Thanks! Off hand, do you remember the A-500’s ratios?
Which motor for trouble free cruising including highway miles
- Thread starter Willy Moose
- Start date
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junkyardhero
Well-Known Member
i have seen the following published:
2.67, 1.54, 1.00, .69
2.70, 1.54, 1.00, .69
2.74, 1.54, 1.00, .69
the 2nd, 3rd & OD all remain consistent which leads me to believe that the differences in 1st are for V6 equipped trucks, or perhaps different years.
hth
michiganpat
Well-Known Member
42RH is the "new nomenclature" name for the A500, 46RH=A518
michiganpat
Well-Known Member
AFAIK, I've never seen multiple ratios for the 42RH/42RE/A500, I've only seen 2.74/1.54/1/.69. in fact, I've only seen 2.45/1.45 1st/2nd or 2.74/1.54 1st/2nd for any 904 based tranny
junkyardhero
Well-Known Member
i'm only reporting what i've seen listed online from what i would consider reputable sources. i am not a transmission repair man, nor have i played one in film or on television.
Thanks. The 42 & 46 numbers never seem to sink in my head permanently.
And thats a darn good thing because they would just call you the trannyman which has its drawbacks with a certain crowd.
Honestly, that was a funny reply.
But I bet you slept at a Best Western!
DionR
Well-Known Member
I think this is incorrect knowledge based on Mopar publishing the LA 360 cam specs (among other misinformation) when the 5.9 was released in '93. Another example of this is the valve size and the idea that 5.2 heads had bigger valves (1.92 vs. 1.88) when in reality the Magnum head never varied and were used on both the 5.2 and 5.9 in the same configuration. I had my 2000 5.9 cam run through a Cam Doctor before Bullet reground it and (as I recall) it was bigger than the published numbers I found for stock 5.2 cams.
That said, I wouldn't put a stock cam in a 5.9 regardless of what it came out of. They barely have lobes and at the very least need to be reground with some duration and lift. Might as well put a broomstick in it if you use a stock Magnum cam.
Just a mild upgrade in the camshaft duration with a minor extra bit of lift is all that the 5.2 or 5.9 need to make for a nice street engine for running around town or the Hwy.
Same old school principles apply & still work.
Same old school principles apply & still work.
harrisonm
Well-Known Member
michiganpat
Well-Known Member
IIRC stock magnum 5.9 cams were only about .400 lift, but the 318 was more like .450. the 5.9 might have had a little more duration...I think the 318 was only like 250 adv duration on the intake side.....gave away my '97 ram FSM to my neighbor down the street who inherited a '99 ram from his dad, so I can't look it up anymore.
DionR
Well-Known Member
Here is what @YY1 posted for numbers.
5.2 Magnum Hydraulic Roller 432/432 251/264 113CL
5.9 Magnum Hydraulic Roller 410/417 249/269 109CL
Here are the numbers I got from having a 2000 Ram 5.9 cam run through the Cam Doctor at Bullet Cams:
Duration @ 0.050: I/E 189*/194*
Lobe separation angle: 111*
Lift @ cam: I/E 0.273"/0.278"
Valve lift w/ 1.6 rockers: I/E 0.437”/0.445”
Not sure on the advertised duration numbers, but my 5.9 cam had more lift than both the 5.2 and the published 5.9 numbers.
One interesting point that YY1 made someplace (as I recall) is that the published valve lift numbers for the 5.9 match the cam lift numbers from my cam if you use a 1.5 rocker ratio. So it is possible that info like that was just done wrong, but the rest of it is correct. No sure, just pointing it out.
If we assume the advertised duration is correct on the numbers from YY1, the 5.9 cam is a couple of degrees smaller on the intake but larger on the exhaust and my lift number say both are taller on the 5.9 cam.
Based on that, I don't believe the 5.2 cam is better. Frankly, I think both are so small it wouldn't make much difference either way.
thesiren74
Well-Known Member
Every 5.9l magnum I've had has been over 200,000 miles on them and only got rid of them because body panels were flapping in the wind.
It's the most reliable choice.Why did I KNOW you would make that suggestion.
It is a good idea though.
harrisonm
Well-Known Member
Serious question! Is a /6 more reliable than a 318 barrel? I know the slants are amazing motors, but I've had several cars with a 318 2 barrel, and I never had a problem? I would be interested in your thoughts.
No.
junkyardhero
Well-Known Member
i will posit that while both can take criminal amounts of abuse the mighty leaning tower of power can and will endure shameful levels of neglect and keep right on chugging along.
but maintained like for like, i'd say maybe the slant noses out our most beloved small block only on the condition that it doesn't really make enough power to hurt itself. it's a feature, not a bug.
I think they are about even. But the slant is cooler.
lol Probably accurate. But that was the whole point of the design. I can hear the engineers' round table conversation......."We want a dead reliable engine. A slug. One that will last forever with no chance of self destruction under normal use. You know, a slug" lol
That's what non slant guys will never understand. Therein lies the beauty. lol
Definitely find a roller cam block, whether LA or Magnum.
If you want to get buy on the cheap and reuse pistons, magnum is the choice as they have much better compression ratio. They also tend to have minimal cylinder wear thanks to the fuel injection that makes it more likely you can get by with a hone and rering job.
Magnum stock heads are an issue and likely cracked between the seats. 90 plus percent of the time it is a non issue and they will perform fine on a driver engine. That said, the last set of LA 360 heads I needed I had to go through 4 sets to find 2 that weren't cracked.
Transmission choice is simple. Get a 46rh. Simple retrofit and it makes highway cruising a pleasure.
I had a 92 Dakota with 5.2, 518, and an 8 1/4 3.55 rear. Gave great service and would knock down 20mpg on the highway. Tonneau cover, electric fans, and 31 inch tires all helped with the mpg, as did the 8 1/4 rear. If you don't beat on it, and don't plan to tow, it is a fine rear. I had a 90 dakota 8 1/4 rear that had the 5 x 4.5 lug pattern. Direct swap into the newer 92 8 1/4 to get away from the 6 lug pattern. Earlier dakota 5 lug rotors were also a bolt on deal.
Hope this helps and look forward to updates on your progress with your hot rod.
Does your setup have a parking brake?
Just wouldn't be right around here without you chiming in with the slant six post.
I gotta counter some of the "put a 360 in it" nonsense. LOLJust wouldn't be right around here without you chiming in with the slant six post.
junkyardhero
Well-Known Member
*to the tune of: screw y'all i'm going to texas*
imma put a red ram hee-mee in it!
I completely agree with the magnum recommendation. All of the LA series now....even the later roller blocks now are OLD and most will require a lot of machine work. You can still find Magnums in decent shape. For now.
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