What makes an engine able to make more power on pump gas?
08-30-2010, 10:41 AM
#41
http://mercuryracing.com/1350/specs/
552 cid, quad cam, 4v, and twin turbo's. 1350 hp, 91 octane, and a warranty.
08-30-2010, 02:33 PM
#43
Yes. Better chamber shapes, intercooling, and lowering compression are all effective methods of suppressing detonation.
08-30-2010, 03:42 PM
#44
TECH Fanatic
Thread Starter
iTrader: (5)
Join Date: Apr 2005
Location: Phoenix AZ
Posts: 1,005
Likes: 0
Received 0 Likes
on
0 Posts
Here is a problem. http://www.youtube.com/watch?v=vPeSM5MZFho
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
08-30-2010, 05:36 PM
#45
Here is a problem. http://www.youtube.com/watch?v=vPeSM5MZFho
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
08-30-2010, 05:45 PM
#46
TECH Fanatic
Thread Starter
iTrader: (5)
Join Date: Apr 2005
Location: Phoenix AZ
Posts: 1,005
Likes: 0
Received 0 Likes
on
0 Posts
From what i remember ove my years is that inline engines are best for tq and flat are good for hp. But that might just be an old wives tale. Im sure someone will sort it out.
08-30-2010, 08:40 PM
#47
If you guys ever get a chance, pick up a bare 2JZ block. Do some military presses and curls with one. LOL. A 2JZ long block weighs about 450 lbs. That's more than a wet LSX complete motor. So if you are wondering what keeps it together, the answer is IRON.
08-31-2010, 10:40 AM
#49
TECH Fanatic
Thread Starter
iTrader: (5)
Join Date: Apr 2005
Location: Phoenix AZ
Posts: 1,005
Likes: 0
Received 0 Likes
on
0 Posts
Would the weight or strength of the block make a big difference? I havent heard of people breaking the block. Or is distortion the issue? Havent heard of people saying that the block has even been the issue. Especially if ya use an aftermarket iron block.
08-31-2010, 12:19 PM
#50
On The Tree
Join Date: Mar 2006
Posts: 150
Likes: 0
Received 0 Likes
on
0 Posts
Yes it dose make a difference.
Just because you don’t break the block doesn’t mean anything.
The block will flex and pinch the pistons and rob you of power
break rods and all kind of stuff that get blamed on other things.
Just because you don’t break the block doesn’t mean anything.
The block will flex and pinch the pistons and rob you of power
break rods and all kind of stuff that get blamed on other things.
08-31-2010, 11:34 PM
#51
If a block is going to come apart due to too much HP it usually splits right up the middle, between the two banks of cylinders. If you have an inline 4,6,8 anything there is only one bank. That's why they can take the punishment, you don't have two opposing cylinder banks trying to split the block.
As far as flex is concerned there is flex in an iron block, but not near as much as an aluminum block. Think of cast iron as glass and aluminum as plastic. Iron block can take more stress and stay stable right up to the breaking point. Where as aluminum will start to distort earlier and cause other issues with the rotating assembly before it finally quits.
As for the 2jz making big numbers, look at where its making that power at, around 8000rpm. A 6.0 (with comparable chambers) can make that number at considerably less rpm. Less rpm usually means better gas mileage and less punishment, and that means cheaper parts.
A good case in point is to compare the engines of a Lambo Gallardo and a Z06. The Lambo (5.0) makes a little more horse power but spins much higher rpm then an LS7 (7.0), has more compression, and uses more fuel (20 hwy compared to Z06's 28 or better). And the performance between the two usually has the Z06 ahead. Now, turbo these cars, and at (just examples here) 20lbs the Lambo makes 1000hp and runs on 93octane, but the vette can only handle 15lbs on 93octane (due to the chamber design). And makes 100 less HP.
Now, cubic inches comes into play. Though the corvette is low on HP, it has an abundance of torque. And at the drag strip the two race, and the vette is all traction (not likely) and dispatches the gallardo to "also ran" status.
As far as flex is concerned there is flex in an iron block, but not near as much as an aluminum block. Think of cast iron as glass and aluminum as plastic. Iron block can take more stress and stay stable right up to the breaking point. Where as aluminum will start to distort earlier and cause other issues with the rotating assembly before it finally quits.
As for the 2jz making big numbers, look at where its making that power at, around 8000rpm. A 6.0 (with comparable chambers) can make that number at considerably less rpm. Less rpm usually means better gas mileage and less punishment, and that means cheaper parts.
A good case in point is to compare the engines of a Lambo Gallardo and a Z06. The Lambo (5.0) makes a little more horse power but spins much higher rpm then an LS7 (7.0), has more compression, and uses more fuel (20 hwy compared to Z06's 28 or better). And the performance between the two usually has the Z06 ahead. Now, turbo these cars, and at (just examples here) 20lbs the Lambo makes 1000hp and runs on 93octane, but the vette can only handle 15lbs on 93octane (due to the chamber design). And makes 100 less HP.
Now, cubic inches comes into play. Though the corvette is low on HP, it has an abundance of torque. And at the drag strip the two race, and the vette is all traction (not likely) and dispatches the gallardo to "also ran" status.
09-01-2010, 06:31 AM
#52
The foxbody block splits in the middle, but thats not the rule for iron blocks.
