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Petrus
(@petrus)
Estimable Member

I know, either lightweight or underdrive, it does not liberate more power. It doés make for a livelier engine even if ever so marginally by reducing rotational mass. The perspective is that a 2ZZ nor turbo is an option here so marginal is all there is. The other perspective is that my car is down to 900 kilos ready to go.

Fitted the MRW underdrive alternator one and am happy with it. 

At the time also looked at a lightweight crank pulley but was flummoxed by the interweb ´experts´ unceremoniously mixing harmonic damping, harmonic balancing and different engines.

Since then have seen wobbly OEM ones (on Corolla and RAV) and noted that it will not do a lot of harmonic damping on the 1ZZ crank.

I am ok with the outlay, I know the effect is marginal and am ok with that too. The crux is; what is the problem if there is one? What is the opinion over here?

 

 

 

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Posted : February 21, 2020 6:09 pm
dev
 dev
(@dev)
Just a member. Moderator

Years ago there was this guy who wasn’t too bright that argued in favor of the under drive crank pulley when it was a controversial modification.  As time went on he tried to convince others to do the same and said nothing would go wrong and that the manufacture adds the harmonic balancer but it’s not really needed.  
Eventually he spun a bearing after a year and when he was told by the community that he was foolish he called them all idiots because no damage happened to the under drive pulley. 

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Posted : February 21, 2020 7:32 pm
Petrus
(@petrus)
Estimable Member

@dev

The Toyota pulley is an harmonic damper and not a particularly hefty one. I can understand that the longer stroke of the 1ZZ will make the cast! crankshaft more prone to flex and as such the damper functional.

For one Toyota engineers will not fit one if not needed. On the other they will fit common parts not necessarily right on for a specific application. You mentioned the 1ZZ water pump as an example; probably overkill on the MR2 but needed for other front engine layouts and parts commonality has a priority too.

Those spun bearings, was that on a 1ZZ?

 

 

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Posted : February 21, 2020 7:55 pm
dev
 dev
(@dev)
Just a member. Moderator
Posted by: @petrus

@dev

The Toyota pulley is an harmonic damper and not a particularly hefty one. I can understand that the longer stroke of the 1ZZ will make the cast! crankshaft more prone to flex and as such the damper functional.

For one Toyota engineers will not fit one if not needed. On the other they will fit common parts not necessarily right on for a specific application. You mentioned the 1ZZ water pump as an example; probably overkill on the MR2 but needed for other front engine layouts and parts commonality has a priority too.

Those spun bearings, was that on a 1ZZ?

 

 

Yes it was but that’s  is not the point. It is the engine design that calls for it not the application it’s in. Either way I would not entertain anything under driven and not harmonically ballanced  for a street car or anything non OEM when it comes to parts like this because the devil is always in the details.  
Most of us are not engineers to theorize the many unknowns that can lead to a catastrophic failure.  I do know Toyota runs extensive failure testing and even the most minor thing can lead to disaster like what Toyota is going through right now with their latest engine recall.
 
Which ever side of the argument you side with the safest one is where you don’t mess with the engineering science. Being conservative in this regard saves you a lot of headache and heartache.

Most of these type of mods are made for racing where engine longevity is not as much of a concern compared to qualifying, running a race and dumping the engine.  Unless you are being sponsored it’s not worth it. 

Im not saying not to do it. If you feel that it’s safe by all means go for it and find out for yourself. I certainly wouldn’t do it because I don’t have the time or expense of replacing a perfectly good working engine. 
If I had a 1ZZ I would just save up and move up to real performance than bet the farm for something that feels like less than a lightweight flywheel. 

Even with a mod like a lightweight flywheel it has its own risks which a local owner got the short end of the stick due to a widely known failure. Most people think there is always a free lunch without any drawbacks but that’s not how it works in the real world of ownership but the fantasy lives on in car forums and MWR marketing. 

