My Fokker DVII Project - Page 115

franzkait · 23 July 2008, 04:42 AM

the GQ 30 is already very complicated to convert for a D7 , the GQ 70 is more complicated . No question , for a D7 I recommend the GQ 30 . To convert the GQ , you need a real machine shop , and not a garage with a drill press ! To many parts have to be made or changed .

gipsymoth236k · 23 July 2008, 04:53 AM

Hello Again Franzkait,

I know that you studied and therefore have much research information for D.VII bottom wing compression ("box" or "doubler") rib dimensions. Can you tell us what width dimension you have found for these particular bottom wing compression ribs? Perhaps 22.4mm or 32.4mm?

Thanks, Gary Sewall

Jeff Brooks · 23 July 2008, 05:21 AM

I know there have been many Ranger engine conversions, with various differences in the method of inversion. Many of the modifications worked fine on some and not so fine on others. Many Ranger inversions are plagued with overheating problems that are not discovered until well after the engine is in the plane & has been running a while. And the Ranger engines are plentiful enough to buy another core cheaply and try again.
From what little I know of inverting a Gypsy 30 ... there have only been a few attempts at inverting them. I understand that there is no book documenting how to invert the engine, like Stanley Morrell's book. You are in uncharted waters.
The only attempt of inverting the Gypsy 70 I know of is Pavel, and I would wait until it has been running a while before I invest in it. I am watching Pavel & Troy to see how their particular projects turn out. I may switch engines once I see which performs better.
I agree with Udo, you need a real machine shop to modify the engine, and you also need a very intimate knowledge of how the engine works. The particulars of the oil flow, and the effect of rerouting it!

Maxim08 · 23 July 2008, 05:40 AM

Jeff,
I believe that Javier inverted the GQ in his Blue Max D VII several years ago.
Regards,
John

Jeff Brooks · 23 July 2008, 06:31 AM

has this GQ 30 inversion been documented to share with others? how does it run? any problems?

franzkait · 23 July 2008, 06:40 AM

his Blue Max D7 has a GQ 6 , look in the movie the top valve covers !!!!

Von Writter · 23 July 2008, 07:47 AM

I believe the Blue max plane had a Ranger in the movie, definatly wasn't inverted as the prop flange came out the top of the rad.

franzkait · 23 July 2008, 08:10 AM

there is not only one Blue Max D7 ! not all are inverted , but all are fantasy D7s .

buck toenges · 23 July 2008, 10:27 AM

Chuck Wentworth did the inversion conversion. I talked to him about it last year, mainly about not getting too much oil up in the rocker boxes. I don't have the were-with-all on the engine so if any of you guys can contact him on his thoughts and can ask the right questions please do. I think Chuck is the main man in Javier's jasta/squadron.

wd6bor · 23 July 2008, 01:00 PM

Buck,

Thanks for the reply. Do you know where I can find published information for the Gypsy Queen engines?

Darrel