What's good about the 7age?

IndiaDorifto7
Club4AG Expert
Posts: 224
Joined: Sat Feb 15, 2014 7:34 am

What's good about the 7age?

Postby IndiaDorifto7 » Mon Apr 20, 2015 3:54 pm

I'm looking at engine swaps/builds and this came up. It seems like a neat option because 7afe engines should be pretty easy to source and cheap(no one really bats an eye at a '95 corolla dx/le anyways). Why do people do this swap and what's so great about it?

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Mon Apr 20, 2015 6:13 pm

IndiaDorifto7 wrote:I'm looking at engine swaps/builds and this came up. It seems like a neat option because 7afe engines should be pretty easy to source and cheap(no one really bats an eye at a '95 corolla dx/le anyways). Why do people do this swap and what's so great about it?


More torque which is better all around.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Mon Apr 20, 2015 6:14 pm

IndiaDorifto7 wrote:I'm looking at engine swaps/builds and this came up. It seems like a neat option because 7afe engines should be pretty easy to source and cheap(no one really bats an eye at a '95 corolla dx/le anyways). Why do people do this swap and what's so great about it?

If done right (and I must stress that because so often it's not) it will gain you good power across the curve. It takes you from 1.6 liter to 1.8 liter. It's not a massive improvement but the cost to gain and as you mention the availability makes it pretty tempting.

I would say the only downside is that it limits the redline in extremely high RPM builds the stroke and it's effect on piston speed means you wouldn't want to put it in a 12k RPM screamer. It's also not real well defined on just how much the stock crank can take because not many have pushed it past it's limits.
On the other hand for an 8000 RPM or less build there really isn't any good reason not to. Somewhere between 8000 and 9500 you would be likely to find the stock cranks limits. The piston speeds are also on the very high side though someone recently took an MRP crank with the same stroke over 1000 RPM and if I remember right over 1000 HP boosted. Those piston speeds will definitely take their toll though.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Mon Apr 20, 2015 6:15 pm

turboae92 wrote:
More torque which is better all around.


Torque means nothing till you apply RPM. At which point you are talking about power.
The 7A will generally give you a bigger and broader power curve.

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Mon Apr 20, 2015 6:23 pm

There's a guy here in Florida near me who's making over 500 hp atw over 600 at the crank.Its a 7age forged piston, rods, gt35 turbo, aluminum manifold, 3" exhaust, stock cams and Honda p28 computer.Check his setup out at youtube holdmywetnutz.

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Mon Apr 20, 2015 7:04 pm

yoshimitsuspeed wrote:
turboae92 wrote:
More torque which is better all around.


Torque means nothing till you apply RPM. At which point you are talking about power.
The 7A will generally give you a bigger and broader power curve.


I said that cause he wants to know the advantages over 4a.The 1.6l lack on torque even me with high compression and mild moderate boost.For all motor setup yes I would be worried about running the crank at 10k and piston speed will be high just like yoshimitsuspeed stated.But for mild build with 8-8.5k rev limit I wouldn't worry so much.I seen some ae86 videos over in Japan with 1.8l doing good.

jinx
Club4AG Expert
Posts: 334
Joined: Fri Jan 11, 2013 10:20 pm

Re: What's good about the 7age?

Postby jinx » Mon Apr 20, 2015 7:45 pm

bigger displacement gives you more torque, period. No need to mention rpm to communicate that

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Mon Apr 20, 2015 8:52 pm

turboae92 wrote:
yoshimitsuspeed wrote:
turboae92 wrote:
More torque which is better all around.


Torque means nothing till you apply RPM. At which point you are talking about power.
The 7A will generally give you a bigger and broader power curve.


I said that cause he wants to know the advantages over 4a.The 1.6l lack on torque even me with high compression and mild moderate boost.


