diambo4life

I wasn't exactly sure of the source. I just know that it has the K20 head and K24 block. So you're right. I can never get all those Honda motors inline but as I said, there's a local running loooow 11's in one. It dynoed high 200's in his car awhile ago when he was trapping in the teens, it's probably over 300whp now. Yes! NA. In a car that weighs close to 2200lbs ( + driver ,) it will scoot!

zigroid

iTrader: (22)

what good does it do though? it is meaningless. if you want a good "efficiency" equation go look at torque output per liter.

you know, for the most part whatever you say is true but sometimes you come out with bullshit statements like this. I want to see you prove this. seriously. an intake port is an intake port. sure a dohc setup may not need as much cam lift due to valve curtain area and such but there was never a rule stating that DOHC will always have a higher power potential. thats just ridiculous.

GM's 4.8L truck engine makes 295hp, ford's last 4.6L dohc car engines make 320 hp. one runs on 87 octane. your theory about DOHC is not true.

the last three quotes were stupid, this is just retarded. what kind of forced induction are you talking about? if you stick a supercharger that is limited to 500 hp on both an LS1 and a 4.6L it will only produce 500 hp. there is no getting around this. if you stick a turbocharger that can only flow 800 hp you're going to top out at about 800 hp on both engines. your argument is flawed. the engines making similar power has nothing to do with how many valves it has or where the cam(s) is/are located. it will only produce as much horsepower as the amount of air being fed to it will allow. you are also severely wrong about pump fuel. a 4.6L producing the same hp as a 5.7L engine will have more cylinder pressure. it will get to a point where the 4.6L will require a higher octane race fuel and the LS1 will still be happy with 93 pump gas. once again, your theory is wrong.

carry on.

300bhp/ton

In many respect they are the same thing.

HP = torque x rpm / 5252

So you can not have one without the other, however more often than not making less torque at higher rpm will result in more HP than making lots of torque at low rpm. Hence diesels are often torque monsters, but with comparitively low HP

On an equal basis multivalve engines will ALWAYS have greater potential. There are some multivalve OHV engines, but they suffer the problem of much more complex and less efficent valve train, this ultimatley limits the rpm range which can safley and reliable be used.

The only remaining option to run multivalve engines is to use a DOHC design. Ferrari V8's use 5 valves per cylinder and as a production engine are capable of producing 115bhp/litre or 493bhp from only 4.3 litres.

And YES I know you'll chime in and say a C6 z06 produces more, but it's also using 2.7 litres more displacement to achieve it. Imagine if Ferrari designed a V8 with 7.0 litres displacement at 115bhp/litre it would produce 805bhp. Pretty impressive. And this would still be FULL emissions and noise LEGAL for a PRODUCTION engine while retaining the durability and reliability required for such an engine.

The LS7 stands very little chance of producing this level of HP and remaining streetable. Plus it would not stand a chance in hell of passing emission and noise regs even for an annual check let alone for production.

More proof is the TVR V12, this was a DOHC V12 with 7.7 litres capacity, the production variant produced 880bhp!!!!

Now don't get me wrong, I personally like OHV's for street use and the noise they make. But my personal preference doesn't alter the physics behind it.

I mean I like burgurs, but just because I like them doesn't make them the greatest food on the planet does it?

Not quite sure what you are trying to prove here. The SMALLER OHC engine is producing more HP than the LARGER OHV engine. 100% what I've been saying.

And the Ford unit is NOT the pinnicle of OHC technology and should NEVER be used as such.

I'll make it simple for you, show me at least TWO OHV production engines that make 100bhp/litre in stock trim. Displacement and total HP are unimportant in this instance, just specific output.

Having just read the rest of your post I not 100% sure you understand FI.

Providing the engine is physically strong enough (rods, pistons, etc.) the limiting factor is going to be detonation. The higher the octane the less conbustability the fuel is and thus less chance of detonation, hence more boost/power can be acheived with higher octane.

So detonation is the defining limit for use on pump fuel.

Why? I said the 4.6 DOHC engine has more potential, limiting the blower spec proves nothing.

Yes turbocharging is what I meant. Now a TT DOHC 4.6 Ford Modular motor will be capable of making 700+rwhp on pump. A 346ci LS1 with TT's will not likely see any more HP on pump fuel. Thus making them very even in the HP battle even though one is 1.1 litres short on capcity. From this point on, the only real way to achieve more power on pump fuel is to increase the displacement of BOTH engines.

