twins vs last gen cayman?

[nikitopo]

Originally Posted by Tcoat

Proof?

There were corrective actions in '14 with bigger length intake & exhaust valves and changed cams and cam gears. This was found accidentally by a mechanic who was building an older engine and the new valves were not fitting and by myself independently while doing a complete comparison of part numbers. These changes provided a bit more aggresive timing and a gain of about 5-6whp. Cars of similar mileage on same dyno were giving this difference depending the manufacture year (pre- or post-change date). Strangely enough, these engines were not re-spec'd and never re-registered in the countries based on the changed internals. Your argument that companies are not allowed to do whatever they want is not always valid and history shows that there are still gray areas.

I am sure that Porsche cars have similar stories to share ...

[funwheeldrive]

Originally Posted by nikitopo

There were corrective actions in '14 with bigger length intake & exhaust valves and changed cams and cam gears. This was found accidentally by a mechanic who was building an older engine and the new valves were not fitting and by myself independently while doing a complete comparison of part numbers. These changes provided a bit more aggresive timing and a gain of about 5-6whp. Cars of similar mileage on same dyno were giving this difference depending the manufacture year (pre- or post-change date). Strangely enough, these engines were not re-spec'd and never re-registered in the countries based on the changed internals. Your argument that companies are not allowed to do whatever they want is not always valid and history shows that there are still gray areas.

I am sure that Porsche cars have similar stories to share ...

I heard about those minor tweaks, but I was under the impression that the changes didn't occur until MY15? Do you happen to have any dates for the changes?

[Tokay444]

Originally Posted by funwheeldrive

I don't know enough to make one claim either way, but I don't think I've ever seen a stock Zenki 86 put more than 170hp to the wheels on a dyno. And 170 is the high range, most seem to be around 165-168hp. Taking drivetrain loss into consideration, that's roughly 195hp at perfect conditions. The average car probably puts down closer to 190hp, which is pretty much what @nikitopo claimed.

No one but the driveline engineer can tell us what the drivetrain loss is.

[Tcoat]

Originally Posted by nikitopo

There were corrective actions in '14 with bigger length intake & exhaust valves and changed cams and cam gears. This was found accidentally by a mechanic who was building an older engine and the new valves were not fitting and by myself independently while doing a complete comparison of part numbers. These changes provided a bit more aggresive timing and a gain of about 5-6whp. Cars of similar mileage on same dyno were giving this difference depending the manufacture year (pre- or post-change date). Strangely enough, these engines were not re-spec'd and never re-registered in the countries based on the changed internals. Your argument that companies are not allowed to do whatever they want is not always valid and history shows that there are still gray areas.

I am sure that Porsche cars have similar stories to share ...

The fact that they changed some valves does not indicate an over rating of the engine. Even if it did the use of anecdotally evidence is not proof.
You are still relying upon dyno readings which are meaningless.

[funwheeldrive]

Originally Posted by Tokay444

No one but the driveline engineer can tell us what the drivetrain loss is.

Sure, that's why I used the word 'assuming' in my followup post.


edit- I'm not even sure what the point of this whole conversation was.

[WolfpackS2k]

Originally Posted by nikitopo

I am sure that Porsche cars have similar stories to share ...

Porsche loves to make mid model year changes all the time. Whenever I order parts online I have to enter the VIN # to guarantee that what I'm buying will fit.

[Tcoat]

Originally Posted by funwheeldrive

Sure, that's why I used the word 'assuming' in my followup post.


edit- I'm not even sure what the point of this whole conversation was.

The theory that the pre 17s HP numbers are grossly over rated and the post 17s are wildly under rated due to some weird conspiracy and cover up on Toyota's part.


There are a couple of people that truly believe that by bolting one or two 17 parts on their pre 17 they will get huge gains. So it is important that they convince everybody that the gains are actually there to be had.

[ZDan]

https://www.caranddriver.com/reviews...al-test-review
A Lot of Work for a 0.1-Second Gain
Predictably, a 5-hp gain and marginally shorter gearing do little to improve measured performance. Our 2017 test car hit 60 mph in 6.2 seconds and covered the quarter-mile in 14.8 seconds—improvements of 0.1 second across the board relative to the last manual BRZ we tested, a 2016 model. Trap speed remained the same at 95 mph.

[venturaII]

Originally Posted by ZDan

https://www.caranddriver.com/reviews...al-test-review
A Lot of Work for a 0.1-Second Gain
Predictably, a 5-hp gain and marginally shorter gearing do little to improve measured performance. Our 2017 test car hit 60 mph in 6.2 seconds and covered the quarter-mile in 14.8 seconds—improvements of 0.1 second across the board relative to the last manual BRZ we tested, a 2016 model. Trap speed remained the same at 95 mph.

