Horse power....

6

6cuda6

Active member
Jul 1, 2019
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59
Ontario, Canada
Ok so there is "no replacement for displacement" but i know we are limited. So far it looks like one can move to a Cad 500, twin turbo a la JimK.....
has anyone tried a ProCharger? (Belt driven super charger)

The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the next couple years and has expressed vocally that the coach is a "sled" on
the hills....lol.
--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
Change the final drive gearing, sail over the hills, and spend the money
you would have spent on the supercharger to buy us all a round or two next
time we meet.
Jim Hupy
Salem, Oregon

On Tue, Oct 1, 2019, 7:24 AM tonka6cuda6--- via Gmclist <

> Ok so there is "no replacement for displacement" but i know we are
> limited. So far it looks like one can move to a Cad 500, twin turbo a la
> JimK.....
> has anyone tried a ProCharger? (Belt driven super charger)
>
> The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the
> next couple years and has expressed vocally that the coach is a "sled" on
> the hills....lol.
> --
> Rich Mondor,
>
> Brockville, ON
>
> 77 Hughes 2600
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
What is the recommended gearing Jim? And id be happy to buy you folks a round or 2 of Canadian beers....lol.

> Change the final drive gearing, sail over the hills, and spend the money
> you would have spent on the supercharger to buy us all a round or two next
> time we meet.
> Jim Hupy
> Salem, Oregon
>
> On Tue, Oct 1, 2019, 7:24 AM tonka6cuda6--- via Gmclist <

>
> > Ok so there is "no replacement for displacement" but i know we are
> > limited. So far it looks like one can move to a Cad 500, twin turbo a la
> > JimK.....
> > has anyone tried a ProCharger? (Belt driven super charger)
> >
> > The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the
> > next couple years and has expressed vocally that the coach is a "sled" on
> > the hills....lol.
> > --
> > Rich Mondor,
> >
> > Brockville, ON
> >
> > 77 Hughes 2600
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
Tonka6:
I am not a mechanic or expert, but I have heard many an expert recommend the 3:70 final drive upgrade as opposed to the 3:55 or 4:10s that are also available.
My buddy Bob Dunahugh tows a 17,000 # race car & trailer behind his 3:70 final drive GMC without a problem - has for years and lots of cross country miles.
When I do my 28’ stretch, I am going w/ the 3:70 final drive from Jim Kanomata.
Just my humble opinion!
Mike/The Corvair a holic

Sent from my iPhone

>
> What is the recommended gearing Jim? And id be happy to buy you folks a round or 2 of Canadian beers....lol.
>

>> Change the final drive gearing, sail over the hills, and spend the money
>> you would have spent on the supercharger to buy us all a round or two next
>> time we meet.
>> Jim Hupy
>> Salem, Oregon
>>
>> On Tue, Oct 1, 2019, 7:24 AM tonka6cuda6--- via Gmclist <

>>
>>> Ok so there is "no replacement for displacement" but i know we are
>>> limited. So far it looks like one can move to a Cad 500, twin turbo a la
>>> JimK.....
>>> has anyone tried a ProCharger? (Belt driven super charger)
>>>
>>> The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the
>>> next couple years and has expressed vocally that the coach is a "sled" on
>>> the hills....lol.
>>> --
>>> Rich Mondor,
>>>
>>> Brockville, ON
>>>
>>> 77 Hughes 2600
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> Rich Mondor,
>
> Brockville, ON
>
> 77 Hughes 2600
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Ok thats sounds realistic. I have 4:11 in my car and they are not the best on the highway....lol.

> Tonka6:
> I am not a mechanic or expert, but I have heard many an expert recommend the 3:70 final drive upgrade as opposed to the 3:55 or 4:10s that are
> also available.
> My buddy Bob Dunahugh tows a 17,000 # race car & trailer behind his 3:70 final drive GMC without a problem - has for years and lots of cross
> country miles.
> When I do my 28' stretch, I am going w/ the 3:70 final drive from Jim Kanomata.
> Just my humble opinion!
> Mike/The Corvair a holic
>
> Sent from my iPhone
>

> >
> > What is the recommended gearing Jim? And id be happy to buy you folks a round or 2 of Canadian beers....lol.
> >

> >> Change the final drive gearing, sail over the hills, and spend the money
> >> you would have spent on the supercharger to buy us all a round or two next
> >> time we meet.
> >> Jim Hupy
> >> Salem, Oregon
> >>

