80mm front caliper conversion question

scott nutter1

New member
Jan 5, 2015
729
0
0
Hi Sandy,
Sounds like you have a center kitchen royal. That's a good one. Finished off by coachman.
Treat her right! Any vin or tze number? Sometimes on the code sheet on the inside of the glove box lid. Should have a date stamp on it also.
Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
installed MSD Atomic EFI
Houston, Texas
 
Sandy(?),

Welcome to the group, family, cult, asylum.

One of the first things I am going to do is to suggest that you fill in a sigfile. Go to and scroll down. Put in a
real name, we like those here because you will meet other owners and they won't know you from a wet fish, but you will already be friends. A bit
about the coach should also be included. In your case, this sounds like a '78 side bath Royale (Coachmen). That tells us a lot. Include any
significant mods in the case this changes things. A geographic reference is good to because you may already have a close by brand new old friend that
can be of some assistance to you. (Then
you have to scroll down to .)

Do not fret about the GVW of brake lines. That reference is for what trucks it goes on. All hydraulic brake lines are tested to the same DOT
specifications for approval. As to changing the rear to disk brakes, I suggest that you hold off until Applied (aka JImK) gets the testing he wants
to do done. There are lots of people running different arrangements, and some interesting things are turning up. I would also suggest that you get
to an International and talk to Dave Lenzi before you roll into any investment for changes.

Finding your way here was a real good thing too. This is a supportive and helping community that you have probably never experienced before (that is
part of the reason for the full sigfile). We are all interested to see that you get to enjoy your coach and what it can do for you as much as we know
it can and will.

As said, this is a community like few others and the only other that I know is that of the watermen that are my world, for that reason I have taken to
welcoming new owners there much as any new owner or vessel is welcomed there. So,

May the Good Lord bless this coach and all those that set forth within her.

Welcome Sandy(?)

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
 
Dave is not on this forum, Emails work but he is a super busy guy so it may take a day or so to reply.

http://www.bdub.net/lenzi/

Thats a partial offering, I know he has middle wheel disk conversion kits as well as several other parts.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
HT 3s in D load range are iffy - the Royale is a heavy coach. I r5un HT3s in E load range, the cost difference isn't great. When you go to a GMCMI
rally, weigh your coach. You're borderline on Ds.

--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" - ol Andy, paraphrased
 
The cost different between a D and E rated tire is not worth skimping. You can see the weight on the name plate, but believe me you running a lot heavier. Our coach is a Buskirk Chassis #5 weights about 12,400# empty. Loaded up with fuel 75 gal., no water until we get out of the freezing areas and all the needed stuff to spend the winter in Tucson the coach is at 14,600# (weighted at a GMCMI Convention) and we tow a car that we use as a trailer so add another 3800# going down the road.

JR Wright
Michigan
Buskirk Stretch

>
> HT 3s in D load range are iffy - the Royale is a heavy coach. I r5un HT3s in E load range, the cost difference isn't great. When you go to a GMCMI
> rally, weigh your coach. You're borderline on Ds.
>
> --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" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
E-rated fires were cheaper and more available that D-rates tires last time
I bought them. Either work on my 9300-pound coach.

Rick “who never inflates above 65 psi anyway” Denney

> The cost different between a D and E rated tire is not worth skimping.

--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
 
Sandy,
In answer to your original question, get the 80mm (3 5/32") calipers. Use with quality semi-metallic or equivalent pads. You'll have to change out
the front brake hoses (AutoZone part numbers have been posted on vario0us sites, don't have' 'em handy right now). This was the first of several
upgrades I made to my brakes and one of the most cost-effective. Next I'd suggest a "sensitized" booster from Jim B or JimK, and a reserve vacuum
pump. My .02.

HTH
Rick Staples
--
Rick Staples, '75 Eleganza, Johnstown, CO

"Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
 
Amen John W.:
Thanks for making the weight issue very clear for all GMCers!!!
Mike/The Corvair a holic

Sent from my iPhone

>
> E-rated fires were cheaper and more available that D-rates tires last time
> I bought them. Either work on my 9300-pound coach.
>
> Rick “who never inflates above 65 psi anyway” Denney
>

>>
>> The cost different between a D and E rated tire is not worth skimping.
>
> --
> Rick Denney
> 73 x-Glacier 230 "Jaws"
> Off-list email to rick at rickdenney dot com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Thanks for all the great info.
> I looked at Dave Lenzi's web site and he has a lot of interesting upgrades.
> Who is the expert on the brake options?

Sandy,

In truth, no body is....
JimK and Tom P have done some engineering lever testing, but the rest is based on peoples impressions and anecdotal reports.
Jim and Tom can show you data that they can improve the stock brake configuration by 0.1G. (That is a big number in retarding/braking.) I have the
original brakes, but with floating backplates (if you are/were a dirt biker) here referred to as reaction arms. The difference they make in the rear
brake is very impressive.

We do have a simple to do with Dave, if you need or want it and Dave is selling, don't ask questions. That is what you want.

When we first got this coach, the dragging rear tires bothered me and I did a set of analysis of the situation and that told me that there was no easy
fix. This bugged me because I did work two years in foundation brakes for a Detroit OE. I am trying to locate that study in the hopes it will be of
value for a set of new tests that are expected to be run pretty soon now. I have hope, but it got a little dimmer today when I found that the archive
drive for that period (about 10 years ago) is not cooperating.

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
 
> I double checked the Cooper tires, they are HT3 M&S with a load range of E. They are as quiet as the Michelins, but with less than half the price
> and handle very well.
> Thanks Rick for the info about the caliper piston size and the pad selection.
> Thanks Matt for the brake info, what does the dragging rear tires refer to?

Sandy,

If you have an unmodified coach and do a panic stop on dry pavement, the way rear wheels will probably lock. If you stay on the for any time at all,
you will make flat spots on those tires. There are several attacks for this of varying success. I believe the "Reaction Arm" version of floating
back plates is the best as then all 4 rear brakes get to work equally.

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
 
Well you chose good tires. I ran Michelin LTX for 12 years no incidents no checking mostly climate controlled storage. Then bought Cooper HT3s 2
years ago. Both balanced out well and provide great ride. I rate the HT3 better on dry roads (sidewall seems slightly more supportive in truck wash)
and rate the LTX slightly better in M/S and wet. They have similar tread blocks but the outer rows are solid on the HT3 which may contribute to less
squirm but slightly poorer water evacuation and M/S grip. Made in USA. Time will tell.
--
John Lebetski
Woodstock, IL
77 Eleganza II