Dual lamp hood by sunlight supply

[Soilless]

Hi all, first post here looking for input.
I have for years been running a dual 400 setup. Both lamps are under one hood (sun system)and mounted on each end horizontally. Both run off the same ballast with dual inputs.
There is about 4 inches gap in the center of the hood between the tips of each bulb.

I have just bought a 600w ballast and lamp hps that I want to replace the 400 hps currently in the fixture. I know I can still use the existing socket and cord.
Questions surround whether or not closing the gap between the 2 bulb tips will cause an issue like an explosion. I assume this gap between the 2 bulb tips will go from 4 inches or so to around 2 inches depending on how much longer the 600 bulb is vs the 400.

Anyone see any issues with this change?
Thanks in advance and hopefully this will suffice as a first post here.

 

[Soilless]

No one?
The basic question is how close can the ends/tips of 2 bulbs safely be from each other ?

 

[BPK GrowOp]

I wouldnt think there would be an issue. HIDs are meant to run at really high temps and not be air cooled. So considering yours are in a hood thats probably air cooled you should be ok. Just make sure youve got enough air flowin!

 

[Soilless]

They are not closed cooled with ducting, but I do have a wall mount cyclone currently angled and cooling the 2 in there. Max temps I ever see now are mid 70s. If it gets too hot with new bulb, I can just up the exhaust out of the room, so heat is not an issue, but rather proximity of the two bulbs.

I have seen a smaller 400MH bulb at Lowes that is a few inches shorter and smaller diameter than the typical 400MH, may put that on the other side just to keep a little space.

The dual spectrum 400s have been wonderful and bountiful, hoping to see the proclaimed difference with replacing the 400HPS with the 600HPS.

 

[BPK GrowOp]

Most peoples trouble is fitting all the lights in one place or the heat and if you have those under control i figure itd be good to go.

Just think of stadium lights. They stay on for hours and hours and arent cooled.

I havent grown with the mixed spectrum but have always wanted to and now that ive switched to LEDs theres no turnin back.