Home » Public Forums » GMCnet » [GMCnet] Dave Lenzi's modified upper A arms to increase caster.
| [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328243] |
Mon, 15 January 2018 11:59  |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
|
Senior Member |
|
|
This replacement 78 Royale drives better then our last one. I pulled Dave's knuckles, relay arm, idler arm, and the new steering wheel slip joint out of the burned Royale. Plus the upper A arms that had the offset rubber bushings installed. Already installed the knuckles. Not the relay, idler arm, or slip joint yet. Thinking of putting in the reworked A arms that Dave makes. Caster is extremely important for having the GMC drive perfectly straight. His pair of A frames are about $750. Thinking that I'll order some from his next run later this year. Any input out there? Bob Dunahugh. 78 Royale
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
|
|
|
|
| Re: [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328245 is a reply to message #328243] |
Mon, 15 January 2018 13:37  |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
I don't think they may be necessary on 77-78. Dave looked at my stock upper cams and they were all dead center after Cinnabar worked on it. He told me to crank the rear inboard and then go outboard with the front to keep camber neutral. It's a trade off game but I got 4 deg if I remember correctly both sides as a stopping point and she drives great with standard bushings.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
| Re: [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328246 is a reply to message #328243] |
Mon, 15 January 2018 14:44 |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
|
Senior Member |
|
|
Bob,
The max caster possible on Double Trouble with Moog offset bushings in the rear positions of the upper control arms was 1.9 and 2.0
degrees. It wandered. After installing a set of Dave's upper control arms in Houston I was able to get 6.0 degrees which I dialed
back to 5.0. Double Trouble now steers like it was on rails.
HOWEVER, I had NOT checked the steering box to determine if it was on high center before I installed Dave's upper control arms.
As I understand it on later coaches (77 & 78) changes were made and it is possible to get more caster. On the 77 Kingsley John
Sharpe and I completely rebuilt the front end and installed Moog offset bushings. We also set the steering box on high center.
Unfortunately we ran out of time (I was flying back to Sydney) so we didn't have time to align the front end so I can't tell you how
much caster was possible. I won't be able to provide that info until I return to Houston (March 27).
Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Bob Dunahugh
Sent: Tuesday, January 16, 2018 4:59 AM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] Dave Lenzi's modified upper A arms to increase caster.
This replacement 78 Royale drives better then our last one. I pulled Dave's knuckles, relay arm, idler arm, and the new steering
wheel slip joint out of the burned Royale. Plus the upper A arms that had the offset rubber bushings installed. Already installed
the knuckles. Not the relay, idler arm, or slip joint yet. Thinking of putting in the reworked A arms that Dave makes. Caster is
extremely important for having the GMC drive perfectly straight. His pair of A frames are about $750. Thinking that I'll order
some from his next run later this year. Any input out there? Bob Dunahugh. 78 Royale
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
|
|
|
| Re: [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328258 is a reply to message #328246] |
Mon, 15 January 2018 18:56 |
sgltrac
Messages: 2797
Registered: April 2011
Karma: 1
|
Senior Member |
|
|
In My 77 royale with stock upper arms and offset upper bushings I was able
to get a pair of fives for castor and it was a two finger driver pulling a
trailer.
And a sullybilt rear suspension kit.
Sully
77 eleganza 2
Bellevue.
On Mon, Jan 15, 2018 at 12:45 PM Rob Mueller
wrote:
> Bob,
>
> The max caster possible on Double Trouble with Moog offset bushings in the
> rear positions of the upper control arms was 1.9 and 2.0
> degrees. It wandered. After installing a set of Dave's upper control arms
> in Houston I was able to get 6.0 degrees which I dialed
> back to 5.0. Double Trouble now steers like it was on rails.
>
> HOWEVER, I had NOT checked the steering box to determine if it was on high
> center before I installed Dave's upper control arms.
>
> As I understand it on later coaches (77 & 78) changes were made and it is
> possible to get more caster. On the 77 Kingsley John
> Sharpe and I completely rebuilt the front end and installed Moog offset
> bushings. We also set the steering box on high center.
> Unfortunately we ran out of time (I was flying back to Sydney) so we
> didn't have time to align the front end so I can't tell you how
> much caster was possible. I won't be able to provide that info until I
> return to Houston (March 27).
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Bob
> Dunahugh
> Sent: Tuesday, January 16, 2018 4:59 AM
> To: gmclist@list.gmcnet.org
> Subject: [GMCnet] Dave Lenzi's modified upper A arms to increase caster.