It has everything to do with it. The valve train and setup is a vital piece of any engine.

Hence Formula 1 cars are capable of revving to 19,500rpm. REMEMBER HP is an expression of torque at speed, so this is a critical factor where making power is concerned.

If this is the case how come older engines make less power.

LT1 5.7 V8 with 9psi of boost will produce less power than a LS1 5.7 V8 with 9psi of boost assuming all other variables are equal?

Why?

It's because in this case the latter OHV design is far more efficent.

Multivalve engines are more efficent again (NOT all of them, but they have the potential).

There really is a lot of info on this and some really good threads in the Adv tech forum with posts from people far cleverer than me.

Also, if you are so against multivalve engines, why have so many OHV's been converted for race use to OHC setups?

The famed Ford 427 Cammer! This was a regular OHV engine which Ford converted to OHC for competition use and was banned because it was too powerful. Why would Ford do this if it was of no help?

The Rover V8 (aka Buick215) was converted by Cooper in the 60's to OHC and used in F1 where it was very successful. Why would they bother if it makes no odds?

Why? psi is a measure of resistance. So 14psi is 14psi the cfm may be different but then it's not the same thing.

Ok then, PLEASE PLEASE PLEASE show me an ultimate 346ci LS1 running pump fuel that in that state can make over 800rwhp reliably?

I'm not saying its impossible but it will be pushing the limits.

ss1129

iTrader: (16)

Wouldnt dumping in a bigger cam equal out dohc? So it seems it would be the choice of the manufacturer on hp. I mean look at the late 80's chevrolet v8s. 305 was like 240hp and the 350 was at about 270hp. By todays standards its a joke. Throw in a bigger cam...add some compression and presto 320 hp. Im not dazzled by dohc. Im not saying its junk or stupid...just not my thing.

Oh and ask any monkey in the world about hp per liter and they will tell you its an import thing. I cant remember the last time I was watching any car show and they were amazed by the hp per liter. Its awful funny how its always mentioned by import peeps only.

Did you ever hear a domestic guy say "man my car made 452 hp at the crank...ummm thats....xxx hp per liter. NO...you know why? Cause its stupid.

mattraypharbor

iTrader: (2)

so guys whats the best way of turning my car into a ricer......??
A nice wing or wut? mabey some neons
















lolj/k

Tainted

iTrader: (9)

I can see where bhp per liter can come into some play, but using it as an excuse is still dumb as ****

brad8266

iTrader: (23)

yes yes my neanderthal mentality compared to your sophisticated intellectual self. Youre a clown man.

Yeah only me and every other American. Well YOU and every other Brit have fucked up teeth.

Once again man, get off my nutz already

uno

hp/liter is a "cool" argument. But in the end 1.8 liter 200hp Integra type r at 111.1~ hp/liter still gets smoked by a 5.7 liter 300hp ls1 fbody which has 52.63 hp/liter. So in the end hp/liter doesn't matter in the street racing forum

gmpower

iTrader: (-1)

That car was moving.

slick1851

My god on on fucken HONDA-TECH.COM and go into all motor part of the forum and you willl learn somthing....


K motors with cams will make over 240whp-260whp

Head work etc will net you more


and race motors over well over 320whp NA all motor



Its a very badass motor, and makes alot of power and can I say it acatally makes TQ

Im done, I gave you some info now you can learn the rest, be the way OEM there is the 2.4, and 2.0

You can pick up 2.6 stroker kits for those motors


later

Sparetire

mmmm. Crow

GMmexican

iTrader: (7)

yeah but the GM ls7 costs less that the ferrari motor and it gets good mileage, thats why most ferraris get hit with the gas guzzler tax and the ls7 doesnt

zigroid

iTrader: (22)

I know what the equation for horsepower is. I just don't understand anyone's obsession with hp/L. it is meaningless. one could say a 300 hp nissan VQ35DE or whatever would be better in an f-body instead of a 300 hp LS1 simply because the nissan V6 makes 85.7 hp/L and the LS1 makes 52.63 hp/L. we all know what the nissan V6s do in a car that weighs about the same as an f-body and even has better gearing. its not as fast in a straight line. therefor, hp/L means nothing. yes, NOTHING. you understand that now?

