The Original Envoy

aaserv

Original poster
Platinum Donor
Dec 1, 2019
351
N of Baton Rouge, La.
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HARDTRAILZ

Moderator
Nov 18, 2011
49,661
I like it
 
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Mooseman

Master Blaster
Moderator
Dec 4, 2011
22,548
Ottawa, ON
Well, I can tell you it was from an Ottawa dealer, Belisle. No longer in existence. Had been here forever and just closed up shop in 2012. Funny enough, my Caprice was also originally from that dealership.

I can't even tell who made that but since it was sold through a GM dealership, it was a GM?
 

BrianF

Hobbyist
Jul 24, 2013
993
West central Sask.
My buddy has an envoy epic. I think his dad got it or some family member got way back in the early 60s. We got her going in the late 90s and would cruise it around using a gravity fed Jerry can because the fuel pump was shot. Around 2008 he rebuilt the engine and fuel pump, it went not bad!!
 

Mooseman

Master Blaster
Moderator
Dec 4, 2011
22,548
Ottawa, ON
Did it ever have "crank, no start issues"? :dielaugh:
 

Reprise

Lifetime VIP Donor
Jul 22, 2015
2,544
@northcreek - thanks for linking the Wiki article. :tiphat: After looking at it, my two faves were the FB station wagon and the HB estate wagon (yeah, I'm goofy that way)
 

5tjss

Registered Member
May 19, 2022
10
Loco, Oklahoma
If the heart of the truck is the engine, then my Envoy's lineage traces back to this feat of 80's engineering. It's a fascinating read, GM wasn't willing to gamble so the engineers built the first one in the garage at home. 900 HP from a 4 cylinder got management's attention, and the rest is history. I'm a little intimidated by the head design, which I'll have to remove soon for maintenance. I'm told it's the only engine that runs at 10:1 compression, that doesn't run on jet fuel.
 

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Mooseman

Master Blaster
Moderator
Dec 4, 2011
22,548
Ottawa, ON
@5tjss , head R&R on these is a total bitch. Broken head bolts, access to timing components, the cost of rebuilding the head. Might as well just throw in a good used engine. Some have done it successfully after swearing it off forever. The broken head bolts is the worst part and it ALWAYS the rear more difficult ones.
 
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5tjss

Registered Member
May 19, 2022
10
Loco, Oklahoma
@5tjss , head R&R on these is a total bitch. Broken head bolts, access to timing components, the cost of rebuilding the head. Might as well just throw in a good used engine. Some have done it successfully after swearing it off forever. The broken head bolts is the worst part and it ALWAYS the rear more difficult ones.
Mooseman, I have been researching this for the last 6 months, and I have yet to come across anyone who has dealt with it, who had an opinion different from everything you just said. I've got the GM dealership shop manuals, and it's only my aversion to spending money that has kept the idea alive after going through those pages. It's like nothing else that has been produced, all traditional wisdom about heads, gaskets, etc goes out the window. Not many places to turn for experience backed guidance if it gets hairy (and you know damn well it will get hairy) because most folks had enough sense to walk away from it.

Local shops want around 3 grand, a rebuilt crate engine, ready to install, crate delivered in my driveway, is the same price. I've had difficulty finding a used engine because every one that's been junked have died of the same issue. Overheated and eventually became undriveable and too costly to repair, so Pull-A-Part got some more Envoy's. Every single one. Clearly that's a design flaw. I'm thinking the hardware isn't durable enough for the forces produced at times, and starts failing and it cascades into other components. Flimsy thin parts, and that's what happens when they start letting the marketing department have a say in the design work over in the engineering department. I had a 1970 Nova when I was 16, paid $200 for it. Straight six, got real hot one day and cracked the block, but i drove it 2 more years and the all-steel radiator never blinked. I could stand inside the engine compartment while working on it. I like this truck and it has a great history and story to tell, I love what the unusual design can do at certain times for performance, but I need some tougher components. This chinese paper-aluminum crap is out. And whoever it was over at GM, who thought making plastic radiators was a good idea, needs their butt whipped out in the street for that.

Any info on heavy-duty rebuilds? or component suppliers? General guidance on what a guy should do with a truck in this condition? I'll bail and go find a 1970 Nova if the general consensus is to get out while you can. A 4-door granny Nova is still findable, nobody looks cool in those. Except me. 💩
 

Mooseman

Master Blaster
Moderator
Dec 4, 2011
22,548
Ottawa, ON
I dunno about design flaws. The vast majority of these engines outlast the truck body or tranny, which were the reasons I sent mine to scrap with a perfectly fine engine. This, and any engine will warp the head(s) if overheated.

I'll point you to this thread that the head job that ended in failure.


You could probably find a good used engine for less than half that price, like this one:

Car-part.com also shows quite a few just in OK.
 

TollKeeper

Guru
Dec 3, 2011
6,886
Brighton, CO
I'm pretty sure I saw a couple 4.2 engines on Craigslist recently in his area of the country.
 

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