Hi all,

I've got a 97 Ram 1500 5.9L that I'm looking to replace the cylinder heads on. I can get a screaming deal on some rebuilt 5.2L heads ($100 for both through a friend) from a 97 Jeep and was wondering if they would work ok. Are there any differences between them?

The mechanic I'm going to use called his machine shop and they said that they are the same except one time there was an issue with where the pushrods came through??? Not sure what he's talking about there.

The motor has 155k miles on it and it's running rough with the check engine light on (missfiring cyl 5 IIRC). Compression is good but there's a leak down on a couple of the valves. My mechanic also mentioned that putting new heads on the old bottom end could cause the rings to blow out because of added compression...anyone have experience with that?

If it wasn't apparent, I'm pretty much a newbie to Dodge trucks and American pushrod motors in general.

Thanks,
-Marcus

 

Welcome to DF!

The new heads on an old block thing doesnt fly with me... either the rings are sealed or they're not. I'd stay away from the stock mangum heads, re-built or not, they suck. there is a heavy duty casting that is out there (Hughes engines has them) that are reasonable when built with the stock type of components.

the heads are the same for a 318 and a 360.

HTH

 

Here is the solution to all of your problems, and I know your gonna dig this![sm=coolness.gif]

1. Go to a car dealership and lease yourself a brand new Dodge Ram 1500 with a Hemi and a corporate 9.25 rear end...
2. Pull the motor out of your old truck, and now, rebuild it from the bottom up to factory specifications or to higher Mopar standards as you see fit.
3. Finish working on your truck.
4. Have a buddy steal your truck, strip it for everything it's worth, and then push it off a cliff or something like that.
4. Report it stolen with a big smile, and maybe some spare parts like the disc brakes off the newer model, etc. etc. etc.

I hear things like headlights, bumpers, grills, and such go for quite a few pesos these days.

 

O yeah, may as well order that new dodge with some gears and a locker in the rear just for ****z and giggles

 

I'm pretty sure the 360 heads have bigger volume, since they give you lower compression if you put them on a 318. Not sure if 5.2 heads will work on a 5.9 though. They should give you higher compression if anything, and probably hold back your engines breathing.

 

nope. post 1994 magnum cylinder heads are the same on 5.2/5.9 engines.

combustion chamber size is 62 cc. (compression will not change with a head swap)

170 cc intake runner

1.92 1.65 valves

 

I'm dumb. Sorry, you are right.

 

I was just doing some reading on the main bearing journal sizes of these magnum engines, and according to Dodgeram.org they are not the same. Mains on a 360 are a few mm. larger than those on a 318, thus some of the stroker kits from Hughesengine.com will not work for the 318.

However when it comes to the heads and cam on these motors, there are some differences.

The valves on a 318/5.2 are minutely larger than those on a 360/5.9...

318/5.2 magnum engine Intake valve size = 1.916 inch (48.666mm), Exhaust Valve size = 1.624 inch (41.250 mm)

360/5.9 magnum engine Intake valve size = 1.88 inch (47.752mm), Exhaust valve size= 1.617 inch (41.072 mm)

Cams, valve lifts,valve timing, and valve legnth are slightly different.

318 had 0.432" valve lift

5.2L Valve Timing Specs

1994-1995 1996 1997 1998 1999-2001
Exhaust Closes (deg ATC) 21 21
Exhaust opens (deg BBC) 60 60
Exhaust duration (deg) 264 264
Intake opens (deg BTC) 10 10
Intake Closes (deg ABC) 61 61
Intake duration (deg) 250 250
Valve Overlap (deg) 31 31
Compression Ratio 9.1 9.1


From DiRT postings by Tom Lawrence and Henry LaViers.

360 had 0.410" valve lift

5.9L Valve Timing Specs

1994-1995 1996 1997 1998 1999-2001
Exhaust Closes (deg ATC) 23 33
Exhaust opens (deg BBC) 61 56
Exhaust duration (deg) 264 269
Intake Closes (deg ABC) 80 62
Intake opens (deg BTC) 13 7
Intake duration (deg) 274 249
Valve Overlap (deg) 36.5 41
Compression Ratio 9.1 9.1




From DiRT postings by Tom Lawrence and Henry LaViers, and factory service manuals.

Lots of info on the old magnum motors on that site. Once again, Dodgeram.org

 

Hmmmm.... Copying and pasting that table from the site didn't come out too well.

If anyone would like to see the original tables just click here on these links.

For the 5.2, click here... http://dodgeram.org/tech/gas/specs/valve-5_2.htm

For the 5.9, click here... http://dodgeram.org/tech/gas/specs/valve-5_9.htm

 

The 5.2 and 5.9 magnum cylinder heads are the same
but there are at least three different foundary casting mark numbers
on cylinder heads of different years.