VGs and 8.00-6 vs 8.50-6

How to keep the Cessna 170 flying and airworthy.

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Grizzley
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Joined: Fri Apr 13, 2018 10:30 pm

VGs and 8.00-6 vs 8.50-6

Post by Grizzley »

I have read through many posts regarding VGs and larger tires.
I have a 1953 170B with 180 gear and P-Ponk, Horton STOL kit and Flint auxiliary fuel tanks (makes the wingspan 38'), it also has an 80" X 43 prop.
I hangar at an airport with asphalt runway. I do however like to go to short out of the way airfields or off airport. Being in Eastern Ontario, we are at 175' ASL but with mountains nearby, that is where we end up flying.
I would like to go to a larger tire, not bush wheels because I would not have need where I will be flying. I now have 6.00-6 and would like to go to 8.00-6 or 8.50-6 if aproved on the 170's.
I also want to install VGs and would like to know the best VGs aproved for the 170B w/Horton.
Thank you for any information or help.
JD
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wabuchanan
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Re: VGs and 8.00-6 vs 8.50-6

Post by wabuchanan »

I bought my plane with 6.00 x 6's, then went to 8.00 x 6's, then.....went to 8.50 x 6's with the Dodge Letter for approval. My opinion is if you are landing on pavement a lot with the occasional grass strip and/or Off Airport, the 8.50's with tread work very well indeed and are about the perfect size for the 170. I too have the P-Ponk and an 80 x 42 prop and go to short mountain strips.

Others will tell you the 8.00' x 6's will do you just as well and I would be hard put to argue the point, other than the 8.50's seem to absorb the bumps better.

(I am looking at STC's and/or Field approvals for 26's now, because I am immature at heart and "know" that if big is good.....Bigger is "always" better....!) :mrgreen:
1950 170A N5776C SN:19730
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Bruce Fenstermacher
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Re: VGs and 8.00-6 vs 8.50-6

Post by Bruce Fenstermacher »

I believe there is only one VG STC from Micro AeroDynamics.

https://microaero.com/
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Bruce Fenstermacher, Past President, TIC170A
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Grizzley
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Re: VGs and 8.00-6 vs 8.50-6

Post by Grizzley »

Thank you for the replies
JD
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Bruce Fenstermacher
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Re: VGs and 8.00-6 vs 8.50-6

Post by Bruce Fenstermacher »

8:00x6 are approved under the TCDS. 8:50x6 are not directly approved but many have been installed under various methods such as a approved 337 and using this FAA letter of understanding to simply installing them and asking forgiveness if guestioned.

So as far as the approval process 8:00x6 is fairly cut and dry, 8:50x6 is a little fuzzy.

You will have to decide if the larger tires are worth the price and additional hassle.

I've only used 8:00x6 and really only cause I like the look more than needing them. Currently I'm running 7:00x6 and they work as well as the 8:00 on the soft grass I operate yet have slightly less cost in drag and $$$$$.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
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Grizzley
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Joined: Fri Apr 13, 2018 10:30 pm

Re: VGs and 8.00-6 vs 8.50-6

Post by Grizzley »

Onemore question on 8.50 vs 8.00 (both 6 ply)
I presently have 6" Cleveland wheels and brakes, do I need different wheels or adapter to go to 8.50 and do I have to get double pucks instead of single puck I have now?
How about tubless tires/wheels, if I could "seal" my current wheels, I would not only save $$$ on tubes, but if needed I could run less pressure and avoid tire creeping on the rim.

Thanks,
JD
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wabuchanan
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Re: VGs and 8.00-6 vs 8.50-6

Post by wabuchanan »

Grizzley wrote:Onemore question on 8.50 vs 8.00 (both 6 ply)
I presently have 6" Cleveland wheels and brakes, do I need different wheels or adapter to go to 8.50 and do I have to get double pucks instead of single puck I have now?
How about tubless tires/wheels, if I could "seal" my current wheels, I would not only save $$$ on tubes, but if needed I could run less pressure and avoid tire creeping on the rim.

Thanks,
JD
Your 6" Cleveland wheels and brakes will work fine on 8.50's. You will notice some decreased braking efficiency, or put another way, you will need increased effort in braking. But they still work fine.
If you utilize the treaded 8.50's there should be no clearance issues. If you use the non treaded Desser mini tundra 8.50's you may have to do some minor clearance with the brakes.

If you decide to go with 26" Goodyears, your 6" Cleveland wheels will work, and single puck brakes will work marginally, but you will have to do significant clearance work with spacers/washers and some caliper clearance. But they will work. There currently is no approval basis for this combination other than a field approval.

If you go to the 26" Alaskan Bushwheel STC, they require double puck brakes, but the 6" Cleveland wheels will still work. Their tires are molded to clear the brakes and are of an integrated tubeless design that does not need sealing of your wheels. The only tubeless tires that I personally know of are the proprietary ABW Tundra tires of 26" and larger sizes.

Others on here may be able to tell you about tubeless tires within the normal size range for our 170's.
1950 170A N5776C SN:19730
Grizzley
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Re: VGs and 8.00-6 vs 8.50-6

Post by Grizzley »

Thank you
I will check with my AME/AMO if the Atlee Dodge letter and having 180 gear will suffice for Transport Canada.
JD
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