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Posted : February 21, 2020 9:06 pm
dev
 dev
(@dev)
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 I had to find an old thread where Matt from MWR has claimed that he had noted the un-dampened light weight pulley from his anecdotal  observations has taken out oil pumps and destroyed cranks in both 1ZZ and 2ZZ motors.  

 Problems with modifications like these is you cant eye ball and make your own engineering fit your optimism. Just because a part is light, off center or looks like it doesn't do much is not the best way to judge a parts effectiveness.  The rubber damper is probably worked out using sophisticated engeeneiqng where they are able to tune it like a fork to take the stress off the crank pulley by dissipating specific destructive harmonics. 

 Its an interesting discussion and food for thought like anything but these devices have been noted across the board for failure on multiple platforms.  Even if there was an aftermarket company that made a light weight dampened pulley I still would not trust it because it might not be tuned well enough like the OEM.  

 There have been examples of modifications that people upgrade to for the sake of making their car better but it has ended up in failure as a result because the parts were not engineered perfectly. These small aftermarket companies do not have the facilities or the expense to run failure testing like the OEM.  

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Posted : February 22, 2020 1:06 am
Petrus
(@petrus)
Estimable Member

@dev

Sticking to OEM is the best compromise. Period. No discussion there.

Modifications cán however give gains. Take the downpipe. It gives quite a nice gain in power although at the illegal price of deleting the cat.

A decat manifold is a different example. Slightly better flowing, deleting a potenstial issiue and .... illegal.

And then there is Cap Weir´s MAF mod.

As to harmonic balancers/dampers there is no sense in buying after market ones as those are never so well matched as the OEM ones and a not perfectly in sync harmonic damper/balancer will than do more harm than a simple lightweight one.

Bottom line is that I will stay with the OEM one...

 

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Posted : February 22, 2020 3:10 am
dev
 dev
(@dev)
Just a member. Moderator

As to the downpipe  you can get a high flow cat versions that can be very effective as far as flow. Its still not a free lunch because it will not last as long as the OEM and it will be louder. These modifications can be troublesome with fitment and too much sound but at least you are not gambling your engine but on some cars you can if the engine runs too lean that a factory ECU has trouble compensating for.  Fortunately our cars have ECUs that have safeguards. One of the many reasons I ran from the power FC because you are trading short term gains for engine longevity and risk.   

  It basically comes down to picking your poison but some are far worse than others and the crank pulley is in that category because  of the marginal gains for engine damage goes against any rational logic. 

 I remember long ago a member that threw the kitchen sink into a 1ZZ engine had me test drive his car. He had a fully built motor with everything and I also believe the light weight crank pulley. When I drove it, it was peppy and responsive but it had its own quirks with him having to fiddle with the PFC tune and smelling like fuel and oil. Not soon after I did my 2ZZ swap and for me it was spectacular the first time I hit lift and seen everything moving incredibly fast.  That 40hp even if its up top is real gains and a complete transformation. All these little mods to get out of your 1ZZ adds up in cost with marginal gains that is not worth it in both reliability and expectations. Im not putting down the 1ZZ as its a great engine but at its factory power its good enough not to be messed with and dump a whole lot of money into. Its better value to just save up for real undeniable gains.  

 

 

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Posted : February 22, 2020 9:14 am
dblotii
(@dblotii)
Trusted Member

@dev  Yes take it from a long-time engine engineer: the OEm harmonic damper is important for preserving the life of the crankshaft.  It is a torsional vibration damper.  There are certain engine speeds that yield very high torsional stress on the crank, and the damper reduces these worst-case speed conditions to safe for infinite life.  It is much safer to install larger alternator and water pump pulleys if you want to slow these accessories down.  If you want to reduce rotational inertia of the engine, go for a lighter flywheel.

 

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Posted : February 22, 2020 9:51 am
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Petrus
(@petrus)
Estimable Member
Posted by: @dev

That 40hp even if its up top is real gains and a complete transformation. All these little mods to get out of your 1ZZ adds up in cost with marginal gains that is not worth it in both reliability and expectations. Im not putting down the 1ZZ as its a great engine but at its factory power its good enough not to be messed with and dump a whole lot of money into. Its better value to just save up for real undeniable gains.  

