why im glad the brz doesnt have a turbo.

[keithr]

Originally Posted by perryair

hey keith - i've always been super interested in that kit and its good to hear some driving impressions. does it feel more like a spooling when it gets up into the meat of the powerband or is it just that the power feels like you get more incrementally the higher up in the rpm range?

i've also been following the edelbrock - its carb compliant and also hasthe 'whipple' design, which supposedly helps more with down low grunt. maybe one day i can find two to ride along with back to back.

I would say it's more of a linear pull than a turbo, but the idiosyncrasies of this particular engine mean you need to have some rpm going if you want the pull to be there. I don't drive around the city in traffic at 3500-4000. For those that do, the power is more immediate. For me, I have to accept that it's gonna dog a little bit or I get Popeye leg on the left from shifting 700 times per 1\4 mile in a typical Phoenix commute.

This is a daily driver for me, so these are the conditions. It would be a different ball game if I lived on the track with it.

I have a friend with a stock WRX. It FEELS faster, because the factory turbo has that almost logrythmic pull. It's certainly a little smoother at the bottom. It FEELS faster. It isn't. But it feels that way.

I'm no expert but from what I've heard the edelbrock is a trade-off.

I'm sure I could tune and re tune and re re tune every little nib and get it "there" -- but I liked that the JR tune is carb compliant since I'm near CA. I could sell the car to someone in CA or I could move there etc. The "premier" local shop f'd my car up once and were a bunch of smug jagoffs -- very dismissive of me. I suppose had I been spending 10k or driving a European car I would have been treated better since that's exactly what I observed there.

I don't want to spend every waking minute wrenching and messing with tunes. I went for the JR because of its advertised basically "plug and play" nature.

I don't want to hijack this thread any worse so we can take this to private chat or a different thread if you want more info on my impressions. 😀

*edit:. Hah! I didn't realize you were the OP. Hijack away!



Sent from my Nexus 7 using Tapatalk

[keithr]

Originally Posted by menikmati

This is the first "eh" sounding comment regarding the JRSC I've seen on this forum and the kit is regarded as one of the best superchargers.

I suspect my personal criteria don't match everyone's. I'm not saying it's not a great, or even the best kit, just that personally I'm not blown away by the overall experience the way I'd hoped I'd be. Forgive the pun.

Sent from my Nexus 7 using Tapatalk

[bcj]

Originally Posted by DAEMANO

These are relatively simple devices that require little maintenance, add next to no weight (unlike a traditional SC), and don't introduce heat in the same way either a turbo or S/C does when used as a single induction device.

The added heat is produced by compressing air. That has to go somewhere.
Electric motors produce heat as a byproduct of operation.
The battery produces heat when it discharges... and recharges.
The alternator produces heat charging the battery.

Pays yor monies and takes yor chance.
Not the *same* way, but way none the less.

[DAEMANO]

Originally Posted by bcj

The added heat is produced by compressing air. That has to go somewhere.
Electric motors produce heat as a byproduct of operation.
The battery produces heat when it discharges... and recharges.
The alternator produces heat charging the battery.

Pays yor monies and takes yor chance.
Not the *same* way, but way none the less.

Added heat from traditional turbos are also produced by routing hot exhaust gasses through piping in the engine bay. With traditional S/Cs, from mechanical friction throughout the system.

ESC's produce significantly less heat from the processes you've listed above. So little in fact that coolant temps under the bonnet while at speed anecdotally are roughly equivalent to my N/A car.

Certainly additional heat is there, but this is not even close to an equivalent situation when talking about ESC vs SC or Turbo. For the purposes of torque fill, there is very little drawback with the ESC route.

[Poodles]

Long post incoming...

Originally Posted by perryair

torque dip and turbo spooling is not the same thing - i know that if i give it 50% throttle what i can expect, dip included. if i give the turbo car 50% throttle, i get some type of 'wave' of power of which im not quite sure how much its getting into boost. again, its a lot of fun but its not a ton of predictable. if thats what you like, awesome. i happen to like it less than an na or even a supercharged setup.

I know it's not the same thing, but from a dead stop, it feels the same as an old factory turbo car with lots of lag and doesn't make any power until 5K RPM.

Originally Posted by turtlefeeder

I get what you mean but this is what I want to know.

if the car has torque dip at 3.5-5k rpm and mph goes up at a certain rate on stock motor. If I add a turbo will the rate of mph get worst or will it only get better with a small turbo

Depends on the size of the turbo. Too big and it's not going to kick in until 5K RPM. A nice small sized turbo should eliminate it.

Originally Posted by Xxyion

The torque dip in the 86 cars was put in in order to improve Economy. Adding a turbo will increase your top speed. It will also increase torque. As far as i understand it. Horsepower = Top Speed (how fast can you go), Torque = How quick can you get to your top speed. Generally adding a turbo also increases torque. A lot of people boost their cars less for the overall power and more for the torque that they get.

There are also ways around this like Tuning your car or adding aftermarket mods like Exhaust, headers, lighter wheels.

