Rennlist Editor

had to share that GT4 Clubsport vid with the front page...
https://rennlist.com/articles/jelly-...gt4-clubsport/

GT4VR

Rabble rabble rabble. Who took the jam outta your doughnut?

I did not claim in any way to know anything. I obviously wouldn't ask a question if I knew the answer. I also did not personally recommend anyone should take their car straight from the dealer to the track. All I'm saying is: does anyone have any actual statistically relevant data (not looking for anecdotal evidence) on what exactly are the issues, when do they occur, and to what degree for various break-in procedures?

From Wikipedia (and please spare me the rant on its validity):

The other reason for shorter break-in regimens today is that a greater amount of science has been applied to the understanding of break-in, and this has led to the realization that some of the old, long, painstaking break-in regimens were based on specious reasoning. People developed elaborate theories on what was needed and why, and it was hard to sift the empirical evidence in trying to test or confirm the theories. Anecdotal evidence and confirmation bias definitely played at least some part. Today engineers can confidently advise users not to put too much stock in old theories of long, elaborate break-in regimens. Some users will not give credence to the engineers and will stick to their own ideas anyway; but their careful break-in beliefs are still harmless and serve roughly like a placebo in allowing them to assure themselves that they've maximized the equipment's working lifespan through their due diligence.

https://en.wikipedia.org/wiki/Break-...hanical_run-in)

GT4VR

Love that picture!





Will start a new thread on break-in if my question is too OT.

vantage

Break-in is something that people have debated on Rennlist (and other forums) for as long as internet forums have existed! I'm sure you would find dozens of threads on it.

O5C4R

[QUOTE=GT4VR;13029485
I had an Ariel Atom and their recommendation (in the manual!) was to drive it like I stole it from the beginning, that somehow that set the pistons the best for longevity and power - but they also conceded that different people have different philosophies. Just curious if there are studies done on modern engines or if it's all old wives' tales.

(yes, just called y'all a bunch of old wives)[/QUOTE]

that's what I was advised for my 1M and my 991 C2S in straya

Alan Smithee

Did I see a BAC Mono in the background? Any video of it?

d00d

Here's the thermal based break in logic, as explained by a Porsche Engineer;
http://yel.pca.org/porsche-engine-break-in/

GrantG

Interesting that the peak performance comes at 20,000 miles if you follow break-in procedure. Maybe peak performance comes sooner (and maybe declines sooner) without break-in? Maybe this is why race motors receive no break-in?

GT4VR

Thanks for posting that article. Although they don't actually give any specifics around the real effect of different break-in procedures or point to any research. Obviously the Porsche guys know engines and mechanics and are no dummies, but there are still no specifics around the effects of different break in periods.

All they're really saying is "if you wait until 2,000 miles to go above 4,000 rpm we know the engines will last a long time", but anyone that has studied logic games for the LSAT knows that that doesn't necessarily mean that if you don't wait until 2,000 miles the engine won't last a long time. Just because you know X works well, doesn't mean that Y and Z don't work well too.

And what's a long engine life? Does a 2,000 mile break in give you a 300,000 mile engine while a 200 mile break in period give you 200,000? Or does your horsepower drop 10% after 100,000 miles with a 200 mile break-in vs 5% after 100k miles with a 2,000 mile break-in?

I'll search the forum more in detail now, although I suspect from my Google searches that there really isn't much data on this. It's not because the auto industry is lazy or not scientific either of course. I believe it's because technology is moving so quickly with cars that what was a valid study 10 years ago no longer holds true today. So they would have to run tests all the time and because there isn't much money involved in exactly this and apparently for race cars where engines get rebuilt all the time it's not that important and because it's easy to give a conservative answer that will cover their asses, there isn't enough incentive for anyone to carry out a proper test.

Quikag

I just think there are too many variables on break-in to be able to tell definitively. Engine/drivetrain warmup, driving cycles, frequency of driving, oil change intervals, manufacturing tolerances. I would imagine Porsche (as most manufacturers do) engineer for the lowest common denominator and figure the worst on break-in.

Think about it. How many people who lease Porsches (and a BUNCH of them are leased) follow a 2,000 break-in? Maybe 5%. That PDK in sport plus mode gets up to high rpm VERY quickly even under light to moderate throttle.

How many new Porsches have you heard with blown engines and blown diffs? Not too many.

I waited about 600 miles before redline and I'm pretty sure my engine isn't going to blow up anytime soon. It's all about a proper warm-up each time you drive before flogging IMHO.

