CORDY

HI GUYS

PLS ADVICE THE BEST PROP SIZE FOR GP F4 PHANTOM WITH OS 91 FX

THANKS

Razor-RCU

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Try a search on here, I know I have seen threads about this combo-

LUDS96

My Feedback: (23)

I'm Running a 11x9 on my cermark F-16 with ST 90 with tuned pipe! I'm going to try the same with my F-4 when it get's finished!

Razor-RCU

My Feedback: (50)

Jett-90 or a 90 sized DF engine would work the best-

Strykaas

Incomplete question. If you have a short runway, then a large prop would suit. If runway length is not an issue, you can use smaller props.

If u are looking for top end speed, reduce the diameter, increase the pitch, and use a tach so that your 91FX revs at around 15000 (I guess ?).

CORDY

ACTUALLY I AM USING 13X8 WORK FINE BUT NOTHING IMPRESSIVE.
JUST WONDERING IF OTHER PROP WILL WORK BETTER IN TERMS OF A GOOD SPEED/PULL BALANCE . ALSO DO NOT WANT TO SACRIFICE PULL IN ORDER TO INCREASE SPEED BECAUSE THEN RUNWAY LENGTH WILL BE AN ISSUE.

THANKS TO OTHER REPLIES

Strykaas

Did u tach your 13x8 ? If u want to optimize your prop setup, it's pretty essential...

CORDY

WILL TACH THE 13X8 , AND WILL INFORM FOR FURTHER ADVICE

THANKS

Rudeboy

I'd go smaller than a 13"... I don't have a GP F-4 but I'm pretty sure you will get enough pull from a 12 incher... so slap on a 12x8 or a 12x9 and try her out...

Kaos1

Shucks,

I used to run a Rossi 61 w/ pipe on my GP Super Kaos with APC 12X10 and tack in the 12K range on the ground with lots of pull. Enough pull to haul that 9 lbs straight up! [sm=rolleyes.gif] With the 91 I think that you have plenty of room to play with.

LUDS96

My Feedback: (23)

Don't Rule out that 11X9 APC My F-16 Pulls Great with it !

Razor-RCU

My Feedback: (50)

My Cermark F-20 (60 sized-) flies well with an 11x9 apc-

What is the all-up-weight of the F-4?