DCT transmission and No lift shift/auto blip Six Speed Manual Mod Hit

[CeeDubb]

It appears an OEM DCT transmission take a -0.5 hit for the HP calculator and a OEM 6 speed no lift shift/auto blip transmission has no mod hit.  Has any data been provided to compare both transmissions side by side to justify the -0.5 hit for a DCT transmission.  

[daytonars4]

We have a couple guys working on DCT swaps on their e36’s now. General thought is it will be about a 1s per lap gain in GTS where there is no mod. Ideally if you can find someone who did a swap to compare before and after data, that’s going to be the most relevant data you can use to gauge “fairness.” 

[Greg G.]

Our info lines up with the 1s per lap (or more depending on the track).  Each class is separated by 2-4 seconds in general--which lines up with a -0.5 Mod Factor (25% of a class jump).

[Bryan Heitman]

So a DCT is a -0.5 factor, what is a sequential worth?

[Greg G.]

The Mod Factor for ST3 & ST4 is -1.0.  So, double the Mod Factor of the DCT.

[joejenie]

That makes no sense.  Sequential is definitely faster than a manual, but similar to DCT speeds (especially if it is a stick and not paddles).  

[Greg G.]

16 hours ago, joejenie said:

That makes no sense.  Sequential is definitely faster than a manual, but similar to DCT speeds (especially if it is a stick and not paddles).  

That might be true for some, but not others, and not when you have a sequential with paddles and motorsports programming.  Either way, we do not want to encourage having sequentials in ST4 that raises the cost of the car by $15,000-$20,000.

[Bryan Heitman]

Got it, I disagree that allowing it but heavily penalizing it encourages a sequential but that’s my opinion. The concern about car counts is interesting since our region has only 2-4 at most anyway, being more open would encourage more cars.
 

 

[hispanicpanic]

DCT's are made in enough numbers to be had for a fairly reasonable price in some layouts.  My data puts DCT's  between .4 and .8 seconds faster than a well shifted H pattern, depending on the length of the straight and number of straights at a track. At lime rock its a whole .4 seconds faster on a ~1 minute lap, with half of that down the main straight.    Not sure how the data behind 1 second was collected but that's kinda off from mine.   I designed a 1 off pneumatic shift system for a sequential with paddle shifters which put it at 90-95% as fast as a dct shift (comparing changes in acceleration change during shift).  Sequentials are significantly lighter than DCT's with nearly as quick a shift and produce less heat, lowering cooling requirements.... but are an order of magnitude more expensive than snagging a DCT from a junked Mitsubishi or other platform. 

 

I suspect whoever "collected" the data that presented it to NASA was sandbagging because he was mad his H pattern car was getting slower compared to the rest of the field. 

Edited February 9, 2023 by hispanicpanic