TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC 6 Cylinder Engine Repair and Modifications
  New Posts New Posts RSS Feed - Lighter weight 258 ?? question
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

Lighter weight 258 ?? question
 Post Reply Post Reply Page  123 5>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
Mr_AMC View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Sep/27/2010
Location: Charleston, SC
Status: Offline
Points: 125 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Mr_AMC Quote  Post ReplyReply Direct Link To This Post Topic: Lighter weight 258 ?? question
    Posted: Oct/29/2019 at 8:53am
What year did the lighter weight 258 come out, and how can you tell it from the heavier one? 

Back to Top
AMXRWB View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/25/2013
Location: Midwest
Status: Offline
Points: 1154 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AMXRWB Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 10:27am
Plastic valve cover,small head bolts.
Back to Top
73Gremlin401 View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Mar/02/2013
Location: Stmbt Sprgs CO
Status: Offline
Points: 955 		Post Options Post Options   Thanks (0) Thanks(0)   Quote 73Gremlin401 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 10:52am
1981 was the first year for the lightweight motor. 

73 Gremlin 401/5-spd.
77 Matador Wagon 360/727.
81 Jeep J10 LWB 360/4-spd
83 Concord DL 4-dr 258/auto
Back to Top
purple72Gremlin View Drop Down
AMC Addicted
AMC Addicted
Avatar
Charter Member

Joined: Jul/01/2007
Location: Illinois
Status: Offline
Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 4:41pm
And less counterweights on the crankshaft IIRC.
Back to Top
Heavy 488 View Drop Down
AMC Addicted
AMC Addicted


Joined: Apr/27/2019
Location: In the
Status: Offline
Points: 3557 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 7:09pm
Originally posted by purple72Gremlin purple72Gremlin wrote:

And less counterweights on the crankshaft IIRC.

I seem to recall 6 versus 12 counterweights.
Back to Top
purple72Gremlin View Drop Down
AMC Addicted
AMC Addicted
Avatar
Charter Member

Joined: Jul/01/2007
Location: Illinois
Status: Offline
Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 7:30pm
Originally posted by Heavy 488 Heavy 488 wrote:

Originally posted by purple72Gremlin purple72Gremlin wrote:

And less counterweights on the crankshaft IIRC.

I seem to recall 6 versus 12 counterweights.
yes. I remember reading this way back in 1980-81. (Jeeps)
Back to Top
81eagle View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Apr/17/2018
Location: Wyoming
Status: Offline
Points: 65 		Post Options Post Options   Thanks (0) Thanks(0)   Quote 81eagle Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 7:37pm
Aluminum intake.
Back to Top
purple72Gremlin View Drop Down
AMC Addicted
AMC Addicted
Avatar
Charter Member

Joined: Jul/01/2007
Location: Illinois
Status: Offline
Points: 16614 		Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 7:41pm
And 1980 up blocks added the bosses for the eagle front differential brace......
Back to Top
tomj View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jan/27/2010
Location: earth
Status: Offline
Points: 7555 		Post Options Post Options   Thanks (0) Thanks(0)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Oct/29/2019 at 8:22pm
i had an 82 258, stuffed into a 70 Hornet. there's a nice aftermarket aluminum valve cover, definitely worth springing for. i had to notch it, and drill a hole inside th wiper box, and use an allen head bolt in the back and a long allen wrench through the hole to get to that back bolt.

the aluminum manifold is great, but watch out for corrosion. people dont maintain cooling systems very well.

1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5
http://www.ramblerLore.com
Back to Top
Mr_AMC View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Sep/27/2010
Location: Charleston, SC
Status: Offline
Points: 125 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Mr_AMC Quote  Post ReplyReply Direct Link To This Post Posted: Oct/30/2019 at 12:40pm
cool.. 
Thanks..
I used to know that, I think..  but just forgot.. LOL
Back to Top
 Post Reply Post Reply Page  123 5>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.188 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or