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Re: new engines for the GMCs [message #316595 is a reply to message #316311] Tue, 25 April 2017 12:24 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Since the title of this thread is new engines and not just LS conversions, let me throw this out.

Has anyone looked at the Caddy Northstar. The supercharged version had gobs of horsepower and torque and bolted up to a modern FWD overdrive tranny. I don't know anything about the rear end ratio but the performance versions of the Caddy could really scoot so I'm thinking multiple ratios were available.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: new engines for the GMCs [message #316596 is a reply to message #316595] Tue, 25 April 2017 12:49 Go to previous messageGo to next message
jknezek is currently offline  jknezek   United States
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kerry pinkerton wrote on Tue, 25 April 2017 13:24
Since the title of this thread is new engines and not just LS conversions, let me throw this out.

Has anyone looked at the Caddy Northstar. The supercharged version had gobs of horsepower and torque and bolted up to a modern FWD overdrive tranny. I don't know anything about the rear end ratio but the performance versions of the Caddy could really scoot so I'm thinking multiple ratios were available.



I'm pretty sure someone poured cubic dollars into this about the time I joined, close to a decade ago. I think it eventually got abandoned? Don't quote me on that. I'm turning 39, not 29, so anymore, so my kids have turned my memory for anything besides where they need to be when into mush...


Thanks,
Jeremy Knezek
1976 Glenbrook
Birmingham, AL
Re: new engines for the GMCs [message #316597 is a reply to message #316596] Tue, 25 April 2017 12:52 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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jknezek wrote on Tue, 25 April 2017 12:49
...my kids have turned my memory for anything besides where they need to be when into mush...
Blame your kids if you want, but that has nothing to do with it. Wait until you hit 49 or 59, or ... what was I saying?
Re: [GMCnet] new engines for the GMCs [message #316599 is a reply to message #316595] Tue, 25 April 2017 13:25 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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'Way, 'way back, Pete Pappas bought a Northstar front end and spent many
hours contemplating its possibilities for the GMC. I sat with him through
some of that. Neither of us could visualize any way to meld the two;
certainly not without a new front frame clip.

He abandoned the idea and instead RV'd an RTS bus. Seemed think that was
easier, even if it did take him a couple of years. :-)

Ken H.


On Tue, Apr 25, 2017 at 1:24 PM, Kerry Pinkerton
wrote:

> Since the title of this thread is new engines and not just LS conversions,
> let me throw this out.
>
> Has anyone looked at the Caddy Northstar. The supercharged version had
> gobs of horsepower and torque and bolted up to a modern FWD overdrive
> tranny.
> I don't know anything about the rear end ratio but the performance
> versions of the Caddy could really scoot so I'm thinking multiple ratios
> were
> available.
> --
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: new engines for the GMCs [message #316665 is a reply to message #316311] Wed, 26 April 2017 21:14 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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Northstars had headbolt issues, no? If you're looking at transverse mount, the LS4 in the Grand Prix GXP would be another option...


But really, we should probably all be jumping on the Manny diesel kit. If we could get some volume going, that really would be the best option.


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: [GMCnet] new engines for the GMCs [message #316674 is a reply to message #316665] Thu, 27 April 2017 06:04 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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I'll repeat what I wrote on FB: I'll wait for in-wheel e-motors come
available like the once done for the rear wheels of a Honda in
midwestern university. Couple that with a smaller engine up front, and
you are golden, imho.

Diesel sounded good a while ago, but with changes in laws in Europe,
Diesel will not be so good anymore, due to city-drive restrictions. My
0,02EUR

--
Best regards

Peer Oliver Schmidt
the internet company
PGP Key ID: 0x83E1C2EA


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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: new engines for the GMCs [message #316676 is a reply to message #316311] Thu, 27 April 2017 06:34 Go to previous messageGo to next message
rcjordan   United States
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Location: Elizabeth City, North Car...
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>diesel

After hearing the noise produced by the coach with Manny's diesel, I'm far less interested in the conversion.


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: [GMCnet] new engines for the GMCs [message #316686 is a reply to message #316676] Thu, 27 April 2017 09:08 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Noise from diesel engines is much less of a problem as the years go by. I
put a fancy sound system in my coach complete with tri-axial speakers and a
cd player. Haven't turned it on in years. Installed a flat screen tv. Took
it out. Never turned it on, either. Nothing but DRIVEL on it. Much rather
enjoy my panoramic view and visiting with my GMC friends. Just how we roll.
But, I am an engine guy, I want to hear it run. My sister has a different
philosophy, when her engine makes unusual noises, she turns up the volume
control. Different strokes.
But, significant noise reduction is possible with some excellent
damping materials available today. I covered my ONAN compartment with
DYNAMAT, and followed it with pet proof carpet padding. You can still hear
it, but much more tolerable. If you really value quiet operation vs fuel
economy, use a Ford V-10 Triton. Very quiet at 6 miles per gallon. A good
diesel will triple that mileage, and outlast two Triton's.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Apr 27, 2017 4:35 AM, "RC Jordan" wrote:

>> diesel
>
> After hearing the noise produced by the coach with Manny's diesel, I'm far
> less interested in the conversion.
> --
> 77 Royale Coachmen Side Dry Bath
> 76 Birchaven Coachmen Side Wet Bath
> 76 Eleganza
> Elizabeth City, NC
>
>
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Re: new engines for the GMCs [message #316692 is a reply to message #316311] Thu, 27 April 2017 11:22 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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A run around the block with Bounds was to a degree noisy.... but I think the bulk of the noise could be shut up with some thought and more sound deadening. As to mileage, I don't think 18 is gonna happen in a GMC until you transplant a different transmission. If then. However, get 12 - 14 and your fuel costs are the same as the gas ones or a bit less.
Putting a different gasoline engine in a GMC using the THM-425 (with the exception of the Cadillac) seems to me an exercise in 'can I do it'. More power to those who do. But it does nothing for the coach in my uses.

--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
Re: [GMCnet] new engines for the GMCs [message #316695 is a reply to message #316692] Thu, 27 April 2017 11:41 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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I once put a 354 Chrysler Hemi in a 1934 Ford 5 window. Along with B&M
Hydrostik. 8 Stromberg 2 barrel carbs on a Homemade "log" manifold. MERCURY
STATION WAGON rear end with 3:90 to 1 rear end gears. It fit with the aid
of a Sawzall and oxy/acetylene torches. Hell of a lot of work, for a
brutal, Ill handling beast of a bump steering, front end heavy, monster.
Went like jet stink in a straight line. Got 3 or 4 miles per gallon.
Sounded really "bad" with all those carbs and the Chet Herbert Roller Cam.
Today, wouldn't have it on a bet. Funny how stuff changes.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Apr 27, 2017 9:23 AM, "Johnny Bridges via Gmclist" <
gmclist@list.gmcnet.org> wrote:

> A run around the block with Bounds was to a degree noisy.... but I think
> the bulk of the noise could be shut up with some thought and more sound
> deadening. As to mileage, I don't think 18 is gonna happen in a GMC until
> you transplant a different transmission. If then. However, get 12 - 14
> and your fuel costs are the same as the gas ones or a bit less.
> Putting a different gasoline engine in a GMC using the THM-425 (with the
> exception of the Cadillac) seems to me an exercise in 'can I do it'. More
> power to those who do. But it does nothing for the coach in my uses.
>
> --johnny
> --
> 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
>
>
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Re: new engines for the GMCs [message #316698 is a reply to message #316311] Thu, 27 April 2017 13:52 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Not counting Hal's, which are a cut above, the best two transplants I've seen at least for use, were a Sideoiler a friend put in a '56 Crown Victoria and my little Ranger. Both added some steam without screwing up the original to any great degree. The Cadillac engine in our coaches is the same sort of improvement. And if you want 'silly' you can give it the JimK treatment - punch it out to 540 CID and hang a pair of turbos on.

--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
Re: new engines for the GMCs [message #316703 is a reply to message #316692] Thu, 27 April 2017 14:51 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Johnny Bridges wrote on Thu, 27 April 2017 11:22
...Putting a different gasoline engine in a GMC using the THM-425 (with the exception of the Cadillac) seems to me an exercise in 'can I do it'. More power to those who do. But it does nothing for the coach in my uses.

--johnny


I'd agree and I'm firmly in the 'just because I can camp...' FIRMLY! A different engine with the same tranny just isn't feasible as long as we can still get parts and cores for the Olds/Caddys.

I have a fresh 500 sitting at John Beavers shop waiting run-in. It's going in the car hauler. If I could find a good deal on a modern 5 speed OD tranny and transfer case I'd see if I could adapt it to the 1 ton hubs using a generic GM differential similar to what Hal StClair did. I think it would be doable and we'd have a jillion rear end ratios available for cheap. There are no shortages of Caddy cores. I'd consider doing this...'just because I can...'Smile Of course if I can adapt a Caddy to a new tranny, adapting a LS motor would be a snap. Plus I don't have to worry about steps or hatches but I'd try to work within those constraints just because it would be good to know.

I'm also planning on installing a Chevy 1 ton front end but will make new control arm mounts and use the stock control arms.

I'm going to pull the subframe from the parts coach that will become the car hauler and do all this fab work on my welding table so I can jig everything up.

I wish I lived near to some of you guys. This would be a lot more fun working with someone.

Anyone got a 5 speed auto and transfer case they want to swap for a good Honda EV6010?



Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: [GMCnet] new engines for the GMCs [message #316727 is a reply to message #316482] Thu, 27 April 2017 21:17 Go to previous messageGo to next message
richshoop is currently offline  richshoop   United States
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I find these replacement engine ideas very interesting, but the nearer term problem for all of us is the transmission. What can be done to come up with a replacement? We are quickly running out of rebuild kits.