> >>
> >>> Ok so there is "no replacement for displacement" but i know we are
> >>> limited. So far it looks like one can move to a Cad 500, twin turbo a la
> >>> JimK.....
> >>> has anyone tried a ProCharger? (Belt driven super charger)
> >>>
> >>> The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the
> >>> next couple years and has expressed vocally that the coach is a "sled" on
> >>> the hills....lol.
> >>> --
> >>> Rich Mondor,
> >>>
> >>> Brockville, ON
> >>>
> >>> 77 Hughes 2600
> >>>
> >>> _______________________________________________
> >>> GMCnet mailing list
> >>> Unsubscribe or Change List Options:
> >>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>>
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> >
> > --
> > Rich Mondor,
> >
> > Brockville, ON
> >
> > 77 Hughes 2600
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
3.70 is pretty awesome. UNLESS you like to drive >70 on the freeway.
Me I like to take the 2 lane roads and with 3.70 it is a lot happier on the rolling hills.
And yeah, if you step on it, it will go
________________________________
From: Gmclist on behalf of tonka6cuda6--- via Gmclist
Sent: Tuesday, October 1, 2019 10:19 AM
To: gmclist
Cc: tonka6cuda6
Subject: Re: [GMCnet] Horse power....

Ok thats sounds realistic. I have 4:11 in my car and they are not the best on the highway....lol.

> Tonka6:
> I am not a mechanic or expert, but I have heard many an expert recommend the 3:70 final drive upgrade as opposed to the 3:55 or 4:10s that are
> also available.
> My buddy Bob Dunahugh tows a 17,000 # race car & trailer behind his 3:70 final drive GMC without a problem - has for years and lots of cross
> country miles.
> When I do my 28' stretch, I am going w/ the 3:70 final drive from Jim Kanomata.
> Just my humble opinion!
> Mike/The Corvair a holic
>
> Sent from my iPhone
>

> >
> > What is the recommended gearing Jim? And id be happy to buy you folks a round or 2 of Canadian beers....lol.
> >

> >> Change the final drive gearing, sail over the hills, and spend the money
> >> you would have spent on the supercharger to buy us all a round or two next
> >> time we meet.
> >> Jim Hupy
> >> Salem, Oregon
> >>

> >>
> >>> Ok so there is "no replacement for displacement" but i know we are
> >>> limited. So far it looks like one can move to a Cad 500, twin turbo a la
> >>> JimK.....
> >>> has anyone tried a ProCharger? (Belt driven super charger)
> >>>
> >>> The wife wants to tackle the Rockie Mounts and the Smokey Mountain in the
> >>> next couple years and has expressed vocally that the coach is a "sled" on
> >>> the hills....lol.
> >>> --
> >>> Rich Mondor,
> >>>
> >>> Brockville, ON
> >>>
> >>> 77 Hughes 2600
> >>>
> >>> _______________________________________________
> >>> GMCnet mailing list
> >>> Unsubscribe or Change List Options:
> >>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>>
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> >
> > --
> > Rich Mondor,
> >
> > Brockville, ON
> >
> > 77 Hughes 2600
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Rich Mondor,

Brockville, ON

77 Hughes 2600

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Can you just change the gears and chain instead of the final drive? Just seems much easier in theory.....havent actually looked at it.
--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
The gearing discussions kinda center around coach size, 23 vs 26, and
towing heavy vs not towing, and finally, 403 vs 455.
It goes something like this:
If you tow heavy, or have a 403 engine in a 26 foot coach, then the 3:70 or
even the 4:10 is what you want.
If you have a light 26 ft or a 23 ft and you do not tow, then a 3:55 will
suffice with a 455.
But, this is not chiseled in stone. And still subject to discussion.
Personally, I have a late 1978 Royale that has a 403, and I sometimes
tow a trailer. So, I have a 3:70 in my coach with Doug Thorley Ceramic
coated headers, a recurved HEI ignition, properly adjusted for the headers
and recurved ignition Quadrajet. It will pull the grapevine coming out of
LA without downshifting.
Coming Northbound over the Siskiyou's on interstate 5, there is one long
uphill that I shift into 2nd for, the other small passes like Wolf Creek I
pull in top gear. So, I can easily run 75 mph anytime I choose. The 403
loves the higher rpms. Never over 3600 rpms except when I downshift.
Jim Hupy
Salem, Oregon

