![]() |
Register or Log In To remove these advertisements. |
|
|
View Poll Results: Which Engine? | |||
Big V6 |
![]() ![]() ![]() ![]() |
13 | 34.21% |
500 Caddy |
![]() ![]() ![]() ![]() |
25 | 65.79% |
Voters: 38. You may not vote on this poll |
![]() |
|
Thread Tools | Display Modes |
|
![]() |
#1 |
Registered User
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
|
Unique 500+ Cubic Inch Engine Swap
The smog 350 in my '72 K20 is tired. It uses a lot of oil and is now burning water as well. Over the past two years I have been collecting parts for an engine swap. I want to go big - I don't care about fuel mileage for this truck, I just frame twisting, tire roasting low end torque with good mid range. The kind that makes it easy and fun to drive around town and can hook on a trailer and never look back.
Anyways, I have a couple of options. No matter what I do, I will either be keeping the 4 speed and swapping in 3.54 gears or leaving the 4.10's (with a heavier axle of course) and swapping in an NV4500 or the like. Option number one that I have been leaning towards all along is a V6 GMC. I have all of the parts from a '68 GMC (Thanks Old_iron) so it would be a bolt in affair. I have a fresh 478M with a bad crank. Plan would be to offset grind the crank to fit BBC rods and custom pistons and cam to top it off. Should be in the 530 cubic inch range. Cost is going to be in the $4K range. The other option that intrigues me is a 500 Cadillac. Can pickup a good runner for less than $500. It would take a flywheel and adapter plate from Cad Company and a simple cam swap to get it up to snuff. Cost would be in the $2500 range. If it ever had to be rebuilt, the crank would also get ground to BBC specs and would end up in the 530 cubic inch range... Obviously the cost of the 500 is appealing, but I have always had a soft spot for big V6's as well. What do you all say? Caddy is unique, but the V6 even more so... |
![]() |
![]() |
![]() |
#2 |
Senior Member
![]() Join Date: Mar 2003
Location: Colfax-California
Posts: 8,549
|
Re: Unique 500+ Cubic Inch Engine Swap
If those were my only choices it would be caddy all the way. Stump pulling torque and probably better fuel mileage. The big V6s are absolute gas hogs, maybe 5-6 mpg. Caddy will get you possibly into the low teens
|
![]() |
![]() |
![]() |
#3 |
Registered User
Join Date: May 2016
Location: Fort Mohave, AZ
Posts: 367
|
Re: Unique 500+ Cubic Inch Engine Swap
If you want big - why not a 572 BBC. Tons of torque, hp and an endless supply of high hp parts out there.
Just my 2 cents worth.
__________________
1970 GMC 2500 700R Trans RideTech 4 link rear suspension - Air Bagged on all four corners 350 SBC 300hp Weiand Supercharger FiTech EFI |
![]() |
![]() |
![]() |
#4 |
Registered User
Join Date: Apr 2016
Location: Dawson Creek, B.C.
Posts: 143
|
Re: Unique 500+ Cubic Inch Engine Swap
Big V-6. I'm a sucker for oddball engines.
![]()
__________________
Nick 1961 Apache short stepside 4X4 SBW 348/4 speed 1960 Apache C-20 long fleet custom cab BBW 283/4 Speed 1967 rust bucket Olds Cutlass with a 455 1972 GMC K-15 350/4 speed long fleet |
![]() |
![]() |
![]() |
#5 |
Registered User
Join Date: May 2011
Location: Northern Calif.
Posts: 3,693
|
Re: Unique 500+ Cubic Inch Engine Swap
I also love oddball engines such as this....
|
![]() |
![]() |
![]() |
#6 |
Senior Member
![]() Join Date: Feb 2002
Location: Tucson, AZ USA
Posts: 7,275
|
Re: Unique 500+ Cubic Inch Engine Swap
What is it? I know, Late-War aircraft powerplant manufacturers were looking for ever bigger engines, but by the end of the period, were overtaken by jet engines, and piston engine development dead-ended in aviation.
