- Awesomatix A700 Evo - Torsional Stiffness -


by Oleg Babich


I have measured the actual torsional stiffness (stiffness at twisting) of A700 Evo frame (with FFG installed) at different combinations of chassis, AM30-1 stiffener and C21 top deck.
The torsional stiffness of the frame region between the rear AM01 and front FFG bulkheads was measured.

Two variants of C21 top deck were used: the standard C21 and Cut C21 (with removed rear crosspiece).

Four variants of AM30-1 installation on C01AL chassis were used:
a). AM30-1 stiffener fully screwed with 5pcs of SF3x6 screws.
b). AM30-1F: AM30-1 screwed with the central SF3x6 screw and two SF3x6 screws in the front end holes. One SS3x8 set screw (grub screw) was used in the rear end hole of AM30-1.
c). AM30-1R: AM30-1 screwed with the central SF3x6 screw and two SF3x6 screws in the rear end holes. One SS3x8 set screw (grub screw) was used in the front end hole of AM30-1.
d). AM30-1C: AM30-1 screwed with the central SF3x6 screw only. Two SS3x8 set screws (grub screws) were used in the rear and front ends holes of AM30-1.

C01L chassis with FFG but without top deck was used as the reference point ( 100% of torsion stiffness).

The results:

1. C01L 3mm carbon chassis, no top deck: 100% ( reference point)
2. C01L 3mm carbon chassis + Cut C21 top deck: 141%
3. C01L 3mm carbon chassis + C21 top deck: 146%

4. C01AL alloy chassis, no AM30-1, no top deck: 110%
5. C01AL alloy chassis + AM30-1C, no top deck: 110%

Please note: AM30-1C variant of stiffener installation doesn’t increase the torsion stiffness and equals “no AM30-1” in terms of the torsional stiffness influence.
But AM30-1C increases the longitudinal stiffness for sure ( very positive influence) and is used as the inner battery holder also.
So I prefer to use AM30-1C on the car instead of “no AM30-1”.

6. C01AL alloy chassis + AM30-1F, no top deck: 126%
7. C01AL alloy chassis + AM30-1R, no top deck: 126%
8. C01AL alloy chassis + AM30-1, no top deck: 145%

Please note: AM30-1F and AM30-1R variants of stiffener installation provide the similar final torsional stiffness effect.
The difference is only in the distribution of the stiffness along the chassis but it is beyond of this investigation.

9. C01AL alloy chassis + Cut C21 + AM30-1C: 150%
10. C01AL alloy chassis + C21 + AM30-1C : 155%

Please note: the removing of the rear crosspiece on C21 top deck ( Cut C21 variant) reduces the overall stiffness on ~ 5%.

11. C01AL chassis + Cut C21 + AM30-1F or AM30-1R: 168%
12. C01AL chassis + C21 + AM30-1F or AM30-1R : 173%

13. C01AL chassis + Cut C21 + AM30-1: 197%
14. C01AL chassis + C21 + AM30-1: 202%

15. C01AL-H hard coated chassis provides ~ +5% increased stiffness at all mentioned combinations for alloy chassis.

Please note that C01Al/C01AL-H + AM30-1 + C21 combinations provide very wide range of the torsional stiffness ( torsional flex) for A700 Evo car.

It will be very interesting to compare the layouts with the similar flex provided by different elements at track tests , for example:
“ 3. C01L 3mm carbon chassis + C21 top deck: 146% “ and “ 8. C01AL alloy chassis + AM30-1, no top deck: 145% ”
or
“ 8. C01AL alloy chassis +AM30-1, no top deck: 145% ” and “ 9. C01AL alloy chassis + Cut C21+AM30-1C: 150% ”


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