This can be seen as a bit off topic. So I'll just link to some math I've already done. 15% drivetrain loss: 500 X 15% - 40hp rotational energy loss in the tranny if it were frictionless. Do you know how MUCH heat energy equals the additional 35whp loss? You really should measure the heat difference in the transmission from say 200whp to 500whp, then tell everyone how much horsepower was actually lost to heat.

Just have to add . . .

KE of rotation = 1/2Iω^2

KE of rotation = 1/2(τ/α)ω^2

I (moment of inertia) is a constant for each mass or colection of different masses because I = mr^2. m is mass and r is radius. Also, I = τ/α. As α (angular acceleration) goes up so does the τ (net external torque) to keep I constant. KE stays the same. So apparently it does take the same amount of energy to freewheel a drivetrain to 7500rpms no matter what horsepower you're engine has.

Heat was generated by friction which is exactly my point

It is off topic but yeah it's not actually a percentage.. but a logarithm... The faster something tries to move or accelerate through a substance (oil, gears, bearings, rotational mass), the more friction and counteracting force (resistance) is created, although the resistance increase gets smaller. The faster something goes, the more resistance it encounters... there is not a set value of resistance from a transmission

here's a quick example of a logarithm from wikipedia

This could easily be a graph of how the change in output (friction, etc) increases rapidly at first, and changes to a slower increase as the input (horsepower, speed, etc) increases.

It is easiest to think of driveline loss like wind resistance... the amount of resistance (work loss) increases (disproportionately) with the increase in speed... otherwise it would only take about 10hp to increase your top speed by 10mph... not true

It does take about 238HP at the crank for the average AWD car to show 200AWHP
and about 400HP for the same car to generate 345AWHP
These are just numbers I'm making up from what I learned in past experience, but you get the picture...

It's been a while but I've read dyno sheets that were proving the driveline loss.. they had an engine dynometer as well as a chassis


but this still doesn't answer my question... How many miles do these 500+hp composite-gasketed engines have on them without leaking?

Well, since it takes no more KE to spin the mass no matter the HP of the engine; and the drive train loss at 200whp is 38hp and at 400whp, its 55hp; then there's 17hp loss difference because of friction. Therefore, since 1hp=746watts, there is 12,682 watts of heat energy in the transmission? At only 400whp??? Can we say welding bearings, and gears too soft to accelerate the car without shearing the teeth. I'm very confused.

Jeez, I can't help myself and correct me if anything I'm saying is wrong here, but here's how I understand the concept of kinetic friction. . .

Since the gear cogs slide on each other to spin, they experience standard kenetic friction with a lower coefficient of friction than metal-on-metal because of the gear oil. The definition of kinetic energy loss due to friction is 'coefficent of resistance times the sum of the normal forces times distance'. Since:

1) kinetic energy = 1/2 X Force X Distance,
2) and distance is constant in the rubbing of the gear cogs on the gearset,
3) and the increase in horsepower is directly proportional to the normal forces applied on the gear cogs since number one is true

Then, the increase in horsepower is directly proportional to the kinetic energy loss due to friction. There is a linear relationship. Oil viscosity decreases as the directly proportional amount of heat increases, this is where the coefficient of friction starts to increase slightly. Therefore there is actually a gradual increase in frictional loss due to the frictional coefficient changing as the oil viscosity goes down. Now one oil does better than another. But nearly all proper/good tranny oils function rather well (no change in viscosity and consequently the coefficient of friction) at 400-500whp levels. This loss in viscosity is more of a sudde change. So the directly proportional relationship of the increase in friction to the increase in horsepower is fairly constant up to the point that the oil breaks down. And the kinetic energy lost is VERY small since it equals sum of the small distance the gear cogs rub each times the force applied divided by 2.

Therefore, there's just not much energy lost in friction. The heat is not there to suppliment the supposed loss. If it were, it would melt things. Nor does the calculation of the theoretical kinetic energy loss due to friction lead to a large number that would equal the difference supposed by a 15% drivetrain loss at 400whp.



I know of 2 guys with 500whp setups that hold the stock head gasket (6-bolt blocks with the wider ARPs) for years. I'm pretty sure if you search around you'll find a few mentioning their setup capable of doing it. I've had mine daily driven holding and running 47 lb/min peak with my 60-1. And I blew the turbo at 52 lb/min (agp rs60t) , but the composite headgasket was not pushing coolant. Now, their setups nor mine demonstrated even minor detonation. This is what kills the composite gasket at this level. Not the normal pressures of 500whp. This is the good and bad thing about the MLS gaskets. They deal with the detonation spikes and let all that pressure and heat finish off at the piston top. If you have forged pistons, you have a setup that is very durable, can run through a string of knock at 500whp and take it like a stock setup can handle it at 200whp. But at 500whp you start to melt/pit/crack the stock pistons very easily, if the pressure and heat don't leave the chamber via a headgasket blowout.

