HPDE, 135i vs boosted BRZ/FRS

[imported_mega]

Getting bored with my R53 mini, thinking about what is next. I've owned a 135i before and I currently own a 07 335i sedan. I also own a toyota 86, this car is very fun like the mini, with similar power and can fit lots of tire in HPDE Trim. if I get another 135i it would probably be a automatic as they are much cheaper here unless I can find a good deal on a 6MT, I do enjoy heel toe driving

Car would be partially stripped, basically an autocross SM build, lots of tire, aero, rear interior stripped and basic power mods. IF I build a brz it would be similar with a supercharger, it's unfair how they can go from 215 tires to 265 without much work, and are very light.

Anyone drove both?

little vid from last year at VIR

[The Wind Breezes]

If you want an auto get the DCT. It is better than a manual for driving events. The N54's auto sucks ass for performance driving.

The 1 sucks without a good diff ($$$$) alternatively you can weld the diff. If you have to run stock diff forget about this car. Don't even bother.

You have to code out a bunch of shit (see thread on removing electronic nannies) to get the car to behave normally while driving hard even with DSC OFF.

Camber plates are a minimum to get the car balanced fun. Stock balance has way too much rear neg camber for stability. And of course you'll want all kinds of bushings and odds and ends to replace the ones on the car cuz they outright suck for hard driving.

I run a square 225 setup on stock wheels which works very well for "fun" street driving. But of course a car this heavy wants a lot more front tire on the track, which means you probably need to modify / replace the front fenders even with added front neg camber.

The car has way too much safety and high speed engineering to be a good platform for what you want unless you intend to really get bare bones (which I fully support). That would be really cool.

Unfortunately, the more weight you take out the more unbalanced the car becomes since most low hanging fruit to be removed weight wise is in the rear.

Finally, if you are in a hot climate with DCT you may overheat the car stock on track if you really drive hard.

[imported_mega]

I've not had any issues with our automatic, it goes what I ask of it, I would code out the stupid kickdown switch though

[Mark Aubele]

You can fit 255s on 17x9s under stock fenders with the proper offset. Although it really isn't enough tire we are finding even with a tune on the stock turbo. We haven't had any issues with the DCT at all, although we don't usually run more than 2-3 hard laps at a time.

BRZ is certainly a good chassis, but fuck trusting a boosted one on track.

Budget for a diff, it is absolutely necessary. We have a MFactory helical, car came with it, would've gone clutch type, but it works well. Don't even consider welding the diff unless you only plan to drift it.

[beattiecj]

Originally Posted by Mark Aubele

You can fit 255s on 17x9s under stock fenders with the proper offset. Although it really isn't enough tire we are finding even with a tune on the stock turbo. We haven't had any issues with the DCT at all, although we don't usually run more than 2-3 hard laps at a time.

BRZ is certainly a good chassis, but fuck trusting a boosted one on track.

Agree avoid a boosted BRZ... A well track prepped BRZ is just as fast or faster than a 135i with mild upgrades e.g. suspension, pads and 200tw tires and stock power.

I've had no issues with a DCT overheating, and an Oil cooler or two resolves the high oil temp issues on the 135i.

If you are trying to race, prob long term BRZ is better platform.
I am dying to drive one to see the comparison between the two, either way I think you can have fun in either.

[imported_mega]

not interested in racing, I'm happy instructing

there's tons of boosted brz hpde'ng and a few serious TT cars, oil cooling is critical much like the n54

[The Wind Breezes]

Originally Posted by Mark Aubele

Don't even consider welding the diff unless you only plan to drift it.

And your frame of reference is? My car has had a welded diff for 3 years. It works great for HPDE unless you're on a gokart track. I don't even drift, I just drive hard and this thing is perfect for the task. Of course you need to adapt your driving style.

[NinjaDog]

Originally Posted by The Wind Breezes

And your frame of reference is? My car has had a welded diff for 3 years. It works great for HPDE unless you're on a gokart track. I don't even drift, I just drive hard and this thing is perfect for the task. Of course you need to adapt your driving style.

Are you running a diff bracket as well as the welded diff? If so, what's the difference?

Keen to try this out before spending the money on an LSD

[Bodie217]

Originally Posted by imported_mega

not interested in racing, I'm happy instructing

there's tons of boosted brz hpde'ng and a few serious TT cars, oil cooling is critical much like the n54

If you are just instructing, I think the BRZ/FRS is the right car. Don't even need to boost it. At my last HPDE, there was a N/A BRZ running away from my instructor's 2018 M3 in the corners.