__________________
Every 25 years I like to rebuild that 292, whether it needs it or not. |
![]() |
![]() |
![]() |
#7 | |
Registered User
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
|
Re: Unique 500+ Cubic Inch Engine Swap
Quote:
![]() Will probably end up with the V6 - the sound of an even firing order is truly mesmerizing. I think with a little head work and the right cam, 600 Ft Lbs of torque that has a curve similar to the top of my dinner table should be doable. ![]() |
|
![]() |
![]() |
![]() |
#8 | |
Registered User
Join Date: May 2016
Location: Fort Mohave, AZ
Posts: 367
|
Re: Unique 500+ Cubic Inch Engine Swap
Quote:
I've got a 1967 Olds Cutlass. I ran a Olds 455 in it for 35 years. When it came time to get serious about HP and torque I found a complete ready to run, balanced, blueprinted, dyno'd 518 HP/585 lbs torque 468 BBC crate engine from Vortech Pro, complete with carb, MDS Pro Billet distributor and valve covers, for about half the price to get that kind of HP and reliability out of the Olds 455. It also came with a one year warranty with unlimited miles. That and worse case if something fails there are a bazillion parts available for the BBC. Finding good parts for the GM V6 might be a issue. One more thing, a BBC in an Olds really pisses of the diehard Olds guys. You might want to rethink the cost of a 'unique' killer motor. 468 BBC in a 1967 Cutlass. ![]()
__________________
1970 GMC 2500 700R Trans RideTech 4 link rear suspension - Air Bagged on all four corners 350 SBC 300hp Weiand Supercharger FiTech EFI |
|
![]() |
![]() |
![]() |
#9 |
Senior Member
![]() Join Date: Aug 2004
Location: Centennial, CO
Posts: 2,951
|
Re: Unique 500+ Cubic Inch Engine Swap
Caddy! You’ll love the low end torque. A cam and spring swap will wake it up significantly. Take a look at the Cadillac power message board. https://cadillacmagazine.com/forums/...k-cadillacs.3/
If it needs rebuilt find someone good to do the machine work, someone that knows them or is willing to do the research. Maybe even send it to Courtney at CadCo
__________________
ClusterTruck: 68 C10 Bought in 89, wrecked in 03. Slow low $ rebuild started '17. 6.0 & TKO http://67-72chevytrucks.com/vboard/s...d.php?t=788602 93 K1500 Short Step, 350, NV4500, EBL flash ECU. Vortec heads & roller cam someday... 05 Jeep Wrangler Unlimited. 3” lift & 6-speed 02 E320 the insurance total “free car” 13 Tahoe LTZ Last edited by clay68c10; 11-14-2019 at 09:01 AM. |
![]() |
![]() |
![]() |
#10 |
Special Order
![]() ![]() Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,859
|
Re: Unique 500+ Cubic Inch Engine Swap
If it's to get that grunt either engine would be good for providing, and nothing else but cool factor, I would go the big V6. And if you want to build it up, even better. The Caddy I would also really like in that truck. But you don't get that different sound only a V6, and even only a GMC V6 (especially a big truck one) makes moving it along. It's also a bygone American truck sound once quite familiar to all (over a certain age). Just keeping that alive is awesome. All these great running modern diesels out there, but you hear a Detroit and it just does something. Same thing here.
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ |
![]() |
![]() |
![]() |
#11 |
Proprietor of Dale's Corner
![]() Join Date: Nov 2012
Location: Vacaville , CA
Posts: 16,115
|
Re: Unique 500+ Cubic Inch Engine Swap
I wouldn't choose either of the choices. I have a .030 over 396 (402) in my truck. It has outstanding torque, power to do most anything.
__________________
"Some Days Chickens And Some Days Feathers" Dale XNGH ECV Sam Brannan 1004 R.I.P. 67ChevyRedneck R.I.P. Grumpy Old Man |
![]() |
![]() |
![]() |
#12 |
Registered User
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
|
Re: Unique 500+ Cubic Inch Engine Swap
I used to think a 427 tall deck Chevy had torque - then I drive my brother's Highboy with a 472 Caddy....
|
![]() |
![]() |
![]() |
#13 |
Registered User
Join Date: Jul 2002
Location: St. James, MO
Posts: 1,239
|
Re: Unique 500+ Cubic Inch Engine Swap
V6 for the sheer joy of it. I have had experience with only one of those Caddy motors, but I was not impressed.
__________________
'69 Longstep K-10: 327/SM465/T-221/Closed Knuckle Dana44/12-bolt. |
![]() |
![]() |
![]() |
#14 |
Registered User
Join Date: Feb 2012
Location: Lakeway, TX
Posts: 335
|
Re: Unique 500+ Cubic Inch Engine Swap
V6 for sure
__________________
1972 GMC Sierra Grande (current truck) 1980 Chevy Stepside (gone) 1987 Chevy Blazer (gone) 1972 Chevelle SS Convertible (gone) 1973 Chevy Corvette (gone) 1967 Chevy Camaro (STOLEN!) |
![]() |
![]() |
![]() |
#15 |
Go Pack Go!
Join Date: Nov 2005
Location: Green Bay
Posts: 2,669
|
Re: Unique 500+ Cubic Inch Engine Swap
There's a few members that choose a 500 Caddy.
|
![]() |
![]() |
![]() |
#16 |
All about them K’s
![]() Join Date: Jun 2014
Location: Land of Entrapment
Posts: 6,388
|
Re: Unique 500+ Cubic Inch Engine Swap
That V6 would be awesome. I hope you can go that route, I’d love to see it come together.
