So you want a 400+ RWHP 818 huh?

[Wayne Presley]

Here is what they are like...
Annihilates the tires in first and second

https://www.youtube.com/watch?v=cC3cSykGIIQ

[Wayne Presley]

Spins the tires in third

https://www.youtube.com/watch?v=C3CZKoLbwg4

[Wayne Presley]

And accelerates like the hand of god is pushing you in 4th


https://www.youtube.com/watch?v=eW78mA34SHo

[Frank818]

You need better gearing. :)
I'm heading there anyway, my engine has 400. Oh well, I'll see how to gear it up to minimize spin.

What tires you have?

[JeromeS13]

I'd like to see those data logs. :-D

[Hindsight]

Needs an LSD and Race Logic traction control. :) Or does it already have an LSD? If so.... WOW!

[Wayne Presley]

You need better gearing. :)
I'm heading there anyway, my engine has 400. Oh well, I'll see how to gear it up to minimize spin.

What tires you have?
Yokohama Avan Neova AD08


I'd like to see those data logs. :-D
I'll download the dash tomorrow


Needs an LSD and Race Logic traction control. :) Or does it already have an LSD? If so.... WOW!
It has a LSD...

[Aero STI]

Looks like a blast Wayne! Based on the hood color I'm assuming this isn't the H6, what are the engine/turbo specs?

I can't wait to drive my car after the winter mods are done. It was fun at 230 WHP. I'm adding 2.5i intake, twin scroll manifold, EFR7163, and E85 to name a few. It should be good for high 400's or low 500's at the rear wheels.

[STiPWRD]

How wide were the rear tires and what was the rough temperature outside???

[Wayne Presley]

Looks like a blast Wayne! Based on the hood color I'm assuming this isn't the H6, what are the engine/turbo specs?

I can't wait to drive my car after the winter mods are done. It was fun at 230 WHP. I'm adding 2.5i intake, twin scroll manifold, EFR7163, and E85 to name a few. It should be good for high 400's or low 500's at the rear wheels.

It has STI block and crank, forged rods and pistons, Blouch 2.5 XTR turbo, 1000cc injectors, Electromotive TEC-S, VCP AWIC, Perrin equal length headers/up pipe, VCP custom exhaust, Tial 40mm WG.

[Jeff Kleiner]

It has STI block and crank, forged rods and pistons, Blouch 2.5 XTR turbo, 1000cc injectors, Electromotive TEC-S, VCP AWIC, Perrin equal length headers/up pipe, VCP custom exhaust, Tial 40mm WG.

And clearly not enough traction to put it to the ground ;)

Jeff

[Kurk818]

Running a very similar setup to Wayne, I can definitely agree to the "Hand of God" comment. It puts quite the grin on ones face :o

295's in the rear dont help much for the spin either. Running Hankook V12s

Im at 380hp/380tq on 91octane at 21psi.

[metalmaker12]

I will be at around 330-375 18-21 psi wheel soon, very similar setup except 1.5 dom twinscroll. I spun the tires with like 250whp in three gears before. Buts it not like your not moving forward without authority, your moving forward very fast and spinning em. Traction control is in your right foot, it would help, but might make the car less fun. The car is just plan fast in every way.

[Frank818]

Yokohama Avan Neova AD08

Oh crap, same as mines, they are awesome. :D Then 400hp is frickin awesome! loll

Longer 1-2-3 gears would help a bit, but would not stop the spinning.

[Wayne Presley]

I'd like to see those data logs. :-D

Here they are

http://i213.photobucket.com/albums/cc175/vcpinjectionpb/datalog818_zpsdbd4f936.jpg (http://s213.photobucket.com/user/vcpinjectionpb/media/datalog818_zpsdbd4f936.jpg.html)

[Hindsight]

Wayne, have you done a dom 1.5 yet? Seems like you've done at least two or more 2.5s? Obviously the 2.5 will make more power but it sure does seem to come on like a dump truck rear-ending you at 100mph. I wonder if the 1.5 wouldn't have a more... gentle onset of torque? Curious to hear your observations if you've done one. Honestly the 2.5 seems down right scary to me from those vids. I don't think I'd trust myself with it without an electronic traction control system and even then.....

Thanks for posting the data! Great to see that AWIC is doing it's job. Looking forward to ordering mine when I get to that point.

[EODTech87]

That 4th gear pull appears to be roughly 90-110 mph. Do you have a time for how long it took?

[AZPete]

To answer Wayne's question: No way!
My 818S with stock turbo 2.5 will be plenty fast and stay on the road, hopefully.

