6 cyl. Auto changeover - The 1947 - Present Chevrolet & GMC Truck Message Board Network

*1972Ryan* · 12-18-2007, 05:35 AM

I'm hoping someone can help me. I'm wanting to change my three on the tree over to an automatic. What shaft length 350 turbo is needed? My wife cant drive a stick and its her truck. She's always costing more money. I was hoping it would be motivation for here to learn......boy did that backfire!!!!!!!!!!

bad6772 · 12-18-2007, 06:43 AM

yeah id like to know this also....although i have a weird 18 inch long trans and not a 21??

*1972Ryan* · 12-18-2007, 12:14 PM

ttt

caja_larga · 12-18-2007, 12:50 PM

there are three lenths.. Ido not know the measurement but it is the middle. I just had one build and I am doing this conversion soon. I will get pictures and measurements.

**Tim Christian** · 12-18-2007, 02:33 PM

On this change over if you are leaving the 6-cylinder All you need is a 350 turbo with a 6 inch tailshaft. It is the exact same size as your 3-speed bolted to your bellhousing. You will be able to use the driveshaft you already have. Tim

bad6772 · 12-18-2007, 03:57 PM

hey tim what size trans???the 21 or 18 inchers...????????

**Tim Christian** · 12-19-2007, 12:52 AM

I have not measured just the trans by itself but I guess it would be the 18 in. They made 3 diffrent turbo 350's a 6in, 9in, and 12in tailshaft. You would need the shortest one if you are planning on using the same drive shaft with the 6-cylinder. Now if you are converting to a V-8 it is a diffrent ballgame.

bad6772 · 12-19-2007, 01:54 AM

thanks tim.....any guess on how this 6cyl and auto will run? i know the 350 will take some extra ponies....but i dont know how much????

crazy longhorn · 12-19-2007, 04:36 AM

On your 67, you will need to replace the slipyolk & shorten the front D shaft to do the swap. I agree with using the short (6" tail" 350 T), & thats a direct swap on the later trucks with the saginaw trans(7 bolt side cover). Your shortie 3 spd is a Muncie(iD by 4 bolt side cover). You can also use a D shaft from a 69-72, 6 cyl 3 spd truck that has the same wheel base as your truck. Best of luck,crazyL

*1972Ryan* · 01-04-2008, 05:25 AM

What is needed as far as the linkage is concerned? Is it different for a six with an automatic?

Blue71LWB · 01-04-2008, 05:57 AM

Ryan,
If you are running a stock intake/carb set-up you will need to fab or source a kickdown bracket. I would assume these would be tough to come by , as most 6 cyl had the manual trans.

(I copied this pic from here http://67-72chevytrucks.com/vboard/s...d.php?t=271500
Zac

brianthelion02 · 01-04-2008, 02:29 PM

Those brackets are very hard to find,i sure do need one!!!!!!

Quote:

Originally Posted by Blue71LWB

Ryan,
If you are running a stock intake/carb set-up you will need to fab or source a kickdown bracket. I would assume these would be tough to come by , as most 6 cyl had the manual trans.

(I copied this pic from here http://67-72chevytrucks.com/vboard/s...d.php?t=271500
Zac

**Tim Christian** · 01-04-2008, 06:25 AM

Hey Ryan I have the correct driveshaft and linkage for the auto. Also have a van tilt column that will work on the 6 cylinder.

*1972Ryan* · 01-04-2008, 07:16 AM

I am running an Clifford Intake and Holley #4548-s carb on it and will add a header as soon as I can afford one. I will also be adding A/C when I can find a template for the holes to be cut. I'm doing the truck for my wife and want it to be driver friendly for her ability....LOL

*1972Ryan* · 01-06-2008, 03:29 AM

ttt........anyone know where Brian and I can find the brackets?

lutherb69 · 01-06-2008, 10:39 AM

Hello I'm in the same boat I have a 68 Surburban with MT on the floor and want it to be AT would the same go for me if I have a 2 part driveshaft? Also want to change gears at the wheel. Thanks for the time.

sea chief · 01-06-2008, 11:55 PM

I would like to do this too. My big question is what about the flex plate. Will a v-8 flex plate work?

12-18-2007, 05:35 AM	#1
1972Ryan Account Suspended Join Date: Mar 2006 Location: Weaverville, NC Posts: 718	6 cyl. Auto changeover I'm hoping someone can help me. I'm wanting to change my three on the tree over to an automatic. What shaft length 350 turbo is needed? My wife cant drive a stick and its her truck. She's always costing more money. I was hoping it would be motivation for here to learn......boy did that backfire!!!!!!!!!!

12-18-2007, 06:43 AM	#2
bad6772 Official Site Guitar Shredder Join Date: May 2006 Location: Oz Posts: 3,955	Re: 6 cyl. Auto changeover yeah id like to know this also....although i have a weird 18 inch long trans and not a 21??