In the end its up to you what you want. I'm keeping my car engine stock and not boosting at all. From my own calculations and theory crafting i'm pretty sure i can hit the kind of torque and hp that would make me happy with other mods.

Torque dip isn't for economy. It's a byproduct of a number of things, and it's very common on boxer engines (Porsches have the dip too).

Originally Posted by turtlefeeder

good info, but I already got that. it still doesn't answer my question. how do I put this..

let's say in theory we have one frs/brz (call it car A) 200hp 2.0 and a frs/brz (car B) turbo charged

car A torque dips 3.5-5k rpm
now the question is would car B also get this torque dip and would that turbo help getting rid of that dip or will it still dip+turbo lag?

further more if the turbo cures the torque dip on car B would it just be replaced by turbo lag say. for example
if car B no longer has torque dip at 3.5-5k rpm but turbo now will it have turbo lag somewhere else In rpm range?

Depends on size of turbo. Also, there's really two types of lag:

1) RPM spool up: Where you're too low RPM and you're simply not going to spin the turbo fast enough to produce boost. Size of turbo and intake/exhaust help this (as well as something like a 2-step, but that's really for drag use)

2) Transient lag: Where you're on and off the throttle. Let's say you downshift into the power and it's that lag while the turbo spins up and fills the charge pipes. Generally speaking, this can be heavily effected by turbo design, antilag, bypass/blowoff valves, etc.

Originally Posted by perryair

and contrary to what some other people think - there is no turbo setup in a production car that has ever managed to have no lag or spooling at any throttle increment in all driving conditions. at least with today's technology its not possible even when you're bmw, mercedes, ford and others with "B"illions of dollars to throw around on R&D. turbo = lag however much its minimized with technology - you have to develop exhaust first in order to pump it back into the engine to develop vacuum and boost.

so there are two separate things youre talking about that have fairly little to do with each other.

Newer Porsche 911 would like a word with you...

Originally Posted by DAEMANO

Added heat from traditional turbos are also produced by routing hot exhaust gasses through piping in the engine bay. With traditional S/Cs, from mechanical friction throughout the system.

ESC's produce significantly less heat from the processes you've listed above. So little in fact that coolant temps under the bonnet while at speed anecdotally are roughly equivalent to my N/A car.

Certainly additional heat is there, but this is not even close to an equivalent situation when talking about ESC vs SC or Turbo. For the purposes of torque fill, there is very little drawback with the ESC route.

The primary reason is simply the compression of the air. The ESC doesn't put out enough to compare...



Also, it's a very basic point, but a turbo is more efficient and "passive" compared to a supercharger that takes power from the motor to spin. This is why some supercharger setups can feel like dogs in low RPM even compared to factory cars.

There is no silver bullet to all this, there's trade offs to everything. I'd really have to go a bit too far in depth to explain each system, but here's the simple breakdown

Bigger engine = more displacement = more power

Turbo = Displacement on demand (small engine out of boost, big engine in boost)

Centrifugal Supercharger = essentially a belt driven turbo with better transient response (and wildly varying efficiency levels)

Positive Displacement Supercharger = Roots style or variation thereof. Acts like a big engine all the time as the engine is always ingesting more air.

Electric Supercharger = Turbo driven by a motor that to date is really good at instant torque but falls off up top. Might be the silver bullet when combined with something else...


Disclaimer: Yes I know these are super dumbed down explanations and are missing many nuances.

[mav1178]

Originally Posted by perryair

turbo = lag however much its minimized with technology - you have to develop exhaust first in order to pump it back into the engine to develop vacuum and boost.

Today I learned I must produce exhaust gases to get vacuum.

[perryair]

Originally Posted by keithr

I would say it's more of a linear pull than a turbo, but the idiosyncrasies of this particular engine mean you need to have some rpm going if you want the pull to be there. I don't drive around the city in traffic at 3500-4000. For those that do, the power is more immediate. For me, I have to accept that it's gonna dog a little bit or I get Popeye leg on the left from shifting 700 times per 1\4 mile in a typical Phoenix commute.

This is a daily driver for me, so these are the conditions. It would be a different ball game if I lived on the track with it.

I have a friend with a stock WRX. It FEELS faster, because the factory turbo has that almost logrythmic pull. It's certainly a little smoother at the bottom. It FEELS faster. It isn't. But it feels that way.

I'm no expert but from what I've heard the edelbrock is a trade-off.

I'm sure I could tune and re tune and re re tune every little nib and get it "there" -- but I liked that the JR tune is carb compliant since I'm near CA. I could sell the car to someone in CA or I could move there etc. The "premier" local shop f'd my car up once and were a bunch of smug jagoffs -- very dismissive of me. I suppose had I been spending 10k or driving a European car I would have been treated better since that's exactly what I observed there.

I don't want to spend every waking minute wrenching and messing with tunes. I went for the JR because of its advertised basically "plug and play" nature.

