" of an engine.
SOME of us know how small an engine CAN be, you want to see the Powertec engine Or the Honda GP engine, or the LS1.
It's the LACK of comparison with other engines that belittles your POV

Thats a load, I'd compare it to any block, and you see, it took this long for you to find an engine smaller with comparable power.

Let's see, you are judging the difficulty of finding evidence based on the assupmtion that a person is spending all their time to 'rpvoe' somethgin to you when they already KNWO it but just know they dont' have the type of evidence you'll accept.
Grow up, Slicks, I dont' play that game with you any more. I spent a fair bit of time on you in the past presenting solid evidence for it to be requested to be further proved etc. So the fact is you don't accept ANY evidence that is at odds with your opinion and so we dont' waste our time searching.
i pointed out AT THE TIME how I came across those sizes

Repeat of what I said earlier, I KNOW there are smaller designs out there. But I have yet to see something close to a 5.7L V8 that is smaller.

Ah, now the litre capcity comes into it as well.
What is it that REALLY matters, coz now we're confused
Is it the power in the space taken up by the engine.
Is it the number of cylinders.
Is it the capacity.
coz so far you've put them all in the pot, so in reality you're asking which other 5.7l V8 engine is smaller. Yep you got us there as there's only the one 5.7l engine I know of in production Self-fulfilling proof now

Usually racing teams make the engine as small and light as possible (of course taking in account durability etc.)

In reality race engines are often STRONGER than road engines.
Please answer the question.

Do you have dimensions for the street engines?

Go back and read the posts, I've given you the ESTIMATES for the numbers.
I only posted the original pic to provide you with some facts and GAVE the provisos as we went along.
Tell you what, if I get under the car with a video camera and a tape measure THEN will you STFU ??
Time for me to turn on the ignore again

[jcp123]

I guess from my point of view, I have OHV, and it works, so why change what works. I'd have a helluva time fitting an OHC or DOHC engine in my car even if I wanted to, anyway.

I do also have a soft spot for flatheads, too...talk about old-school

[henk4]

Originally Posted by jcp123

I guess from my point of view, I have OHV, and it works, so why change what works. I'd have a helluva time fitting an OHC or DOHC engine in my car even if I wanted to, anyway.

I do also have a soft spot for flatheads, too...talk about old-school

Friction dampers work, leaf springs work, carburettors work, and even 6 volt cars were known for being able to ride.
Why not start a debate about crossplies versus radial tires?

[jcp123]

Funny you should mention that...I have carbs and leaf springs too! No complaints, although I wouldn't mind having coils.

Not that I have anything against OHC (I used to, heavily until pretty recently). I have seen too many SOHC and DOHC european sportscars and Mercedes lately that I would love to have for me to still hold a negative opinion about them. But I really also think that bagging on OHV's is stupid. It's solidly reliable, compact, and still the type that I'm most familiar with. Each has its place.

All I ask is that whatever I drive NOT be computer-controlled, and I think that that's my main point these days where I am not willing to compromise.

I don't believe in progress for progress's sake. Sometimes we need to slow down and remember what driving a car is really all about. This goes for me in general too. I wrote my last paper by hand because while I could have done it more conveniently and quickly on the computer, there's something very striking about writing it by hand. Obviously, putting a fine pen to the paper (I am also something of a pen collector, my current fling is my Parker 51 ), and feeling it flow over the paper is a vastly different sensation from typing. It forces a higher level of perfection, since pen is not readily eraseable, and also makes you think about each word you put down. And when you're sone, you get an extra sense of accomplishment. Either way gets it done, but one way gives you a more personal connection to what you're doing, and also keeps me from blindly following the nameless faceless crowds of pop consumer culture.

My point is, I think the way I do in terms of a whole lifestyle rather than just cars, which obviously is a part of it. I do it deliberately because it's not necessarily the most efficient way of doing something, nor the most practical, fastest, etc. I like it that way.

[Slicks]

Originally Posted by henk4

, leaf springs work

Leafs do work. And like you have room to talk about springs, minis use little rubber bumper things...

Here:

"Design Synthesis of Suspension Architecture for the 1997 Chevrolet Corvette
The first C5 suspension concepts were conventional coil over shock absorber for both front and rear suspension. One proposal utilized a horizontal coil over shock actuated by a bell crank upper control arm, and was evaluated in a mule vehicle.
A composite transverse leaf spring was selected for efficient packaging and low overall mass. Shock towers may be lower and smaller for hood height and less intrusion in the engine compartment. The shock absorber may be placed further outboard on the lower control arm than is possible with a coil over shock unit. The improved shock lever arm ratio provides efficient damping authority and reduced jounce bumper loads (the jounce bumper is integral with the shock absorber.)
Three basic spring configurations were considered: transverse leaf, coil over shock, and seperate coil. Attachment was considered either to the knuckle or to a lower arm/link. Following the decision to attach the spring and shock absorber to the lower control arm, the composite transverse leaf emerged as the best alternative, permitting the best shock travel ratio, lowest mass and the smallest shock tower which contributed to the improved trunk volume."