12-18-2007, 12:14 PM	#3
1972Ryan Account Suspended Join Date: Mar 2006 Location: Weaverville, NC Posts: 718	Re: 6 cyl. Auto changeover ttt

12-18-2007, 02:33 PM	#5
Tim Christian Senior Member Join Date: Dec 1999 Location: TN/VA Posts: 6,388	Re: 6 cyl. Auto changeover On this change over if you are leaving the 6-cylinder All you need is a 350 turbo with a 6 inch tailshaft. It is the exact same size as your 3-speed bolted to your bellhousing. You will be able to use the driveshaft you already have. Tim

12-18-2007, 03:57 PM	#6
bad6772 Official Site Guitar Shredder Join Date: May 2006 Location: Oz Posts: 3,955	Re: 6 cyl. Auto changeover hey tim what size trans???the 21 or 18 inchers...????????

12-18-2007, 12:50 PM	#4
caja_larga Registered User Join Date: Oct 2007 Location: Tucson, Az Posts: 172	Re: 6 cyl. Auto changeover there are three lenths.. Ido not know the measurement but it is the middle. I just had one build and I am doing this conversion soon. I will get pictures and measurements.

12-19-2007, 12:52 AM	#7
Tim Christian Senior Member Join Date: Dec 1999 Location: TN/VA Posts: 6,388	Re: 6 cyl. Auto changeover I have not measured just the trans by itself but I guess it would be the 18 in. They made 3 diffrent turbo 350's a 6in, 9in, and 12in tailshaft. You would need the shortest one if you are planning on using the same drive shaft with the 6-cylinder. Now if you are converting to a V-8 it is a diffrent ballgame.

12-19-2007, 01:54 AM	#8
bad6772 Official Site Guitar Shredder Join Date: May 2006 Location: Oz Posts: 3,955	Re: 6 cyl. Auto changeover thanks tim.....any guess on how this 6cyl and auto will run? i know the 350 will take some extra ponies....but i dont know how much???? Last edited by bad6772; 12-19-2007 at 01:54 AM.

12-19-2007, 04:36 AM	#9
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,402	Re: 6 cyl. Auto changeover On your 67, you will need to replace the slipyolk & shorten the front D shaft to do the swap. I agree with using the short (6" tail" 350 T), & thats a direct swap on the later trucks with the saginaw trans(7 bolt side cover). Your shortie 3 spd is a Muncie(iD by 4 bolt side cover). You can also use a D shaft from a 69-72, 6 cyl 3 spd truck that has the same wheel base as your truck. Best of luck,crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

01-04-2008, 05:25 AM	#10
1972Ryan Account Suspended Join Date: Mar 2006 Location: Weaverville, NC Posts: 718	Re: 6 cyl. Auto changeover What is needed as far as the linkage is concerned? Is it different for a six with an automatic?

01-04-2008, 05:57 AM	#11
Blue71LWB Registered User Join Date: Nov 2006 Location: Alabama Posts: 120	Re: 6 cyl. Auto changeover Ryan, If you are running a stock intake/carb set-up you will need to fab or source a kickdown bracket. I would assume these would be tough to come by , as most 6 cyl had the manual trans. (I copied this pic from here http://67-72chevytrucks.com/vboard/s...d.php?t=271500 Zac Attached Images __________________ Working on my first 1,000 post. I'm sure I'll get there before this project is over . Last edited by Blue71LWB; 01-04-2008 at 06:00 AM.

01-04-2008, 06:25 AM	#13
Tim Christian Senior Member Join Date: Dec 1999 Location: TN/VA Posts: 6,388	Re: 6 cyl. Auto changeover Hey Ryan I have the correct driveshaft and linkage for the auto. Also have a van tilt column that will work on the 6 cylinder. Last edited by Tim Christian; 01-04-2008 at 06:25 AM.

01-04-2008, 07:16 AM	#14
1972Ryan Account Suspended Join Date: Mar 2006 Location: Weaverville, NC Posts: 718	Re: 6 cyl. Auto changeover I am running an Clifford Intake and Holley #4548-s carb on it and will add a header as soon as I can afford one. I will also be adding A/C when I can find a template for the holes to be cut. I'm doing the truck for my wife and want it to be driver friendly for her ability....LOL

01-06-2008, 03:29 AM	#15
1972Ryan Account Suspended Join Date: Mar 2006 Location: Weaverville, NC Posts: 718	Re: 6 cyl. Auto changeover ttt........anyone know where Brian and I can find the brackets?

01-06-2008, 10:39 AM	#16
lutherb69 Registered User Join Date: Oct 2005 Location: Langley AFB, Va (Army) Posts: 124	Re: 6 cyl. Auto changeover Hello I'm in the same boat I have a 68 Surburban with MT on the floor and want it to be AT would the same go for me if I have a 2 part driveshaft? Also want to change gears at the wheel. Thanks for the time.



Register or Log In To remove these advertisements.

01-06-2008, 11:55 PM	#17
sea chief Registered User Join Date: Jan 2007 Location: vermont Posts: 27	Re: 6 cyl. Auto changeover I would like to do this too. My big question is what about the flex plate. Will a v-8 flex plate work? __________________ 1967 K-20, 1969 K-20, 1970 C-30 dump,1971 K-20 1972 K-20, 1972 C-10, 1968 Grandprix John Deere 350c Dozer, 3414 International backhoe 1972 International 1600 Flatbed

Register or Log In To remove these advertisements.