Im sorry but you're going to have to explain on an equal basis to me because you're making no sense. all the engine cares about is how much air reaches the cylinder. this determines power. it doesn't care if it has 2 valves, 4 valves, or 12 1/2 valves. how is one timing chain more complex than the rats nest of timing chains a DOHC V8 has? one cam is alot more complex than 4! please. how about this. a pushrod engine makes more power per camshaft than a dohc engine. prove me wrong there.

its funny that that V8 that makes 115bhp/liter gets run down by a V8 making a disappointing 72hp/L.

you're right, 805 hp out of 7 liters is pretty impressive. maybe you should go tell ferrari to add 2.7 liters. while you're at it ask them why the Z06 beats up on the F430 pretty good with inferior technology (even though it has a more complex valvetrain.) hey I bet you if honda made a 7.0L inline 4 with the same hp/L of their S2000 it would make 840 hp too. you know what else? if "ifs" and "buts" were candy and nuts we'd all have a wonderful christmas.

a 7.7L V12 will make more power than a 7.7L V8, all else being equal. of course its hard to be equal when one engine has 4 more cylinders than the other. do you think the sole reason that the TVR V12 made more power was because it had DOHC?

I also compared a truck engine with a tiny cam to a 4.6L car engine used in a "sports" car. point is they are both similar in power. the really interesting thing is to see what the 4.8L engine would do with the 4.6L dohc's compression and a camshaft designed for a car rather than a 4500+ lb truck. we can speculate all we want, but I don't think its gonna happen so I'll stop there.

I'll make it simple for you. show me at least one occassion where hp/L has been decisive in deciding which car was faster. we've already seen a 115bhp/L car fall to a 72hp/L car. you're just proving that hp/L is ricer math and holds no water in an argument.

I don't need schooling on how an engine works. what do you think causes detonation? could it be... too much cylinder pressure? so one could say that a smaller engine with the same amount of hp as a larger engine has more cylinder pressure? hmm, is your peanut starting to turn now?

the blower decides how much hp you can run. what part of that don't you get? the same blower on an LS1 and 4.6L the LS1 will require less boost to make the same power as the 4.6L. once you get to a certain hp the 4.6L is going to require a higher octane race fuel and the LS1 will still be on pump gas. how is that so hard to grasp?

tiago made almost 1000 rwhp with a twin turbo 346. pump gas too. the one nitro-something dude with a twin turbo 346 chevelle is making 800 rwhp on pump gas. those are both just off the top of my head. if you think an LS1 is limited to 700 rwhp on pump gas you seriously need to research more.

an F1 engine makes less hp than a nascar engine. you can have the extra 10,000 rpm. I'll take the nascar V8. horsepower is an equation of torque. torque is created by displacement. that is a critical factor.

assuming a bone stock LT1 and a bone stock LS1, the LS1 will produce more power. it probably has something to do with heads that flow much better as well as a better flowing intake. I could be wrong though. Oh wait, no Im not.

hey! something we agree on!

think about that for a second. you're trying to jam 1000 hp through a 4.6L and a 5.7L. 1000 horsepower at 12:1 air fuel ratio and .6 brake specific fuel consumption requires 120 lb/min of airflow. this is fixed for all engines producing 1000 horsepower at 12:1 afr and .6 BSFC. lets throw some figures and equations in. a 5.7L engine with 120 lb/min of airflow, 100*F intake temperatures, an estimated 95% volumetric efficiency, and a 6500 rpm hp peak will require approximately 25.5 lbs of boost. simply changing displacement to 281 cubes increases the required boost to almost 35 lbs. now this is a rough calculation but the percentage difference is pretty accurate. do you understand now?

800 rwhp will be more reliable through a 5.7L engine than a 4.6L engine. if you can't grasp that you're retarded.


don't bother typing up a reply unless its to admit you're wrong.

Kiwibird

The K24 is part of Hondas new K series of engines.

The name breakdown is simple to read, B16= B series engine, 1.6 liter displacement, so K24= K series engine, 2.4 liter displacement.

The new K series are quite a bit more advanced then the B series, try to think of a B16-B18 engines as an LT1, and the K series, K20-K24 as LS1.

The K24 is a pretty kller engine, especially from a honda owners perspective, the extra displacment of 2.4 compared to the average 1.6 gives huge tourqe gains, making for a much more enjoyable ride, along with the extra tourqe you gain i-VTEC and dual stage intakes that honda are fond of these days.

