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3:27 or 3:55 for PG 110
Posted by: Ron62 ()
Date: January 08, 2019 03:23PM

Whats the better setup for daily driver. I have a 67 110 PG and while apart re-sealing the engine, thought this might be a good time to investigate opinions on the gearing.

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Re: 3:27 or 3:55 for PG 110
Posted by: American Mel ()
Date: January 08, 2019 03:29PM

I would think it has a LOT to do with what type of driving you do.
My PG car seems to be turning higher revs than I would really like when I am keeping up with traffic on the freeway.
So, my thoughts would be . . .
3:27 if you do a lot of freeway driving
3:55 around town.
I am sure that there are those with 3:27 experience that will jump in though.

.
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WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater
'67 A/C Moredoor Monza - 140 4-spd. driver



Edited 1 time(s). Last edit at 01/08/2019 03:31PM by American Mel.

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Re: 3:27 or 3:55 for PG 110
Posted by: Vairismo ()
Date: January 08, 2019 03:30PM

Depends on the daily driving. If long stretches of highway like commuting then the 3.27. If a lot of stop and go around town then probably the 3.55. My opinion of course.

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Re: 3:27 or 3:55 for PG 110
Posted by: Ron62 ()
Date: January 08, 2019 03:39PM

Well im thinking mostly around town and then off the events and shows utilizing the highways. So combined driving I guess.

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Re: 3:27 or 3:55 for PG 110
Posted by: American Mel ()
Date: January 08, 2019 03:42PM

Events?
Shows? - does not matter.
Autocrossing? - 3:55
Econruns? - 3:27

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater
'67 A/C Moredoor Monza - 140 4-spd. driver

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Re: 3:27 or 3:55 for PG 110
Posted by: Timothy Shortle ()
Date: January 08, 2019 04:04PM

Most LM PG diffs are 3.55. 3.27 might be a little tough to locate (if you are wanting to buy gears already attached to the carrier and the pinion shaft).

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Re: 3:27 or 3:55 for PG 110
Posted by: fred bagnall ()
Date: January 08, 2019 06:19PM

My 67 that I sold to Jerry Murray (ac 1948) had a 95hp with 3:27 gearing . That car was great on the highway and had plenty of pickup. My Greenbrier had 3:55s when I purchased it . I have driven it cross county 3 times in the last 2 years . I swapped out the 3:55s for a 3:27 and drove it back to Florida and then to Washington state. It is a little slower on take off,but I did get an almost 4 gallon improvement on the highway mileage .thumbs upthumbs up


64 Greenbrier std -110, 4spd,barn find on the road again after 46 year hiatus.
66 Turbo Corsa, 180hp,posi-trac, quick steering HD suspension,AM-FM-multiplex,soft-Ray glass all around
Floridian currently residing in Nor Cal

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Re: 3:27 or 3:55 for PG 110
Posted by: 66vairman ()
Date: January 08, 2019 07:01PM

For a lot of highway driving the 3:27 is nice, BUT it won't give you low highway RPM like a modern over/direct drive train. So don't expect more than about a 300RPM drop at 70MPH. Corvair engines were not designed to cruise at low RPM like today's modern engines.

A 3:55 PG 110HP can run all day long at 70MPH (providing you have the correct size tires) with no ill effects. It also has slightly more pep off the line vs. the 3:27.

The PG has a torque converter that will mask some of the difference between a 3:55 and 3:27. Just my experience, but the difference between the 3:55 and 3:27 is more noticeable with a manual transmission.

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Re: 3:27 or 3:55 for PG 110
Posted by: v8vair ()
Date: January 08, 2019 08:02PM

3:27 for all my street cars, PG or manual. the car just doesnt feel as busy and lets the gears wind out a little further between shifts. More relaxed to me, Mike

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Re: 3:27 or 3:55 for PG 110
Posted by: TerribleTed ()
Date: January 08, 2019 10:37PM

I have had both. I prefer the 3:27 with a powerglide. Not much difference at lower speeds and less noise and better pickup at highway speeds.

---------------------------------------------------------------------------------------------------------

Avid Corvair hobbiest since 1984.
I have personally performed ground up restoration on over 20 Corvairs.
I currently work full time at restoring and repairing Corvairs.
Located in the Atlanta Georgia area.
[www.facebook.com]

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Re: 3:27 or 3:55 for PG 110
Posted by: Ron62 ()
Date: January 09, 2019 04:15AM

So after finding the stamping on my diff last night, it appears that I have a 3:55 . So Ill be staying with that. Does any have a recommendation on Tire size that will run good with this setup? Im wanting to upgrade to 15 or 17 inch wheels.

