[BunkerJ]

Originally Posted by ilivas

That seems to be the sweet spot from what I’ve read. Once you start tearing into the motor or head, things start breaking really quick. I’m not going to make that mistake on this car.

Rods/Rod bolts are the weakest. After building the motor, tranny would be next, but the ZF45HP despite being rated for 337ftlbs, had held up to 500+. Can't say how long that'll hold though.

[rjd_F30]

Originally Posted by ilivas

I knew going into it, there was absolutely no way to make this car fast. You’d be stuck even if you got a 335. I have friends with big singles in their 335s and they’re still left wanting. Apparently, things get really difficult after 600whp. However, at 275whp for me anyways, this car will be very fun and that’s all I want. My corvette is making 800whp and it’s really not that fun on the street unless I have drag radials on the car because all it does is blow the tires off to 100mph. Even then, I’m going for more power and shooing for 4 digits with a built motor. It can never end. My drag radials last about 3k miles of driving and if it rains, I’m screwed. I can’t go more than 10mph in the rain. . That’s why I got this car because it’s comfortable nimble and fun and I don’t have to worry about anything really.

Even if my corvette is making 1000whp, I’m still slow compared to most people in the modding game.

you have to remember that fast is relative. compared to 90% of other cars on the road, a tuned N20 is, in fact, fast. however, when you compare it to a 1000 wheel corvette, it is, in fact, not fast. and no matter what you're comparing it to, my car still puts a smile on my and my friends face when I go WOT. it's all relative, and in most realms of relativity, a tuned n20 is fast. about your friends with big single turbski 335's, after you add a little power, you'll alway want more. if you get used to dailying a 1000hp car, you'll eventually want more because eventually you'll get used to it and it won't feel as fast as it used to. it's allllll relative

[ilivas]

Originally Posted by BunkerJ

Rods/Rod bolts are the weakest. After building the motor, tranny would be next, but the ZF45HP despite being rated for 337ftlbs, had held up to 500+. Can't say how long that'll hold though.

I’ve broken a rear diff on my corvette on a 30 roll at the track, but even a dig. It’s supposedly rated for much more but the track is sticky and wheel hop can kill any tranny.

[ilivas]

Originally Posted by rjdnyy224

you have to remember that fast is relative. considered to 90% of other cars on the road, a tuned N20 is, in fact, fast. however, when you compare it to a 1000 wheel corvette, it is, in fact, not fast. and no matter what you're comparing it to, my car still puts a smile on my and my friends face when I go WOT. it's all relative, and in most realms of relativity, a tuned n20 is fast. about your friends with big single turbski 335's, after you add a little power, you'll alway want more. if you get used to dailying a 1000hp car, you'll eventually want more because eventually you'll get used to it and it won't feel as fast as it used to. it's allllll relative

For sure. I completely agree. People will always want more. That’s my point. My STI that I had before was making just shy of 700 whp, and the powerband, cam, turbo, clutch, etc was just rough. Not meant for street driving at all. It just wasn’t fun anymore. Things broke left and right. So I promised myself if I went for big power, I’ll go the easy route with a v8 and not daily drive it.

Anyways, the point of my post was that I would try to keep it at a power level where things are reliable and the car is still fun and easy to drive. 300 whp seems to be where I’d like to stay.

[Okhan19]

Hey guys new to this forum have a 328 I 2015 with ATM intercooler, AR downpipe and RK ecu tune. How does the data log look to you?

[rjd_F30]

Originally Posted by ilivas

For sure. I completely agree. People will always want more. That’s my point. My STI that I had before was making just shy of 700 whp, and the powerband, cam, turbo, clutch, etc was just rough. Not meant for street driving at all. It just wasn’t fun anymore. Things broke left and right. So I promised myself if I went for big power, I’ll go the easy route with a v8 and not daily drive it.

Anyways, the point of my post was that I would try to keep it at a power level where things are reliable and the car is still fun and easy to drive. 300 whp seems to be where I’d like to stay.

totally agree. I think 300whp is a good mark for these cars. and yah, if you want big power, there's no point in boosting a 4 cylinder through the roof. if you can afford that and everything it implicates, you can afford to go buy a car that was actually meant for it.

