The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-14-2012, 11:58 PM   #1
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Question 6-8 Questions

So the truck currently has a 250 ci sixer that has a rear main seal leaking like crazy and valves? that are making all kinds of noise, lacks power and is generally worn out.

Now I have been giving a free 305 v8, lucky me right, that was freashly rebuilt about 6 months ago.

I wanted a 350 but ill take a free 305.

So the question is what has to change/move in order to swap in the v8???

I have done a half dozen v8 to v8 swaps but never a sixer to a v8.

Go easy on me if this is a stupid simple swap.
86C10LWB is offline   Reply With Quote
Old 10-15-2012, 12:12 AM   #2
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

The inline 6 and v8 both wont fit in there....
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511

Last edited by INSIDIOUS '86; 10-15-2012 at 12:14 AM. Reason: Bacon that is always the reason
INSIDIOUS '86 is offline   Reply With Quote
Old 10-15-2012, 12:15 AM   #3
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

INSISIOUS '86 - Huh, I don't follow.
86C10LWB is offline   Reply With Quote
Old 10-15-2012, 12:51 AM   #4
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Ah thanks for fixing that...ya I think I might has an issue with a inline6/v8 in the same engine bay


I dont know how to edit my previous post
86C10LWB is offline   Reply With Quote
Old 10-15-2012, 01:55 AM   #5
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

I'm yankin your chain. If th v8 has all the pulleys alt and pwr steering it should all go in pretty straightforward I imagine.
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 10-15-2012, 12:34 PM   #6
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Gothcha INSIDIOUS '86,

Guess I should have been move clear with my question, Do the engine stands have to move forward of backward. This truck started life with a 250ci sixer and I'm wanting to swap in a FREE 305 v8. Are the engine stands in the same place for the trans mount to line up and for the drive shaft lenght not be effected?
86C10LWB is offline   Reply With Quote
Old 10-15-2012, 02:57 PM   #7
3r!c84
Badass
 
3r!c84's Avatar
 
Join Date: Jan 2009
Location: lox. fl
Posts: 4,586
Re: 6-8 Questions

HAHAHA insdious86 : Bacon that is always the reason
__________________
Think outside the box?
-84c10 (1stcar)→My Build
-00 Saturn 5spd

drop a gear and disappear!

1/4:13:90
3r!c84 is offline   Reply With Quote
Old 10-16-2012, 12:57 AM   #8
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

So I take it that

(1) nobody cares to answer the question

(2) nobody can answer the question

(3) it cant be done

Thanks alot for the help ya'll
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 01:39 AM   #9
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

The drive shaft lengths should be the same. Gm also drilled the frame for multiple mounting of the crossmember and the v8 just has to have the original clamshell mounts and it will drop in

Your radiator will prob be too small and the shroud may not be the right on for a v8. And some of the wiring may be needed to be re routed

1. Have a sense of humor. This isn't a very common swap and usually was done with previous owners

2. See if any threads in the search yield anything. It's possible there is a build thread or a DIY or FAQ for this swap

3. Get some pics in here!
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511

Last edited by INSIDIOUS '86; 10-16-2012 at 01:41 AM. Reason: Bacon can always be done. Once upon a time I was at a park and I was hungry I made bacon in the parking lot width a gas grill
INSIDIOUS '86 is offline   Reply With Quote
Old 10-16-2012, 01:44 AM   #10
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Thanks INSIDIOUS '86

I dont mean to be an ass

I did search most of what I found was for the pre 73 trucks

On the pre 73 it looked like some moved the motor stands and some didnt.

