SONOMA, Calif. – Both Andretti Autosport and Schmidt Peterson Motorsports have announced recent extensions with Honda in multi-year agreements in the Verizon IndyCar Series.

The other three Honda teams – Chip Ganassi Racing, Rahal Letterman Lanigan Racing and Dale Coyne Racing – will also be with the manufacturer into 2018 as well, confirming all five teams stay as is next season.

Honda Performance Development President Art St. Cyr told NBC Sports that while all these teams are confirmed for 2018, their contracts are staggered so that not all teams come up for renewal at the same time.

“Our team lineup is set for next year, so we are keeping the same five teams that we have this year with the latest announcement with Andretti Autosport at Watkins Glen announced that we re-signed them,” St. Cyr told reporters at a media availability Friday at Sonoma.

“So we still have the same five teams with Andretti Autosport, Chip Ganassi Racing, Dale Coyne Racing, Rahal Letterman Lanigan and Schmidt Peterson Motorsports.

“Driver lineup might be a little bit different, but having those teams set right now gives us a chance to really put our plan in place early on to make sure that the off‑season testing will go well, especially with this new universal aero kit, make sure that the information that we can provide for the teams gives them a good foundation for them to launch off next year. Hopefully next year will be even more successful.”

However, what is an interesting thing to note is how many cars those five teams can field.

Combined this year, it was 13 full-time cars – and Andretti, Coyne, RLL and SPM combined to add five extra cars for the Indianapolis 500 for 18 Honda cars. The extra entries were Fernando Alonso and Jack Harvey (Andretti, with other team support from McLaren and Michael Shank Racing), Pippa Mann (Coyne), Oriol Servia (RLL) and Jay Howard (SPM, with Team One Cure).

St. Cyr said the 13-car number is actually two more than its preferable capacity of 11 cars. In 2018, Andretti will field four cars, with the other four teams set to field at least two, and if at least one of them becomes possible to add a third car, that would make 13 again.

“It’s not a simple answer, quite frankly,” St. Cyr explained. “Our capacity, the way that we’re staffed is really for 11 cars. That’s our capacity at HPD.

“Now, obviously we can extend that given the circumstances that we have. We would prefer not to. Quite frankly this year 13 cars really stretched our capability. We wouldn’t be looking to add to that number short‑term. Obviously it’s a physical limitation of our engine build shop just to try to get enough engines through that shop. I mean, as it is right now, we still building Indy engines I think in February, so it becomes a little bit problematic in terms of building enough supply to do that stuff.

“To answer your question about whether we have the capacity or the willingness, we always want to ‑‑ we want this series to grow, so we want more teams, but that’s quite frankly one of the reasons we encourage looking for other manufacturers is to kind of help with that car count, and 13 is really kind of our practical limit that we have right now, so we’re not really looking to expand above that number.”

Andretti Autosport, which has all four of its cars done for the all-American quartet of Ryan Hunter-Reay, Alexander Rossi, Marco Andretti and Zach Veach, is now less inclined to add a fifth car full-time in 2018. Andretti told selected reporters Friday at Sonoma that unless something was to get done in the next couple weeks, that option is highly unlikely.

Still, Andretti expects to have at least five, and potentially six cars in the 2018 Indianapolis 500 – as he did this year with the extra cars run in tandem with McLaren and Michael Shank Racing.

Juncos Racing and Harding Racing both made their Indianapolis 500 debuts this year with Chevrolet, and provided either or both increases their programs beyond their limited entries this year, they’d do so with Chevrolet.

Jim Campbell, vice president, Performance Vehicles and Motorsports, Chevrolet, told NBC Sports at Watkins Glen that Chevrolet has the ability to extend its capacity to double digit cars in 2018, if necessary. This year, Chevrolet has only had eight full-time cars, four from Team Penske and two apiece from Ed Carpenter Racing and A.J. Foyt Enterprises.

Carlin, which has not announced a step-up to IndyCar but has been heavily rumored to do so over the last few months, would then be a potential Chevrolet candidate as well given the potential capacity issues at Honda.

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