I agree with TT350. If the block isn't strong enough, something else usually gets taken out before the block splits - iron or aluminum.
...and the vette is not limited to 15 psi because of chamber design - this is rubbish. Most LSx budget builds will start to push water in the 18-22 psi range. The LSx wasn't designed with high charge pressures in mind, so the stock head bolting doesn't accomodate it.
I agree with TT350. If the block isn't strong enough, something else usually gets taken out before the block splits - iron or aluminum.
...and the vette is not limited to 15 psi because of chamber design - this is rubbish. Most LSx budget builds will start to push water in the 18-22 psi range. The LSx wasn't designed with high charge pressures in mind, so the stock head bolting doesn't accomodate it.
09-01-2010, 06:54 AM
#53
guys, if you really want to see the ultimate piston engines you really need to look at the WW2 engines that whwere kicking about back in the 1940s! people where REALLY pushing the limits of engine and design to the limits and often well beyoned.
engiens worth looking at: RR Merlin and Griffon (note the extra 30% CC of the Griffon dose not net the engine and extra 30% increase in power!), the Napier Sabre, some of the german hyper engines (there was a 24 cylinder water cooled radial that used 6 x 4 cylinder inline blocks around a common crank) and obviously the radial engines.
To sum up though, Napier found that they would build a 5500bhp engine from something like 36ltr where as the most people could get out the same sized RR Griffon V12 was 3500bhp. Also to meet the Sabres power you needed a much larger engine (Major Wasp) and then you lost out on weight and fuel consumption.
really intresting stuff.
Chris.
engiens worth looking at: RR Merlin and Griffon (note the extra 30% CC of the Griffon dose not net the engine and extra 30% increase in power!), the Napier Sabre, some of the german hyper engines (there was a 24 cylinder water cooled radial that used 6 x 4 cylinder inline blocks around a common crank) and obviously the radial engines.
To sum up though, Napier found that they would build a 5500bhp engine from something like 36ltr where as the most people could get out the same sized RR Griffon V12 was 3500bhp. Also to meet the Sabres power you needed a much larger engine (Major Wasp) and then you lost out on weight and fuel consumption.
really intresting stuff.
Chris.
09-01-2010, 08:03 AM
#54
i understand all the flex problems. but there is so much out there to help it
09-01-2010, 08:25 AM
#56
I also don't believe that the lambo motor will make more power on pump gas as a rule. Specially when talking 5.0 vs 7.0. I'll take the cubes any day. The biggest advantage of the 4v/cyl design is the head flow at significantly lower lift with smaller (lighter) valves. This makes valve control easier at higher rpm.
As for the WW2 stuff, they were hosing those things down with meth/water to keep them from detonating.
Enter E85 and the penta chamber can SUCK IT!
09-01-2010, 04:50 PM
#57
Correct. It's not about boost. It's about cylinder pressure. You can run 8:1, 20 psi, 8* of timing.
I also don't believe that the lambo motor will make more power on pump gas as a rule. Specially when talking 5.0 vs 7.0. I'll take the cubes any day. The biggest advantage of the 4v/cyl design is the head flow at significantly lower lift with smaller (lighter) valves. This makes valve control easier at higher rpm.
I also don't believe that the lambo motor will make more power on pump gas as a rule. Specially when talking 5.0 vs 7.0. I'll take the cubes any day. The biggest advantage of the 4v/cyl design is the head flow at significantly lower lift with smaller (lighter) valves. This makes valve control easier at higher rpm.
My point is however, the Lambo will never make as much torque down low. Why? lack of cubic inches. And as beautifull as 1000hp sounds at 8000rpm, I would rather have 1000lb/ft at 4000rpm.
What I am saying is that yes, the four valve head design IS the best design to stave off detonation. These little inlines and exotics with these heads can make some big numbers on pump gas. They can take more boost on pump gas then our GM's because of this. They can rev higher because of the light valves and lack of pushrods. But these little engines need these heads to make up for a lack of cubic inches.
But they can never make up for the torque. And thats what I love about American cars. Torque is what wins races and what spins those tires. And the best way to get that torque is with a bigger engine. End of story.
The OP asked why these exotics can get the PSI and power that they do on pump gas, I feel the common denominator is the head design. yes timing, cooling, compression all play a part but when you factor all that out (because you can adjust all that on any engine) the head design is what is left. But so many people concentrate on HP.
HP comes from torque. You decide how much torque you want, and where you want it in the rev range and the horsepower will take care of itself.
If I had my choice I would take cubic inches over 4 valves heads anyday. But man o'man if i could have both...
09-01-2010, 07:03 PM
#59
Here is a problem. ...
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
This is what i mean. I am gathering from this thread that there is certainly difference that make the 2jz run so well but it seems odd that there is a engine that can make this much power on pump. I understand that i cant take the "well its 3.0 liters and im 6.0 so i should be capable of making 2x as much. But it seems that there is something that Im missing in this equation. Maybe its just a matter of money in the right spots. Maybe the supra guys can compete in the big races so they pick small specific vistories and go ***** out. Just boggels the mind.
Then it hit me. . . E85. Technically, it's pump gas, but has the detonation resistance of some race fuels. I've heard of 30+ psi on this "pump gas", and I'd be willing to be that's what they were running.