63 small block conversion - The 1947 - Present Chevrolet & GMC Truck Message Board Network

owen13 · 06-13-2009, 11:04 PM

hey guys i am new to the forums here and was hoping you may be able to shed some light on a couple of things for me. i recently purchased a 63 gmc half ton with the 305 v6 and was wondering what would be required to do a small block conversion? any ideas or past experiences you could share would be awesome i just want to know what i might be getting myself into

daverod · 06-14-2009, 12:00 AM

I'm thinking it would be easy. But then I don't know a hell of a lot. Maybe different engine mounts,bigger radator and your good to go. People do it all the time. I'm sure Joe knows he seems to know all things.

owen13 · 06-14-2009, 08:33 PM

awesome

any idea if the bell housings on those big v6's are the same as the SB chevy's?

TwiggyTheDrummer · 06-14-2009, 08:48 PM

Welcome man! I have a '63 GMC with the 305 V6 and unlike you I chose to keep it though I have the plaid valve covers which made that desirable. If you want to convert to a SBC you will need different mounting brackets and to use some creativity. You should be able to find these brackets on various websites or ask around here. As far as the trans goes, the 305 requires an adapter plate in order for any other trans to be mounted up to it. I opted for a used '63 Powerglide that we bought from a guy who luckily also had a original adapter plate. Any trans can be bolted behind it once you add the adapter though the stock 3-speed does not require it. And the bell housing is akwardly offset in comparison.

**Captainfab** · 06-14-2009, 11:19 PM

I can fix you up with the SBC frame brackets for the motormounts. What trans are you going to run? If you are going to keep the SM420 4 speed then you'll need to change the bellhousing as well.......have them too.

TwiggyTheDrummer · 06-14-2009, 11:21 PM

Jeeze, Captain. Why couldn't I have found you guys when I needed a trans and a hood. Of course I joined after I bought those items.

owen13 · 06-15-2009, 07:00 AM

awsome good to know captn, whats cost like for the mounts and the bell housing? i have also been toying with doing a turbo350/400 wich ever i can find were im shooting for a daily driver that may be the way to go anyway

**Captainfab** · 06-16-2009, 12:00 AM

PM sent.

owen13 · 06-16-2009, 11:49 AM

Ok so captain now has me wondering what year of truck I actually have, besides the clutch linkage what are some differences I can look for to differentiate between 60-62 and 63 wich is what the vehicle is titled as

MacAttack · 06-16-2009, 12:24 PM

Welcome owen13 - this is what this site's all about.

Plenty of help and, of course - demands for pics of your rig. (Friendly Warning)

Mac.

**Corts60** · 06-16-2009, 12:43 PM

1963 is the only year truck that has coil front suspension and a wrap-a-round windshield. That should help you determine what year you have.....

Oh, and

owen13 · 06-16-2009, 05:09 PM

haha thanks for the warm invite guys

, i have not dug out the truck quit literaly but here are the pics that i do have of it, it does have coil fronts and the wrap around windshield but it does also have the combo brake/clutch master which i have heard was only on the 60-62 model years. could this be because it is a custom?

ill get some better pics once i get it out of its hole

Joemomma1 · 06-16-2009, 05:40 PM

Nice, a custom. I pulled the same 305 setup in favor of a 350/th350 and am happy with it. Its nice to be all original but to me it was not practical keeping that engine/tranny combo for a daily driver.

owen13 · 06-16-2009, 05:44 PM

yeah i am in the same boat, i had a 61 3/4 ton with that engine trans combo and know how poorly they do as a daily driver that's why i am looking to do the change over

**Captainfab** · 06-16-2009, 11:01 PM

It's quite possible that it is an early '63 and they were just using up the previous years parts. That or is it possible that the hydraulic clutch was standard for the '63 GMC's ? Most of my experience has been with Chevy's.....

TwiggyTheDrummer · 06-16-2009, 11:04 PM

Standard clutch. Same thing on mine.

06-13-2009, 11:04 PM	#1
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	63 small block conversion hey guys i am new to the forums here and was hoping you may be able to shed some light on a couple of things for me. i recently purchased a 63 gmc half ton with the 305 v6 and was wondering what would be required to do a small block conversion? any ideas or past experiences you could share would be awesome i just want to know what i might be getting myself into

06-14-2009, 12:00 AM	#2
daverod SSN 706 Join Date: Mar 2009 Location: Pocatello Idaho Posts: 3,821	Re: 63 small block conversion I'm thinking it would be easy. But then I don't know a hell of a lot. Maybe different engine mounts,bigger radator and your good to go. People do it all the time. I'm sure Joe knows he seems to know all things. Last edited by daverod; 06-14-2009 at 12:01 AM.

06-14-2009, 08:33 PM	#3
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	Re: 63 small block conversion awesome any idea if the bell housings on those big v6's are the same as the SB chevy's?

06-14-2009, 08:48 PM	#4
TwiggyTheDrummer Keep It Simple Stupid.. Nope.. Join Date: Jan 2009 Location: Live Oak, FL Posts: 665	Re: 63 small block conversion Welcome man! I have a '63 GMC with the 305 V6 and unlike you I chose to keep it though I have the plaid valve covers which made that desirable. If you want to convert to a SBC you will need different mounting brackets and to use some creativity. You should be able to find these brackets on various websites or ask around here. As far as the trans goes, the 305 requires an adapter plate in order for any other trans to be mounted up to it. I opted for a used '63 Powerglide that we bought from a guy who luckily also had a original adapter plate. Any trans can be bolted behind it once you add the adapter though the stock 3-speed does not require it. And the bell housing is akwardly offset in comparison. __________________ 1963 GMC SWB Fleetside in Sunburst Orange Metallic 305E V6 w/ Plaid VC, Powerglide, BOSS 313 20" Chrome Wheels, Kumho Ecsta STX 275/45/R20's, Alpine/Clarion System, Dynomax Exhaust Old custom classic trucks have soul. Their dashboards aren't plastic, and they've survived both the best and worst of what the 20th century had to offer. For the owners of these trucks, it's often the same story. Through both good and bad times they persevered, until one day they could turn the key and roll up in a customized truck everyone with good taste would admire. – Custom Classic Trucks Last edited by TwiggyTheDrummer; 06-14-2009 at 08:49 PM.