ET is gearing, and trap speed is horsepower.

[DarkSunrise]

Originally Posted by funwheeldrive

I have never seen a stock Zenki 86 dyno showing 178hp or anywhere near there. Personally, from everything I have seen this car on average puts down closer to 190hp at the wheels than it does 200. Of course that's assuming a 15% drivetrain loss, and that's only what I've seen personally which doesn't mean much.

There's going to be a lot of variation based on specific dyno, weather, correction factors, etc. but FWIW my FR-S put down 177 whp with just a Perrin catback exhaust (arguably doesn't add any hp). Blue and green lines in the dyno below:



Moto-East dyno'd their BRZ at 175 whp stock:



And Edmunds dyno'd their FR-S at 173 whp stock (on CA 91 octane):

[nikitopo]

Originally Posted by funwheeldrive

I heard about those minor tweaks, but I was under the impression that the changes didn't occur until MY15? Do you happen to have any dates for the changes?

The valves were changed at 2013.5 for the MY14 cars. At first we found that these parts had different numbers and Tcoat insisted that there was no actual change and manufacturers/vendors constantly changing numbers. Then there was a comparison and the length was actual different. Everything is documented.

[nikitopo]

Originally Posted by WolfpackS2k

Porsche loves to make mid model year changes all the time. Whenever I order parts online I have to enter the VIN # to guarantee that what I'm buying will fit.

It wasn't during the mid model changes. In the majority of cases, they'll do changes to solve known issues. If it is for performance reasons they usually communicate it. I haven't heard anything about failed valves. It looks that the car was a bit rushed at the beginning and marketing was pushing a bit to achieve the magic 100ps/lt number. Anyway, this discussion does not lead anywhere so no reason to insist.


I still believe that Cayman is a much better car than a 86/BRZ. If I was to buy another sports car, for sure it would be one of the candidates

[Tcoat]

Originally Posted by nikitopo

The valves were changed at 2013.5 for the MY14 cars. At first we found that these parts had different numbers and Tcoat insisted that there was no actual change and manufacturers/vendors constantly changing numbers. Then there was a comparison and the length was actual different. Everything is documented.

No, I very clearly stated there could be several reasons for a part number change:
"Could be as simple as a supplier change or as advanced as a correction for a known issue or anything in between. Unfortunately we will not likely ever get a true answer to that question (there will be loads of speculation that people think is true though)
At work we can have a different part number on a part because the coating thickness spec changed by 2 microns."
Assuming that parts have changed based strictly on the numbers is a fools game.
NEWSFLASH - Parts also change and the number stays the same. That isn't even getting into the world of acceptable tolerance variations.


All that is "documented" is your opinion and speculation.


Even the guy that actually had come up against the changes got fed up with your theories being presented as facts:


"Alright so at the end of all this post what did we all learn......

1. At the end of production year 2013 Subaru increased the intake valve length to what it is on todays engines. Which I posted about a year ago.....

2.Internet software by Subaru has the same numbers as the disk version.....

3. Everyone who read this thread has lost 10 minutes of their life they will never get back................

Look this is over, you started this thread stating almost every valve train part is revised in 2015.
That is FALSE 100% FALSE!!!! I covered this a year ago, the change with adding the length to the intake valve happened in production 2014 Which means the valves were actually swapped in 2013 no major changes since...... The head number changed because they are assembled with the longer valves and supporting hardware. I'm not going to debate this any longer. IF you want to believe you have a super motor go ahead makes no difference to me... "

http://www.ft86club.com/forums/showthread.php?t=84282

[Tcoat]

Originally Posted by nikitopo

It wasn't during the mid model changes. In the majority of cases, they'll do changes to solve known issues. If it is for performance reasons they usually communicate it. I haven't heard anything about failed valves. It looks that the car was a bit rushed at the beginning and marketing was pushing a bit to achieve the magic 100ps/lt number. Anyway, this discussion does not lead anywhere so no reason to insist.


I still believe that Cayman is a much better car than a 86/BRZ. If I was to buy another sports car, for sure it would be one of the candidates

ALL cars receive incremental changes through their life. Just because they update parts does not mean they were "rushed", they made a mistake, or anything else deceitful. Prolonged use indicates some minor tweaks that can make things better and the manufacturers make those changes throughout the life of a model. It is endless and that is a good thing.