[BunkerJ]

Originally Posted by ilivas

I’ve broken a rear diff on my corvette on a 30 roll at the track, but even a dig. It’s supposedly rated for much more but the track is sticky and wheel hop can kill any tranny.

That is exactly what would follow after the motor lol.. Knowing this platform, at the same time!

[BunkerJ]

Originally Posted by Okhan19

Hey guys new to this forum have a 328 I 2015 with ATM intercooler, AR downpipe and RK ecu tune. How does the data log look to you?

Looks good! What's your target PSI for boost? Noticed you only peaked ~19.5.

Also, upload your datalogs (The .csv files) to Datazap.me

It really helps us out! Here is your log: https://datazap.me/u/bunker/log-1523...log=0&data=4-7

[BMWtight2me]

Originally Posted by ilivas

I’ve broken a rear diff on my corvette on a 30 roll at the track, but even a dig. It’s supposedly rated for much more but the track is sticky and wheel hop can kill any tranny.

I snapped my rear axel on a launch — in a 320i targeting 22psi on 100 octane. Things definitely start failing when you push these cars. I’m on my second engine as well!

[Diegov209]

Originally Posted by BMWtight2me

I snapped my rear axel on a launch — in a 320i targeting 22psi on 100 octane. Things definitely start failing when you push these cars. I’m on my second engine as well!

Your scaring me man i always launch my car now you got me paranoid lol. I have question also is anyone going to CMI on April 29 I believe is the date If you are I’ll be their going to take my car to see what times I get lol.

[BunkerJ]

Originally Posted by Diegov209

Your scaring me man i always launch my car now you got me paranoid lol. I have question also is anyone going to CMI on April 29 I believe is the date If you are I’ll be their going to take my car to see what times I get lol.

Would, but way too far lol

[rjd_F30]

Originally Posted by Diegov209

Your scaring me man i always launch my car now you got me paranoid lol. I have question also is anyone going to CMI on April 29 I believe is the date If you are I’ll be their going to take my car to see what times I get lol.

launching is about the most strain you can put on your drivetrain. I only do it when racing. I would cut that down if I were you

[ilivas]

Originally Posted by rjdnyy224

launching is about the most strain you can put on your drivetrain. I only do it when racing. I would cut that down if I were you

It’s not really launching. It’s wheel hop. If you have hard tires. That hurts also. Bias ply tires for the track can save your drivetrain since they have a lot of cushion and give in the sidewalls

As soon as I feel wheel hop, I let off.

[ilivas]

Originally Posted by BMWtight2me

I snapped my rear axel on a launch — in a 320i targeting 22psi on 100 octane. Things definitely start failing when you push these cars. I’m on my second engine as well!

I know the feeling man. At least it was only an axle.

[rjd_F30]

Originally Posted by ilivas

It’s not really launching. It’s wheel hop. If you have hard tires. That hurts also. Bias ply tires for the track can save your drivetrain since they have a lot of cushion and give in the sidewalls

As soon as I feel wheel hop, I let off.

wheel hop is definitely a problem on higher HP cars, but I doubt anyone is getting any on an n20 car. whats bad about launching (especially for xDrive cars) is that, because our cars usually don't make enough power to spin all four wheels, the brunt of the force is placed on the transmission because of the sudden jolt of power. the transfer case is also hurt from launches for the same reason. this is usually an issue on stick cars, but the same logic applies.

although my above logic probably doesn't apply to this: here is an example of what can happen if you launch an AWD car too many times:

[ilivas]

Originally Posted by rjdnyy224

wheel hop is definitely a problem on higher HP cars, but I doubt anyone is getting any on an n20 car. whats bad about launching (especially for xDrive cars) is that, because our cars usually don't make enough power to spin all four wheels, the brunt of the force is placed on the transmission because of the sudden jolt of power. the transfer case is also hurt from launches for the same reason. this is usually an issue on stick cars, but the same logic applies.

although my above logic probably doesn't apply to this: here is an example of what can happen if you launch an AWD car too many times:

For sure. I had an STI and I broke the rear diff a few times. I’m supposed to ride the clutch out on the launch which results in pretty good 60’ times, but I’ve gotten a little excited before and accidentally dumped the clutch at high rpm.

I didn’t even think about xdrive since mine is rwd.

