[Daveslaine3827]

It's crazy that the STOCK Z4 M40 produced around 380-400whp yet my M235 which it and the M2 have been named number 1 car since 2015 until I think 2018, the 235i only had 377whp even at the HIGHEST JB4 MAP.

I tried Map 1 on jb4 on z4 and got around 425whp and at Map 5 with 40% e85 I went up to around 470whp identical to the base current M4 G generation.

Idk how car and driver always get amazing 0-60 times including 3.7 for the z4, but in my case, there's so much power I got a LOT of wheelspin.

Honestly if the z4 had AWD even accounting for some extra weight I have no doubt that at Map 5 with 40% e85 pushing 470+whp and 500 ft lb torque, I'd easily get 3.2-3.4 second 0-60

This car and engine is a beast

[BEAR-AvHistory]

Roll out is how the magazines test the standing start. Its a 1 foot dead zone between where the car is standing & the clock start trigger. Typically worth .2 or .3 seconds on a street car. What they are doing is simulating a drag strip starting light configuration. The staged lights, where the car is stopped to launch from & the clock start/foul light is spaced 1 foot apart.

So yes the car is actually rolling when the timer starts in a magazine test.

Example:





When you roll up to the line the pre-stage lights will turn on. You creep forward till the staged lights turns on. The tree will start the countdown .5 second per amber light. Green is the launch light. (any hope of winning you learn how to launch on the last amber) The car rolls forward & trips the timer start light. (the roll-out)



Z4 Dragy runs showing roll out (C&D) type number 3.99 & street start actual time 4.31. Best run so far with roll out C&D style 3.71 - street actual 4.01

Notice the 4.31 run is going up a grade while the 4.01 run is over a slight down grade.

[BEAR-AvHistory]

One other thing C&D uses traction compound on their tests. Have seen pictures of it on occasion. They will make any number of runs to get the best time using various launch techniques. LC no LC different RPM starts etc.

In other words they beat the S**T out of the car to get the best possible number.

Its hard for a civilian to get an optimum launch. If its hot enough to get the street & tires warm the turbos take a hit. Nice cool turbo inlet air means the streets are cold.

I always get launch slippage, 1/2 shift slippage & 2/3 shift slippage. Very occasionally will everything come together. That said have not yet put the street launch number in the 3's with my pure stock Z4.

COBRA is a lot quicker so I will not be tuning the Z4. Still running a JB4 on the 135is. 2011 335is was a JB4, 2014 435 was Factory MPPK, 2018 440 was Factory MPPSK.

[Daveslaine3827]

Originally Posted by BEAR-AvHistory

Roll out is how the magazines test the standing start. Its a 1 foot dead zone between where the car is standing & the clock start trigger. Typically worth .2 or .3 seconds on a street car. What they are doing is simulating a drag strip starting light configuration. The staged lights, where the car is stopped to launch from & the clock start/foul light is spaced 1 foot apart.

So yes the car is actually rolling when the timer starts in a magazine test.

Example:





When you roll up to the line the pre-stage lights will turn on. You creep forward till the staged lights turns on. The tree will start the countdown .5 second per amber light. Green is the launch light. (any hope of winning you learn how to launch on the last amber) The car rolls forward & trips the timer start light. (the roll-out)



Z4 Dragy runs showing roll out (C&D) type number 3.99 & street start actual time 4.31. Best run so far with roll out C&D style 3.71 - street actual 4.01

Notice the 4.31 run is going up a grade while the 4.01 run is over a slight down grade.

When you say roll out does this mean I just let the car inch forward and suddenly press the throttle?

Anyway if that's true then my 3.7 second time WITH WHEELSPIN that easily cost me a few tenths of a second is really really good. I wish I had an xdrive I don't care about drifting I care about precision and grip and going fast from a dead stop.

[BEAR-AvHistory]

Originally Posted by Daveslaine3827

When you say roll out does this mean I just let the car inch forward and suddenly press the throttle?

Anyway if that's true then my 3.7 second time WITH WHEELSPIN that easily cost me a few tenths of a second is really really good. I wish I had an xdrive I don't care about drifting I care about precision and grip and going fast from a dead stop.

No it means once you hit the throttle the car will move forward about a foot or .3 seconds before the timer starts.

[TAZ007]

Originally Posted by BEAR-AvHistory

One other thing C&D uses traction compound on their tests. Have seen pictures of it on occasion. They will make any number of runs to get the best time using various launch techniques. LC no LC different RPM starts etc.

In other words they beat the S**T out of the car to get the best possible number.

Its hard for a civilian to get an optimum launch. If its hot enough to get the street & tires warm the turbos take a hit. Nice cool turbo inlet air means the streets are cold.

I always get launch slippage, 1/2 shift slippage & 2/3 shift slippage. Very occasionally will everything come together. That said have not yet put the street launch number in the 3's with my pure stock Z4.

COBRA is a lot quicker so I will not be tuning the Z4. Still running a JB4 on the 135is. 2011 335is was a JB4, 2014 435 was Factory MPPK, 2018 440 was Factory MPPSK.

I agree, if I had a 427 Cobra; I would not need to tune any other car either.

[BEAR-AvHistory]

Originally Posted by TAZ007

I agree, if I had a 427 Cobra; I would not need to tune any other car either.

https://youtu.be/_fJysY168Zk

Burning some 100 octane, volume up.

[TAZ007]

Originally Posted by BEAR-AvHistory

https://youtu.be/_fJysY168Zk

Burning some 100 octane, volume up.

Sounds good. My 1980 vette has 4into1 4-in side pipes on that L48. Cam changed for power. It sounds like a big block. I am curious on the timing of your cam. It's idle is long and rhythmic.