Anyone coming from an STI?

NapalmEnema said:

Friend, with respect, I come from a long line of cars both RWD and AWD - the STi platform even with serious modifications is a stretch to say you had 700+ streetable and now are shooting for 900 streetable. It's just not feasible, and sounds a bit silly.

I mean come on friend, you're going to / and have been - driving more power on the daily - reliably - than Ken Block?

The car that Ken Block used in his first Gymkhana video was this Subaru Impreza WRX STI. Built by Vermont SportsCar and powered by a flat-four engine, this STI produces 565 horsepower

You may have a very generous dyno in your area, but I don't believe that you are rolling that then, or now, with respect.

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I love giving history lessons. The first Ken Block video was shot in what... 2008ish? This was at the same time that naysayers criticized the use of Nitrate Treated Crank shafts. I remember this because it was at the same time that Brian Crower (I believe) introduced thier Billet Subaru crankshaft (no longer available) which at that time cost me close to $4,000.00 (newly invented parts always cost more). I believe this is also the same time that I went off on my own to get a shop (that I won't disclose) to make me Diamond coated I Beam rods for my first built block (custom). In the end AR Fab sleeved the engine and put it together. Andrewtech later dyno'd this car at TurboXS in 2010 maybe... and it put down 668WHP on C16 with a Forced Performance HTAGT3788R. Thank you again to the team and people involved that helped pull this car together. It was a lot of work and I appreciated every drop of blood sweat and tears. That same block I later sold 3 years ago to a buddy here in Texas for his Subaru.... this block is still running strong in a daily 450hp WRX. This block shoes the quality of work that AR FAB produces. Fantastic work guys & girls.

While I'd love to continue to go down a rabbit hole with you, I cant and I won't. My new build once again has a lot of shops involded that at this time I cant disclose the names of and I cant get into specific parts that are being used as most of them are prototypes. I also cant disclose the purpose of this car or where you might see it next year competing.

FYI, I am not rich... just no kids. My wife's 280WHP 500 Abarth is our creation together.

In the End... lets stop high jacking this guys thread. GothemDrew asked for input on two cars. I gave him my modification experiences.

My apologies Drew... that wasn't my intention. I am done with my Troll slaying for today.

Again, I apologize for any grammatical issues.

Purple Drink said:

I love giving history lessons. The first Ken Block video was shot in what... 2008ish? This was at the same time that naysayers criticized the use of Nitrate Treated Crank shafts. I remember this because it was at the same time that Brian Crower (I believe) introduced thier Billet Subaru crankshaft (no longer available) which at that time cost me close to $4,000.00 (newly invented parts always cost more). I believe this is also the same time that I went off on my own to get a shop (that I won't disclose) to make me Diamond coated I Beam rods for my first built block (custom). In the end AR Fab sleeved the engine and put it together. Andrewtech later dyno'd this car at TurboXS in 2010 maybe... and it put down 668WHP on C16 with a Forced Performance HTAGT3788R. Thank you again to the team and people involved that helped pull this car together. It was a lot of work and I appreciated every drop of blood sweat and tears. That same block I later sold 3 years ago to a buddy here in Texas for his Subaru.... this block is still running strong in a daily 450hp WRX. This block shoes the quality of work that AR FAB produces. Fantastic work guys & girls.

While I'd love to continue to go down a rabbit hole with you, I cant and I won't. My new build once again has a lot of shops involded that at this time I cant disclose the names of and I cant get into specific parts that are being used as most of them are prototypes. I also cant disclose the purpose of this car or where you might see it next year competing.

FYI, I am not rich... just no kids. My wife's 280WHP 500 Abarth is our creation together.

In the End... lets stop high jacking this guys thread. GothemDrew asked for input on two cars. I gave him my modification experiences.

My apologies Drew... that wasn't my intention. I am done with my Troll slaying for today.

Again, I apologize for any grammatical issues.

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I like how you talk down to someone without doing any research what so ever to back up your claims -

https://www.motor1.com/features/273576/ken-blocks-cars-ranked/3348931/

This is the Subaru I was indicating, as I would not have chosen the oldest one in his stable for comparison sake.

I also owned a Subaru, a 2008 STi, and currently own a 2005 WRX, a 2017 M2, and a 2013 X5M. I've also owned, and modified, EVO's, mustangs, and even a vette somewhere in there as well. And I'm still straight up calling BS on your horsepower claims for multiple cars, just based on my hands on experience with the platform. On top of that you keep adding to it now - undisclosed shop with diamond coated beam rods. <heaviest of eye rolls here>

But wait - It gets better! You're not rich. Heck this is just a hobby! And I totally feel you there.

