Indium Gray Metallic Money Pit Mk7.5R

[scrllock]

Beautiful weekend at Grattan, the car was massively improved with seats and harnesses. Had a 1:31 on the potenza sports, which become useless after a couple laps. Not ideal, but my fault for not trying to see if an extra wheelset still fit in the car until 10pm the night before. Ran the 25psi map from Kalam through 8 sessions, no engine issues. Half-ass Mk8 pcv retrofit did well.

No hood problems, thanks to this cheap solution:

Zach, the owner of Zestek, brought out his supercharged e92 "daily" m3, with a completely gutted interior, single tillet seat, and full aero. Has a full CF wheel on his adapter, which I think I'll need to snag.

Speaking of CF, the R is definitely going on a diet. Despite the seat removal and other minor weight reduction, it's still pretty heavy:

That's half a tank of fuel with the AGM battery in, so a bit below 3300 dry with the LiFePo4 battery. I think I can get 70-80lbs out (which is certainly noticeable), but it will be pricey/annoying after that (speakers/door cards, subframes, wipers, forged wheels, CF trunk/fenders, etc.)


Weight distribution is also poor, but I will probably go to stiffer springs before messing with corner-balancing. Looking at options for that now.

 

[manu97]

View attachment 305685

Beautiful weekend at Grattan, the car was massively improved with seats and harnesses. Had a 1:31 on the potenza sports, which become useless after a couple laps. Not ideal, but my fault for not trying to see if an extra wheelset still fit in the car until 10pm the night before. Ran the 25psi map from Kalam through 8 sessions, no engine issues. Half-ass Mk8 pcv retrofit did well.

No hood problems, thanks to this cheap solution:

View attachment 305686

Zach, the owner of Zestek, brought out his supercharged e92 "daily" m3, with a completely gutted interior, single tillet seat, and full aero. Has a full CF wheel on his adapter, which I think I'll need to snag.


View attachment 305688


Speaking of CF, the R is definitely going on a diet. Despite the seat removal and other minor weight reduction, it's still pretty heavy:

View attachment 305689

That's half a tank of fuel with the AGM battery in, so a bit below 3300 dry with the LiFePo4 battery. I think I can get 70-80lbs out (which is certainly noticeable), but it will be pricey/annoying after that (speakers/door cards, subframes, wipers, forged wheels, CF trunk/fenders, etc.)


Weight distribution is also poor, but I will probably go to stiffer springs before messing with corner-balancing. Looking at options for that now.

What all weight reduction have you done? And what's on the list?

 

[scrllock]

What all weight reduction have you done? And what's on the list?

Removed: rear seats, subwoofer, mats, tools, plastic trim around rollbar, windshield fluid reservoir.
Lightened: wheels, front calipers, hood, front seats, battery, suspension (aluminum coilovers + toe arms).
Added weight from rollbar and harnesses.


Easiest loss is a titanium catback, either from a cheap fabricator or have my Chinese guys source an alibaba special for me. Easy 40+ lbs since the AWE is even heavier than stock. Valves are nice but not necessary.
CF trunk is about $100/lb. Forged wheels are a bit more than that, but rotating mass is much more important. Going back to a 2pc rear rotor is also around $100/lb. 370mm girodiscs were around $183/lb, but not just for weight. Verkline front subframe is about $188/lb. Rear is >$200/lb. Stuff like aluminum arms would be even worse.

Small things like door cards will be very minor, mostly just covering up the lack of speakers. Getting another 100+ lbs out of it would probably require lexan windows and/or lightened doors, which would make the car extremely uncompetitive and/or require a fullly welded cage, so I think I'm going to have to settle for being in the 3200s with fuel and no driver.

 

[manu97]

Removed: rear seats, subwoofer, mats, tools, plastic trim around rollbar, windshield fluid reservoir.
Lightened: wheels, front calipers, hood, front seats, battery, suspension (aluminum coilovers + toe arms).
Added weight from rollbar and harnesses.


Easiest loss is a titanium catback, either from a cheap fabricator or have my Chinese guys source an alibaba special for me. Easy 40+ lbs since the AWE is even heavier than stock. Valves are nice but not necessary.
CF trunk is about $100/lb. Forged wheels are a bit more than that, but rotating mass is much more important. Going back to a 2pc rear rotor is also around $100/lb. 370mm girodiscs were around $183/lb, but not just for weight.

