4x5 C-41 in 3010 - prewet or preheat (or both)?

[LF_rookie_to_be]

OK, this has probably been talked about a few times already, but it seems there are too many variables to have just one definite answer. Here it goes... Equipment: Jobo 3010 drum, Tetenal C-41 minilab chemicals (3-part dev, dev starter, bleach, C-41/E-6 fixer, 2-part stabilizer), Fuji 160S expired 2010. Requirements: Finest possible grain, no streaks at all, no color cast. I don't have a CPA, CPP or a roller base. What do you recommend? Preheating the drum, two prewets and 'drift through' temperature technique all cropped up as possible solutions. Any and all answers are welcome. Thanks.

[polyglot]

2 prewets for at least 5 mins total (drum spinning in 38C water) and spin the drum at about 50rpm (once per second) in 38C water, reversing every 2-3 revolutions while developing. If you don't have a base, use a BIG sink of water and use the tank's buoyancy. Be careful that it stays level though or you will underdevelop one end of each sheet.

[LF_rookie_to_be]

So prewets and a water bath with a constant temperature are what's really important. Thanks for the answer.

[polyglot]

Yes; the prewets are necessary to bring all the tank internals to temperature. Less important with a 3010 (which has an internal water jacket - note the drain slots on the bottom) than with spirals, but nevertheless helps a lot with consistency.

[Ari]

I presoak at 40˚C for only one minute, but I use a 2553 on a motorized base.
The instructions that came with the Tetenal advise that amount of time, but to fill the tank completely.

[alps-art.ch]

Manual for Tetenal Colortec C-41 says, in General instructions" section, p.7:

If development is uneven (sheet films), it is recommended that the rotation speed be
increased and/or the film be pre-washed for two minutes at process temperature.