Modded 35is, Rolling Road Results

Twin Turbo · Post by **Twin Turbo** » Mon Apr 03, 2017 6:48 pm

I am really pleased for you, great result - there might be another Z4 as quick as mine

Love to see you do some power runs.

bmw>benz · Post by **bmw>benz** » Mon Apr 03, 2017 7:42 pm

Are you running any transmission tune?

I have a 14' 35is with 15k miles. After throwing on a JB4, intake, and e30 mix I am getting some considerable slippage in 6th gear applying full throttle at 3k rpm. It appears that I need to get a tune for the DCT to compensate.

elevensies · Post by **elevensies** » Mon Apr 03, 2017 7:54 pm

no thats about right on the rolling road

some rolling roads are what they call tight, where the load on the car is heavy, and shows up all the losses a mag type rolling road wouldnt,
so yeah, rear wheel drive, thats pretty close to correct losses on a good rolling road imho

iv had engine dyno on my race car at 615, and shown 418 on rear wheels before now

elevensies · Post by **elevensies** » Mon Apr 03, 2017 7:54 pm

oh and thats a ace result by the way

Twin Turbo · Post by **Twin Turbo** » Mon Apr 03, 2017 8:12 pm

Arrrrrrrrrrrrr!!!!!!!!!!!!!!!!!!!!

You making me so jealous- starting to considering too upgrading my 4 pott for an 35is

And hitting 400+ BHP

jleckenby · Post by **jleckenby** » Mon Apr 03, 2017 9:55 pm

bmw>benz wrote: ↑Mon Apr 03, 2017 7:42 pm Are you running any transmission tune?

I have a 14' 35is with 15k miles. After throwing on a JB4, intake, and e30 mix I am getting some considerable slippage in 6th gear applying full throttle at 3k rpm. It appears that I need to get a tune for the DCT to compensate.

None at all, running spot on here. Sorry I cant be of more help!

jleckenby · Post by **jleckenby** » Mon Apr 03, 2017 9:56 pm

Twin Turbo wrote: ↑Mon Apr 03, 2017 8:12 pm Arrrrrrrrrrrrr!!!!!!!!!!!!!!!!!!!!

You making me so jealous- starting to considering too upgrading my 4 pott for an 35is

And hitting 400+ BHP

Do it do it!

GuidoK · Post by **GuidoK** » Mon Apr 03, 2017 10:57 pm

R.E92 wrote: ↑Sun Apr 02, 2017 12:07 pm There's something wrong with the dyno if you are making 438 at the crank but only 295 at the wheels. That's a 30% drivetrain loss!
Did they do something stupid like calculate the power using the manual gear ratios not the DCT?

With 100 dyno brands there's usually 100 different results regarding that.
I'd love to see a 100-200kph pull on a flat road timed with a 10hz gps.
A 0-100kph (0-62mph) takes more of the car weight in consideration, but with these power levels its virtually impossible to get consistent low times due to traction problems in 1st

R.E92 · Post by **R.E92** » Tue Apr 04, 2017 8:28 am

bmw>benz wrote: ↑Mon Apr 03, 2017 7:42 pm Are you running any transmission tune?

I have a 14' 35is with 15k miles. After throwing on a JB4, intake, and e30 mix I am getting some considerable slippage in 6th gear applying full throttle at 3k rpm. It appears that I need to get a tune for the DCT to compensate.

You should have done some research on what you were buying. You only have to google "JB4 and DCT" to see that there is issues there.
The JB4 is a piggyback unit, not a proper tune. You really need to remove the JB4 from your car before you end up with an expensive DCT replacement bill. Get yourself a proper tune like MHD.

lordgrover · Post by **lordgrover** » Tue Apr 04, 2017 8:52 am

Surely though, a rolling road dyno measures the power at the wheels, and back-calculates for the crank figure?

R.E92 · Post by **R.E92** » Tue Apr 04, 2017 9:22 am

lordgrover wrote: ↑Tue Apr 04, 2017 8:52 am Surely though, a rolling road dyno measures the power at the wheels, and back-calculates for the crank figure?

Yes you're correct. I think the problem with this dyno is that has measured the power created at the wheels without compensating for losses internally on the dyno. Then when calculating the crank figure they add all the losses back on hence why the crank figure is correct but the wheel figure is massively out.

I follow Guido's opinion that 100-200 (or 60-120) GPS verified times are much more relevant as a measure of performance. Dynos give such wildly varying results between brands.

sunnydays · Post by **sunnydays** » Tue Apr 04, 2017 10:08 pm

Any chance of some performance numbers OP? Numbers seem to be rare for these cars when mapped,

0-60, 0-150 etc.... Even a 1/4 mile time would be fantastic (If you can of course!)
Would really appreciate it!

jleckenby · Post by **jleckenby** » Thu Apr 06, 2017 7:34 pm

Will see what I can do. I know it takes me under 2 seconds to do 30-60!

Brasseye · Post by **Brasseye** » Thu Apr 06, 2017 7:40 pm

jleckenby wrote: ↑Thu Apr 06, 2017 7:34 pm Will see what I can do. I know it takes me under 2 seconds to do 30-60!

Are you sure ?

With all that weight ?

Twin Turbo · Post by **Twin Turbo** » Thu Apr 06, 2017 8:53 pm

jleckenby wrote: ↑Thu Apr 06, 2017 7:34 pm Will see what I can do. I know it takes me under 2 seconds to do 30-60!

Go to York race way - as that local to you - and I hope you can arbitrate my personal best

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