By torque you mean low end power. Torque is irrelevant to determining acceleration so it really doesn't matter how much torque a motor makes. What matters is power and power curve.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Mon Apr 20, 2015 8:53 pm

jinx wrote:bigger displacement gives you more torque, period. No need to mention rpm to communicate that


I would agree that generally all other things being equal more displacement would increase the torque but that does not ensure it's a benefit until you give that torque an RPM and can calculate power.

jinx
Club4AG Expert
Posts: 334
Joined: Fri Jan 11, 2013 10:20 pm

Re: What's good about the 7age?

Postby jinx » Tue Apr 21, 2015 4:18 am

Torque is irrelevant to determining acceleration so it really doesn't matter how much torque a motor makes.

if that were true, 7000 pound duallys would need nothing more that a 1.0L in its glovebox..... as well as every other vehicle
No engine swap would exist, ever.
You need more torque to move (accelerate) more weight, period. Look around

Riddle me this.....
Two real world examples with optimal gearing and driver seat time
A 2.3 ford & 5 speed swapped into a 1st gen rx7, weighs 2740 full wt street car. 420hp / 440 ft-lbs tq. ETs 10.8 sec
A 420 hp CA18det 5spd in full wt 200sx/silvia, same wt. Will never see a 10.8 ET, ever..... or the same 440 tq at tires

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 9:09 am

jinx wrote:
Torque is irrelevant to determining acceleration so it really doesn't matter how much torque a motor makes.

if that were true, 7000 pound duallys would need nothing more that a 1.0L in its glovebox..... as well as every other vehicle
No engine swap would exist, ever.
You need more torque to move (accelerate) more weight, period. Look around

Riddle me this.....
Two real world examples with optimal gearing and driver seat time
A 2.3 ford & 5 speed swapped into a 1st gen rx7, weighs 2740 full wt street car. 420hp / 440 ft-lbs tq. ETs 10.8 sec
A 420 hp CA18det 5spd in full wt 200sx/silvia, same wt. Will never see a 10.8 ET, ever..... or the same 440 tq at tires


Actually a 1 liter motor would move a 70000 lb dually just as well as long as it made enough power and had the right gearing.
They are not used for this application because it would need to spin to 18k RPM, would need rebuilds ever 500 miles, would need to rev that high to get started which would kill clutches like nothing else. That increase in input side trans RPM would be harder on the gearbox as well.

The only thing wrong with your examples is that you are using torque to try to explain power curve. This is standard in the car world but that does not make it correct.
You lastly mention torque at the tires and that is what it all comes down to. As long as you have enough power to multiply and the proper gear multiplication you can make whatever torque at the wheels you want. On the other hand if you have torque without RPM you can't do anything.

http://matrixgarage.com/content/think-y ... -and-power

ogdougynutty
Club4AG Enthusiast
Posts: 134
Joined: Thu Jan 24, 2013 9:07 am

Re: What's good about the 7age?

Postby ogdougynutty » Tue Apr 21, 2015 9:27 am

Jinx i would just stop now, yoshi is about as bull headed as they come (never seems to be wrong) lol what a joke.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 10:19 am

ogdougynutty wrote:Jinx i would just stop now, yoshi is about as bull headed as they come (never seems to be wrong) lol what a joke.


When mathematicians, engineers and physicists agree with me and the only people who try to argue with me can't use math, science or physics to argue a legitimate counterpoint I don't see the joke.

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 12:49 pm

Yes the bigger displacement will mean higher torque figure at lower rpm.The 7afe makes 100 ft tq at 2800 rpm on the other hand 4age makes 100 ft at like 4000 rpm.Lets not get complicated with equation or mathematics cause at the end his not an engineer to figure out thing by himself, including myself.

User avatar
oldeskewltoy
Club4AG MASTER
Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

Re: What's good about the 7age?

Postby oldeskewltoy » Tue Apr 21, 2015 12:58 pm

yoshimitsuspeed wrote:
ogdougynutty wrote:Jinx i would just stop now, yoshi is about as bull headed as they come (never seems to be wrong) lol what a joke.


When mathematicians, engineers and physicists agree with me and the only people who try to argue with me can't use math, science or physics to argue a legitimate counterpoint I don't see the joke.


