black_knight

iTrader: (1)

Compared to best Ford, BMW, and all the other production car motors... YES, it is.

Hah! Exactly, it wasn't! That's my entire point. Pushrods make cars cheap and fast. DOHC makes them slower, heavier, more expensive, and impressive to morons who like HP/L! Man, you just walked right into that one!

distortion_69

iTrader: (20)

Some things never change. This will be argued among ricers everywhere, forever.

Unfortunately since nothing states that the cars have to be the same displacement in America, hp/l is of no importance.

Josh

engineermike

Benchmarking, benchmarking, benchmarking!!! It took me about 8 pages to finally convince black_knight that hp/liter has a use and I'm not about to start over with you.

ONCE AGAIN, when you compare completely different types of engines, in completely different cars, built for different purposes, you can't compare the mileage. When you compare the same car with the same engines of 2 different displacements, you see that the smaller motor will get better mileage.

With enough gear it will!!! Archimedes said, "Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." Though, with only 170 hp, the ZX10 motor won't push the 140,000 lb tank. . . That's where the 1500 hp (though, at 50,000 rpm) comes in handy.

Mike

engineermike

Not at all. I admit that hp/liter, hp/lb, or just plain hp, was not the highest priority when BMW designed the 4.2 v-8.

Yea I could see that conversation. . .

Engine designer A, "Hey, how much hp do you think we could get out of the LSx architechture?"
Engine designer B, "I dunno, let's just build one and dyno it."

Riiiiight. . .

. . . or speculations of what adding different valvetrain, cylinder head, or intake manifold configurations might do to a motor. Bingo!

If you think that "more power and less weight" are the only things that make an engine better, then you have much to learn.

The do it because they want to make more power. ONCE AGAIN, if DOHC suddenly were allowed in NASCAR, how long do you think it would take before ALL teams switched over to it? Why? Because it makes more power! (dare I say, for a given displacement).

. . . and more hp than the LS6 (both versions). . . and the L92. . . and the L76. . . and the LS2. . . and the L98. . . and the LS4. In fact, coming in at 4.2 liters with designed weighted toward NVH, in it's first year of production, the BMW v-8 out-powers all variants of the LS engine except for the part-Titanium performance-car-only LS7. The LS3 squeeked by, but it isn't even in production yet.

You can point that out all you want. I like driving around vehicles with alot of torque. I never said it wasn't fun. But there are some v-6 comp eliminator cars that can hand it to me with 1/3 to 1/2 the torque. . .

You're right, physics doesn't apply to the LS1.

Oh wait. . . the 7.0 gets worse mileage than the 6.0. (once again. . .)

ONCE AGAIN, you can shorten the 1st few gears to make up for lack of peak torque, then make the top gears taller to get the mileage (is this FACT just not sinking in?).

ONCE AGAIN, 2 different cars built for 2 different purposes. If you want to see the effects on gas mileage of varying displacement, then don't change the whole friggin' vehicle. (a la 5.4 vs. 4.6, 6.0 vs. 7.0)

Not if you increase hp/liter!!! I mean, hey, bikes are smaller with smaller motors. My ZX-10 gets 45 mpg! And it's a real turd, running 9's at 148 mph.

Smaller motor, smaller vehicle, higher hp/liter. . . the result: fast and good mileage.

Really? You can't possibly get more than 420 hp out of the BMW DOHC v-8? No, you can't go down to Thunder Racing and buy a TRex cam for it. But, there is way more hp potential in the 4 valve v-8 I assure you.

[QUOTE=black_knight]Oh, lord. The 5.0 aftermarket is way better than the 4.6 aftermarket. [QUOTE=black_knight]

Hey, when you can make 800 rwhp with stock heads and cams, why would anyone make an aftermarket head? In fact, it's a rare heads/cam/boosted 5.0 that gets 800 rwhp. Hell, it's a rare heads/cam LSx that makes over 800 rwhp with boost!

If you compare the LS1 to the 2v truck version, then the LS1 does mop the floor with it. If you compare the LS1 to the latest version of the 4.6, then it does not. Besides, shouldn't we be comparing the LS1 to, at least, the 5.4 4v motor? Anyway, once again. . . the Ford mod motor is an engine versatile enough to make 190 hp in a pickup, 215, 265, 320, then 380 hp in a mustang - capable of over 800 rwhp without pulling a valve cover. And cheap to produce also. If you think that's "missing the boat", then you can't be helped.

Pushrods do make engines cheap. You really need to let go of the premise that DOHC makes engine heavier and slower, because they wouldn't use them in all forms of racing where they are allowed, and motorcycles (where weights, size, and performance are highly competitive among brands) if that was true.

You guys are really starting to bore me. If you don't have anything new to bring up, I'm about just let you watch the industry change so you can see for yourselves. These 4 truths still stand:

1. Government mandates and fuel prices are creating the need to increase fuel mileage.
2. When compared on an even playing field, smaller motors get better gas mileage than larger ones (a la LS7 versus LS2 Vette, or 5.4 versus 4.6 Expedition).
3. Despite our difference, we all agree that we'll want fast cars into the foreseeable future.
4. Any deficit in torque can be overcome with gear.

