RPi Stage 3 supercharged - Page 28

5.7 silver bullet · 8th March 2012, 00:47

Quote:

Originally Posted by ACG

Wow this thread evolved in the one day I was gone

Beautiful car you have there Rab Dog.

I agree with a lot that has been said when it comes to trq being a factor in the times but I am only pushing 400trq on the MAHA so I would not expect to beat a lot of cars that come with much more in stock form, also one reason why I do not race against cars I know have tons of trq from a standstill.

Jared I think this kit is as tested as it will be so do not expect any earth shattering news to say they have found the missing reason why this car is not as fast as some expected, I think the cars does very well for it's size being a 4 door. I was actually very proud that it came out unscathed after this past weekend BMW car clinical, it handled admirely

Also on a side note as I know this thread will get buried like the rest but as promised here is the Vbox run from Monday

Yes that's an 8.29sec 60-130mph run
Same elevation as before (a slight incline) and temps around 68F.

Very fast Paul can you give more details on the run and what was done different then last time! Great job!!

Looks like only one shift 3-4th?

ACG · 8th March 2012, 01:05

Yep only one shift like last time as the redline being raised to 8600 just barely let's me get to 130mph.

Changed two things, one I took off at 40mph which helped getting me more momentum to even start the run, second I flicked the paddle shifter instead of pulling it back like I normaly do in day to day driving. On one run it did not recognize the shift as it was too soft so had to put a tad more pressure and it seems to have worked. Honestly we are only talking .6 of a sec improvement here and as you know that goes by really fast

5.7 silver bullet · 8th March 2012, 01:14

Quote:

Originally Posted by ACG

Yep only one shift like last time as the redline being raised to 8600 just barely let's me get to 130mph.

Changed two things, one I took off at 40mph which helped getting me more momentum to even start the run, second I flicked the paddle shifter instead of pulling it back like I normaly do in day to day driving. On one run it did not recognize the shift as it was too soft so had to put a tad more pressure and it seems to have worked. Honestly we are only talking .6 of a sec improvement here and as you know that goes by really fast

You are running the stock 3.62 diff? I do not think I can get there in 4th with the 3.91!! So are you just in 3rd and floor it from 40mph and the hit 4th at 90-98mph. Are you letting it hit the rev limiter?

YOU NOW GET THE TROPHY FOR THE FASTEST 60-130 FOR A M5 EVER RECORDED

NICE JOB!!

tjav8b · 8th March 2012, 01:15

There you go! Nice work Paul. Now we are getting somewhere. That shift still looks really slow compaired to other Vbox spreadsheets. It looks to me like that alone is keeping you from breaking 8 seconds. I am betting you will figure it out and break it. Maybe short shift it at 8k?

ACG · 8th March 2012, 01:18

Quote:

Originally Posted by 5.7 silver bullet

You are running the stock 3.62 diff? I do not think I can get there in 4th with the 3.91!! So are you just in 3rd and floor it from 40mph and the hit 4th at 85-90mph.

YOU NOW GET THE TROPHY FOR THE FASTEST 60-130 FOR A M5 EVER RECORDED

NICE JOB!!

I am on the stock gearing and yes I hit 95mph before shifting.

Just saw your edit, I do not hit the rev limiter......well I have but those runs don't count LOL.

ACG · 8th March 2012, 01:23

Quote:

Originally Posted by tjav8b

There you go! Nice work Paul. Now we are getting somewhere. That shift still looks really slow compaired to other Vbox spreadsheets. It looks to me like that alone is keeping you from breaking 8 seconds. I am betting you will figure it out and break it. Maybe short shift it at 8k?

I am still losing .5 on the shift and that is what is stopping me from getting into the 7s so I am talking to a few shops to see what can be done

, last thing I want to do though is break anything

I have tried short shifting at 8k and it makes no difference, I posted this in my first vbox thread.

duhawks · 8th March 2012, 02:31

Very nice work. I am compairing your numbers to some of the ESS VT2 and VT3 M3 times and really your numbers are great. The guy that ran 6.xx seconds was running 9.5 lbs of boost on race fuel. He even said breaking 7 was only accomplished a few times and it was not easy. For the most part he was running low 7s with 9.5 lbs of boost and race fuel. With 6 to 7 lbs of boost the guy is running 7.4 at his best. How much boost are you running?

Looks like he is just quicker from the start and kills you when you shift. Other than that the numbers are very similiar from 110 to 130.

ACG · 8th March 2012, 05:20

I only run 7lbs of boost and no race gas here. I noticed that even with the shift on the M3 the line does not dip whereas mine sort of stumbles for awhile. Now if that was just as smooth then who knows where it would land.

EuroCarFan · 8th March 2012, 05:24

Quote:

Originally Posted by ACG

I only run 7lbs of boost and no race gas here. I noticed that even with the shift on the M3 the line does not dip whereas mine sort of stumbles for awhile. Now if that was just as smooth then who knows where it would land.

I thought the VT2 is set at 6PSI?

ACG · 8th March 2012, 05:29

Quote:

Originally Posted by EuroCarFan

I thought the VT2 is set at 6PSI?

I thought that was VT1 without the heat exchanger......please do not make me wade through all them threads again

Also I just messed around with the graph and if I continue the acceleration line without the blip from the SMG (similar to the DCT on the M3) it lands around 7.2-7.3 secs