On Tue, Oct 1, 2019, 8:20 AM tonka6cuda6--- via Gmclist <

> Ok thats sounds realistic. I have 4:11 in my car and they are not the best
> on the highway....lol.
>

> > Tonka6:
> > I am not a mechanic or expert, but I have heard many an expert recommend
> the 3:70 final drive upgrade as opposed to the 3:55 or 4:10s that are
> > also available.
> > My buddy Bob Dunahugh tows a 17,000 # race car & trailer behind his 3:70
> final drive GMC without a problem - has for years and lots of cross
> > country miles.
> > When I do my 28' stretch, I am going w/ the 3:70 final drive from Jim
> Kanomata.
> > Just my humble opinion!
> > Mike/The Corvair a holic
> >
> > Sent from my iPhone
> >

> > >
> > > What is the recommended gearing Jim? And id be happy to buy you folks
> a round or 2 of Canadian beers....lol.
> > >

> > >> Change the final drive gearing, sail over the hills, and spend the
> money
> > >> you would have spent on the supercharger to buy us all a round or
> two next
> > >> time we meet.
> > >> Jim Hupy
> > >> Salem, Oregon
> > >>
> > >> On Tue, Oct 1, 2019, 7:24 AM tonka6cuda6--- via Gmclist >

> > >>
> > >>> Ok so there is "no replacement for displacement" but i know we are
> > >>> limited. So far it looks like one can move to a Cad 500, twin turbo
> a la
> > >>> JimK.....
> > >>> has anyone tried a ProCharger? (Belt driven super charger)
> > >>>
> > >>> The wife wants to tackle the Rockie Mounts and the Smokey Mountain
> in the
> > >>> next couple years and has expressed vocally that the coach is a
> "sled" on
> > >>> the hills....lol.
> > >>> --
> > >>> Rich Mondor,
> > >>>
> > >>> Brockville, ON
> > >>>
> > >>> 77 Hughes 2600
> > >>>
> > >>> _______________________________________________
> > >>> GMCnet mailing list
> > >>> Unsubscribe or Change List Options:
> > >>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> > >>>
> > >> _______________________________________________
> > >> GMCnet mailing list
> > >> Unsubscribe or Change List Options:
> > >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> > >
> > >
> > > --
> > > Rich Mondor,
> > >
> > > Brockville, ON
> > >
> > > 77 Hughes 2600
> > >
> > > _______________________________________________
> > > GMCnet mailing list
> > > Unsubscribe or Change List Options:
> > > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> Rich Mondor,
>
> Brockville, ON
>
> 77 Hughes 2600
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ok....i have a 26' with a 403....i dont plan on towing a trailer at this point in time. So i think the smart choice here will be 3:70 as it seems to
an all around ratio.

Future ..will add headers and probably EFI but gotta get the thing safety inspected first which means at least one windshield....got the exhaust leak
fixed so hopefully ill try a glass repair and see if thats good enough.
--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
This is kind of off-topic.
I think that if you fix the problem by putting more HP into the system puts
more stress on the transmission and FD. Does going to a lower FD ratio
increase FD transmission reliability?

On Tue, Oct 1, 2019 at 9:37 AM tonka6cuda6--- via Gmclist <

> Ok....i have a 26' with a 403....i dont plan on towing a trailer at this
> point in time. So i think the smart choice here will be 3:70 as it seems to
> an all around ratio.
>
> Future ..will add headers and probably EFI but gotta get the thing safety
> inspected first which means at least one windshield....got the exhaust leak
> fixed so hopefully ill try a glass repair and see if thats good enough.
> --
> Rich Mondor,
>
> Brockville, ON
>
> 77 Hughes 2600
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--

*John Phillips*
 
I made similar modifications as Jim Hupy to my 455. That would be my suggestion especially if you travel in mountain country in flat lands maybe the
3:55 would suffice. Actually the lower gears may yield better fuel mileage as you don't lug the motor as much.
--
Roy Keen
Minden,NV
76 X Glenbrook
 
As for gearing, I find that the 3.42 gears that my beloved PO installed are perfect for my 26' Royale (heavy) coach, with its mighty 403. Living in
the west, those gears seem to be right at home at any reasonable cruising speed from 60 to 75mph, and from what I can tell don't have a real negative
impact on gas mileage (not sure that would be the case with a much higher numerical gear set). If I was going to tow anything heavy, I'd opt for a
set of 3.70 or similar, no doubt.