In testing for earlier Corvettes, GM testing showed that coil springs fatigued at a much greater rate than composite leafs. They mentioned their suspension testing equipment of the time showed coils were rated in 100's of thousands of miles, while similar fatigue for composite leafs was measured in millions of miles. On top of that, leaf springs can spread their load over a wider surface, and when used like a modern Corvette (transversely), there's some inherent benefit in roll stiffness. If you don't have a Corvette, you won't have this benefit, but the others remain (lower weight, lower unsprung mass, corrosion resistance, fatigue resistance, etc.).

Got that of off supercars.net

[henk4]

Originally Posted by Slicks

Leafs do work. And like you have room to talk about springs, minis use little rubber bumper things...

That is what I said that leafs work, and I know about how the mini works

[ruim20]

isn't There a direct rival to the LS1? i was thinking about the Toyota/Lexus v8 or similar, does the GM v8 differ so much in size from the other v8s in the market?

[jediali]

Originally Posted by Juggs

the problem with 2 valves is as the bigger the valve gets the less velocity you get from the incoming air. if you dont have a lot of velocity it doesnt matter how much air your getting in there. with something like a 4 valve design you can suck up as much air as a big 2 valve design but still have good velocity since you have 2 small openings as opposed to 2 big ones. its like you were breathing thru a big straw....you could blow out easy but the air coming out wouldnt be moving very fast. now blow thru a small straw..it'll be harder to blow thru but the air coming out will be coming out fast. now you use 2 small straws and you can move the air out easy and it will be coming out fast. see what i mean?

I agree pretty much too, i like the straw analogy. So basically if an engine can move air/fuel/exhaust through the block as easily as possible with min. friction from valvetrain then we are doing well. The idea that more valves are used in order to establish as much flow area as possible through optimized lift is the way to analyse it IMO. Due to fluid boundary layer seperation (fluid dynamics) it is possible to have too much valve lift but essentially each valve creates a cylindrical flow path which requires valve diamater and lift to calculate (A=pi*d*L). An optimisation calculation would establish for any number of valves and a given lift just what combination meets flow criteria. Combustion chamber design and q=Av stuff would be next on the todo list.

Note that sometimes at lower revs such high flow head capacities can limit volumetric efficiency simply because when the piston starts to rise it pushes air/fuel mixture back up intake passage to easily, therefore port deactivation, variable intakes (and pretty much all variable techs) etc insure intake gas inertia allows better cylinder filling specific to operating point of engine.

Originally Posted by Matra et Alpine

There is a formula that equates the valve lift to the valve size and the optimum.

"an introduction to engines" by John lumley covers this sort of stuff really well

Originally Posted by Matra et Alpine

I DO remember that some companies ( Toyota was one ) that played with 5 valves as it gave less null-spots in the chamber but they didnt' get taken up much as I'm sure the cams woudl ahve been a nightmare to squeeze in to the availabel space.

Originally Posted by henk4

Audi introduced 5-valve heads and the 4 pot 1.8 turbo engine used in a lot of Volkswagen based products is still dubbed 20V.

both VAG/audi (1.8,1.8t,v6,v8) and ferrari (F355,360) have dropped their 5vpc designs in favour of 4vpc. I think the extra friction and moving valvetrain mass let the side down (still not as heavy and inertia laden as pushrods - sorry slicks!).

Originally Posted by ruim20

isn't There a direct rival to the LS1? i was thinking about the Toyota/Lexus v8 or similar, does the GM v8 differ so much in size from the other v8s in the market?

think of mercs new V8, 6.3 litres yet very light + efficient and combines character of high revving power and low end tractibility. This engine is oversquare (like ls1 i believe) and was designed by a clever brit who rejuvenated merc's pterol engine range since the old 3vpc v6's/v8's

[2ndclasscitizen]

Originally Posted by jediali

both VAG/audi (1.8,1.8t,v6,v8) and ferrari (F355,360) have dropped their 5vpc designs in favour of 4vpc. I think the extra friction and moving valvetrain mass let the side down (still not as heavy and inertia laden as pushrods - sorry slicks!).

As has Yamaha with great success.

[Slicks]

Originally Posted by ruim20

isn't There a direct rival to the LS1? i was thinking about the Toyota/Lexus v8 or similar, does the GM v8 differ so much in size from the other v8s in the market?

Not within its price range. The 1UZ is supposedly around the same weight, but physically bigger, and doesn't have the N/A power potential that the LS1 does.
Check out the huge conversion forum on LS1tech (just one of the many LSx conversion forums on the net):
Conversions & Hybrids - LS1TECH
You can get lot of info and pics here for comparison.

EDIT: FWIW the LS1 is also smaller than many V6s, for example the Nissan VQ in the 350Z.

[clutch-monkey]

Originally Posted by Slicks

Not within its price range. The 2JZ is supposedly around the same weight, but physically bigger, and doesn't have the N/A power potential that the LS1 does.

are you sure? lexus V8's can be picked up for cheap (not represantative of actual build cost, i know) and i figured 2JZ's would be around the same wieght as an RB (much heavier than an lsX)?

[Slicks]

Originally Posted by clutch-monkey

are you sure? lexus V8's can be picked up for cheap (not represantative of actual build cost, i know) and i figured 2JZ's would be around the same wieght as an RB (much heavier than an lsX)?

^ sorry meant 1uz.

[clutch-monkey]

ah rightio. i hear they're pretty bulletproof, and i kno wthey're cheap to pick up around here but seems like no-one developed any aftermarket bits for it