Choosing cam for 5.9 magnum

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318willrun said:
the only thing with sending a cam to have it reground, is you lose some of the center, which means longer push rods. Who has a nice selection of NEW cams that work with the factory valve train (rockers and push rods)? Upgrading springs is no big deal.
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I agree about losing some base circle.

For just a few bucks more Kenny at Oregon Cams has new cores on the shelf rather than grinding a core. That keeps the base circle the same size.
 
yellow rose said:
I agree about losing some base circle.

For just a few bucks more Kenny at Oregon Cams has new cores on the shelf rather than grinding a core. That keeps the base circle the same size.
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Same thing I dealt with at Oregon with Ken, so I know for sure this is fact.
I just don't remember what the new core price difference was, but a quick call would answer that.
Phone: (360) 256-7985
 
Marcohotrod said:
measure retainer to seal clearance, then add little more clearance for safety. I see the kb107 at the same weight as stock-no rebalancing needed.
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The KB 107's will require balancing.
 
j par said:
Hughes grinds cams?
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They send them out...to whom I don't know. But it wasn't a shelf cam... I needed more duration. Iirc we went with 228 degrees at .050... somewhat limited in what we could do with a regrind.
 
318willrun said:
the only thing with sending a cam to have it reground, is you lose some of the center, which means longer push rods. Who has a nice selection of NEW cams that work with the factory valve train (rockers and push rods)? Upgrading springs is no big deal.
Click to expand...
But you could have the same deal if you zero deck the block and/or surface the heads.

Whatever the PO does he should be certain he has a cam ground for a .904 lifter... most of those shelf Comps are not.
 
Krooser said:
But you could have the same deal if you zero deck the block and/or surface the heads.

Whatever the PO does he should be certain he has a cam ground for a .904 lifter... most of those shelf Comps are not.
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Well, I've more than once cut heads .040 and never had a pushrod length issue. But, I really would think with ALL the magnum swaps happening these days, there would be the same amount of choices for "off the shelf" cams that work with stock push rods/rockers as the LA engines. Too bad there isn't....
 
Krooser said:
They send them out...to whom I don't know. But it wasn't a shelf cam... I needed more duration. Iirc we went with 228 degrees at .050... somewhat limited in what we could do with a regrind.
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Soooo, you send your cam to someone who sends it to someone? That doesn't sound very economical?
 
I am not sold on reground cams unless you absolutely are having a hard time finding a new one for an odd application. My buddy just got the 5.9 in his 01 ram sorted out after a Hughes regrind failed. It flaked out bad on the ramps and base circle where the material was mostly removed, the lobes actually looked fine on top. He was made right and upgraded to the next biggest on a new core. So far so good. That truck has the Hughes airgap, big gulp throttle body, the matching Hughes springs/retainers/locks, and now eq heads since it had one end cylinder on each head Crack between the seats.
 
I'm planning on a new cam. I spoke with hughes and planned on getting the cam from them since the heads have their springs. I've read around and the KB107's Have conflicting info on compression ratio. Hughes said it'll be a race gas 11:1 compression. I hope it's nothing close to that!

I dropped the block and crank off last week at the machine shop. It's getting bored .030 over, new brass core plugs, cam bearings, crank polished, and a general check up. I'll get it back and measure the deck height on THIS motor and see where I'm at.
 
I got my block last week and ordered bearings, gaskets, etc and assembled the short block today. The pistons all seem to measure around .004 in the hole. So nearly zero decked. Summit lists the KB107 pistons at +5cc piston volume. I'm kind of confused at how to enter that on summits compression calculator. Would it be entered as a +5cc for the dome volume? If so, that'll put me at a 10.7:1 with a .045 headgasket and 62cc EQ chambers. I cant seem to find a compressed headgasket thickness for the fel pro 5.9 gaskets. So im completely guessing at .045.

Would someone with more experience check my compression numbers?
 
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There a negitive 5cc. Don’t add the + symbol.
 
So it's a 12.1:1 static compression ratio?? That seems way too high for an iron headed street motor.
 
Compression Ratio Calculator - Wallace Racing
I got 10.74

4.03 bore
3.58 stroke
.004 piston depth
5cc (Not +5)
62 head cc
4.1 gasket bore
Still high. I tried with a .055 head gasket thickness. 10.39.
Better but pushing it. There’s way around to high a ratio, to a degree. Larger cam, more overlap, custom cam, custom head gasket. Cometic will make any thickness you want.
 