These 4 realities can only lead one place: smaller motors with greater specific hp.


Mike

germeezy1

Wrong any deficit in torque can be overcome with a combo of extreme light weight and gearing. Go drive an S2000 and an RX-8 those cars have great gearing...gearing in fact where you keep looking to shift up on the freeway.

I still stand by the fact that light weight is the only true way to overcome no torque.

FieroZ34

iTrader: (1)

BY the way, the new BMW M3's V8 is a 4.0l, not a 4.2. It is basically the same as the 5.0 V10, without the last two cylinders (Think the 4.3 of the 5.7).

Remember kids. I drive a DOHC swapped Fiero because I want it to be slower, heavier, more expensive, and to impress people with it's hp/l. Not because it, in reality, weighs less than the factory 2.8l OHV V6, makes over 100hp more, makes more torque from idle to redline, revs 1500rpm higher, gets significantly better gas mileage, sounds better, and is more reliable. And what has it cost me for all of these benefits, since surely it must be expensive since it's DOHC? Well, $1000 for a brand new GM crate engine, and $600 of eBay shopping to get the manifolds and accessories. $1600. Wow, I think I'm going bankrupt. *rollseyes*

Louie83

iTrader: (3)

Well good then, because I was starting to get that idea that you saw no benefit for OHV's in any situation.

And I think the point that Black_Knight is trying to get across is pretty similar to my above post. Obviously, both platforms have advantages and disadvantages...so why are you guys going in circles arguing again?

JD_AMG

Compared to other 500hp engines(Like BMWs or MBs), yes its light and small.


And Im saying that's not right. Generally engines have gotten more displacement since the 80s. Look at all the performance cars, how many of them gone down in displacement?
[BMW 4.0L V8]
Not according to BMW, who havent stopped trying to brag about it "being the lightest V8, weighing in at 425lbs." While ironically the LS2 weighs >390lbs...

JD_AMG

I guess the bigger cam(s) dont effect gas milage either...
And for the vette, the significantly larger wheels/tires, and beefed up drivetrain of course dont play a role in gas milage.

JD_AMG

Good thing your not trying to compare an engine from the 80s not really built for performance to a modern day performance engine... You need to read between the lines. If you were to put OHCs on that original OHV engine, it would become bigger, and heavier.

FieroZ34

iTrader: (1)

I compared an engine made in 1988 to one in 1991. I wasn't aware 3 years was the difference between ancient and "modern day." Both use the same engine block, just the 3.4 has a slightly larger bore/stroke. That is exactly what GM did, they put the OHCs on a pushrod block. And what did it do? Everything I stated, including a drop of 40lbs.

dakkrin

well you're doing great proving gearing is important, but thats not an issues, everyone knows that

lets say i go to the dealership to buy a performance car,
all cars are identical price etc, except
car A has an engine producing 200 hp/l
car B has an engine producing 72 hp/l
the uneducated buyer will automatically take the 200hp/l
the educated will do more research and realize car A is a 1L engine and car B is a 7L engine
both cars weigh the same and get the same mpg
now which one is better, this is an exaggerated hypothetical example but you see how hp/l means nothing
the moment you change the gears you realize that

great arguements though, makes you think about what you really want to buy

black_knight

iTrader: (1)

Whoa, wait a minute. I can guarantee you that hp/L WAS one of their goals. That's why it sucks so much.

Not so much there. But we've already had this conversation. I've told you what constitutes misusing HP/L. This thread started with a misuse of HP/L, which I quoted. And you continue to advocate misusing it.

Of course not! I am only saying that HP/L is not one of those things!

Yes, exactly, you thick-headed lunatic! NASCAR IS DISPLACEMENT LIMITED!

The BMW is also performance-car only and limited production. I am comparing like to like. And I'd bet money that the BMW is more expensive.

Neither is the BMW! They will be coming out at the same time! Being outpowered by the LS3 is an even bigger embarrassment, given it is cheaper and mass produced!

I am providing examples where we do what YOU insist is possible, which is having a low displacement motor that makes EQUAL hp and less TQ and is geared to go just as fast. All of the counter-examples you gave ('vettes, fords) do not meet that criteria. It is YOU who are giving bad examples!

No, I just await your proof.

Oh, like the BMW vs the LS7?

You mean, higher hp/pound. HP/L does not make cars go faster.

If you think that the BMW v8 is more moddable than the LS7, then you are simply a fool. And there will be no convincing you. The LS7 is better and you can mod them both to the max, but the LS7 will still be better.

Do you care to point to what the hell you are talking about? Do you mean the IRON BLOCK, FORGED terminator motor?

Keep it N/A. Then tell me that a ford 4.6 liter does not get its *** handed to it by the LS1. I dare you.

No, actually since the ford 4.6 is heavier and larger then the comparison isn't fair to the LS1. And that's before bringing the even larger ford 5.4 into it! If you're going to use contemporary Fords, then you'd better use contemporary LS motors - i.e. the LS3. What I will remind you is that you are arguing against the statement: Ford dropped the ball with the 4.6. Compare any version of the 4.6 with its contemporary LS motor and tell me the Ford doesn't get its *** handed to it.