K24's are commonly built as hybrids or "Frankensteins" as honda owners call them, this means that you take a K24 block, and put a K20 head on it. This is done becuase the K24 blocks come out of the likes of CR-V's and elements, tourqy 4 Bangers built for light SUV's. Since these arent performance vehicles the heads on the car *the most important aspect of any DOHC engine* arent built for performance, they are built for fuel economy and emmisions. These heads dont have true VTEC and arent ported to handle high RPM flow.

So, people will take the K20 heads, which come off RSX Type-S and Civic Si, or for a major bang for your buck, JDM Type-R integras with K20. The combo is easily accomplished since honda allows for engine in a series to easily swap parts, any heads can be swapped on a K series engine to any other K, same with H series, and B series.

With these new heads on the car, it now breaths very well, and has the displacement to give much more tourqe than any other honda engine, and remember, HP= torque * RPM / 5252, so more tourqe with the bigger engine, times the much higher RPM range given to you by the new head= amazing HP.

its common for people to buy a CRV/element engine block *TONS of these in junkyards from accidents* for very cheap *$500-$1000 *, go buy a Type-S/SI/R head, anywhere from 1k-3k depending on where and which, and with the engine dissasembled will add higher compression forged pistons and rods *roughly 1K for a set from eagle for K24* "Stock K24 blocks on average have 9.6:1 compresion, so pistons raise it to anywhere to 10:1 to 11.6:1"

Once the engine is built its usually thrown into an older model honda *CRX, Civic of the mid 90's, 1996 hatchback is the most sought after since it is the lightest, CRX are 2nd best choice due to its amazing chassis and lightweight design*. The engine can be installed by oneself for $250 of wiring, or can pay a shop anywhere between 1-2k to do it for you.

All in all, this leads to a very easy low 12's on street tires with JUST higher compression pistons, no head work, no cams, no gearing etc. just block, Type-S head and pistons for an average of 8k or less if you pay someone to do the work for you. high compression K24's tend to put out 300HP and well into 220 Ft.lbs of tourqe, amazing for an engine so small and in a car that weighs 2200 lbs.

I've been running into a few lately, B series junkers are still the norm, since they are so cheap still, but honda hasnt built a B series for years, and parts are starting to become more and more expensive, while K series engines are coming en mass in nearly all honda vehichles and finding themselves cheaper and cheaper every year, so K series will be commonplace in the next 3-5 years, making for some scary fast hondas everywhere in no time. So keep an eye out for them, becuase they arent cars to be taken lightly.

Asmodeus

In the world of hp/liter, a good old Wenkel Rotary is going to win every time.

Besides, a 2 liter isn't an engine size, it's a coke bottle.

300bhp/ton

No.

The thing is called curtain area.

The higher the rpms the bigger the valves need to be, this means they are heavier so heavier springs are required which means less control, more stress and wear. Multivalve solves this because 4 smaller valves can have a larger curtain area than 2 large valves, plus with added control, lighter springs and less wear.

Push rod engines can be multivalve, but’s not easy, hence DOHC is the answer. There are plenty of great OHC setups out there, just very few large displacement ones.

AAAAARRRRRRGGGGG!!!!!!!!
Look ******** the world does not start in LA and end in NY it’s a far bigger place. Don’t be so narrow minded and take a look at the big picture.

Yes you got one bit right, stupidity. But sadly it’s aimed at aging prehistoric idiots like yourself who have no concept of engineering or the fact that the world is round and contains hundreds of countries.

Well yes and no. Power to weight is usually the deciding factor.

I mean does a 1000cc motorcycle have MASSIVE HP? No, but what it does have is fantastic specific output and power to weight, hence even 600hp cars will struggle to play ball with one.

Well cost is a difficult thing to pin point. The Ferrari engine in reality won’t cost anymore to build in terms of materials. However labour and manufacturing process may add more. And as the engine is intended to be fitted to a car costing over double the amount it’s a lot easier for Ferrari to add a higher markup making it look like it cost more.

Fuel consumption is something you can not compare, the vehicles fitted with the engine will have a bigger bearing on mpg than allows for comparison. The Vette has things like really tall gearing and CAGS which all add a discrepancy to the figures.

300bhp/ton

You evidently didn’t READ my post. I couldn’t care less which has the most HP. All I’m trying to state is as a rule DOHC engines can produce a greater specific output and remain production legal and streetable.

