News: Putting FUN and FRIENDLINESS, FIRST into owning and learning about AMC small bodied cars, primarily Eagles, Spirits and Concords as well as vehicles built in AMC's Mexican subsidiary, VAM.

The AMC Eaglepedia can now be accessed using the buttons found below  This is a comprehensive ever growing archive of information, tips, diagrams, manuals, etc. for the AMC Eagle and other small bodied AMC cars. 

Also a button is now available for our Face Book Group page.

Welcome to the AMC Eagles Nest.  A new site under "old" management -- so welcome to your new home for everything related to AMC Eagles, Spirits and Concords along with opportunities to interact with other AMC'ers.  This site will soon be evolving to look different than it has and we will be incorporating new features we hope you will find useful, entertaining and expand your AMC horizons.

You can now promote your topics at your favorite social media site by clicking on the appropriate icon (top upper right of the page) while viewing the topic you wish to promote.


  • June 26, 2024, 04:54:38 AM

Login with username, password and session length

« previous next »
Pages: [1] 2  All   Go Down

Author Topic: Low end Power?  (Read 5748 times)

0 Members and 3 Guests are viewing this topic.

Offline AMCLOVER258

  • Eagle DL
  • ***
  • Posts: 249
  • Thumbs Up 4
Low end Power?
« on: June 20, 2014, 03:30:01 PM »
So i am New to the Eagle family. I have an 82 $ door with the 258. On the highway the car runs amazing i can keep steady at 85 90 with no problem however i have 0 take off... that car will not even Chirp a tire. is that normal lol?
Logged

Offline eaglefreek

  • Moderators
  • AMC Eagles Den Addicted
  • *****
  • Posts: 4011
  • Thumbs Up 209
Re: Low end Power?
« Reply #1 on: June 20, 2014, 04:10:10 PM »
Quote from: AMCLOVER258 on June 20, 2014, 03:30:01 PM
So i am New to the Eagle family. I have an 82 $ door with the 258. On the highway the car runs amazing i can keep steady at 85 90 with no problem however i have 0 take off... that car will not even Chirp a tire. is that normal lol?
Yes, it is quite normal. I assume you have and auto transmission and would bet you have 2.35 gearing in your axles which don't help at low speeds. Also, the stock 258 camshaft is too "mild".
Logged
1986 AMC Eagle Wagon 4.2L/4.0L head, AW4,NP242, Chrysler 8.25" rear.
1981 AMC Eagle Wagon As Seen On TV  Lost In Transmission


 

"I know he'd be a poorer man, if he never saw an eagle fly,
Rocky mountain high"  John Denver
Click for Fayetteville,TN Forecast" border="0" height="100" width="150

Offline AMCLOVER258

  • Eagle DL
  • ***
  • Posts: 249
  • Thumbs Up 4
Re: Low end Power?
« Reply #2 on: June 20, 2014, 06:20:49 PM »
 >:( Darn.. So a new cam and all that lovely head stuff would help get'r moving a little more?
Logged

Offline Mernsy

  • Eagle DL
  • ***
  • Posts: 248
  • Thumbs Up 13
Re: Low end Power?
« Reply #3 on: June 20, 2014, 06:25:50 PM »
Is your tranny shifting gears early by any chance?
Logged

Offline AMCLOVER258

  • Eagle DL
  • ***
  • Posts: 249
  • Thumbs Up 4
Re: Low end Power?
« Reply #4 on: June 20, 2014, 07:47:27 PM »
NO, it is weak though, it doesn't shift very smoothly.. like even if i put it in 1st gear( its a 3 spd auto with the OD) it takes off a little better but wont turn those tires!
Logged

Offline Mernsy

  • Eagle DL
  • ***
  • Posts: 248
  • Thumbs Up 13
Re: Low end Power?
« Reply #5 on: June 20, 2014, 08:23:26 PM »
The 4.0l head and cam swap will turn them.
Logged

Offline carnuck

  • Having a 727 means never re-doing the trans again
  • AMC Eagles Den Addicted
  • ********
  • Posts: 3451
  • Thumbs Up 89
  • Near Seattle
    • Virtual Jeep
Re: Low end Power?
« Reply #6 on: June 21, 2014, 11:47:43 PM »
No overdrive unless it was swapped in. Just a lockup converter. Swapping to 2.72 ratio will help you a lot and STILL give good freeway performance. Taller than stock tires kill the power too, because it actually CHANGES the effective gear ratio. Low profile tires will give you take off power again.
Logged
AMC/Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental!

Offline AMCLOVER258

  • Eagle DL
  • ***
  • Posts: 249
  • Thumbs Up 4
Re: Low end Power?
« Reply #7 on: June 23, 2014, 04:35:24 PM »
So 2.72 Ring and pinion and find someone to put it in.. i dont think i could go Low prof's that would look rediculous lol
Logged

Offline Mernsy

  • Eagle DL
  • ***
  • Posts: 248
  • Thumbs Up 13
Re: Low end Power?
« Reply #8 on: June 23, 2014, 04:57:34 PM »
Quote from: AMCLOVER258 on June 23, 2014, 04:35:24 PM
So 2.72 Ring and pinion and find someone to put it in..