Based off the title along.

What Timing belt would people suggest?
Not really high boost but 400hp numbers..

OEM?
Gates?
Kevlar?
HKS?

dsm-onster said:

Well, since it takes no more KE to spin the mass no matter the HP of the engine; and the drive train loss at 200whp is 38hp and at 400whp, its 55hp; then there's 17hp loss difference because of friction. Therefore, since 1hp=746watts, there is 12,682 watts of heat energy in the transmission? At only 400whp??? Can we say welding bearings, and gears too soft to accelerate the car without shearing the teeth. I'm very confused.

Jeez, I can't help myself and correct me if anything I'm saying is wrong here, but here's how I understand the concept of kinetic friction. . .

Since the gear cogs slide on each other to spin, they experience standard kenetic friction with a lower coefficient of friction than metal-on-metal because of the gear oil. The definition of kinetic energy loss due to friction is 'coefficent of resistance times the sum of the normal forces times distance'. Since:

1) kinetic energy = 1/2 X Force X Distance,
2) and distance is constant in the rubbing of the gear cogs on the gearset,
3) and the increase in horsepower is directly proportional to the normal forces applied on the gear cogs since number one is true

Then, the increase in horsepower is directly proportional to the kinetic energy loss due to friction. There is a linear relationship. Oil viscosity decreases as the directly proportional amount of heat increases, this is where the coefficient of friction starts to increase slightly. Therefore there is actually a gradual increase in frictional loss due to the frictional coefficient changing as the oil viscosity goes down. Now one oil does better than another. But nearly all proper/good tranny oils function rather well (no change in viscosity and consequently the coefficient of friction) at 400-500whp levels. This loss in viscosity is more of a sudde change. So the directly proportional relationship of the increase in friction to the increase in horsepower is fairly constant up to the point that the oil breaks down. And the kinetic energy lost is VERY small since it equals sum of the small distance the gear cogs rub each times the force applied divided by 2.

Therefore, there's just not much energy lost in friction. The heat is not there to suppliment the supposed loss. If it were, it would melt things. Nor does the calculation of the theoretical kinetic energy loss due to friction lead to a large number that would equal the difference supposed by a 15% drivetrain loss at 400whp.

Click to expand...

Don't be confused.. Kinetic Energy = (Mass * Speed^2)*1/2
What does 12,000W translate into Temperature? not as much as you make it sound... but the tempurature would still be enough to weld everything up if there weren't any oil or heat dissipation... Have you ever seen or heard of a tranny that ran dry? The moving parts weld together

but the friction/heat created is dissipated long before it can melt anything... the cooling effect of the oil and engine and the rest of the driveline: the heat finds its way into the air...

Nowhere did I say that all of the energy is lost through friction, and thank you for pointing out that a lot of it (most of it) is lost as kinetic energy...

I feel you're taking this too far demonstrating your knowledge of physics.. I'm impressed and you make me realize how rusty I am with formulas... but my whole point was that SAE corrected horsepower is figured out through a logarithm.

Do you believe that a 500hp setup loses an equal amount of HP through the driveline to a 200hp setup? The answer is no because FORCE is increased... Btw you also have to factor in the coefficient of friction of the gears, oil, bearings and tires... all of these energy losses increase as the force is increased... (F/N = μk)... μk being the coefficient of kinetic friction. The coefficient of friction is there and you know it. I'd also like to mention that eventually, all the kinetic energy in the driveline turned into intertia, that didn't make it to the dynometer, is absorbed by the brakes or something else (once again turned into heat)...

dsm-onster said:

I know of 2 guys with 500whp setups that hold the stock head gasket (6-bolt blocks with the wider ARPs) for years. I'm pretty sure if you search around you'll find a few mentioning their setup capable of doing it. I've had mine daily driven holding and running 47 lb/min peak with my 60-1. And I blew the turbo at 52 lb/min (agp rs60t) , but the composite headgasket was not pushing coolant. Now, their setups nor mine demonstrated even minor detonation. This is what kills the composite gasket at this level. Not the normal pressures of 500whp. This is the good and bad thing about the MLS gaskets. They deal with the detonation spikes and let all that pressure and heat finish off at the piston top. If you have forged pistons, you have a setup that is very durable, can run through a string of knock at 500whp and take it like a stock setup can handle it at 200whp. But at 500whp you start to melt/pit/crack the stock pistons very easily, if the pressure and heat don't leave the chamber via a headgasket blowout.

Click to expand...

Now this is the kind of information where I really learn something... thank you I've been trying to find out this kind of information for a while now... you're the first person to actually give some explicit input

that makes sense... I never really thought of it this way, and it makes me realize my new setup is prepared to handle high-HP knock... Your input has actually made me feel confident in my choice of components

xxShaneOmac said:

Based off the title along.