Ill grab some pictures of it in the day light, but be warned its ugly. Just how I like em
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 02:00 AM   #11
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

Well the chassis of 67-72 trucks are very very similar to ours so the only way to know for sure I would say is maybe go to a wrecking yard and find a v8 truck and take pics and measurements of the mounts and such. Preferably a truck with the engine inside and one without. Compare to your truck and make changes as necessary
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511

Last edited by INSIDIOUS '86; 10-16-2012 at 02:04 AM. Reason: This gas grill fit behind my seat which made it pretty handy. The bacon came from a mini Mart around the corner mmm bacon
INSIDIOUS '86 is offline   Reply With Quote
Old 10-16-2012, 02:04 AM   #12
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Thats something I hadn't thought about but a great idea INSIDIOUS '86.

Ill be real close to a large yard tomorrow afternoon so...
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 02:08 AM   #13
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

Glad to help. Haven't done this myself so just telling how I would try and tackle it
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511

Last edited by INSIDIOUS '86; 10-16-2012 at 02:11 AM. Reason: If your reading my edits then cook some bacon. Don't catch them on fire once my pancakes caught fire and I couldn't eat them
INSIDIOUS '86 is offline   Reply With Quote
Old 10-16-2012, 02:38 AM   #14
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Much appreciated
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 02:19 PM   #15
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Pictures as promised

Pictures as promised
Attached Images
     
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 02:21 PM   #16
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Sorry for the crappy phone pictures buts what ya'll get
Attached Images
  
86C10LWB is offline   Reply With Quote
Old 10-16-2012, 11:20 PM   #17
3r!c84
Badass
 
3r!c84's Avatar
 
Join Date: Jan 2009
Location: lox. fl
Posts: 4,586
Re: 6-8 Questions

haha need the snap-out of it . for my tool box at work. i work with some hard core snapon or no tools guys, they would get a kick out of it
__________________
Think outside the box?
-84c10 (1stcar)→My Build
-00 Saturn 5spd

drop a gear and disappear!

1/4:13:90
3r!c84 is offline   Reply With Quote
Old 10-17-2012, 12:41 AM   #18
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Quote:
Originally Posted by 3r!c84 View Post
haha need the snap-out of it . for my tool box at work. i work with some hard core snapon or no tools guys, they would get a kick out of it

Thanks 3r!c84, my Matco tool man, who is the man, hooked me up with that at no charge. He has a guy make em for him, sells out of em fast. My Snap On tool guy isn't very happy about the sticker. He actually stopped coming around about two weeks after I put the sticker on my truck.
86C10LWB is offline   Reply With Quote
Old 11-15-2012, 12:41 AM   #19
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Talking Its officially and V8

So I finally got the free V8 in and running.

All that needed to change was the towers on the cross member. Moved them up one hole. No drilling or cutting.

Pretty easy swap.

The motor I set in is a 69-72 307ci I think it has a small cam, dont know. Didn't tear it down. The heads, if there stock, are 1.72 intake 1.50 exhaust IIRC.

Straight pipped with some flowmasters, there coming off and a set of magnaflows are taking their place. Don't care for the flows drone.

Ill try and get some photos up tomorrow.
86C10LWB is offline   Reply With Quote
Old 11-15-2012, 03:40 PM   #20
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: 6-8 Questions

Good job! How's it run?
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 11-15-2012, 09:45 PM   #21
86C10LWB
Registered User
 
Join Date: Jun 2012
Location: texas
Posts: 26
Re: 6-8 Questions

Quote:
Originally Posted by INSIDIOUS '86 View Post
Good job! How's it run?
Posted via Mobile Device
The Edelbrock carb I have on it has a dead spot right off idle and another one about 55 mph so its kinda temperamental. It likes to pop when cold and will sometimes just die if I idle to long. Timing is set a 8*.

I really want a Demon 650 vacuum secondaries, but thats not a option right now. I really have to say I love the 307. It has great torque, and when the carb wants to work the throttle response it great.

I have a question tho, I have a oil pressure gauge and I hooked to the oil pressure sending unit on the back of the block by the distributor and the gauge reads 60+ psi all the time, any ideas?

Last edited by 86C10LWB; 11-15-2012 at 09:52 PM.
86C10LWB is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:09 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com