Gears Gears and Myths

[philip l. stewart]

Arch,
My 23' Transmode with 455 and Quadrajet and 90K miles at the the time "came
alive" for me when I changed from the 3.07 OEM final drive to the 3.42. I
noticed much improved acceleration and ability to climb the grades here in
East Tennessee and the Rockies too, while holding cruise control settings
more constant as well. There was no improvement noticed in mpg, but I was
running too rich before the swap to make any comparison useful. I really
like the improved engine breaking effect on downhills with the 3.42 . I
don't pull a toad (yet), but don't see how in my situation any lower gearing
would make me happier. The 3.42 has about 16,000 miles on it now and there
have been no mechanical problems with it. I installed it myself. That's
what I did.
Phil Stewart
'76 Transmode, TN

> GMCers
>
> I have a real need to reopen this discussion. Its my next project.
> I would like to see if we can discuss the final numbers and not how
> to get there.............
>
> Take Care
> Arch 76 GB IL

 

[homebase1]

GMCers
Before y'all go out and spend a fortune on gears, do the basics. I
took a night off this week and put in a carb kit. This was followed
by an adjustment at the top of the gas peddle !!! Flat part bent
forward to make the linkage snug so the 4 barrels come is as they
should and top curved part bent back to keep the kick-down switch
from coming in too soon. Talk about a difference, and all for the
price of a kit ($20.00)

Now I'm ready for the WV hills.........

Mikeb

 

[nate chase]

Mike,
So your linkage was misadjusted and the 4 barrel didn't kick in fast
enough? Is that it? I noticed my 4 barrel doesn't kick in much (seems doggy
at times) and the kick-down (which I replaced) takes a good 4-5 sec to kick
in on a hill. Don't need a carb kit as mine is all new but sure will look
closer at my linkage now... Thanks.

Nate '75GB (Trick 'r Treatin' on my H-D w/70 degrees today!) Omaha

>

Date: Sun, 31 Oct 1999 15:25:14 -0500
From: homebase
Subject: Re: GMC: Gears Gears and Myths

GMCers
Before y'all go out and spend a fortune on gears, do the basics. I
took a night off this week and put in a carb kit. This was followed
by an adjustment at the top of the gas peddle !!! Flat part bent
forward to make the linkage snug so the 4 barrels come is as they
should and top curved part bent back to keep the kick-down switch
from coming in too soon. Talk about a difference, and all for the
price of a kit ($20.00)

Now I'm ready for the WV hills.........

Mikeb

 

[homebase1]

Emery
You never cease to amaze me.........common sense ! But then do
I have to cancel the fishin' trip
Mike

>

Mike - anyone doing this can do the same thing by just putting a crimp on
lead fishing sinker between the pedal lever and the end of the cable.

Emery Stora
77 Kingsley
Santa Fe, NM

 

[hdavis]

>GMCers
>
>I have a real need to reopen this discussion. Its my next project.
>I would like to see if we can discuss the final numbers and not how
>to get there. We now have many options----more than ever before.
>The range is between 3.07 and a little over 4. This is very exciting
>to me. I even had a long conversation today with Jim Kanomata
>today about the 3.7. The other day I had a long conversation with
>Jim Bounds about Nate's coach. Jim said it really seem to come
>alive between 70 and 80 MPH.

My experience too.

Nate said much the same thing
>and I believe he even said he wished he had done the gears. So
>lets talk about the gears. Not who is right or wrong but just our
>thoughts. Maybe we should state the conditions under which we
>drive. How heavy is your Toad?

No Toad.

>How fast do you drive?

Speed limit +-. Az, NM, Utah, Tx, and other mid America states 75-80. Ca
and most interstates 65-70 (or with traffic)

>Are you a flatlander, hillbilly or mountain man?

All of the above. Ca central valley pretty flat, Donner pass is quite a
grade, Az NM is flat with parts of hills. Every summer I drive Ca to Pa and
back. Usually take the Northern route going and the middle route coming
back.

If you know---how
>heavy is your coach?

12,600 going cross coutry. Sometimes a few hundred heavier.

> What kind of modifications have been made
>to your coach? A cam--a shift kit---what?

None except 3" exhaust aft of teh muffler (in anticipation of maybe adding
headers).

Maybe we could begin to
>close in on this beast. I know I sure would like to. Can we just exchange
>thoughts and ideas---no right---no wrong? Lets try a new kind of group
>think-----maybe this one will be better. I would really like to see if
>we could move the GMCnet to the next level and come to some
>consensus on an issue. Yeah I know I am a dreamer.
>

Before I do anything like this I plan to monitor acceleration etc (maybe
find a dyno) to check the results.

Henry
>
Henry Davis Consulting, Inc / new product consulting
PO Box 1270 / product readiness reviews
Soquel, Ca 95073 / IP reviews
ph: (831) 462-5199 / full service marketing
fax: (831) 462-5198
http://www.henry-davis.com/ http://www.henry-davis.com