----- Original Message -----

From: "Mike Sadlon"
To: gmclist@list.gmcnet.org
Sent: Sunday, April 23, 2017 7:29:14 AM
Subject: Re: [GMCnet] new engines for the GMCs

First, This isn't about mileage or even cost. Anything that goes round and round will wear out.
My GMC burns about 1 quart of oil every 500 miles, and I am OK with that vs. the cost of a rebuild.

Second, the last 455 casting was done sometime in the 70's. When I helped out at my buddies engine shop, about 50% of the engines that came in for a
simple rebuild, took some kind of major component. That's why the top shops are quoting $7500 for a rebuild. It is not customer friendly to say $5000
and to then come back and say you need another $1500 because your block won't take a rebuild. The rarer the more money.

Third. The LS would be a perfect motor, if it would bolt up with just an adaptor(that are out there cheap), a custom oil pan and front mount(easily
fabricated). You could sell those parts for around $500 and be OK making them. So a $500 kit, $2500 late model low mileage junk yard engine,$400 wire
harness and $300 computer tune and your running.

I will make a kit to bolt up the LS to the 425 transmission. But It needs custom front mount, rear mount, oil pan, trans pan, and an adaptor between
the differenial and the trans. I am looking at $1800 to $2000 for those parts. And to fit our coaches, you are going to have to add 3 inches to the
height of the step near the transmission to make it work. And it is getting real close to the hatch. it may even need to be raised a little to clear
the truck intake.

So what are the other choices?

To me there are 2 that make sense.

First the more expensive. World Product sells and engine called the LS hybrid. It is small block Chevy based bottom end, set up to take LS cylinder
heads. Again, it is not cheap. The first quotes on the short block exceed $5500! With a fresh set of heads and all the other component, It will
probably be near $10,000 for complete engine ready to drop in. But you will get easily 450 HP and 500 torque.

As always speed costs.

The other option is GM sells a motor they call HT383. Google it. It has almost the exact horsepower and torque of our stock 455s. The front mount and
pan prototypes will be done soon. you will have to raise the hatch, and I will let everyone know how much soon. Jegs has the motor for $4500. It has
a 2 year 50,000 mile warrantee. Add a Fitech fuel injection and you would have a great motor for our coaches. Keep in mind all your front accessories
need to be changed. But GM does sell a kit with everything you need, brand new, for about $1000.

How much is brand new worth vs. 40 year old everything!











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Re: new engines for the GMCs [message #316766 is a reply to message #316589] Sat, 29 April 2017 01:31 Go to previous messageGo to next message
Hal StClair   United States
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TR 1 wrote on Tue, 25 April 2017 08:33
Mike, I'm sorry if I came off as saying you were not capable of doing the swap. That was not my intention. My point in listing all that stuff out was to illustrate the point that engine swaps are a lot of work... And that the 455 and Cad 500 really are good motors for our application. You are 100% right, at some point we will NEED a new engine option... I also agree with you that the LS motor is the best gas engine out there right now for the job. But good god, it's a lot of work to get it in there and working, then add all the ancillaries as well...

But you are also correct in saying that the more options we have, the better off we will all be. I'll tell you, if I were going to do an LS swap on the GMC, and I needed to modify the interior anyway, I would probably look the possibility of using a 4L80 to get the extra gear and lockup converter.... I believe Hal's diesel setup uses a 4L80 or similar, and some sort of transfer case to get power back to the front...

Hal, could you maybe describe how your setup works?



Been out of town for a few days, sorry.
I used a 4l80e behind the H1 Hummer 6.5 with B/W transfer case I located from Revcon MH. Although the transfer case is all but impossible to locate today, one could use a NP205 TC which are easy to find and adaptors are readily available. I ran forward to a late model 9.25" AAM differential with custom built equal length half shafts. These front diff's are available from 2011 up 1 ton Chevy/GMC trucks. Ratios are somewhat limited with 3.73 the fastest offered from GM although a 3.42 was offered by AAM which is what I'm running now.
6.5's were never available with more than 4 speeds (auto's that is) as far as I know so any 6,8,or 10 speeds would have to be specially programmed and built to handle the diesels needs. A 4l80e can be modified to have 5 or 6 speeds but it's an expensive process which requires internal gear ratio changes to fully exploit the gear splits. A stand alone ECU would be required and you would loose the engine PCM's interface with the transmission which would probably cause drivability issues. The 4 speed with the locking convertor seems to work very well and with the diesels high torque at modest rpm's requires very limited downshifting.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: new engines for the GMCs [message #316770 is a reply to message #316311] Sat, 29 April 2017 07:38 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Check your PMs Hal

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: new engines for the GMCs [message #316870 is a reply to message #316766] Mon, 01 May 2017 06:28 Go to previous message
TR 1 is currently offline  TR 1   United States
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Hal StClair wrote on Sat, 29 April 2017 01:31
one could use a NP205 TC which are easy to find and adaptors are readily available.
Hal


NP205 is an interesting idea, Hal... And I think I'd like the idea of having a low range available if I needed the torque....


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
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