P-47 max manifold pressure with WEP

[Qcumber]

I am learning to fly the p-47 and have been reading up as much as possible about engine management. From what I have read in Chuck's guide the max manifold pressure with turbocharger maxed out and water\methanol is 64 inches. However, I find that I get 70 inches at these settings (40 version I think) at altitudes from about 7000 ft to about 20000ft (I have not tested higher yet). I understand that in theory field modified versions of later p-47s were potentially capable of up to 72 inches (according to Greg's videos on the p-47). Can anyone explain why I am getting 70 inches?

[saburo_cz]

It is because P-47D's engine isn't equiped with any kind of manifold pressure regulator (boost control).

[Art-J]

^ What Saburo said.

If you fly fast enough (pulling out of a dive at low altitudes for example), ram effect can even boost you up to 75" for a while!

That's a bit risky territory, though, and one needs to keep an eye on oil and carb temps to avoid engine damage. 64 is just rated and safe limit.

Do some "torture testing" yourself and see how far you can push it at various airspeeds and altitudes.

[grafspee]

As long as carb air temp is with in reasonable limits and oil temp in optimal range, engine should be fine for the most time even if you pulling more then 64"

Edited July 29, 2023 by grafspee

[Bozon]

On 7/29/2023 at 7:09 PM, grafspee said:

As long as carb air temp is with in reasonable limits and oil temp in optimal range, engine should be fine for the most time even if you pulling more then 64"

 

“Should” or “is” fine for the most time in DCS?

[grafspee]

10 minutes ago, Bozon said:

“Should” or “is” fine for the most time in DCS?

Hard to answer, depends how you handle engine through out whole flight. From my experience i could boost up to 70" for couple minutes as long carb and oil temp stayed at safe range, engine didn't suffer any failure withing 20min after use. I haven't tested if for longer periods.