Image


as always... you tend to confuse the issue instead of clarify it. For purposes of comparing similarly built 4AG to a 7AG...

jinx wrote:bigger displacement gives you more torque, period. No need to mention rpm to communicate that
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 1:00 pm

turboae92 wrote:Yes the bigger displacement will mean higher torque figure at lower rpm.The 7afe makes 100 ft tq at 2800 rpm on the other hand 4age makes 100 ft at like 4000 rpm.Lets not get complicated with equation or mathematics cause at the end his not an engineer to figure out thing by himself, including myself.


So people should just use improper terminology because they aren't engineers?

Your example is perfect. 100 lb ft at 2800 is 53 hp.

100 lb ft at 4000 rpm is 76 hp.

The 4AGE at 4000 RPM will out accelerate the 7A at 2800 RPM by a significant amount.

Let's say the 7A is spinning the wheels at 2800 RPM at a 1:1 gear ratio and 100 lb ft of torque. The 4A would need a 1.42:1 gear reduction to spin the wheels at the same speed. Now it would be applying 140 lb ft of torque to the wheels and therefore would accelerate 40% faster.

Why are you arguing something that you just admitted you don't understand?

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 1:03 pm

oldeskewltoy wrote:as always... you tend to confuse the issue instead of clarify it. For purposes of comparing similarly built 4AG to a 7AG...

jinx wrote:bigger displacement gives you more torque, period. No need to mention rpm to communicate that


That's why I made the test above. It seems to do a lot better job of explaining the theory and misconceptions better than I do.
After taking the test very few continue the argument.
The only reason I confuse the issue is because people have such a deeply rooted misconception of this subject. When someone adamantly wants to believe the world is flat you will greatly confuse the issue when you start trying to make them believe it is not.

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 1:23 pm

I don't know know about much about formulas I do know that I been tinkering about with 4age for ten years from all motor,low compression turbo setup, to high compression turbo.Few have an ae92 like I do.What I don't like is you throwing all those formula and big words to explain something that can be easily explained.

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 1:41 pm

I don't know who said anything about acceleration has to due with torque????You makeup worlds that no one has typed. All I said 7age will make more torque at lower rpm which the 4age lacks of.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 1:51 pm

turboae92 wrote:I don't know know about much about formulas I do know that I been tinkering about with 4age for ten years from all motor,low compression turbo setup, to high compression turbo.Few have an ae92 like I do.What I don't like is you throwing all those formula and big words to explain something that can be easily explained.


The Op asked why the 7A would be better. You responded.


turboae92 wrote:I said that cause he wants to know the advantages over 4a.The 1.6l lack on torque even me with high compression and mild moderate boost.



turboae92 wrote:More torque which is better all around.


So with or without using math or technical terms please explain how more torque is better all around?

turboae92 wrote:I don't know who said anything about acceleration has to due with torque????You makeup worlds that no one has typed. All I said 7age will make more torque at lower rpm which the 4age lacks of.

If we aren't talking about acceleration then what are we talking about?
Again why is more torque better? What is the torque doing and how is that benefiting you?

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 1:56 pm

More torque feels better.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 2:05 pm

Image

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 2:10 pm

Please to make you feel better give us some that mathematics equation on what's better about torque.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 2:13 pm

How does more torque feel better if it doesn't have anything to do with acceleration?

All that matters is torque at the wheels. Torque at the wheels dictates acceleration. Acceleration dictates "feel".
A motor making 10000 lb ft of torque at 100 RPM will accelerate and "feel" the same as a motor making 100 lb ft of torque at 10000 RPM then run through a 10:1 reduction gear box because both will be applying the same amount of torque at the same RPM on the output side.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 2:15 pm

turboae92 wrote:Please to make you feel better give us some that mathematics equation on what's better about torque.


Torque is a force applied. You can stand on a torque wrench but until it starts moving it is not doing any work. The force applied doesn't mean anything until you apply a rate at which it does it.

Did you take the quiz? Did you pass?
Did you read through the answers in the end?

http://matrixgarage.com/content/think-y ... -and-power

turboae92
Club4AG Enthusiast
Posts: 93
Joined: Tue Feb 19, 2013 4:17 pm
Location: miami fl

Re: What's good about the 7age?