The only problems I ever ran into was above 6,000' of altitude (which happens a lot with Flagstaff being just "up the hill" from Mesa, at 7,500' with
lots of 6-7° hills to climb). The carb was fine below that level, but any time I was going up a hill above about 6,000' the motor just ran out of
steam and I'd be mashing my right foot into the carpet, downshifting sometimes to first to generate enough power.

Fast-forward to my last trip to the Grand Canyon, after installing the FiTech fuel injection system. Now it just cruises up the hills - not really
much difference at altitude compared to sea level, which makes it a LOT easier to drive. Sure, I still downshift on the steeper climbs, but can go up
at partial throttle and it sure seems that I'm burning a LOT less gas in the process.

I can't say that the fuel injection system really increases power at sea level, but it sure starts easier and passes emissions with ease (so did my
carb though).
--
Mark Hickey
Mesa, AZ
1978 Royale Center Kitchen
 
Once I got the cooling straightened out, my 23' with stock (3.07) gears pulled Cowee Mountain S of Sylva NC both ways with the toad on back without a
problem. Walked over Monteagle, 45 per in S. My 26' has 3.7 gears and with the toad on back and the Jasper motor would spin the wheels on takeoff
although that motor had a lot of cam it didn't need and consequently really chitty mileage until it broke the cranklshaft.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Those that know me know that I was an engine professional in OE land for many years. I also did other things....

Last year I had to "refresh" my engine. I put in the cam by number that Dick Paterson recommended. It is much better than it was, but it is still
cruising below the torque peak at 60 MPH. That is undesirable. It is still actually more comfortable with 70MPH, but both I and fuel rate are less
comfortable. If I had the loose change, I would go to a 3.55 in a heartbeat. But again, this is with a different cam and a VERY LIGHT (9460#) coach.


If I had any 26' anything, I would put a 3.70 in it at the earliest convenience.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
If there is someone out there in the rare situation that they have a 3.7,
but wish they had a 3.5... I have a 3.5 that i have not yet installed into
my 26'. I would swap if it helps. 3.5, 3.7... both are better than the
3.07! Its a win for me no matter which one goes in.

-Will

On Tue, Oct 1, 2019 at 3:59 PM Matt Colie via Gmclist <

> Those that know me know that I was an engine professional in OE land for
> many years. I also did other things....
>
> Last year I had to "refresh" my engine. I put in the cam by number that
> Dick Paterson recommended. It is much better than it was, but it is still
> cruising below the torque peak at 60 MPH. That is undesirable. It is
> still actually more comfortable with 70MPH, but both I and fuel rate are
> less
> comfortable. If I had the loose change, I would go to a 3.55 in a
> heartbeat. But again, this is with a different cam and a VERY LIGHT
> (9460#) coach.
>
>
> If I had any 26' anything, I would put a 3.70 in it at the earliest
> convenience.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Don't use 4.10 in a muscle car with shorter 14-15" wheels and 60 series tires for comparison. We have usually 16" with 75 series tires.
Also the chain sprocket swap multiplies torque before the transmission clutches and hard parts. The final drive swap lightens the torque load on the
trans.
I'm happy with my USA 3.42 gears overall. Above 6% grade the 3.70 would be better but then not as good at 70 and above.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
If "it's a sled" on the hills something is wrong. Even with 3.07 you can just grab S or L though sooner than with higher number final. Throttle cable
not pulling fulling is almost a given. Stuck advance if never serviced is another given. Secondary lockout stuck due to gum or choke malfunction also
a possibility
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Boosted induction is a good way to make (restore) power at altitude. You have to be careful with heat though. Boost in cars is usually used for short
blasts, passing, merging etc. A long grade for 15 mins is a different story. You need a systems approach not just an add-on.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
I guess thats not a fair statement as the purchase trip home from out East the kick down didnt work and i never downshifted it manually....i guess i
could have and gained a few RPM. I still need to check the carb but SWMBO wants yo drive this as well and manual downshifting isnt going to
fly....trust me.

> If "it's a sled" on the hills something is wrong. Even with 3.07 you can just grab S or L though sooner than with higher number final. Throttle
> cable not pulling fulling is almost a given. Stuck advance if never serviced is another given. Secondary lockout stuck due to gum or choke
> malfunction also a possibility

--
Rich Mondor,

Brockville, ON

77 Hughes 2600
 
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