Dosing with a Bottomless Portafilter

[LDT]

The basket that came with the Vivaldi bottomless portafilter with hold a larger dose than the double basket. I have two questions:
1. If you fill the triple basket with say 18 grams of coffee, what effect, if any, does that have on shot timing when compared to dosing the double basket with 15 grams of coffee?
2. If you use the triple basket and dose with 15 grams of coffee would that have a similar, but lesser, effect as having the pre-infusion chamber installed?

[dgasmd]

Having discovered the answer to these 2 questions first hand recently, let me take a stab at it. Others can correct me or expand.

1. The short answer is that it will increase the shot time. The more dosing, the longer the time it will take for the same pre-set volume to go through.

2. Would make no difference. 15 grm on the bottomless or the double would be about the same. At least that is the case with me and I have the pre-infusion chamber in mine as well.

[Endo]

I think the lastest triple dose is about 19g? Am I right?