[Buzz Skyline]

To answer Wayne's question: No way!
My 818S with stock turbo 2.5 will be plenty fast and stay on the road, hopefully.

I'm with you. I've driven my stock 2.0 in gocart mode quite a bit, and it's darned entertaining as is.

[nkw8181]

With that I think I'll be good I may still spring for a used sti turbo before tuning.

[ssssly]

How wide were the rear tires and what was the rough temperature outside???

^^^ That?

[Wayne Presley]

That 4th gear pull appears to be roughly 90-110 mph. Do you have a time for how long it took?

The 3-4 run from 49 to 116 mph took 6.2 seconds
the 4th gear portion from 85 to 116 mph took 2.8 seconds

[Wayne Presley]

How wide were the rear tires and what was the rough temperature outside???

rear tires are 255 and it was a chilly 75°F outside:cool:

[ssssly]

Thanks.

Looks like I should start getting ready for how to get 305s on mine.

That or super conservative WG duty tables.

Maybe a bit of both.

[Frank818]

The 3-4 run from 49 to 116 mph took 6.2 seconds
the 4th gear portion from 85 to 116 mph took 2.8 seconds

Pardon my very slight sarcastic disappointment, it's a bit slower than I expected for 4th gear. I thought 20km/h per second could be achievable, which is my secret goal, but this is "only" 17.3km/h. On the other hand, it means it's quite possible to get 20. Tires (I have a little wider), gear ratio (will find the best), power delivery, etc., I just need to play with that and I should make it. Everyone's got to have a goal, this one is one of mine, but hush. :)

Tnx for the numbers Wayne, it paves the way to a lot of comparisons! :) I like it.

[johngeorge]

Wayne, SWEET!! Ohh and where is the G plot? how many G's under acceleration?

[D Clary]

Is there any way to reconfigure the trailing arms for more traction? Maybe more angle? I realize that anything you do to create more forward traction will reduce traction under braking, but with the bulk of the weight in the rear perhaps we could fudge a little on the trailing arm angle.

[K3LAG]

I am even more convinced I don't want 400+ HP. Not even 300+ really. I'll be happy in mid 200's. :)

That's nothing against all you guys that do, I'm just not THAT nuts! ;)

Larry

[Flamshackle]

I wonder what traction control on this would look like? I would be afraid to drive this kind of power without it...

[svanlare]

Thanks Wayne for the post and data. I've been debating traction control or not. This certainly makes a case that my stock engine will be highly entertaining as is and traction control might be worth the cost and effort.

[Jaime]

I thought 20km/h per second could be achievable, which is my secret goal, but this is "only" 17.3km/h. On the other hand, it means it's quite possible to get 20.
The theoretical max acceleration for a 2000 pound vehicle with 400HP at the wheels is 26.4km/hr per second at 100mph, ignoring air resistance. If you lose less than 97HP to drag and hook up, you'll hit your 20.

If a 400hp 818 could hit a 160 mph top speed - drag limited, then it should only see 60HP of drag at 100mph. 160 sounds reasonable to me, so I'm going with it. That would leave 340HP for forward motivation at 100mph, giving acceleration of 22.5km/h per second. That's 0.63g's (feels like 7.4 at the tires if you add in drag). You would need enough traction to run a 3.5 second 0 to 60. Could be challenging.

[Frank818]

The theoretical max acceleration for a 2000 pound vehicle with 400HP at the wheels is 26.4km/hr per second at 100mph, ignoring air resistance. If you lose less than 97HP to drag and hook up, you'll hit your 20.

If a 400hp 818 could hit a 160 mph top speed - drag limited, then it should only see 60HP of drag at 100mph. 160 sounds reasonable to me, so I'm going with it. That would leave 340HP for forward motivation at 100mph, giving acceleration of 22.5km/h per second. That's 0.63g's (feels like 7.4 at the tires if you add in drag). You would need enough traction to run a 3.5 second 0 to 60. Could be challenging.

Good ol' engineer calculations, I like that! :)
I take the challenge. Not saying I'll make it, since I may well be over 2000lbs (might hit 2200 :(((().

My top gear should hit about 180mph according to my excel sheet. And that sheet has proven to be within 2-3mph accurate at 80mph with my Corrado. I guess 6-7mph accurate at 160, then.

[Bob_n_Cincy]

My top gear should hit about 180mph according to my excel sheet. And that sheet has proven to be within 2-3mph accurate at 80mph with my Corrado. I guess 6-7mph accurate at 160, then.

