Good to see you back here and congratulations for being back in Atom business
There is a thread somewhere in the forum, stating, that Atoms without windscreen kind of "hit a wall" at a certain speed and from this point further acceleration takes plenty of time.
The big windscreen was said to improve the air resistance, so that acceleration at higher speed would be better.
However this thread also mentioned, that the ram air effect to the air intake would be significantly less when having the big windscreen, which would result in a lack of power at higher speed compared to Atoms with gunsights only.
Whatever may be right or wrong...
From my experience also having the wonderful big windscreen
any acceleration beyond 200kph feels a bit time consuming. However this acceleration still is hardly comparable to other cars and my Atom runs 250 quite easily. Admittedly this is according the Spa speedometer and not GPS, but the Atom still accelerates at those speedo 250 and I always had the impression, that I could even hit the limiter in 6th gear.
The 6th gear btw. is no overdrive in the civic, where you hit the limiter at 220kmp (speedo) in 5th gear.
As my basecap does not at all fly away at 250 and because the air appears to nicely be lead over the car I would expect, that an Atom with big windscreen might be slightly faster.
Probably the acceleration at lower speeds is worse because of the higher weight
If your Atom already had problems as n/a I remember a civic, that was not able to exceed 220kph acc. speedo, while all others ran about 245-250 in original spec. This also did not improve by even adding bold-ons like catback and race catalyst. The result on a dyno was about 180bhp(-).
The funny thing about it was, that without changing any hardware between this dyno run and the following ECU adjustment the last dyno after ECU was finally adjusted, showed 220+bhp. So probably a more serious issue with the ECU at that Civic.
As long as you do not have figures to compare the acceleration of your 3-310 and your 2-275 it is perhaps also the missing wind and noise impact, "making" the new one "slower".
I have always remembered, that the passenger drive in your 275 was a lot more spectacular than in my later 300. The driver may had made the difference
but I guess you will experience something similar, when you compare driving with and without windscreen.
. Finally I have to start shifting at the first shiftlight again to avoid hitting the limiter, I missed the beast.