So therefore two engines of the same displacement the DOHC will have greater HP potential.

This isn’t a difficult concept, and damn it’s not frigging rocket science is it!

Equal basis being same displacement and fuel, emissions and legal requirements. Al lthe things that are consider by car makers when designing a engine.

No not at all and this is where you naivety really shows. An efficient combustion engine is so much more the the burn cycle the head design the port design how the gas is extracted.

You are simplifying it far too much to the point where its pointless.

Yes it does. On a 2v per cyclinder setup the cylinder has no knowledge of whether it is OHC or OHV, or if you really want to be fancy over head intake and side exhaust.

To make more power you need to increase the breathing, larger valves are required. But larger valves mean heavier springs. Now a OHV has more valve train shunt and resistance than most OHC’s. At low rpm’s this doesn’t matter but as rpms increase so do the forces involved. An OHC will run at higher rpms with more stability and reliability than OHV. And going back to the equation for HP means more HP can be achieved.

The thing to do here is not confuse the stroke of the engine with the valve train. OHV offer no increase in low end grunt over OHC technology. It’s just most OHV’s are long stroke motors which favour lower rpms and make more low end grunt. Because OHC can handle higher rpms most of the OHC’s are shorter stroke motors which means better for high rpms and will tend to make less low end grunt.

BUT the limitation of 2v per cylinder is the same for both OHV and OHC.

EXAMPLE:

Operational range of an engine (LS1) is say 1500-5500rpm. By adding a wilder cam and allowing it to breath better (heads/valves) you will generally not increase this operational range but simply move it up the rpm range. Thus going back to the HP equation allowing more HP.

A TREX cam will favour 3500-7000rpm. So we have been able to extend the upper rpm range but at the degregation to lower rpms performance.

A 2v OHC will be affected in the same way.

What multivalve does ([b]REMEMBER a multivalve engine can be a push rod engine, there is a company that makes 4v per cylinder heads for the LT1). Is allow greater curtain area. This means more control at the lower rpms but better breather in the high rpms even when using a milder cam.

Example of a multivlave engine operation range (in this case DOHC):

1500-7000rpm. See it matches the 2v engine with the stock cam in the low rpms, but it has the ability to match it in the high rpms when compared to the aftermarket cam.

This extra control and breathing ability means a multivalve engine can achieve higher specific outputs, or bhp/litre with out facing the same issues as a 2v motor, be it OHC or OHV.
Now, multivalve OHV engines are very very rare, this is because you only have one cam to drive 32 valvles . And the added stress on the push rods is immense. This ultimately reduces durability and limits how high in the rpms it can be safely used. Thus limiting it’s potential.

Other solutions include 32 valve SOHC setups, you have one cam per bank. This is a complex setup but possible. The current mustang engine is a SOHC unit, but has 3 valves per cylinder.

As a rule the most obvious answer is a DOHC setup, which is why outside of America this setup is the main stay of nearly EVERY Vee engine in production, be it V6, V8, V10 or V12. Most 4 cylinder engines also use this technology and it has now even crept into the diesel arena because of it’s superior ability.

The valves train does not have to be over complex. And also a valve train consists of more than just a chain.

An OHV requires a chain plus 16 push rod which then act rockers. In each instance where two components touch there is slack and unwanted friction, plus the mass of moving compents is high. Hence OHV’s generally do not rev as high.

A OHC can have the cam acting directly on the valves. So it is much more direct. Plus modern belt design means a single belt can be used to power all four cams.

Both setups are complex, but for different reasons. If DOHC is so difficult why are the majority of the worlds engines OHC designs?

I think I just have

Very good, would you like a cookie?

Because sadly that’s the level you have dropped yourself too.


How does it get run down?

Ferrari neither needed nor wanted more than they produced. They have plenty of other options for making more power if the wish. The V12 from the Enzo is still SMALLER displacement than the LS7 but produces near 150bhp more.

They are different engines designed for different purposes.

[b]PLUS I was highlighting the ABILITY of the different technologies. But saldy this seems to have been to complex for you to grasp.

IF, IF Ferrari built a 7.0 litre engine to the same state of tune as it’s current 4.3 V8 it would produce over 800bhp STOCK!!!!!

This may be hypothetical but it doesn’t alter the physics behind it. And for real world proof that this ability exists I already sited the 7.7 litre TVR engine.