Do you have a reading disability? DISPLACEMENT-LIMITED RACING!

What applies to motorcycles does not scale up to cars.

No doubt this will make cars suck. And since DOHC sucks, then there you go.

I've been over how your examples do not prove your claim: that having a low displacement motor that makes EQUAL hp and less TQ and is geared to go just as fast will make better MPG.

At the expense of? Oh, right, #1.

So you'll win by government mandate? You OHC people sure like "winning" because you force the rules to favor you, like in displacement-limited racing...

None of that will change the fact that pushrods can make a superior street motor.

distortion_69

iTrader: (20)

You have more hp/l, but an ls1 in the same car would assrape you.

Which leads us back to it doesn't matter, unless you are forced to use the same sized engine for some reason.

Peace,
Josh

black_knight

iTrader: (1)

Exactly! It's just that the advantages of pushrods are often more suited to the real world and ohc is more suited to displacement-limited racing.

FieroZ34

iTrader: (1)

Well, it might. Until it puts the transmission into the pavement.

And look at the cost. I got a brand new crate engine for $1000. You can't even buy a used 60k LS1 for that. And now you need a $1200 adapter, you have to build custom headers, you have to rebuild the entire engine cradle, you need custom axles, you need to find a way to make the PCM work (Good luck, most just use a standalone), and God knows what else.

Instead I'll spend $2000 on a premium air:liquid intercooled dual ball bearing turbocharger, boost it to 10psi, and make 100+ more whp than the LS1, at a fraction of the price.

Oh yah, forgot, you also need to notch the wheel well and frame section for the LS1.

And you need an electric water pump, and you can't have A/C.

black_knight

iTrader: (1)

Nobody's criticizing your choice. I'm just saying that pushrod engines, when you're not dealing with the junker your car came with, can do some good things and shouldn't be dismissed. I just don't see OHC as being the winner right now. With new technology, that might change some day; who knows. But this whole "inevitably, OHC will replace it" and "pushrods are old tech, maxed out and soon to go" stuff is horse hockey.

FieroZ34

iTrader: (1)

I don't care if you do criticize my choice. Frankly, I'd like to see you try. I'm absolutely positive I can prove that any other engine you suggest is inferior overall in the categories of cost, weight, power, and ease of swap.

Furthermore, I didn't post that to say "Well this was the best engine for my car so it's the best ev3r." My engine would be a pitiful engine for a Formula One car, and a pitiful engine for an F-body (Unless the F-body was older than 1998 of course ) I posted because, quite simply, you made a very incorrect, ignorant, and blatantly stupid remark that DOHC engines are solely to impress people by their hp/l. If that was true, it'd be in my sig that my car makes more hp/l than any car or motorcycle on this board. And if I don't, then doing so is a turn of the **** away.

black_knight

iTrader: (1)

BMW's seem to be. And for many OHC engines, that is the case. I didn't say that every single set of pushrod heads on the planet was superior to every single OHC set. I said that pushrods offer a better street setup and OHC was more suitable to displacement-limited racing and impressing HP/L morons - as a rule of thumb. A quick look around at production V8's vs LS series will confirm this.

I'm sorry if I offended your little V6. When compared to the particular set of crap *** heads you had in there, yes you improved it. You started with really crappy heads and so a set of slightly less crappy dohc ones improved it. That says nothing of significance about pushrods vs OHC.

To prove me wrong, you would have to be claiming that your old heads were the best pushrod tech that GM can do. I don't think you're stupid enough to claim that.

FieroZ34

iTrader: (1)

Or maybe they're built like that for the power curve? Not everyone likes the instantaneous torque of the LSX. I like it, but I also really enjoy the DOHC power curve. It has plenty of low end, but changes to a completely different style up high. Not to say I don't like the LSX, but I really enjoyed driving the M5 as well. Different strokes for different folks. In my application, and it applies to a lot of applications, the DOHC setup is superior. There's a reason Toyota sells more cars than GM, and doesn't make a single pushrod OHV engine. I'll agree pushrod engines have their place, and I really enjoy our LS1, but to say they are better at such a broad scheme of things is wrong, as is saying DOHC is solely for HP/L. A better street setup? Bullsh!t. Find me a single pushrod engine that will make for a better street setup than my "little V6." Remember the transmission needs to stay put and be operation, and the engine has to fit, and it can't require welding in a F-body frame in order for it to fit. Better street setup for the F-body? I'll agree.

Slightly less crappy? My heads flow more than LS7 heads at any lift, and they haven't seen a CNC machine (And we all know how cheap CNC machines are...)

The 2.8l heads suck, no doubt about that. But to prove me wrong, you have to find a pushrod set of heads, that are on a motor that will fit my previously stated conditions, that are better. And I'm doubting you will if the best cylinder heads GM has EVER made don't cut it.

Trust me, you aren't going to win this segment of the argument. I did the research to find out which motor was THE BEST for my application, so I wouldn't be disappointed in the end. So I'll do your part for you, the top pushrod choice was the 3800 Series II S/C. Now you have to tell me why this is better than what I now have. It isn't, that's why I don't have it.