Hi Frank
What did you use for aerodynamic drag coefficient for the 818? I wish FFR would publish this for the different aero configurations. Having this number will be critical on my electric version making decision between down force and range.

Great video and info Wayne.
Bob

[Frank818]

Hey Bob,

My answer may surprise you: none.
My excel sheet seemed pretty much close with the Corrado (0.32cx I think) and I assumed the same could apply on the 818. Assumed!
I do take tire diameter into account.

With my Corrado sheet, I checked at 6500rpm top gear what would be the speed on OEM tires and I compared with the actual speed testers and VW are saying the car does (141mph). My simple sheet was 1-2km/h off from that speed. By deduction, I assumed my sheet was ok, cuz with same rpm as the one it's been tested at I get the same speed. Plus when I actually tested it myself I was barely off a few at 80mph. I used GPS and I was not at 6500 top gear, of course. But the rpm on my sheet matched very close the actual car's rpm on the road. At that speed, which is far from 140mph.

And I stupidly assumed the same could apply with the 818.
If my sheet says 180, I have fate I would hit over 160.

And who knows, maybe I had back winds when I tested it, or front winds or side, or maybe I was not on a perfect leveled road. Too many things to check, cuz it was not scientific, so I kept it simple and I wasn't that much off. Luck? I don't know.

[Scargo]

If I'm at 25.4 max OD on the wheels and can turn 9K (let's just say 8K) with a 250 or 400 whp engine (ST-2 or ST-1) and a close-ratio six-speed box, how fast can I go in an R that weights 2,000 pounds with me in it? Pretty frik'n fast, right?

[Hindsight]

Isnt 400hp over the power to weight cap for ST1?

[Scargo]

No. 5:1

[Hindsight]

Wow, that would make for quite a ride

[R.Spec]

In other news. How can we maximize traction? what tires and what width can we squeeze?

[metalmaker12]

Thanks.

Looks like I should start getting ready for how to get 305s on mine.

That or super conservative WG duty tables.

Maybe a bit of both.

I think you could reduce peak boost onset with wgdc if you so desired to control traction, say setup with duty cycles to just be under the chosen turbos efficiency range from say 3,000-3,800-4,200 , but be slightly building between these rpms from like (15-19psi) on my dom 1.5) it would be a lot if trial and error.

[Hindsight]

In other news. How can we maximize traction? what tires and what width can we squeeze?

Sticky tires, limited slip differential, and an electronic traction control system. Max width tire is 255 with the stock body. Wheel size won't matter so long as it's appropriate for a 255 tire (generally that means 8 or 8.5 to 9.5 or so). Bigger tires will require fender flares.

[Scargo]

I might beg to differ. Caveat: I have done custom trailing arms and am using a six-speed and STi uprights. Don't have the axles in yet, but that shouldn't matter. I can get custom length axles made.
This shows my 275 Goodrich R1's (same as Hoosier 285's) on 10.5" rims with a 38ET and 10mm spacing. It is very tight inside, but looks like I can make it work with a little juggling. Actual wheels may be only 10" and 30 ET. Nothing has been fudged or trimmed on the fiberglass. Looks to me like it might work...
https://scontent-a-atl.xx.fbcdn.net/hphotos-xap1/v/t1.0-9/10801897_1007309415952837_1519372866452917866_n.jp g?oh=0e7ad7fe1a5a62ef59b0aa6c467a8f5b&oe=55130523https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-xfp1/v/t1.0-9/10371938_1007309412619504_534425720664875718_n.jpg ?oh=c452f104ff083833f7da0bcf15de1644&oe=55081722&__gda__=1426557611_4c7f08b521cd87388c38f6c1d12c4a3 4

[Plebeian]

Great vid, thanks for posting. Interesting how a Roadster doesn't have those traction issues if set up at a similiar power to weight ratio (using mine for comparison). I assume the difference is due to gearing and tires. Cheers.

[Wayne Presley]

Great vid, thanks for posting. Interesting how a Roadster doesn't have those traction issues if set up at a similiar power to weight ratio (using mine for comparison). I assume the difference is due to gearing and tires. Cheers.

Or the sudden onset of 250 RWHP gain over 2000 RPM...

[longislandwrx]

Or the sudden onset of 250 RWHP gain over 2000 RPM...

I need tire temp specs in 8+ places, wear indicator capitulator readings, vtec set point diagnostics, mr. fusion gigawatt readings and ibu bitterness scale numbers.

JK cool vid must be a hoot to drive.

[Scargo]

You forgot tire F&M data.