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Re: 3:27 or 3:55 for PG 110
Posted by: 67 airvair ()
Date: January 09, 2019 04:22AM

Guys, you'er not helping (me, at least). confused smiley I went through this same thing with my project car's drive train just last year. First with a 3.55, then a 3.27, then back to a 3.55, all at great expense each time, and STILL zero miles on it. angry smiley

I've come to the conclusion that it's just going to have to be a guessing game until I DO get it on the highway, confused smiley then I'm either going to love it and congratulate myself for lucking out (a first in my life!),eye popping smiley and then wonder what it would have been like with the other ratio in it. eye rolling smiley Or I'm going to wish I had the other ratio in it, and will have to decide if I want to go to all the time, money, and aggravation to change it, only to possibly regret THAT decision as well. angry smiley

Story of my life...sad smiley

-Mark

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Re: 3:27 or 3:55 for PG 110
Posted by: Ron62 ()
Date: January 09, 2019 07:00AM

For me its a guessing game as well. Where I plan on using it mostly as a daily driver in good weather and limited highway use except for short trips to events or show etc, I think the 3:55 should be good. I also live in a farily hilly area in New England and feel the 3:55 will be better on the hills. Time will tell.

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Re: 3:27 or 3:55 for PG 110
Posted by: Timothy Shortle ()
Date: January 09, 2019 07:41AM

For sure 3.55s will be better in the hills.

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Re: 3:27 or 3:55 for PG 110
Posted by: viewmaster ()
Date: January 09, 2019 07:51AM

My experience: Daily driver, foothills to freeways and back, with a 3:55. Good for my commute, but fuel economy suffers a bit when keeping up with traffic. I would imagine a 3:27 being too tall for the foothills.

-m



Mike
'65 '500' Sedan 110 PG
'65 Monza Sedan turbo'd 110 SU conversion
Fresno, CA

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Re: 3:27 or 3:55 for PG 110
Posted by: nnsquared ()
Date: January 12, 2019 08:06AM

You can make small increment changes with tire diameters, and wheel diameters. Lots of variables, and wheel/tire cost for trials.
I found 355 to be high rpm on freeway, but no problem slow local speeds.

Regards,
Kerwin,
Valley Forge, PA
65 Monza 110 PG, Stinger wannabe SW 001


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Re: 3:27 or 3:55 for PG 110
Posted by: Brizo ()
Date: January 12, 2019 09:51AM

No doubt, the 3:55 ratio is best "all around" with a PG trans. Yes,the RPM is high on the highway compared to your new cars, but it wont hurt a good engine. Forty years ago nobody gave cruising RPM a second thought because OD and lock-up AT's didn't exist and most all the cars turned that fast. Until someone finds a multi-speed AT transaxle that can be adapted to the Corvair engine without an insane amount of investment in R&D and custom parts, we're stuck with what we have.

Dan Brizendine,
'64 8door Greenbrier 140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

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Re: 3:27 or 3:55 for PG 110
Posted by: 67 airvair ()
Date: January 12, 2019 11:52AM

Now if only we could find that one tranny from "Pinky". The trans-axle was a GM experimental turbo-hydro three speed, with a park in it. Last seen somewhere in Michigan in a derelict old '60 GM show car, made from a '60 coupe and cut down to a convertible. The car was painted pink in and out for a GM exec'x wife, and spent years being run in the salt of Michigan.

-Mark

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Re: 3:27 or 3:55 for PG 110
Posted by: MattNall ()
Date: January 12, 2019 12:40PM

And finally scrapped by the "Unaware" owner....





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: 3:27 or 3:55 for PG 110
Posted by: john.jackson ()
Date: January 12, 2019 01:04PM

Ron62 Wrote:
-------------------------------------------------------
> For me its a guessing game as well. Where I plan
> on using it mostly as a daily driver in good
> weather and limited highway use except for short
> trips to events or show etc, I think the 3:55
> should be good. I also live in a farily hilly
> area in New England and feel the 3:55 will be
> better on the hills. Time will tell.

Ron,

I would stick with the 3.55 you have and experiment with different size tires and wheels for two reasons: First, tires are a running expense anyway. Second, it is easier and less expensive to change the tire size than to change the final drive.

The OEM tixre size for 67 took 830 revolutions per mile. On my 67 I use 195/65 x 15 tires - an exact match. But I can try out 215/70 x 15 and several other sizes for not too much money.

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