Why, they don’t need it. The F430 is a fantastic road car aimed at a totally different market to the Vette.

It’s a CAR!!!! Not a wrestling match. Nothing beats up the other.

Look you really can’t be this stupid, I mean you guys put a man on the Moon for ***** sake!!!!

It’s an example of what is possible, the fact they have NO need to produce such engines doesn’t alter it. V8’s are not popular outside of America. So why would any company waste money producing something they

a) don’t need
b) and don’t want?

As I said, show me TWO production OHV’s which can achieve better than 100bhp/litre n/a STOCK.

There are plenty of OHC engines and also plenty which produce far more HP than the LS7 does.

STUPID STUPID – there is never a sole reason. You are confusing engine stroke with how an engine makes power.

More cylinders mean you can run the same displacement with less stroke, which yes can in turn allow higher rpms and more power.

But this is a street engine, we are not talking about 19,000 rpms so it is pretty pointless to look at this limitation.

So you dispute the DOHC technology in the TVR V12. Do YOU really think had it been OHV and 2 valves per cylinder that it could produce the same HP?

The Viper engine is larger by 0.6 litres, and has 10 cylinders yet it only manages 500bhp STOCK. And even modded will still struggle to make 95-100bhp/litre for street use.

This goes EXACTLY to specific output!!!!

A Formula 1 V8 from last year was capable of making 900bhp from 3.0 litres. Would a OHV 3.0 V8 be able to produce 900bhp?

300bhp/ton

WTF??? The truck engine is not any real different to a car engine. Come on live in the real world here, it’s not like you where comparing an 18 wheeler was it?

What is the SCR for the 4.8?

I think the Mustang is ~10.1:1 SCR

Speculate about what? You provided a comparison which contradicted what you where saying?

And plus I’ve already said the Ford OHC is NOT an idea candidate as it’s not the best engine there is.

Take a TVR 4.0 Straight 6 engine, according to your wisdom less cylinders make less power. But this little DOHC engine produces 406bhp as a PRODUCTION engine. That’s more than a Ls6 or a LS2.

And yes you can mod the LSx motors, but you can also mod the TVR engine aswell. Although ultimately in this case I believe the LSx engines should be able to produce more total HP, but this is just due to massive variance in displacement.

Right first off WTF has this got to do with the ability of DOHC engines? – NOTHING!!!!!!

2nd if you want to play with fire prepare to get burnt:

Corvette LT1 OHV V8 vs Corvette LT5 DOHC V8

Which is more powerful and which is faster?

And conveniently they are the same displacement in the same car and the same configuration.

And yes I know the Ls1 is more powerful than a Lt1, but surprise surprise the LS1 didn’t exist in the LT5’s day. If there was a modern Lt5 in production NOW it would produce substantially more HP.

If you want more READ my previous sodding post you moron!!!

-Ford Cammer 427
-Rover V8 OHC converted by Cooper

The rest of your posts says you do!



You have no idea do you!

Take an engine, add fuel mess about with the tuning and timeing. Tada!!!!!! Detonation. Restore the setting no detonation but the cylinder pressure will have remained constant.

Detonation, aka knock or pre ignition is where the fuel prematurely ignites before the piston reaches TDC. Heat and fueling are usually the prime factors and as FI engines use compression on the intake charge it produces heat and as a result of the greater density of oxygen more fuel is required thus resulting in more likelihood of detonation.



Again you seem to be totally not understangin what pressure and volume are.

Think of it this way take a bicycle tyre and inflate it to 30psi (pounds per square inch). Then take a 35” off road tyre off a Jeep and inflate it also too 30psi.

Now each tyre has the same pressure pushing on the inside of the tyre. BUT the Jeep type has a far greater volume, maybe 20 times more.

Now inflate the bicycle tyre to 40psi. It now has far greater pressure in side the tyre, but it still has far less volume. The Jeep tyre still contains more air.

Engines are no different.

A 4.6 making 14psi of boost has the exact same pressure as a 5.7 with 14psi of boost. But the volume of air will be different.

This is just in it’s simplest form as things like SCR will have an affect on how much boost can be run. A lower SCR means cylinder pressure will be less even when running the same boost.

But the HP generated still goes back the specific output of the engine.

An extreme 2.0 DOHC turbo setup can make 800bhp, that’s 400bhp/litre. So would a 5.7 litre Ls1 be able to produce 400bhp/litre (2280bhp)? I’ve never heard of one in a street car, have you?