I've looked at cometic gaskets. But I've read that the head and block have to be surfaced specifically or them. Which isn't the case here. I'll make a call to comp since I have more info and see if they have anything to offer on a cam. If these KB107 pistons aren't going to work out then that's fine. They were free.
 
Search Summit racing’s web site and click away on the left hand tab with its choices. You’ll find what you need. Figure out the ratio your looking to target through the calculator and what thickness gasket will do it for you.

Fly cut the pistons?
 
I ended up buying a Hughes cam.... I went the the biggest cam that will work with the Hughes EQ heads. It's a .539/.549 lift. 218/222 duration. I've talked to a few people and looked at a few builds on the internet. Seems that a 10.7:1 can live on pump gas if the tune is right and the quench is good. I have all of the parts here in hand and the pistons were free. So I'll give it a shot and see if I can make it work. If not, I suppose I can pull the engine (again) and swap the pistons for some lower compression pieces. I was looking at the KB232 pistons and that would put my static and dynamic compression within reason.
 
1994redram said:
I ended up buying a Hughes cam.... I went the the biggest cam that will work with the Hughes EQ heads. It's a .539/.549 lift. 218/222 duration. I've talked to a few people and looked at a few builds on the internet. Seems that a 10.7:1 can live on pump gas if the tune is right and the quench is good. I have all of the parts here in hand and the pistons were free. So I'll give it a shot and see if I can make it work. If not, I suppose I can pull the engine (again) and swap the pistons for some lower compression pieces. I was looking at the KB232 pistons and that would put my static and dynamic compression within reason.
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Check for piston to valve clearance , PLEASE.... Cam is decent , might need whatever you have for pump premium , possibly some octane additive. Distributor curve. , WILL become a factor...
 
Update if anyone cares, I've got a few hundred miles or so on the engine. It's more than enough power to smoke the 245 BFG tires thought 1st and into 2nd if I let it. I had put a new street demon 625 CFM carb on it the day the stock engine blew up. I really like the carb and it runs clean, idles great, sweet throttle response, etc. But I think there might be more power with a bigger carb. I'll pick up a 675 hopefully pretty reasonable to play with, maybe a 750 if its cheap. Ended up using the stock push rods and rockers for now with the Hughes EQ iron ram heads and Hughes .539/.549 cam. The idle is addicting and I kind of wish I went for a bigger cam just for the sound.

Converted from points to electronic distributor and HEI module after a few miles. That made a pretty big difference in driveability. Points are cool and SO simple but I'm convinced they're not ideal for a performance engine. I've been slowly upping the timing and listening for detonation in different conditions. Pretty good so far, I'm up at 11° base timing and 28° or so all in. I'll wait till summer and dial it in and hopefully by then have funds for wheels and tires. Then see what she does at the track.
 
1994redram said:
Update if anyone cares, I've got a few hundred miles or so on the engine. It's more than enough power to smoke the 245 BFG tires thought 1st and into 2nd if I let it. I had put a new street demon 625 CFM carb on it the day the stock engine blew up. I really like the carb and it runs clean, idles great, sweet throttle response, etc. But I think there might be more power with a bigger carb. I'll pick up a 675 hopefully pretty reasonable to play with, maybe a 750 if its cheap. Ended up using the stock push rods and rockers for now with the Hughes EQ iron ram heads and Hughes .539/.549 cam. The idle is addicting and I kind of wish I went for a bigger cam just for the sound.

Converted from points to electronic distributor and HEI module after a few miles. That made a pretty big difference in driveability. Points are cool and SO simple but I'm convinced they're not ideal for a performance engine. I've been slowly upping the timing and listening for detonation in different conditions. Pretty good so far, I'm up at 11° base timing and 28° or so all in. I'll wait till summer and dial it in and hopefully by then have funds for wheels and tires. Then see what she does at the track.
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28° is LOW...if you had backed off compression, you could be up around 34° and make alot more power, and have better fuel economy...it kills me guys still push compression when it only adds headaches down the road.
 
Agreed and no doubt.
The timing is super low on both sides.
O need to go sky high on compression ratios in the street.
9.0-1 iron
10-1 aluminum
Cheap gas can be really n.
Add 1pt. More and it’s hi test gas.
Low return and gain.
 
Pistons were free. This is the first performance AKA non OE rebuild I've done. So it's a learning curve. I don't have any pinging problems yet. Just taking it easy. Plus, traction is horrible as-is. So more timing and power is almost pointless.
 
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