I don't want to hijack this thread any worse so we can take this to private chat or a different thread if you want more info on my impressions. 😀

*edit:. Hah! I didn't realize you were the OP. Hijack away!



Sent from my Nexus 7 using Tapatalk

are you on the c38 rotor or the c30 one? does the sub 3500rpm feel at least smooth if not powerful? or is the power delivery lumpy down there? this is my weekend warrior car so im typically driving in the city a gear different than what would be 'normal' but i still want the accelerating experience to feel as linear as possible.

even though you had it installed, was it a fairly painless process for them? did you do any other work - replacing injectors or anything or was it straight plug and play?

[perryair]

Originally Posted by mav1178

Today I learned I must produce exhaust gases to get vacuum.

today i learned that no matter what you write on the internet, and how much you say that its your opinion, and how much you say that people can feel free to have a different opinion and that its fine, someone will eventually express the fact that they are a troll at their very core. congrats - you are what make the internet awful and forum boards a stupid place to try to express anything.

good job.

[perryair]

Originally Posted by Poodles

Newer Porsche 911 would like a word with you...

im not the kind of guy thats been lucky or rich enough to drive a porsche 911 but even according to its engineers:

"Under intense questioning, one of the Porsche engineers admitted that at 1800 rpm, the engine needs three full seconds to produce full torque from a closed throttle, though he was quick to add that the turbo lag dropped to two seconds at 2000 rpm and only one second at 2300. If a bit of turbo lag at very low revs is the price for a 7500-rpm redline charge, I think most of us will happily pay it."

http://blog.caranddriver.com/tech-di...urbo-flat-six/

im sure that it feels joyous and wonderful and i would trade a new turbo 911 for my brz in a heartbeat, but still it remains that there is some lag there.

[nikitopo]

Turbos are something trendy in our days and unfortunately a necessity mainly for reasons of consumption and CO2 regulations. Turbos were known for many many decades, but most manufacturers took them seriously maybe after the late 90s. Some of the biggest manufacturers have admitted that there isn't anything serious about them, but unfortunately most of them are leaving behind their NA designs. At least for the time being. I believe we are lucky that our cars were designed as NA. Of course, both companies are paying for years the price of such decision. I'm not opposed to more power, but for me it matters how you get it. Personally, I am interested to see the potential of our engines with better intake manifolds, better engine management, stroker kits, than just throwing a S/C or a turbo.

[darthpnoy1984]

I don't mind if the car gets a little extra .5 liters at 240-250 NA it would be sufficient enough.


Sent from my iPhone using Tapatalk

[Lantana frs]

This car was designed for 200 crank horsepower and not much torque. With a 93 octane tune and cpb,s the tires are barely sufficient imo.

[W129]

Originally Posted by mav1178

So you don't want a turbo on the FA20 to not mess up the precision of the car.

And you want a supercharger.

Got it.

I have owned 4-5 turbo cars in my life, everyone I learned how to stay in boost, so set that aside.

I have never driven or liked positive displacement super chargers.

Let's talk centrifugal superchargers.

If you have never driven a Rotrex Supercharged car, you don't know what you're missing. I have a 99 Miata (4 years)with a Rotrex C30-74 @ 8psi inter-cooled (120RWHP to 220RWHP). Most people who have driven or driven with me, do not know it has a supercharger. I am more likely to hear " I didn't know Miata's were this fast.

It feels more like a bump in displacement, it's just faster, pulls a little harder. Slightly higher exhaust note.

If you look at the dynos, you see very similar curves, just moved up the graph. Very easy to control on the track and street. This is exactly what I want for my 86.

A proper factory turbo (spools at 2500, holds boost to fuel cut) with a drive train to match would be a great option

[perryair]

Originally Posted by W129

I have owned 4-5 turbo cars in my life, everyone I learned how to stay in boost, so set that aside.

I have never driven or liked positive displacement super chargers.

Let's talk centrifugal superchargers.

If you have never driven a Rotrex Supercharged car, you don't know what you're missing. I have a 99 Miata (4 years)with a Rotrex C30-74 @ 8psi inter-cooled (120RWHP to 220RWHP). Most people who have driven or driven with me, do not know it has a supercharger. I am more likely to hear " I didn't know Miata's were this fast.

It feels more like a bump in displacement, it's just faster, pulls a little harder. Slightly higher exhaust note.

If you look at the dynos, you see very similar curves, just moved up the graph. Very easy to control on the track and street. This is exactly what I want for my 86.

A proper factory turbo (spools at 2500, holds boost to fuel cut) with a drive train to match would be a great option

hey, thanks for sharing your non - agreeing opinion like a regular person. im sure that i could love turbos too, its hard for me to get over the spooling but i'm sure like you said its something you can learn to control.

i've driven an old f-150 lightning with a screw type supercharger and that thing was an animal, but thats a sc sitting on top of an 8 cyl engine. i've typically heard good things about the centrifugal style ones as well, but there was a commenter on here who didn't really love his jrsc setup on the brz.