 

 

Power wise the 2ZZ is a 1ZZ with an additional top end. It thus depends on your driving what you want. I´d rather have the extra oomph of forced induction but that is personal preference and hypothetical only; see below.

As I wrote several times, for me there ís no 2ZZ option as this is ever so difficult, not to say impossible, to get homologised. Unlike a decat downpipe that is not a thing you swap out for yearly inspection... Same thing forced induction; only a TTE kit would be possible to get entered in the vehicle docs and thóse are rather long in the tooth both in years and tech. I háve the money for a TTE kit if one would happen to come up for sale at a reasonable price. The saving up thus is not the issue but I simply think that a 15 y.o. TTE turbo is not a good idea. So there you have it. 

Thus 1ZZ and rational marginal gains it is. With the exhaust, MAF mod and little things I think I am just about at the limits of that; say 155 maybe a whiff more crank hp. Not going lighter flywheel as that has a driveability trade off I can do without.

All in all I think my car is about as good as it gets without spending silly money for limited gains. With that I mean more weight saving and at 900 kilos ready to drive now and as with the 1ZZ that gets silly when you get to carbon bonnet/engine lid et al so 900 it is. 

Mind you, 155/160 hp for 900 kilos is nice enough in the mountains 🙂

 

 

 

 

 

 

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Posted : February 22, 2020 3:45 pm
dev
 dev
(@dev)
Just a member. Moderator
Posted by: @petrus
Posted by: @dev

That 40hp even if its up top is real gains and a complete transformation. All these little mods to get out of your 1ZZ adds up in cost with marginal gains that is not worth it in both reliability and expectations. Im not putting down the 1ZZ as its a great engine but at its factory power its good enough not to be messed with and dump a whole lot of money into. Its better value to just save up for real undeniable gains.  

 

 

Power wise the 2ZZ is a 1ZZ with an additional top end. It thus depends on your driving what you want. I´d rather have the extra oomph of forced induction but that is personal preference and hypothetical only; see below.

As I wrote several times, for me there ís no 2ZZ option as this is ever so difficult, not to say impossible, to get homologised. Unlike a decat downpipe that is not a thing you swap out for yearly inspection... Same thing forced induction; only a TTE kit would be possible to get entered in the vehicle docs and thóse are rather long in the tooth both in years and tech. I háve the money for a TTE kit if one would happen to come up for sale at a reasonable price. The saving up thus is not the issue but I simply think that a 15 y.o. TTE turbo is not a good idea. So there you have it. 

Thus 1ZZ and rational marginal gains it is. With the exhaust, MAF mod and little things I think I am just about at the limits of that; say 155 maybe a whiff more crank hp. Not going lighter flywheel as that has a driveability trade off I can do without.

All in all I think my car is about as good as it gets without spending silly money for limited gains. With that I mean more weight saving and at 900 kilos ready to drive now and as with the 1ZZ that gets silly when you get to carbon bonnet/engine lid et al so 900 it is. 

Mind you, 155/160 hp for 900 kilos is nice enough in the mountains 🙂

 

 

 

 

 

 

  It is a common misconception that a 2ZZ is 1ZZ until 6k rpms.  These engines are completely different and have very different feel  to them including the gearing. The short stroke of the 2ZZ feels like something else entirely in its power characteristics.  Also its not about overall horsepower to gauge the fun factor as a high revving motor has its own charm with longer legs. 

      It is also a common misunderstanding that with bolt ons you can get the same power as a 2ZZ.  There have been all kinds of paper racers and various variables that show that when the NA 1ZZ with bolt ons is put on a dyno it fails terribly and is a disappointment because of false marketing and speed shops fudging the dyno graphs of various modifications.  If they make you happy then its money well spent but lets not kid our selfs. 

It is also a common misunderstanding to underrate the effectiveness of the 2ZZ once its set up with a proper intake and exhaust which only gets better once you reduce the weight of the car which makes it a fast car even by todays standards.  