__________________
Tyler '57 3100 http://67-72chevytrucks.com/vboard/s...d.php?t=813888 '72 K20 Cheyenne: 5” lift, 35’s, front dana 60 blah blah blah… http://67-72chevytrucks.com/vboard/s...d.php?t=662879 ‘69 K10 SWB: 4” lift 33”s… in a million pieces http://67-72chevytrucks.com/vboard/s...d.php?t=805206 '98 Silverado LT K2500HD ECLB Vortec 454/4l80E: 6" lift 315/75/16's |
![]() |
![]() |
![]() |
#17 | |
The Older Generation
![]() ![]() ![]() Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,505
|
Re: Unique 500+ Cubic Inch Engine Swap
Quote:
As long as you are looking for something unique with lots of torque why not use a GMC 702 V12.... ![]() Picture from this thread: http://67-72chevytrucks.com/vboard/s...d.php?t=254111 LockDoc
__________________
Leon Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles (My Dually Pickup Project Thread) http://67-72chevytrucks.com/vboard/s...d.php?t=829820 - |
|
![]() |
![]() |
![]() |
#18 | ||
Registered User
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
|
Re: Unique 500+ Cubic Inch Engine Swap
Quote:
Quote:
![]() |
||
![]() |
![]() |
![]() |
#19 |
Registered User
Join Date: Oct 2019
Location: Abbotsford, BC
Posts: 64
|
Re: Unique 500+ Cubic Inch Engine Swap
I vote the 500 Caddy. I had a 66 Caddy with a 429 in it. It moved that 6600lbs with no complaints. I can just imagine what the extra grunt of the 500 would do.
|
![]() |
![]() |
![]() |
#20 |
Registered User
Join Date: Jul 2002
Location: St. James, MO
Posts: 1,239
|
Re: Unique 500+ Cubic Inch Engine Swap
I had a '78 Caddy with the 472. It was a dog, just as sluggish as my old '66 Bel Air with the 230 I6.
__________________
'69 Longstep K-10: 327/SM465/T-221/Closed Knuckle Dana44/12-bolt. |
![]() |
![]() |
![]() |
#21 | |
Post Whore
![]() Join Date: Feb 2016
Location: Portland Oregon
Posts: 11,154
|
Re: Unique 500+ Cubic Inch Engine Swap
Quote:
![]() Here's a couple of torque monsters. First one is a 30 cylinder Mopar and if that is too hard to accept. The second one is GM's 12 cylinder version. Here's the whole story. http://www.theshermantank.com/sherma...to-production/
__________________
Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. ![]() RIP Bob Parks. 1967 Burban (the WMB),1988 S10 Blazer (the Stink10 II),1969 GTO (the Goat), 1970 Javelin, 1952 F2 Ford OHC six 4X4, 29 Model A, 72 Firebird (the DBP Bird). 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377 Last edited by HO455; 11-14-2019 at 11:05 PM. |
|
![]() |
![]() |
![]() |
#22 |
Registered User
Join Date: Jul 2015
Location: North East PA
Posts: 682
|
Re: Unique 500+ Cubic Inch Engine Swap
Your 78 caddy had a 425 not a 472 , The 500 is the engine to go with , the install would go easier if it was a 500 out of a eldorado then you would not have to find a oil pan for clearence issues . and if you took all the money that it would take to build that V6 to 530 hp and put it in a true 500 not 472 you would proberly be on the threshold of 800 hp. and also understand that these engines were built by cadillac so they recieved the best of the best, those blocks were the best and strongest Gm ever built in that generation.
|
![]() |
![]() |
![]() |
#23 |
Registered User
Join Date: Jul 2002
Location: St. James, MO
Posts: 1,239
|
Re: Unique 500+ Cubic Inch Engine Swap
You're right: my brain hiccough.
Still, I have no respect whatever for the supposedly awesome Caddy engines. It was disappointing in every way and not fundamentally different from the "superstar" 500.
__________________
'69 Longstep K-10: 327/SM465/T-221/Closed Knuckle Dana44/12-bolt. |
![]() |
![]() |
![]() |
#24 |
Senior Member
![]() Join Date: Mar 2003
Location: Colfax-California
Posts: 8,549
|
Re: Unique 500+ Cubic Inch Engine Swap
From about 1973 and newer all the big cube engines were facing lower compression and retarded cams to meet emission requirements. I think the 454 got down to about 7.5 to 1 compression. Doesn't take much to wake them up. Jump them up to about 9-1 and add a mild cam and make those cubic inches come alive. Night and day difference
|
![]() |
![]() |
![]() |
#25 |
Registered User
Join Date: Oct 2010
Location: Yakima Valley, Washington
Posts: 578
|
Re: Unique 500+ Cubic Inch Engine Swap
The 500 Cad would get the vote a hundred times over from me. I love oddball as much (probably more than) the next guy but that v6 was an odd duck that was put down for a reason.
Caddy bb is a marvel. Huge power/torque, moderately light (lighter than bbc) and as mentioned efficient enough to give decent mileage. 3 to 4 times what the v6 will give. The v6s I was around averaged 4 mpg. Very discouraging and it won't turn the rpm the 500 will.
__________________
1951 GMC 250 Open Express Pickup 1968 Suburban C10 1971 C20 Olive “People are shocked when they find out I’m not a good electrician” Dad told me “Son, never strike a man in anger- unless you’re certain you can get away with it” |
![]() |
![]() |
![]() |
Bookmarks |
|
|