Quikag

I remember reading an article a while back where GM or maybe it was Ford (and I'm sure almost every manufacturer) does some pretty brutal durability and reliability testing. They would freeze a car overnight in a specially designed ice chamber and start it up in the morning and immediately redline the engine for like 5 minutes while in park. Just insane. Obviously that's not good, but they needed to know people wouldn't pop their engines if some idiot 16 year old son did that with the family car. There are all kinds of crazy tests the manufacturers do to make sure their cars don't blow up in statistically significant numbers causing excessively high warranty costs.

neanicu

I don't understand why would anyone talk about the engine " blowing up ". That is not the issue. The most likely effect will happen much later in the car's life : like oil burning or loss of compression.
But again,many are not concerned because they are not planning on keeping the car for a long time and they don't care what happens with the car in the 2nd or 3rd owner's hands.

O5C4R

did a super sprint track day today and was slightly quicker in my C2S then a GT4 that was there with only 400kms on the clock, break in for him was drive it like he stole it, he said he was told to bed in the breakes thats all. I was surprised to be quicker then the GT4, but i suspect it was a bit slow because the engine hadn't opened up and its a new car

Tom Tweed

It's highly unlikely that the car was slower because it was new and the "engine hadn't opened up." The difference in performance between a new engine and one fully broken in might be a few percentage points, at most. If the guy was not limiting RPMs for break-in and "driving it like he stole it," as you say, then the simpler explanation is that his driving skills are closer to the average car thief than a racecar driver. An open track day can attract a wide range of skill levels, and if you were faster in a C2S, you are probably just a better driver than him. The GT4 should have a weight, handling, and tire advantage that wasn't fully exploited in this case, I would guess.

C.J. Ichiban

guys thanks for liking the review and being critical of it- I really wanted to do this to have an honest opinion and expected it to have a little back and forth...

THANK YOU A TON for everyone claiming to be a future customer of mine. I will take care of everyone that wants to be taken care of with any of my current dealerships. Adding 1-3 more points in various locations this summer. SUPER EXCITED.

okay in relation to the break in period- I got this GT4 strictly for experimentation for my race team. it will be a track beater for me and as such we will eventually do a 4.0 engine, so the current pistons etc will all be replaced in a few k miles no matter what.

I did break the car in keeping the revs below 4500 for the first 500 miles and I did somewhat break in the PCCB but didn't have time logistically to do the full situation. We will experiment with various components and then return the car to stockish so I can blast around socal next offseason.

we will be announcing soon through our partnership with BBI in OC, a joint venture pairing with CJWR that gets your car closer to the GT4 Clubsport, as such we are working with PFC and all the other race only components to see how long they will last on either/ both applications. there will be a few different options and packages.

slightly OT- in regards to Matt- I realize he is polarizing for the majority of people but that is kind of the point. for the record he took ZERO warm up laps and just went in and drove the cars. unlike a lot of guys who enjoy cars I would not just turn someone loose like that unless I felt like they had a seriously strong sense of car control- which he does.

to be fair the racing seat in the CS is setup for my drivers who are 5'9 and 5'11. Matt is all of 6'4 250. poor guy had to shoehorn into that CS cage. but he is 100% serious in both his criticisms and his love, a lot of journalists will tell you what you want to hear in order to help car companies sell cars (car of the year type stuff especially) but matt is a great guy to spend a few hours with talking cars.

in regards to lap times- none of us had been on streets of willow before and the lack of track run off and tons of rocks everywhere really made it a sketchy experience although it was a lot of fun.

there are a few other publications that will be covering this same subject with my cars in the coming weeks- matt is just the best at turning them around and wanted to beat them all to market.

jalopnik had me drive both cars randy pobst style where I am mic'd up and drive around at 9/10ths. I think I managed a 1:21 or something with a lot of chicken lifting in the race car while talking through the corners...looking forward to that.

I drove the mono home and even had my team do a pit stop on Ventura Blvd right next to the Sherman Oaks Arclight cinema. it's 150-160 miles from Willow Springs to Newport Beach and I had a great time. I have some good videos of driving it up to Bbi in HB the next morning via PCH.

the Mono is awesome- but if you have never driven a formula car it will take some time to get acclimated. It is really really serious and I feel like I'm better off in that thing (when my pit crew is not around) than I am tracking my P1 (although I'm up to 10 track days on the P1 and 2 on the 675LT and 11 on the Viper ACR)