Design Increase

I don't get how the design % for new parts is worked out. 

Last season level 8 Cheif Designer I was getting 14% improvement on parts.
This season level 9 Cheif Designer I am getting 3-7% improvement. 

I have the same number of designers giving new parts every 48Hours. 

Why is this?
Is it due to my parts on this years car (70%+) being better than last years (~35%)? 

It is dependant on the development level of your parts. If chassis is 35%, and you put 27 designers, it may increase 10% or more, but if it's 75%, 27 designers will only give a single digit increase.

Since you have a 70 odd percent car you should be working mostly on next season
The position of the slider has big a impacted,
Not sure how the increase is worked out I never pay much attention to it.

All on this season you would see this.
This season performance: Sidepods (+11%), Front wing (+10%), Rear wing (+11%), Underbody (+8%)

Next season performance: Sidepods (+2%), Front wing (+2%), Rear wing (+2%), Underbody (+2%)

All on next season you would see this.
This season performance: Sidepods (+1%), Front wing (+1%), Rear wing (+1%), Underbody (+1%)

Next season performance: Sidepods (+11%), Front wing (+10%), Rear wing (+11%), Underbody (+9%)

In the middle
This season performance: Sidepods (+7%), Front wing (+7%), Rear wing (+7%), Underbody (+5%)

Next season performance: Sidepods (+8%), Front wing (+8%), Rear wing (+8%), Underbody (+6%)

Results above are based on 54-67% car with 16 designers on each part

Sorry I should have said, both are for full development on next years parts. 

obviously all starting on 1%

It depends on this seasons car, exactly like you said.

Simply said, the higher the design of this season car gets, the lower the design updates will be.

So my current car is well design, all my staff are working on the next car but because my current car is good my designers are incapble of designing the next car.

I don't get why current car design level effects the start ability of the design team for the next car.  

"I don't get why current car design level effects the start ability of the design team for the next car"  this is to stop someone from totally dominating season after season from start to end.  I usually stop dev work on the following season at about 50% or less and then full on the current season.  I sometimes clone, if it's worth the jump, but only once I've finished on next seasons car %.  I like to start the season with a car that has at least 60-65%.  I don't win right out of the box but I have a good start for the following season and I can catch up with cloning if I'm getting totally spanked in races once the following seasons car is on course.

Cheers Duncan, that makes sense and why the team who won last season (100% on all parts) are doing so bad this time around. 

I'll get Test rig and Wind Tunnel in about a week. What kind of improvement do I have to expect?
a.) Need less designer to develop a certain part.
b.) Higher performance increasement per development step.

Cole, your development speed will increase to every other day. I have just recently got both myself and rather than waiting 3-4 days for improvements you'll get updates every other day!

Ehhr, Tim, I am in a daily racing league. That means, I need only "few" designers to finish a certain part. If the majority of my staff would be designers I could finish every part every day! But since you can only develop a certain part every 48h, I have to swap my designers every day:
- Day 1 part 1+2+3, finished on Day 2
- Day 2 part 4+5+6+7, finished on Day 3
- Day 3 part 1+2+3, finished on Day 4
- and so on

That means, with Test rig and Wind Tunnel I won't finish parts quicker since I am already at the 48h limit on all parts all the time.
So, Tim, you basically confirmed a.)
What about b.), tho?

Hi Cole,

I got higer development after getting them, also only need 14-16 staff per part to develop every other day. 

The test rig and wind tunnel speeds up design like Anteney said.
As long as chief designer has 20 experience you will get the maximum percentage increase available.

lowest possible staff members is 60 once you have all the facilities
50-60% 11 staff members
70-80% 12 staff members
90-100% 14 staff members
100% 15 staff members to keep working on next seasons car using your system 3 parts one day 4 the next day :)

Great info in this thread.  I want to make sure I'm understanding this right based on your most recent post James.  What I'm getting is that you really don't need more than 60 designers because with 15 on each part (4 maximum) you can reach 100%?  So if I have 82 designers it's pretty much overkill and I'd be better off decreasing to 60 and saving money on staff salaries?

No Derek, it depends.

The percentages James stated is not what you reach, but what is the design of a certain part. And this applies to DAILY racing leagues only.

Example:
My Front Wing is right now at 84%. That means, I need 12 designers to level it up by tomorrow. But, since my design is already high, I get very little increase, like 1% for this and 5% for next season (bar at most right: Design Emphasis - next season).

Never in ever will that add up to 100% for next season! If I get 5% every second day, in a season that is only 18 days long, that is 5% * 9 = 45%!
Plus trainging design everytime, plus one 1% at the start is 45% + 17% * 1 + 1% = 63%

In sum, having a 80% at start of a certain season, gives u a 60% car next season.

Thanks for the response Cole!  So I'm thinking my best bet would be to have the maximum amount of designers after mechanics and engineers are sorted, then spread them evenly using the rotation schedule you posted above.