I remember when I was working second shift at Dairy queen and I thought to myself - I'm going to hit up my top secret modification shop and ask them to anneal some crazy materials together...hmm...something exotic <pours sprinkles> Tungsten? No...too 'basic' - Diamonds - that's it! I'll ping them on my next break.

I mean surely you can see how absurd you sound reading this stuff back to yourself? Secret shop? Diamond coatings? But not rich. Heck most people these days pal around in 800hp Subarus without mechanic bills on the horizon - why not!

#Makebelieveworld

I don't understand what is so unbelievable with the man's claims? It all seems legit to me. Nitrate treated is a heating process, used frequently in the industrial sector. I've seen it quite a bit. Just because his builds aren't all over the internet like everyone else's it doesn't mean they don't exist.

Edit: Apologies, I saw you were talking about the diamond coated rods. Diamond is extremely hard and has low corrosion rates which makes It desirable in some applications.

Sold my 2017 Sti to get a 2017 type r.

I loved being a part of the subie nation for a while. Every Subie owner is super friendly and we would throw peace signs at one another on the road.

Taking it to the track for HPDEs really let me see its weak points. The boxer engine is finicky and consumes oil like mad when youre in high g corners because of the way the g forces act on the oil. It pushes it into the valve cover and into the pcv system. Got a top of the line AOS from IAG but it still consumed oil.

It also overheated even with an oil cooler and upgraded radiator.

Sti is slower than the CTR because of the weight.

Steering feel in the sti is better because of the hydraulic ps.

The interior of the type R is much better. Adjustable dampening is a butt saver. Car Play is amazing. Seats are better. Inline 4 is easier to work on and you don't need to find experienced boxer mechanics. Residual value of the CTR is much better. I can probably sell it for MSRP if I wanted to. I sold the STI for a $4000 loss after a year and a half of ownership.

doctorbee said:

Sold my 2017 Sti to get a 2017 type r.

I loved being a part of the subie nation for a while. Every Subie owner is super friendly and we would throw peace signs at one another on the road.
.

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This is the biggest thing I miss about my STI. The Honda "community" absolutely sucks compared to the Subie fam.

hicompb18c1 said:

This is the biggest thing I miss about my STI. The Honda "community" absolutely sucks compared to the Subie fam.

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Perhaps there are enough of us Subie defectors to wave and be friendly.

doctorbee said:

Sti is slower than the CTR because of the weight.

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That's half of it. The other half is going to be the powertrain loss of AWD vs FF. The addition of a drive shaft and some mechanical coupling diverting power front and rear causes a considerable amount of power loss. Not only in the distance the power must travel, but the components it must run through. If I'm not mistaken, estimates for an FF, MR, and RR drivetrain loss is about 10%, FR is around 15%, and AWD is about 20%. The only exception to this would be an electric motor/hybrid system. In the NSX, for example, the gas motor would incur about 10% loss while the electric motors would see a slightly different loss.

So basically, take a 300HP motor and pair it with an FF and AWD powertrain, you can expect approximately 270HP at the wheels in the FF model while the AWD model sees only 240HP. Add in the additional weight of the AWD system and you swing both values in the power-to-weight ratio in the wrong direction by adding AWD.

The trade off you get with AWD is better traction in low traction situations and torque vectoring that doesn't require you to apply the brakes. The amount of traction available doubles in an AWD vehicle compared to an FF vehicle.

tinyman392 said:

That's half of it. The other half is going to be the powertrain loss of AWD vs FF. The addition of a drive shaft and some mechanical coupling diverting power front and rear causes a considerable amount of power loss. Not only in the distance the power must travel, but the components it must run through. If I'm not mistaken, estimates for an FF, MR, and RR drivetrain loss is about 10%, FR is around 15%, and AWD is about 20%. The only exception to this would be an electric motor/hybrid system. In the NSX, for example, the gas motor would incur about 10% loss while the electric motors would see a slightly different loss.

So basically, take a 300HP motor and pair it with an FF and AWD powertrain, you can expect approximately 270HP at the wheels in the FF model while the AWD model sees only 240HP. Add in the additional weight of the AWD system and you swing both values in the power-to-weight ratio in the wrong direction by adding AWD.

The trade off you get with AWD is better traction in low traction situations and torque vectoring that doesn't require you to apply the brakes. The amount of traction available doubles in an AWD vehicle compared to an FF vehicle.

