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Engine basics => Engine set up tips => Topic started by: Chris Gilbert IRL-1638 on June 26, 2007, 06:26:28 AM

Title: Tank size for St60
Post by: Chris Gilbert IRL-1638 on June 26, 2007, 06:26:28 AM
Hi Guys,

I need a ball park capacity figure for a tank for an ST60.

I expect to be running it on 25% castor and 5% nitro or so, and I need it to run for around 7 mins (F2B).

I'm guessing 4 oz (120 cc or so), but I'd rather overrun on the first flight than quit in the overheads.

Chris
Title: Re: Tank size for St60
Post by: Vincent Corwell on June 26, 2007, 06:30:21 AM
Hi Chris
I am using a 6 oz plastic clunk
First flights needed 5 ounces
after some more flying this is
reducing by 1/2 oz or so
4 oz too small to start with
why not use full 6 oz on early
trimming flights and use less
as the motor breaks in fully?
See you

Vincent
Title: Re: Tank size for St60
Post by: steven yampolsky on June 26, 2007, 11:13:16 AM
Fuel usage depends on venturi diameter and head clearance. If you are using .320 venturi with Big Jim style hemi head, expect to use 8oz. That's an extreme, of course but I've never seen a ST60 running on 4oz of fuel. 6oz for 6:30 run time is more typical.
Title: Re: Tank size for St60
Post by: Bill Little on June 27, 2007, 01:48:55 PM
I was talking with Windy about a month ago about what size tank to use.  I have a Large James Hemi, and the nose is a *little* cramped on a new plane underconstuction.  He told me the he used 5 1/2 oz. to 6 oz. in his planes when he was flying the BJM set ups at the NATS.  I will put a 6 oz. tank in mine to start with. ;D  5% nitro all the way.............
Title: Re: Tank size for St60
Post by: Chris Gilbert IRL-1638 on June 28, 2007, 06:27:40 AM
Thanks guys. I just needed a ball park figure to start with before I start soldering.
Title: Re: Tank size for St60
Post by: RandySmith on June 28, 2007, 09:36:23 AM
Hi Guys,

I need a ball park capacity figure for a tank for an ST60.

I expect to be running it on 25% castor and 5% nitro or so, and I need it to run for around 7 mins (F2B).

I'm guessing 4 oz (120 cc or so), but I'd rather overrun on the first flight than quit in the overheads.

Chris

HI Chris

The majority of the ones I have seen and flown  used 6 ounces for a pattern. Unless you run them very very rich or use very high nitro , or  someone have reworked the baffle on top of the piston, 6 ounces will normally work fine

Randy