What Timing belt would people suggest?
Not really high boost but 400hp numbers..

OEM?
Gates?
Kevlar?
HKS?

Click to expand...

taken from a website:

"Gates Racing Timing Belts Features :

Gates Racing Builds the belts for Power Enterprises in their Gates Unitta Plant in Japan. Power Enterprises sells timing belts to Performance Distributors Greddy , Toda And HKS.So if there is Any questions about the quality of this Timing Belt , These are the Same quality as Most Performance Timing Belts brands that you can find ."

Click to expand...

Only the Gates/power enterprises are made with blue rubber, although it's the same rubber as the HKS/ Greddy

if you want something extremely high quality, there it is... and for 1/4 the price of the HKS
eBay Motors: 93-96 MITSUBISHI MIRAGE GATES BLUE RACING TIMING BELT (item 360076968807 end time Aug-12-08 10:10:05 PDT)

Very valid points. Please trust that I don't think it's possible to give my point of view of a physical occurance without giving the reason why. Even scientific laws are opinion in a sense. Because there may be more to it than what seems. I just was giving the reason why I believed something based on the information I knew. Thank you for responding!

I'm glad you feel more confident about your setup. Your setup looks very thought out. You're block is ready for a bigger turbo for the street and you can be confident that you can deal with a bad string of knock without [too] much worry.

FWIW: I have run a stock composit head gasket and a over the counter $30 fel-pro composite HG at over 650awhp a few times. They will hold, the gasket is not the problem. None of them have lasted forever for me but at these power levels nothing does. I am always pulling the head off for some reason. I cant even get 3000 miles on some oil, .
Like Hal said. the studs make a big difference.
I run the ARP L19's. SS O-rings in the head.
ARP has made L19's for a long time but not for 4G63's
I think some people used to drill and tap the block to use V8 ARP L19 studs.
A company called A1 Technologies made them of H11 tool steel (I think the same stuff as L19's) and Magnus Motorsports sells them. Then at some point someone had the ARP's ordered through ARP's custom department for DSM's.
Either is pretty much the good stuff. The ARP L19's come with standard nuts and washers as the problem area is in the stud. I think the A1's come with the upgraded nuts but I am not sure.
These studs can be reused over and over aain and you really should not reuse standard ARP's much. That also offsets the cost.

After all that said and I am switching the HG... The new setup will be decked head, Fel Pro MLS and L19's.
Both ways should be pretty much bullet proof.

Freerevving said:

Only the Gates/power enterprises are made with blue rubber, although it's the same rubber as the HKS/ Greddy

if you want something extremely high quality, there it is... and for 1/4 the price of the HKS
eBay Motors: 93-96 MITSUBISHI MIRAGE GATES BLUE RACING TIMING BELT (item 360076968807 end time Aug-12-08 10:10:05 PDT)

Click to expand...

^^^^That is a holy **** cheap price on ebay. I wonder about authenticity
I run the Gates Premium timing belt. I love it + I sold the balence shaft belt that came with it and offset the cost even more.

Everything about the A1 studs is hardcore/badass. I run the in the RWD. The head was oringed with some huge ring, 13 thousandths protrusion IIRC. Since this head has tons of port work in it I didn't want to cut the head frivolously, so I had Edgar just cut the oring down flush. Done more as an experiment to see would happen. So far with A1s at 86 ft lbs IIRC and the Felpro MLS I've been to 40+ psi with no issues. I'll run it until I have a problem with it.

I am either at 500 awhp or real close, I have ran nothing but stock OEM composites and a fresh set of standard ARP's.

2gAWDTalon said:

^^^^That is a holy **** cheap price on ebay. I wonder about authenticity
I run the Gates Premium timing belt. I love it + I sold the balence shaft belt that came with it and offset the cost even more.

Click to expand...

yeah except that's the wrong link

eBay Motors: ECLIPSE TURBO 4G63 ENGINE GATES BLUE RACING TIMING BELT (item 260272494795 end time Aug-14-08 20:44:42 PDT)

they can be found for $90

Well I was admiring the L19's... as I like well crafted metals. But I still believe that they are for 600+hp and I don't have a good excuse to buy them
This is the first time I've heard of reg ARP's not being reusable

They are reusable, but IIRC, there is a .001" stretch limit. How many of you guys are tracking bolt stretch when you reuse them?

This a great tread. Did get off the topic, but none the less a great topic. Does anyone know if you can use felpro p/n 1153-1 with the 7 bolt 4g64 block bored .20 over? I see that stephen is using it. But, with the 4g64 block. I was under the impression, that felpro only made a headgasket for the 2.0 liter block.