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All good info, I'll just add one minor edit. Traction doesn't double with AWD because there is so much weight on the front of the CTR (62%) that you're really only increasing traction by about a factor of 1.5, maybe 1.6 or 1.7 in full acceleration on dry pavement, with AWD, not by a factor of 2 (when you accelerate, weight shifts to the back, but if you're in a low traction situation, it doesn't shift that much).

yargk said:

All good info, I'll just add one minor edit. Traction doesn't double with AWD because there is so much weight on the front of the CTR (62%) that you're really only increasing traction by about a factor of 1.5, maybe 1.6 or 1.7 in full acceleration on dry pavement, with AWD, not by a factor of 2 (when you accelerate, weight shifts to the back, but if you're in a low traction situation, it doesn't shift that much).

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I'm not sure how much the CTR will shift weight under hard acceleration. But we can kind of estimate it.

dW = (a/g)(h/b)m* where

Plugging in some numbers we get:


dW = (4.98m/s^2 / 9.81m/s^2) (0.36m / 2.7m) 3115lbs = 211 lbs or about a 7% weight transfer to the front. If you use the 0.48 measurement you get about 281lbs or about 9% weight transfer to the front. Using this we can compute the weight distribution of the CTR under hard acceleration to be about 55/45 to 53/48 under hard acceleration. In which case the increase in traction from FWD to AWD on the CTR is between 1.8 and 1.9 as low-ball estimates. I'd say it's pretty close to 2.

To be honest, I wouldn't be surprised if Honda did set up the CTR to have a perfect 50/50 weight distribution under heavy acceleration which is what this seems to suggest.

*https://en.wikipedia.org/wiki/Weight_transfer#Load_transfer
**Motortrend gives a 4.9 0-60 time, though in reality they start from a roll, so 5-60 would be a better approximation. If you go through the math, that's about 4.98m/s^2 average. If you compute 0-60 you get 5.44m/s^2 which increases the weight distribution as well. So again, low-ball estimate.
***Total height of the CTR is 1.44 meters high, I don't actually know the center of mass height, I'll guesstimate this to about ¼ to ⅓ the total height or about 0.36m to 0.48m, I personally feel like this is lower than it should be which gives a lower shift in weight. For reference, the Corvette C7 Z51 has a center of mass height of 17½" and a total height of 48.6" or about (36% of its total height), so both of these estimates are well below what the CTR might actually be.

1. Looks good to me. I suppose my larger point is that at full power in dry conditions it doesn't need more traction, but in the wet it might need more traction, and for those conditions the weight transfer would be smaller, but your calculation stands.

2. Physicist or engineer?

yargk said:

1. Looks good to me. I suppose my larger point is that at full power in dry conditions it doesn't need more traction, but in the wet it might need more traction, and for those conditions the weight transfer would be smaller, but your calculation stands.

2. Physicist or engineer?

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The CTR doesn't need more traction in the dry? Stock tires you can't go WOT in 1st or 2nd without spinning the fronts in the dry. It could use more traction, though there is a rewarding feeling when you learn how to acceleration well out of a stop.

Neither actually, math, CS, and data science background.

On PS4S tires I don't spin in 2nd at WOT, unless I just shifted from 1st, but it's usually not too cold here. Also, I think TC kicks in early so I get that often, but when I actually turn it off I don't spin in 2nd just accelerating out of corners. I suppose I meant lap times aren't largely traction limited on racetracks. Drag racing and AutoX I can see it being a factor.

Cool, nice to see equations on the forum!

yargk said:

On PS4S tires I don't spin in 2nd at WOT, unless I just shifted from 1st, but it's usually not too cold here. Also, I think TC kicks in early so I get that often, but when I actually turn it off I don't spin in 2nd just accelerating out of corners. I suppose I meant lap times aren't largely traction limited on racetracks. Drag racing and AutoX I can see it being a factor.

Cool, nice to see equations on the forum!

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I have heard that stickier tires do help the CTR out. I think I've heard people say that the PZEROs give no spin anytime which is crazy. You are absolutely right though that on track or autoX the traction isn't a factor.

Equations are always nice to have, they tend to help me understand the world better

I too am interested in seeing the next Gen STi. I doubt I’ll dump my CTR for one, but it sounds like they’ll actually be creating an all new car. If so, I’m really curious to see what they come up with.

CivilciviC said:

I too am interested in seeing the next Gen STi. I doubt I’ll dump my CTR for one, but it sounds like they’ll actually be creating an all new car. If so, I’m really curious to see what they come up with.

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Same, personally hoping it has the 350-375 HP to keep it competitive with the current generation (basically Focus RS or slightly better). There was also the rumor of the 400-ish (slightly less) HP AWD Golf as well, though I think that's hit the graveyard by now (for a second time).