>
> This replacement 78 Royale drives better then our last one. I pulled
> Dave's knuckles, relay arm, idler arm, and the new steering
> wheel slip joint out of the burned Royale. Plus the upper A arms that had
> the offset rubber bushings installed. Already installed
> the knuckles. Not the relay, idler arm, or slip joint yet. Thinking of
> putting in the reworked A arms that Dave makes. Caster is
> extremely important for having the GMC drive perfectly straight. His pair
> of A frames are about $750. Thinking that I'll order
> some from his next run later this year. Any input out there? Bob
> Dunahugh. 78 Royale
>
>
> _______________________________________________
> 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
Sully
77 Royale basket case.
Future motorhome land speed record holder(bucket list)
Seattle, Wa.
|
|
|
|
| [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster. [message #328271 is a reply to message #328243] |
Mon, 15 January 2018 21:59 |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
|
Senior Member |
|
|
I put a lot of Dave's parts in out first 78. Got it aligned. Did the same with a friend's 78. Both drove well. Just not as good as I thought they should. Bought this latest 78 with about 100,000 less miles that has all it's original parts. Drives better then the ones I fixed. It's got to be how the aligning is done. I know one other person that has had the same thing happen. Bob Dunahugh 78 Royale
________________________________
From: Bob Dunahugh
Sent: Monday, January 15, 2018 11:59 AM
To: gmclist@list.gmcnet.org
Subject: Dave Lenzi's modified upper A arms to increase caster.
This replacement 78 Royale drives better then our last one. I pulled Dave's knuckles, relay arm, idler arm, and the new steering wheel slip joint out of the burned Royale. Plus the upper A arms that had the offset rubber bushings installed. Already installed the knuckles. Not the relay, idler arm, or slip joint yet. Thinking of putting in the reworked A arms that Dave makes. Caster is extremely important for having the GMC drive perfectly straight. His pair of A frames are about $750. Thinking that I'll order some from his next run later this year. Any input out there? Bob Dunahugh. 78 Royale
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
|
|
|
|
| Re: [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster. [message #328276 is a reply to message #328271] |
Tue, 16 January 2018 05:58 |
|
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
|
Senior Member |
|
|
Bob,
Re the two GMC's you put Dave's parts in please advise:
1) What was the front ride height set at?
2) What was the rear ride height set at?
3) What was the camber setting?
4) What was the toe setting?
5) What was the caster setting?
6) Was the steering box set on high center?
7) Were the relay lever and idler arm 90 degrees perpendicular to the front cross member when the steering box was set on high
center?
Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Bob Dunahugh
Sent: Tuesday, January 16, 2018 2:59 PM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster.
I put a lot of Dave's parts in out first 78. Got it aligned. Did the same with a friend's 78. Both drove well. Just not as good as I
thought they should. Bought this latest 78 with about 100,000 less miles that has all it's original parts. Drives better then the
ones I fixed. It's got to be how the aligning is done. I know one other person that has had the same thing happen. Bob Dunahugh 78
Royale
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
|
|
|
|
| Re: [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster. [message #328336 is a reply to message #328276] |
Wed, 17 January 2018 09:43 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
|
Senior Member |
|
|
There is a coach around here that was owned by a city that didn't use it much but kept it well maintained.
This thing has the original steering shaft boot on it.
I got to drive it and it drove like a dream. It is an empty transmode, but still, it just drive like a car I tell you.
________________________________
From: Gmclist on behalf of Rob Mueller
Sent: Tuesday, January 16, 2018 5:58:26 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster.
Bob,
Re the two GMC's you put Dave's parts in please advise:
1) What was the front ride height set at?
2) What was the rear ride height set at?
3) What was the camber setting?
4) What was the toe setting?
5) What was the caster setting?
6) Was the steering box set on high center?
7) Were the relay lever and idler arm 90 degrees perpendicular to the front cross member when the steering box was set on high
center?
Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Bob Dunahugh
Sent: Tuesday, January 16, 2018 2:59 PM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] Fw: Dave Lenzi's modified upper A arms to increase caster.