[Relegate]

Both cars will require an investment to bring the potential out. The BRZ has something the 135i will never have: light weight. You can run 255/40/17 on both but one is 600lbs lighter than the other out of the box. I have. A friend with a BRZ that is supercharged and puts down 235whp. He absolutely flies and I’m generally the fastest street 135i our there at my track days and I can’t get within 2-3 seconds a lap of him on stock tune or MHD2+. I do not have an LSD but will pull the trigger soon.

It depends what you want and which community you want to be a part of imho. The BRZ’s are low cg, light and reasonably reliable with used parts sourced much cheaper than the 1’s.

FWIW- I ran yesterday stock power and then MHD stage 2+ and the lap time difference was 1/2 a second. I run 255/40/17 re71’s Square with -2.5 camber which will get to -3.2 once I swap camber plates. That will help a bit. Tons of other upgrades, splitter, vented hood, aero motions wing, n55 dct with ST XTA coil overs on 9k/12k springs. There were 2 other 135’s (one an IS and the other an N54) and I was 10 seconds a lap faster than them FWIW.

[bbnks2]

BRZ/FRS will be hands-down the better car in the short-term and minimal mods.

Once you heavily mod both cars over the long-term it balances out. The 135i is a luxury car in stock form. It has tons of potential but it won't perform anywhere near as well on the track as the 86 does out of the box. But again, a serious track car will move to aftermarket suspension, bushings, differential, fender flares, cooling, tires, etc. so all the 135i's "weak" points people are mentioning are pretty moot. The 135i has the power-weight advantage even after boosting the 86... Not to mention things like the axles, drive line, diff, etc. are all much beefier to handle the power whereas the 86 power-train is made of glass.

Also, take a look at Pirelli world challenge results. M235iR is homolugated to run at 280 hp (de-tuned) and still turns faster lap times than race prepped 86's. Lots of people out there don't really understand how much potential these cars have in the right hands. I look forward to when they become the new HPDE E36 lol. Cheap fun for the avg HPDE enthusiast. You won't need to finance one either like you probably will the FRS/BRZ lol

The weight difference is also not as significant as people claim... Race seats(-67lbs), lightweight battery(-30lb), aftermarket muffler(-15lb), downpipe (-15lb), wheels/tires(-40lbs), and your 135i will be <3200lbs. Probably close to being <3,100lb with those modest things done. An FRS weighs 2800lbs and already comes with featherlight equipment so there is little gains to be had like on the 135i.

350-400whp (modest tune) in a 3200lb 135i is going to be faster than a 2750lb (plus add the weight of supercharging it +50-100lbs) FRS with 240whp (supercharged)... if you know how to set a car up right that is...

[Relegate]

I don’t think an N55 is going to be making 350-400whp on stock turbo without other mods, but you can make them competitive with one another and from what you are saying it’s really the same parts for both. (Coilovers, Control Arms, swap bars, etc). On a track I know well, I’m 3 seconds faster than my buddy in the BRZ. We are both 12:1 power to weight. I love the grunt of the 135, although the lack of top end power is frustrating. Either way: driver mod is always the best mod.

My 135 is stock interior, no back seat base, 17” wheels, etc and is 3340 on the corner balance scales. I hope to get another chunk out with what you’ve recommended above (seats, etc). I am catted DP and no muffler, etc. sunroof weighs 35lbs fwiw. The one always draws a crowd and although I was faster than both camaros (14 SS and 19SS 1LE, on re71 and 888R respectively) it was purely driver.

My friend with the BRZ (winner of the 86 Cup) did lose his trans a couple weeks ago.

[Captain Blood]

I don't know much about the BRZ, except they are tiny like a Miata.

I have a family friend who ran a N54 135 track car (not street legal) and when he saw that I had bought a 135 got very excited and asked me lots of questions about what I was going to do with it. He related to me that he was now tracking a Miata as his 135 had become too expensive to maintain, but he frequently wished he had stuck with that over the Miata.

[Relegate]

I had a NA Miata track car. Was almost free to run. Was too slow for what I was used to. Once I’d hit traffic everyone would be on my butt for point by’s. Sold it to put a new trans in my 996 track car which then promptly blew the motor... that’s when I got the 135i. Miata was great for getting my friend into track driving!

[Mark Aubele]

Originally Posted by The Wind Breezes

And your frame of reference is? My car has had a welded diff for 3 years. It works great for HPDE unless you're on a gokart track. I don't even drift, I just drive hard and this thing is perfect for the task. Of course you need to adapt your driving style.

I don't think I even have to argue why a welded diff sucks for anything dude. If it works for you, go for it. There is a reason why in 21 years of doing this shit you are the first person I know of besides the occasional dirt track guy that shows up to a hillclimb that runs a welded diff for anything outside of drag racing or drifting.