 The 1ZZ fits a little better with its gearing to be far more forgiving as far as handling and the 2ZZ requires a bit more finesse to get the most out of it.  

  The bottom line is the 1ZZ is a dead end motor unless you go turbo or SC which is a great option that works well and with a conservative  tune of over 200hp and 180ftlbs of torque is a major transformation for this car period.  These little gains are not much if at anything at all but it keeps people buying until they need more once the honeymoon phase is over.  

 

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Posted : February 22, 2020 4:06 pm
Petrus
(@petrus)
Estimable Member

Not arguing Dev. There are simply no other options for me to me than 1ZZ, with an old TTE turbo kit as only legal add on. So marginal gains it is and I´ve reached the sensible end of that, both on the 1ZZ and lightenng the lot.

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Posted : February 22, 2020 4:16 pm
dev
 dev
(@dev)
Just a member. Moderator
Posted by: @petrus

Not arguing Dev. There are simply no other options for me to me than 1ZZ, with an old TTE turbo kit as only legal add on. So marginal gains it is and I´ve reached the sensible end of that, both on the 1ZZ and lightenng the lot.

    When I had my 1ZZ and it was mostly stock except for an intake and exhaust I was more then happy with it. The quest for more especially if its marginal will just blindside you trying to chase marginal gains. The best thing you can do is enjoy what you have. Many fall in this trap of trying to get every last bit which is fine but sometimes bolt ons can only do so much for some cars and the returns are dismal. 

 I could get a little more with my 2ZZ but I pulled back and at some point stopped. I also tried to lose more weight but im at an impasse of spending a fortune on a CF hood or reducing the street worthiness of the car.   I stopped until there is going to be a game changing modification like the Willwood calipers. Im not going to sweat the small stuff anymore and just enjoy what I have reliably.  

 Often times people convert their street cars into mini race cars for the street and then regret making it more hardcore then it once was and end up losing interest as a result.

 A friend of mine with a Turbo MR-S would ask people to trade cars with him for test drive as he actually enjoyed the stock Spyder. I asked him why and he said it was just more fun to drive it stock as he remembered it before going turbo. 

 

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Posted : February 22, 2020 4:36 pm
Petrus
(@petrus)
Estimable Member
Posted by: @dev

 

 Often times people convert their street cars into mini race cars for the street and then regret making it more hardcore then it once was and end up losing interest as a result.

 

Why do you think mine is on stock suspension 😉

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Posted : February 22, 2020 7:49 pm
marsrock7
(@marsrock7)
Reputable Member
Posted by: @dev

 Often times people convert their street cars into mini race cars for the street and then regret making it more hardcore then it once was and end up losing interest as a result.

This is a concern of mine regarding my eventual supercharger build. Im positive I will enjoy it when it is done, but suspect I will miss what the NA 2ZZ feels like, and end up driving the car less. Probably a second Spyder in my future.

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Posted : February 23, 2020 8:40 am
dev
 dev
(@dev)
Just a member. Moderator
Posted by: @marsrock7
Posted by: @dev

 Often times people convert their street cars into mini race cars for the street and then regret making it more hardcore then it once was and end up losing interest as a result.

This is a concern of mine regarding my eventual supercharger build. Im positive I will enjoy it when it is done, but suspect I will miss what the NA 2ZZ feels like, and end up driving the car less. Probably a second Spyder in my future.

  It has taken me a long time just getting use to the 2ZZ. The 1ZZ and gearing is better suited for the Spyder even though its slower. Most only look at straight line performance fun and not so much what it does in the turns as I always felt I was in-between two gears. Its very easy to bog a 2ZZ and miss your mark however you can use the longer legs to your advantage in terms of braking but its like murdering your engine at high revs before the turn and then trying to catch it in lift as you exit.  But there is nothing like going into 3rd gear and stretching it out because it keeps building and building though lift like a second stage booster. The sounds its makes is just intoxicating and when they made the reference in Ford vs Ferrari it it home.  

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Posted : February 23, 2020 10:12 am
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