seems two of the +7 turbines require slightly more steam than a +7 heat-exchanger produces? can it be made equal?

First of all, are you using them with my pipe +7 and heat-pipe +7?
It sounds like you are facing throughput limitation from fluid system. And my fluid-involving machines (with tier +4 and above) are only meaningful if paired up with my scaled-up pipes in Schall Pipe Scaling. Pipes of vanilla or other mods may not provide adequate throughput.

And please provide a screenshot and/or some details of your setup. Without info, I cannot judge whether it is a design problem, game limitation problem, or my mod's problem.

By definition, this mod will always have the fixed multiplier 4^tier over vanilla tier. No special tuning on specific machine/tier will ever be considered.

i'm talking about the actual outputs, i don't have any pipes involved - it's just a heat exchanger with two turbines off of it. everything is the highest tier

Four reactors in a square,

+7 Heat pipe bus coming off two of them

+7 heat exchangers on either side of +7 heat pipe

2x +7 steam turbines off of a heat exchanger

https://i.imgur.com/EZUD5CJ.jpg

https://i.imgur.com/IXo3BiJ.png

at idle it says a full ~95.4 is available, but since the Heat exchanger produces 1.7M/s steam and these require 1.97M/s steam, the available falls to something like 68GW when running full tilt.

https://i.imgur.com/lkVQjLR.png

It looks similar to my design in Schall Pipe Scaling FAQ.
I just tested mine on 1.1.30 and it seems working at stated full rating when sustained. (Actually showing 2.0 TW, perhaps used round up in recent game versions.) I do not see any problem in it.

• Nuclear Power +6 2×2
  Theoretical Rating: 1996.08 GW
  Actual Rating: 1.9 TW
  Blueprint string
  

Vanilla heat exchanger consumes 10 MW (hence 103/s steam output).
Vanilla steam turbine consumes exactly 60/s steam (hence 5.82 MW).
This gives the official Wiki stated ratio of 1.718 turbines per exchanger.

My +7 machines are simply 4^7 = 16384 times over that.
Heat exchanger +7 consumes 163.84 GW (hence ~1.7M/s steam output).
Steam turbine +7 consumes exactly 983040/s steam (hence ~95.354 MW).
Therefore, it is simply the same as the vanilla ratio.

Are you having some misunderstanding of vanilla nuclear ratios? (1.718, not 2)
OR are you suggesting me to apply a DIFFERENT ratio from the vanilla? (Not purpose of this mod.)

no, i will have to put together a save file with only your mods that demonstrates the issue.

the prototypes that it seems to be based on are incorrect. i don't want anything other than vanilla specs for the reactor. i just want it to output what it promised to without having excessive heat exchangers.

Can you try my blueprint first?
If it gives sustained 1.9 TW, then maybe something missing in your design.
If it does not give sustained 1.9 TW, then maybe some mod(s) in your mod set has change the specs.
Have to isolate the cause first.
(If you do not have enough items/resources, Creative Mod and/or Waterfill mods can help.)

how can my mods change the spec but not be listed in the prototype history?

https://i.imgur.com/mfQHh9z.png

https://i.imgur.com/fDtIGXO.png

you can see it actually starts at 2.3TW and then reduces. the loss from 2.3TW to 1.9TW or 2.0TW (as seen here, rounding thing?) is 300GW+ and a bit more than margin of error imo

https://i.imgur.com/ICNimMc.png

here is one turbine stats during runtime. what does yours look like? mine looks like it has capacity unavailable.

just to clarify i'm fine if the overall capacity of my setup is reduced just so long as the ratios are all closer to perfect ;-)

how can my mods change the spec but not be listed in the prototype history?

An older version of Deep core mining has broken one of my mod and every mod that are using vanilla mining drill graphics. It changes a global function instead of directing changing specs, thus somehow not listed in the prototype history. So it is rather rare, but still possible.

you can see it actually starts at 2.3TW and then reduces. the loss from 2.3TW to 1.9TW or 2.0TW (as seen here, rounding thing?) is 300GW+ and a bit more than margin of error imo

Seems like you still don't understand the nuclear ratios, nor my previous statements...

Because both of our designs are applying 2 turbines per exchanger, which is in EXCESS of what the heat exchangers (and reactors) can provide sustainably. Therefore, the peak is at 2.2885 TW, but only sustained 1.966 TW after consuming the excess steam.
If you really want minimal number of entities, the optimal ratio is 1.718 turbines per exchanger. The amount of machines would be
Reactor +6 : Exchange +7 : Turbine +7 = 4 : 12 : 20.6 (21), or
Reactor +6 : Exchange +6 : Turbine +6 = 4 : 48 : 82.5 (83).

It is IDENTICAL to vanilla nuclear ratios, so really nothing to fix/change.