[2015bmw328in26]

Have a 2015 328 n26 xdrive and consistent 4.7 4.8 to 60mph. If that were on a drag strip it would be around 4.5 4.6 to 60 and my 1/4 is 13.2 and 12.9 at a strip. Not the fastest at all but for only having a jb stage 2,afe air scoop and filter, non runflats, lighter wheels, 93 Oct, sport trans programmed lowered and front strut bar it's pretty quick. About 315hp 340ftlbs at the crank. 35k miles and what we are finding out is this engine can increase up to 15% more power as the miles reach 40k. Boost is up 3.5psi. The key to quick times to 60 and the quarter with these cars is to not use the launch control rather launch in manual same way left foot brake revs to 3k then release. Often I only spin the front tires and even torque steer. If wet all four spin for a while. 60 ft time is always 1.8sec.

[2015bmw328in26]

Originally Posted by ilivas

For sure. I had an STI and I broke the rear diff a few times. I’m supposed to ride the clutch out on the launch which results in pretty good 60’ times, but I’ve gotten a little excited before and accidentally dumped the clutch at high rpm.

I didn’t even think about xdrive since mine is rwd.

You will likely never hurt the ZF 8spd as it has been designed for launching and also has dampening spring systems at 2 locations inside the trans to deal with that kind of torque. The same trans handles north of 400ft torque and designed to launch with that amount of torque. Cant comment on the 6spd thou.

[rjd_F30]

Originally Posted by Usmce90n52

Have a 2015 328 n26 xdrive and consistent 4.7 4.8 to 60mph. If that were on a drag strip it would be around 4.5 4.6 to 60 and my 1/4 is 13.2 and 12.9 at a strip. Not the fastest at all but for only having a jb stage 2,afe air scoop and filter, non runflats, lighter wheels, 93 Oct, sport trans programmed lowered and front strut bar it's pretty quick. About 315hp 340ftlbs at the crank. 35k miles and what we are finding out is this engine can increase up to 15% more power as the miles reach 40k. Boost is up 3.5psi. The key to quick times to 60 and the quarter with these cars is to not use the launch control rather launch in manual same way left foot brake revs to 3k then release. Often I only spin the front tires and even torque steer. If wet all four spin for a while. 60 ft time is always 1.8sec.

Originally Posted by Usmce90n52

You will likely never hurt the ZF 8spd as it has been designed for launching and also has dampening spring systems at 2 locations inside the trans to deal with that kind of torque. The same trans handles north of 400ft torque and designed to launch with that amount of torque. Cant comment on the 6spd thou.

first: time slips/video or it didn't happen. claiming a 12.9 quarter for an n20/6 car with those mods is a very bold claim.

regarding launching, I disagree. the ZF 8HP45 in the 328i is stout for what it is, but has a relatively low torque rating, and no matter how well deigned, no transmission is built to withstand the constant and repeated stress of launching. I don't feel like fact checking the "2 springs for dampening" thing, but I haven't heard of that before. very well could exist and I just don't know it though. also, more than worrying about your trans, you have to worry about your transfer case in an xDrive car, as demonstrated by the EVO video above.

[ilivas]

Originally Posted by Usmce90n52

You will likely never hurt the ZF 8spd as it has been designed for launching and also has dampening spring systems at 2 locations inside the trans to deal with that kind of torque. The same trans handles north of 400ft torque and designed to launch with that amount of torque. Cant comment on the 6spd thou.

A 1.8 sec 60’ isn’t really that hard of a launch. That’s a relatively soft launch.

[rjd_F30]

Originally Posted by ilivas

A 1.8 sec 60’ isn’t really that hard of a launch. That’s a relatively soft launch.

I was brake boosting up to 3k-ish rpm and dumping the brake on full throttle. it's about as hard as I could launch it, or at least as hard as I thought I could. that might not sound like a hard launch just by the numbers, but considering the power levels we're talking about here, I think thats a pretty hard launch.

[BunkerJ]

Originally Posted by rjdnyy224

I was brake boosting up to 3k-ish rpm and dumping the brake on full throttle. it's about as hard as I could launch it, or at least as hard as I thought I could. that might not sound like a hard launch just by the numbers, but considering the power levels we're talking about here, I think thats a pretty hard launch.

If you aren't launching at 6k, you're wrong.