Postby turboae92 » Tue Apr 21, 2015 2:23 pm

Thanks.i did take it when you first made it and I failed by 4 answers.

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 2:26 pm

turboae92 wrote:Thanks.i did take it when you first made it and I failed by 4 answers.


Well if you still think that torque means anything without RPM I guess there is no hope.

User avatar
oldeskewltoy
Club4AG MASTER
Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

Re: What's good about the 7age?

Postby oldeskewltoy » Tue Apr 21, 2015 2:29 pm

yoshimitsuspeed wrote: You can stand on a torque wrench but until it starts moving it is not doing any work.


I know... I'm splitting hairs... but unless you are in a weight-less atmosphere by standing on the wrench the energy of your mass on the wrench is "moving" the wrench.

it might be better to explain it as until there is some force applied, there is no work being accomplished


BUT.... This doesn't answer the OP's post... which, you did rather well before this thread crumbled...


yoshimitsuspeed wrote:If done right (and I must stress that because so often it's not) it will gain you good power across the curve. It takes you from 1.6 liter to 1.8 liter. It's not a massive improvement but the cost to gain and as you mention the availability makes it pretty tempting.

I would say the only downside is that it limits the redline in extremely high RPM builds the stroke and it's effect on piston speed means you wouldn't want to put it in a 12k RPM screamer. It's also not real well defined on just how much the stock crank can take because not many have pushed it past it's limits.
On the other hand for an 8000 RPM or less build there really isn't any good reason not to. Somewhere between 8000 and 9500 you would be likely to find the stock cranks limits. The piston speeds are also on the very high side though someone recently took an MRP crank with the same stroke over 1000 RPM and if I remember right over 1000 HP boosted. Those piston speeds will definitely take their toll though.
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

yoshimitsuspeed
Club4AG MASTER
Posts: 2084
Joined: Sun Jan 13, 2013 1:18 pm
Contact:

Re: What's good about the 7age?

Postby yoshimitsuspeed » Tue Apr 21, 2015 2:44 pm

oldeskewltoy wrote:
yoshimitsuspeed wrote: You can stand on a torque wrench but until it starts moving it is not doing any work.


I know... I'm splitting hairs... but unless you are in a weight-less atmosphere by standing on the wrench the energy of your mass on the wrench is "moving" the wrench.

it might be better to explain it as until there is some force applied, there is no work being accomplished



Not necessarily. If that force is enough to break the bolt loose then the torque wrench will start moving. Put my 200 lbs on a 24" breaker bar and that 400 lb ft of torque will quite likely break the bolt loose on an AW11 or AE86. At which point I am doing work.
On the other hand put me standing on that 24" breaker bar on the lug nut of a 5 yard front end loader and that bolt isn't going to move. Just standing on that breaker bar does not mean I am doing any work. I am just standing there. Even though 400 lb ft force is being applied no work is being done.

Now let's make that breaker bar horizontal so I have to run around in a circle to spin the butchers sharpening stone.
Let's say I can push with 10 lbs of force. On that 2' breaker bar I can create 20 lb ft of torque to spin his stone.
Now give me a 20 foot breaker bar. I can now apply 200 lb feet but I have to run around a much bigger circle. Assuming I run at the same speed it will take 10 times longer to do a complete revolution.
With either the same amount of work would be being done and with the right gearing you could use either to apply the same torque and RPM to the butchers stone.

MtLemmon86
Club4AG Enthusiast
Posts: 83
Joined: Fri Oct 24, 2014 8:47 am
Location: Tucson, AZ

Re: What's good about the 7age?

Postby MtLemmon86 » Tue Apr 21, 2015 3:16 pm

I just bought one, getting it rebuilt this week when it's swapped in I'll post the before and after dyno. Hopefully it will simplify the decision for you, since this seems to have gotten a bit off topic.

Image
Image
Image

I did get the timing belt set up from matrix garage though so thank you for that.