But it doesn’t, you are confusing the issue here.

Take GMR Speed’s single turbo kit for the LS1 Fbody, the turbo is capable of handling 900bhp. But you’ll never see that power from it, because of other limitations.

Again I think you are confusing the point.

First off we are back to the psi and volume thing.

In theory if you have 14.7psi of boost (or 1 bar which is equal to 1 atmosphere) you will have effectively double the effective engine displacement.

However, boost at the turbo is different to boost once it’s reached the cylinder. Plus things like heat and HP taken to drive the turbo/blower all means you’ll get less HP in return than you may have initially expected.

So the volume of air will vary. Or if you want the same amount of volume the larger engine will require less boost.

Specific output will then determine how much HP is produced. This again goes back to curtain area and the advantages of multivalve engines.

PLEASE PLEASE, if you are unsure about what curtain area is and how it’s achieved go and research it, this is what I did. Else it is a completely wasted argument.

Also don’t forget Compression Ratio. Remember adding boost will effectively increase the CR. This means more risk of detonation.

The Terminator has a SCR of 8.5:1 where as the Ls1 is 10.1:1 this means in n/a form the higher CR produces better specific output. But will enable less boost. The lower CR means more boost and overall more gain.

Most serious FI guys will drop their SCR down to 8.5:1 for turbo’s and 9.1:1 for superchargers. This allows more safety and more Hp potential.

BUT:

Take a stock LS1 add 9psi of boost. And take a LS1 with 9.1:1 CR and also add 9psi of boost. The stock motor will produce the higher HP.

However, the 9.1:1 CR block will be able to handle 14psi on pump where as the stock motor probably can’t without detonation. So ultimately the lower CR has more HP potential.



It’s not that simple. My claim is just how close a 4.6 DOHC can get to a 5.7 OHV on pump fuel. And the answer is pretty darn close.

Now go on, go find a LS1 346ci built running FI (TT’s) and find out what is the maximum attainable on the STREET not dyno running 93 octane.

Can you provide any proof?

AAAARRRRRGGG!!!!!!!!

One again you can not be this STUPID!!!!!!

It’s a proof of concept I’m trying to convey.

If the NASCAR engine was limited to 3.0 litres would it still produce more HP?

Or if the Formula 1 engine was allowed the same displacement as the NASCAR engine, which would have the most power?


But what has this got to do with OHV compared to OHC????


NOTHING!!!!!!!!!!!!

You can have small displacement OHV’s and large displacement OHC’s. no really


YEAH and that’s SPECIFIC OUTPUT!!!!!!

LT1 275bhp = (275 / 5.7) 48bhp/litre

LS1 345bpb = (345 / 5.7) 61bhp/litre

IT’S PRETTY SIMPLE REALLY!!!!


Again boost is a measure of RESTRICTION.

Again no account of SCR!!!



Really?

I admit I’m wrong if the laws of physics no longer apply.

Since they do it’s pretty difficult.

If you don’t want to take my word, go RESEARCH it and come back with some proof and evidence.

ss1129

iTrader: (16)

So a cam with more duration and lift does nothing? Last time I checked even when adding big heavy springs and huge valves on average.....I may be going out on a limb here, but I thought you would actually gain hp. I guess everyone who has done a cam swap is stupid for thinking they would get more power. Damn lying dynos.



Um....my world does. I could really give two ***** what europe thinks about hp per liter....but I cant really remember the last time Car and Driver or Motortrend actually mentioned this hp per liter thing, but Im pretty sure its in mentioned in Honda Tuner and almost any other sport compact magazine.



Well yes and no. Power to weight is usually the deciding factor.

No ****....you mean a 200 hp bike that weighs 300lbs can keep up with a 600 hp car that weighs 3400 lbs? Get the **** outta here!!


So a 2.4L with a turbo doesnt use as much gas as a 346 n/a motor? You are ******* retarded talking about CAGS. Gearing is an issue, but again its up to the manufacturer on that. When the consumer changes those out its on themselves on how much mpg they get.

Anyways, if you have a 2.4 dohc motor sucking in the same amount of air as a 5.7 because of its nifty design, wouldnt it be sucking just as much fuel to prevent detonation unless it was running at a lower compression ratio?

uno

You quoted me in there somewhere. And i agree, it's all about power:weight , a useable powerband, traction and gearing.