[Mark Aubele]

Originally Posted by Relegate

I don’t think an N55 is going to be making 350-400whp on stock turbo without other mods

We made 357/449 on E30 with only a downpipe. That was with stock IC, have since gone to E50 and aftermarket IC, haven't been back to the dyno yet. It's almost diesel like though, power falls off hard above 5200. Definitely not enough turbo but she runs in BSP for now, so can't change it.

[imported_mega]

Originally Posted by Relegate

On a track I know well, I’m 3 seconds faster than my buddy in the BRZ. We are both 12:1 power to weight. I love the grunt of the 135, although the lack of top end power is frustrating. Either way: driver mod is always the best mod.

what mods does your friend have?

I think the build costs for both cars is similar in the end, and i have found both cars at similar price points, looking at salvage title cars.

[Ginger_Extract]

Unsure about your local tracks, but out here, an NA 86 with just bolt-ons, E85 tune, suspension, wheels/tires will embarrass a 135i, until you have a widebody, all the cooling on earth and enough reliability to do a more than 2 laps at full power.

Having driven both on track, extensively, it's no contest, the 86 is just a better track car. It's much lighter, handles better out of the box than even a modified 135i, and is a much less expensive car to run.

[imported_mega]

Vir is my local track, getting passed by cars nearly double my speed does get old, thankfully the advanced and instructor groups know how to deal with momentum cars like my mini

[Relegate]

Originally Posted by imported_mega

what mods does your friend have?

I think the build costs for both cars is similar in the end, and i have found both cars at similar price points, looking at salvage title cars.

I don’t know everything, he’s @strife_7_101 on IG. He has supercharger, injectors, stock exhaust per class rules, Ohlins R&T, some aero (splitter, hood vents and wing), 17x9 wheels, pads and fluid. I actually don’t know if he has upgraded brakes. I’d imagine he has bushings all done, the car is prepped by Dunn Fab in NJ who is making some pretty awesome BRZ’s around here embarrassing a lot of cars at NJMP.

I don’t agree with Ginger_Extract about a stock brz with tires, e85 “embarrassing” a mildly setup 135i - but - I do agree with the rest of his notions 100%. I’ve never been passed by stock-ish power BRZ in my 135.... not saying a race driver couldn’t but that’s a little different story. I “battled” with a local guy (who thinks he’s hot dookie on track) in his NA BRZ track car a couple weeks ago. I’m FBO with stock tune that day and was running 3-5 seconds a lap faster my second time at NJMP Lightning. BRZ was no doubt better in some of the corners. I do have some “aero” but cheap coil overs and aggressive street alignment. He was on R888R’s to my RE71’s so there no real difference there. But, the BRZ capable AF. The one thing the will always effect the 135 is the weight.

I’ve only ever been passed by one other e82/92 like ours and it was a 1M Track Car on big ass slicks, MCS 3-way, full track suspension, Cage, seats, etc.

[Relegate]

Originally Posted by Mark Aubele

We made 357/449 on E30 with only a downpipe. That was with stock IC, have since gone to E50 and aftermarket IC, haven't been back to the dyno yet. It's almost diesel like though, power falls off hard above 5200. Definitely not enough turbo but she runs in BSP for now, so can't change it.

That’s solid power, I’ve seen that from some shops I work with. I have no e85 anywhere near me. How is it on a road course? My car drops off a cliff at 5800 which means I’m always a gear higher instead of winding out the correct gear. Would love a bigger compressor wheel to pull to 6700 or so.

[Mark Aubele]

Originally Posted by Relegate

That’s solid power, I’ve seen that from some shops I work with. I have no e85 anywhere near me. How is it on a road course? My car drops off a cliff at 5800 which means I’m always a gear higher instead of winding out the correct gear. Would love a bigger compressor wheel to pull to 6700 or so.

It's my wife's track car so I only have autocross and street time with it, but honestly I don't really like it. It has a massive midrange, but like you said it falls off hard up top. Took it to the dragstrip to see where she should be shifting it, letting the car shift itself at ~7000 it trapped 109mph, shifting it at 5800 it trapped 112.

It certainly works but it was really hard to modulate at low speeds. She doesn't have any issues at the faster hillclimbs we run but this past weekend was having some difficulty getting out of slower corners. I have an easier time getting power down in my 504 rwhp 2525lb E36.

All the hills we run are out your way, a couple of friends we race with run E85 can't remember where they get it. I know they have to drive like 45 min away. We have it everywhere around here.