You have to change gears in both diffs.
Logged

Offline BenM

  • AMC Eagles Den Addicted
  • ********
  • Posts: 1512
  • Thumbs Up 74
  • Pittsburgh, PA
Re: Low end Power?
« Reply #9 on: June 23, 2014, 06:00:58 PM »
With the 2.35 gears it's like having a four-speed transmission that will only start in second. The lockup will definitely feel like another gear, it's more noticeable with 2.35 gears.

Back in the old days you really had to suffer, I have a Pontiac with an ST-300 (another GM two-speed transmission mostly unrelated to the famous Powerglide) and a rear around 2.9. It is positively glacial until you got the thing up over 40, even with a V8. I guess the point of that is even with the wide-ratio automatic you should have it could be worse.  ;)

With the '82 you probably have a better chance of being able to swap the front gears for a 2.72 set, and the 2.72 with the wide-ratio lockup transmission is a pretty good compromise, 3.08s in a sedan or wagon are a good choice as well, it depends on if you do more highway miles or not. There are a couple of threads here that discuss the things you have to look for to see if your front end can be changed, not all 2.35 gears can.

Play around at http://www.grimmjeeper.com/gears.html and you'll see the RPM to speed. The "Dodge TF 999" has the correct wide-ratio gears. To see the difference with the narrow transmission used in 80 and 81, first is 2.45 and second is 1.45. For fun, my two speed ST-300 is 1.77 in low. These are all 1:1 in high, but they slip and act like a lower gear if they don't lock up, the calculator does a nice job of compensating for that as well.
Logged
NSS#47184

1987 AMC Eagle Sedan -- 1976 Pacer Coupe -- 1968 Pontiac Tempest Custom S -- 1940 Mercury (& a 2002 Jetta Turbodiesel, 5 spd., the Wife's Daily Driver)

Offline Eagle Groupie

  • Eagle
  • **
  • Posts: 54
  • Thumbs Up 2
  • Allentown, PA
Re: Low end Power?
« Reply #10 on: June 23, 2014, 07:03:03 PM »
Quote from: AMCLOVER258 on June 23, 2014, 04:35:24 PM
i dont think i could go Low prof's that would look rediculous lol

Time for some Photoshop! :)
Logged

Offline carnuck

  • Having a 727 means never re-doing the trans again
  • AMC Eagles Den Addicted
  • ********
  • Posts: 3451
  • Thumbs Up 89
  • Near Seattle
    • Virtual Jeep
Re: Low end Power?
« Reply #11 on: June 24, 2014, 01:13:04 AM »
If you plan taller tires, 3.08 is far better and leaves room for O/D down the road. I'm surprised no-one has taken me up on the  2.72 vacuum front diff (70K miles and rarely in 4x4) and Model 20 with 2.72 gears for $100 for the pair.
Logged
AMC/Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental!

Offline Baskinator

  • Eagle Limited
  • *****
  • Posts: 526
  • Thumbs Up 31
  • Limerick, PA
Re: Low end Power?
« Reply #12 on: September 15, 2014, 08:47:20 AM »
Quote from: carnuck on June 24, 2014, 01:13:04 AM
I'm surprised no-one has taken me up on the  2.72 vacuum front diff (70K miles and rarely in 4x4) and Model 20 with 2.72 gears for $100 for the pair.

I probably would if I wasn't on the opposite coast :/
« Last Edit: September 15, 2014, 08:47:51 AM by Baskinator »
Logged
1982 AMC Eagle SX/4 (Work In Progress)

Photobucket Album: http://s1237.photobucket.com/albums/ff479/Baskinator/

Offline carnuck

  • Having a 727 means never re-doing the trans again
  • AMC Eagles Den Addicted
  • ********
  • Posts: 3451
  • Thumbs Up 89
  • Near Seattle
    • Virtual Jeep
Re: Low end Power?
« Reply #13 on: September 15, 2014, 12:52:39 PM »
That's always the way! I know of a wagon for parts in Spokane, WA that will be crusher bound (if not already done)
Logged
AMC/Jeep gauges are for amusement only. Any correlation between them and reality is purely coincidental!

Offline IRON HORSE

  • Eagle DL
  • ***
  • Posts: 191
  • Thumbs Up 47
Re: Low end Power?
« Reply #14 on: September 15, 2014, 05:06:04 PM »
    Hello, Is your vacuum advance working ??? if it's not working you won't have power during accleration, but will cruse OK. Another thing to check is the kickdown linkage from throttle to transmission. This boosts the trans pressure when you step on the gas, and lowers the pressure when your stopped and in gear. If this linkage fails in the low pressure position the trans will slip and eventually fail.  Just my two cents .... Later, Iron Horse  :o
Logged
Pages: [1] 2  All   Go Up
« previous next »
 

SMF spam blocked by CleanTalk