Small things like door cards will be very minor, mostly just covering up the lack of speakers. Getting another 100+ lbs out of it would probably require lexan windows and/or lightened doors, which would make the car extremely uncompetitive and/or require a fullly welded cage, so I think I'm going to have to settle for being in the 3200s with fuel and no driver.

Definitely a stupid question - open downpipe or downpipe turndown? Or way too loud? Unsure if you're still street driving this at all.

 

[scrllock]

Definitely a stupid question - open downpipe or downpipe turndown? Or way too loud? Unsure if you're still street driving this at all.

I have a 400cpsi GESI cat behind the subframe, then it goes through a big vibrant resonator by the rear diff, splitting off into a tiny muffler and a valved section before the tips. One of the local tracks has a strict sound limit, and my neighbors across the street work in the morning and have a bunch of kids in school. I had it completely straight-piped for about a month in 2022 and it will always have a muffler. I don't plan on deleting the cat again unless it gets a bigger turbo, which won't happen until the motor gets some beefier rods.

 

[scrllock]

Got some cool shots at T3 and the jump. Hoped for some T12 drift photos in the rain, oh well.

Still has a good amount of time in it without more power and aero, looking at options for timed events next year.

The annoying part of building to a class is that the options are either spend another 20k (power, aero, fancier suspension) or give up a bunch of the cool OEM+ stuff. On the other hand, most of that isn't doing a whole lot to make the car faster, so we can set a baseline to decide if it's worth ripping a bunch of stuff off.

 

[MonkeyMD]

View attachment 305849

Got some cool shots at T3 and the jump. Hoped for some T12 drift photos in the rain, oh well.

Still has a good amount of time in it without more power and aero, looking at options for timed events next year.

The annoying part of building to a class is that the options are either spend another 20k (power, aero, fancier suspension) or give up a bunch of the cool OEM+ stuff. On the other hand, most of that isn't doing a whole lot to make the car faster, so we can set a baseline to decide if it's worth ripping a bunch of stuff off.

I know guys like a gap, but that's next level

And is your hood open?

 

[golfRdaddy]

I know guys like a gap, but that's next level

And is your hood open?

Think that's tape and thats a pic when he hit a jump?

 

[scrllock]

I know guys like a gap, but that's next level

And is your hood open?

Full droop coming off the jump. I usually let off before the crest.

The PDC hood is awful. See the photo where it's half-covered in gaffer tape.

 

[messrock]

Full droop coming off the jump. I usually let off before the crest.

The PDC hood is awful. See the photo where it's half-covered in gaffer tape.

The P is for poor.

 

[scrllock]

Went to get some logs last night, map 5 acted funky, kinda like it had a partial boost leak. Only made about half of the boost it normally does.

Back into other maps and it was the same way. Tore it apart last night, no loose piping and no play in the compressor. Put it back and it's got a misfire, mostly on cyl1.

Not sure what's up with it, WGDC% isn't very high during the last pull I did, which you'd think it'd jump up with a leak; that's what happened when the last turbo died.

Gotta tear into it more later, do the obvious misfire diagnosis work.

 

[scrllock]

Wellp, RIP DLRA #2.

Cylinder 2 wall:

All of them are like this, 2 is probably the most dramatic.

Bits of wall/ring on #4:

Not sure if the block is reusable or not. Cores are expensive, as are new OEM rings/pistons. Unsure whether it makes more sense to go for a built block with 2618 pistons or go back to a stock setup with even more conservative tune.

 

[manu97]

Wellp, RIP DLRA #2.

Cylinder 2 wall:

View attachment 305894

All of them are like this, 2 is probably the most dramatic.

Bits of wall/ring on #4:

View attachment 305895

Not sure if the block is reusable or not. Cores are expensive, as are new OEM rings/pistons. Unsure whether it makes more sense to go for a built block with 2618 pistons or go back to a stock setup with even more conservative tune.

damn man. feels like if you're going built block, you'd want bigger turbo = more heat = more problems on track? or you'd need more cooling. feels like that gets very expensive very quickly

 

[El_bigote_AJ]

On brand, but still Ouch…

 

[ChrisMk77]

Sucks, did you log that session at all?