Help with my first engine build (5.9 Magnum)

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With 236@50 I’d bump the converter up also. 2500 will be ok. But 3000 would be better depending on the car weight and gear.
 
TT5.9mag said:
That’ll be a goodun (as RRR would say)
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Thanks, on the fence…236@050 & a 2500 Stall?
That’s why I was thinking Rhodes lifters on the intake only.
B body under 3600
 
With 355s and 3600lbs I wouldn’t put the 2500 in. With 411s and 2800 I would.
 
I’m on that side of the fence myself. To much cam IMO. I’m also NOT use to automatic transmissions. I’ve been hanging gear my whole life on the muscle rides.
 
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Converters are the magic mystery box of the car world. And they change the technology daily it seems. It’s almost like you can’t get too much converter in anything anymore. The last few I’ve bought the converter guys recommend way way more stall speed than I was thinking. A tight 5000 is now a street converter.
 
rumblefish360 said:
I’m on that side of the fence myself. To much cam IMO. I’m also NIT use to automatic transmissions. I’ve been hanging gear my whole life on the muscle rides.
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Probably too much cam if you don’t have above 9-1/2:1 comp for a street driver.
 
9.0-1 Not a big deal.
I’m waiting on Howard’s cam to restock.
 
I went with a PTC 9.5". Stalls around 3600. Definitely could have gone higher, but its a fun all around build.
 
Thanks for all the posts everyone, it’s more than I expected! Today I pulled the cleaned up the block up some, and got the the point where I could pull pistons.

At first glance the heads don’t appear to have any cracks, but I’ll be able to tell for sure after I remove the valves.

Rod bearings didn’t have any extreme wear, some copper showing on the topside bearing.

Cylinder walls aren’t perfect, but I think a dingle hone will clean them up well in preparation for new rings.

Tomorrow I’ll pull the cam and keep cleaning up the block in preparation for paint.

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rumblefish360 said:
To actually smooth down the ports and polish is a power looser. Don’t do it.
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Really? I didn’t know that, thanks for letting me know, I’ll happily step away from the Dremel. I was told by an old timer to polish the ports for better flow… you just saved me several hours of work!
 
Send the heads out to be magna-fluxed and pressure tested. 140K, its time for a proper valve job, guides checked and valve seals anyway. Check for warpage. Give them your valve springs and keepers and tell the what installed height you want. This is what they do. Heads are the heart of the motor.
 
ValleyRat said:
Really? I didn’t know that, thanks for letting me know, I’ll happily step away from the Dremel. I was told by an old timer to polish the ports for better flow… you just saved me several hours of work!
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It will increase flow but the fuel slides down the wall, not flow into the cylinders as expected. It’s an old timer trick that showed cfm on the bench but not power on the engine as expected.

Better off doing a bowl porting and a race prepped valve job. This will effect flow in the lift range of the valve lift with the cam you have. (Or getting.)
 
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ValleyRat said:
That's great information. I 've been told that the stock Magnum cams are very whimpy, but wasn't sure when I would have to start worrying about upgrading keepers and retainers with my choice of new cam. Its nice to know that I'll be able to use stock components (aside from valve springs).[/QUOTE
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rumblefish360 said:
It will increase flow but the fuel slides down the wall, not flow into the cylinders as expected. It’s an old timer trick that showed cfm on the bench but not power on the engine as expected.

Better off doing a bowl porting and a race prepped valve job. This will effect flow in the lift range of the valve lift with the cam you have. (Or getting.)
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Check out Hughes retainers if you run that cam. They are designer to provide extra clearance between the retainer and the valve guide. I didnt know about them until i had finished my magnim. My lift is 512 and I only have Less than 20 thousandths clearance between the retainer and valve guide. Also check out the 1110 ?? Valve Springs that are Good for 550 lift. Also check your piston to valve clearance with modeling clay. I believe that 80-100 thousandths is the " General rule." Dont clean the pistons mechanically or with strong chemicals. There is a friction reducing coating on the skirts.
 
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I have that spring, lock and retainer package myself.
Nice kit.
 
Just a quick update to show rod bearing wear, I can’t catch anything with my fingernail, but it looks like it’s a good time for fresh bearings.

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Well… looks like I can put cam bearings on the list of to do’s! Is it something I can do at home, or should I take it to a machine shop for the replacement? If I can I’d like to do it myself.

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Besides requiring a special tool, you can do it at home.
You’ll need one of these. It’s a cam bearing installation tool, mine is a kit. I’d purchase two sets of bearings if you have never done it before. It’s inky tricky the first time you use it.

I stalling the bearing is a one shot deal, so, if you don’t clock the bearing hole correctly or go to far hammering it I , the bearing is pretty much done because there a press fit.
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Have you considered grabbing a fresh set of hyperutectic pistons/rings to bump the compression ratio and improve the ring seal/longevity.

Don't hold you breath on grabbing some Eddie heads, as they are not flowing through the supply chain yet. Look on Hughes web site for new cast iron heads with better flow.

If you were going to EFI, there are some good tricks to improve the upper midrange power on that keg manifold. Those manifolds are unbeatable at low rpm power.
 
ValleyRat said:
Well… looks like I can put cam bearings on the list of to do’s! Is it something I can do at home, or should I take it to a machine shop for the replacement? If I can I’d like to do it myself.

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Glad you looked at em. You can do them yourself if you like a challenge. Once you do 4 or 5 sets of cam bearings they are simple. The first time you do it, it’s a bit nerve racking. But like anything else it’s a good skill to have. Don’t even attempt it without the right tool.
 
I know nothing about magnum heads, 1.64 installed height with a .506 lift? Are the seal bosses shorter on magnums than LA’s?
 
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