I put a lot of Dave's parts in out first 78. Got it aligned. Did the same with a friend's 78. Both drove well. Just not as good as I
thought they should. Bought this latest 78 with about 100,000 less miles that has all it's original parts. Drives better then the
ones I fixed. It's got to be how the aligning is done. I know one other person that has had the same thing happen. Bob Dunahugh 78
Royale
_______________________________________________
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
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
|
|
|
|
| Re: [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328349 is a reply to message #328243] |
Wed, 17 January 2018 12:04 |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
|
Senior Member |
|
|
Gerald Works. Thanks for the wakeup call. I've been aware of what you brought up. And on this latest 78. Just haven't thought of the rear as much as I should have. I had checked for rear pins condition by the pry bar method. And have paid close attention to how the coach handled as trucks passed by for rear steer. But I failed to check rear alignment. A few years ago I had the opportunity to drive an extremely low mileage 78. It handled like a new car. Ours now drives very close to perfect. Just not there yet. I just might have a slightly bent rear arm. Or as I said. The rear pins FELT good. I need to pull the arms/pins, and mic those parts. ( GREAT. More to take apart ) Thanks again for the wakeup. Bob Dunahugh. 78 Royale
________________________________
From: Bob Dunahugh
Sent: Monday, January 15, 2018 11:59 AM
To: gmclist@list.gmcnet.org
Subject: Dave Lenzi's modified upper A arms to increase caster.
This replacement 78 Royale drives better then our last one. I pulled Dave's knuckles, relay arm, idler arm, and the new steering wheel slip joint out of the burned Royale. Plus the upper A arms that had the offset rubber bushings installed. Already installed the knuckles. Not the relay, idler arm, or slip joint yet. Thinking of putting in the reworked A arms that Dave makes. Caster is extremely important for having the GMC drive perfectly straight. His pair of A frames are about $750. Thinking that I'll order some from his next run later this year. Any input out there? Bob Dunahugh. 78 Royale
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
|
|
|
|
| Re: [GMCnet] Dave Lenzi's modified upper A arms to increase caster. [message #328351 is a reply to message #328349] |
Wed, 17 January 2018 12:33 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
|
Senior Member |
|
|
Bob, an easy way to check for bent bogie arms is to jack up the rear of the
coach under the bogie boxes, and remove the wheels and tires. Then, use a
long accurate straight edge and hold it firmly against the mounting flange
where the studs come out on the rear bogie arm. Then look at the forward
bogie flange where the straight edge meets the flange. It should sit
squarely across the flange. If there is a gap on the front and not on the
rear of the flange, then the arm is bent towards the frame of the coach, or
towed in. Opposite gap would be towed out.
Bending is the remedy. If there is slop in the bushings, there is
wear, and the pins and bushings need to be serviced.
Jim Hupy
Salem, Or
On Jan 17, 2018 10:05 AM, "Bob Dunahugh" wrote:
>
> Gerald Works. Thanks for the wakeup call. I've been aware of what you
> brought up. And on this latest 78. Just haven't thought of the rear as much
> as I should have. I had checked for rear pins condition by the pry bar
> method. And have paid close attention to how the coach handled as trucks
> passed by for rear steer. But I failed to check rear alignment. A few years
> ago I had the opportunity to drive an extremely low mileage 78. It handled
> like a new car. Ours now drives very close to perfect. Just not there yet.
> I just might have a slightly bent rear arm. Or as I said. The rear pins
> FELT good. I need to pull the arms/pins, and mic those parts. ( GREAT. More
> to take apart ) Thanks again for the wakeup. Bob Dunahugh. 78 Royale
>
> ________________________________
> From: Bob Dunahugh
> Sent: Monday, January 15, 2018 11:59 AM
> To: gmclist@list.gmcnet.org
> Subject: Dave Lenzi's modified upper A arms to increase caster.
>
> This replacement 78 Royale drives better then our last one. I pulled
> Dave's knuckles, relay arm, idler arm, and the new steering wheel slip
> joint out of the burned Royale. Plus the upper A arms that had the offset
> rubber bushings installed. Already installed the knuckles. Not the relay,
> idler arm, or slip joint yet. Thinking of putting in the reworked A arms
> that Dave makes. Caster is extremely important for having the GMC drive
> perfectly straight. His pair of A frames are about $750. Thinking that
> I'll order some from his next run later this year. Any input out there?
> Bob Dunahugh. 78 Royale
> _______________________________________________
> 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
|
|
|
|
Goto Forum:
Current Time: Sat Apr 20 01:28:02 CDT 2024
Total time taken to generate the page: 0.01108 seconds
|
GMCforum
Search
Help
Register
Login
Home