06-14-2009, 11:19 PM	#5
Captainfab 60-66 Nut Join Date: Mar 2007 Location: Coeur d'Alene, Idaho Posts: 23,246	Re: 63 small block conversion I can fix you up with the SBC frame brackets for the motormounts. What trans are you going to run? If you are going to keep the SM420 4 speed then you'll need to change the bellhousing as well.......have them too. __________________ Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE

06-14-2009, 11:21 PM	#6
TwiggyTheDrummer Keep It Simple Stupid.. Nope.. Join Date: Jan 2009 Location: Live Oak, FL Posts: 665	Re: 63 small block conversion Jeeze, Captain. Why couldn't I have found you guys when I needed a trans and a hood. Of course I joined after I bought those items. __________________ 1963 GMC SWB Fleetside in Sunburst Orange Metallic 305E V6 w/ Plaid VC, Powerglide, BOSS 313 20" Chrome Wheels, Kumho Ecsta STX 275/45/R20's, Alpine/Clarion System, Dynomax Exhaust Old custom classic trucks have soul. Their dashboards aren't plastic, and they've survived both the best and worst of what the 20th century had to offer. For the owners of these trucks, it's often the same story. Through both good and bad times they persevered, until one day they could turn the key and roll up in a customized truck everyone with good taste would admire. – Custom Classic Trucks

06-15-2009, 07:00 AM	#7
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	Re: 63 small block conversion awsome good to know captn, whats cost like for the mounts and the bell housing? i have also been toying with doing a turbo350/400 wich ever i can find were im shooting for a daily driver that may be the way to go anyway

06-16-2009, 12:00 AM	#8
Captainfab 60-66 Nut Join Date: Mar 2007 Location: Coeur d'Alene, Idaho Posts: 23,246	Re: 63 small block conversion PM sent. __________________ Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE

06-16-2009, 11:49 AM	#9
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	Re: 63 small block conversion Ok so captain now has me wondering what year of truck I actually have, besides the clutch linkage what are some differences I can look for to differentiate between 60-62 and 63 wich is what the vehicle is titled as

06-16-2009, 12:24 PM	#10
MacAttack 283 Drama Queen Join Date: Dec 2004 Location: Surf City, CA Posts: 2,435	Re: 63 small block conversion Welcome owen13 - this is what this site's all about. Plenty of help and, of course - demands for pics of your rig. (Friendly Warning) Mac. __________________ For about 12 years of my adult life I had a severe speech impediment. My ex-wife never let me get a word in edgewise.

06-16-2009, 12:43 PM	#11
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,687	Re: 63 small block conversion 1963 is the only year truck that has coil front suspension and a wrap-a-round windshield. That should help you determine what year you have..... Oh, and __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(winter unit)https://67-72chevytrucks.com/vboard/...25#post8900725

06-16-2009, 05:09 PM	#12
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	Re: 63 small block conversion haha thanks for the warm invite guys , i have not dug out the truck quit literaly but here are the pics that i do have of it, it does have coil fronts and the wrap around windshield but it does also have the combo brake/clutch master which i have heard was only on the 60-62 model years. could this be because it is a custom? ill get some better pics once i get it out of its hole Attached Images

06-16-2009, 05:40 PM	#13
Joemomma1 Registered User Join Date: Mar 2009 Location: CA Posts: 813	Re: 63 small block conversion Nice, a custom. I pulled the same 305 setup in favor of a 350/th350 and am happy with it. Its nice to be all original but to me it was not practical keeping that engine/tranny combo for a daily driver.

06-16-2009, 05:44 PM	#14
owen13 Registered User Join Date: Jun 2009 Location: sl,ut Posts: 8	Re: 63 small block conversion yeah i am in the same boat, i had a 61 3/4 ton with that engine trans combo and know how poorly they do as a daily driver that's why i am looking to do the change over

06-16-2009, 11:01 PM	#15
Captainfab 60-66 Nut Join Date: Mar 2007 Location: Coeur d'Alene, Idaho Posts: 23,246	Re: 63 small block conversion It's quite possible that it is an early '63 and they were just using up the previous years parts. That or is it possible that the hydraulic clutch was standard for the '63 GMC's ? Most of my experience has been with Chevy's..... __________________ Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE



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06-16-2009, 11:04 PM	#16
TwiggyTheDrummer Keep It Simple Stupid.. Nope.. Join Date: Jan 2009 Location: Live Oak, FL Posts: 665	Re: 63 small block conversion Standard clutch. Same thing on mine. __________________ 1963 GMC SWB Fleetside in Sunburst Orange Metallic 305E V6 w/ Plaid VC, Powerglide, BOSS 313 20" Chrome Wheels, Kumho Ecsta STX 275/45/R20's, Alpine/Clarion System, Dynomax Exhaust Old custom classic trucks have soul. Their dashboards aren't plastic, and they've survived both the best and worst of what the 20th century had to offer. For the owners of these trucks, it's often the same story. Through both good and bad times they persevered, until one day they could turn the key and roll up in a customized truck everyone with good taste would admire. – Custom Classic Trucks

Register or Log In To remove these advertisements.