Cam Selection 360
- Thread starter emmett442
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Bighead440
Well-Known Member
Those who recommended the 340 cam are leaving a lot of torque out, but it would idle decent and have a broad band. From personal experience with street trucks and tow rigs, a 110*LSA would put you in the torque band quicker and with a higher peak. In my '86 D250 tow rig, I used the 272H-10 Energizer (still available in white box form from several sources, 272-216@.050"-.454" lift-110*LSA) and it was superb. Another that I have used with great results, using manifolds, is the 265DEH Comp Cams grind (in a 360, 318 use the 255DEH) which gives a good sounding idle and quick torque output with it's 110*LSA. The DEH cams are available as "Specialty Grind" shelf cams, they are just not stocking items in the catalog anymore, probably due to the "Thumpr" series they are pushing now.
Cam chosen was the Edelbrock 2177 because of it's low lift with my factory exhaust rotators, and it's in-stock availability.
With everything in great shape, this was a budget re-ring. That's why I chose not to go with new valves, springs, retainers to open up my cam choices.
This is a heavy, long bed truck, 2 barrel. It's just fine the way it is. If I wanted something fast, I'd start with a different vehicle.
With everything in great shape, this was a budget re-ring. That's why I chose not to go with new valves, springs, retainers to open up my cam choices.
This is a heavy, long bed truck, 2 barrel. It's just fine the way it is. If I wanted something fast, I'd start with a different vehicle.
Update:
I've driven this truck about 500 miles since this re-ring job. Mostly been perfect. Zero external gasket leaks, runs really good.
Peculiar observation the other day: I found oil on the intake manifold, leaking from the PCV hose at the carb connection. When I pulled the hose off, it did seem to fit tight on the carb nipple, but I trimmed a small amount off before I reconnected, just to ensure a seal.
That said, how much oil in the PCV hose is "normal"?
PCV valve is an OE type aftermarket. While running, PCV valve removed from the valve cover, no excessive blowby observed. PCV plugged back in, finger on breather hole, I do get a small vacuum on my finger. No oil being pushed out of gaskets. To me, this all points to good ring seal. Additionally, all plugs look ok. It does give one little puff of blue smoke after a LONG (5 minute) idle. This may just be slightly loose valve guides in the original heads, but I'm wondering if this could be related to the oil in th ePCV hose, a situation where oil accumulates in the hose, then gets drawn in after vacuum fluctuates in the line.
Thoughts or experiences?
I've driven this truck about 500 miles since this re-ring job. Mostly been perfect. Zero external gasket leaks, runs really good.
Peculiar observation the other day: I found oil on the intake manifold, leaking from the PCV hose at the carb connection. When I pulled the hose off, it did seem to fit tight on the carb nipple, but I trimmed a small amount off before I reconnected, just to ensure a seal.
That said, how much oil in the PCV hose is "normal"?
PCV valve is an OE type aftermarket. While running, PCV valve removed from the valve cover, no excessive blowby observed. PCV plugged back in, finger on breather hole, I do get a small vacuum on my finger. No oil being pushed out of gaskets. To me, this all points to good ring seal. Additionally, all plugs look ok. It does give one little puff of blue smoke after a LONG (5 minute) idle. This may just be slightly loose valve guides in the original heads, but I'm wondering if this could be related to the oil in th ePCV hose, a situation where oil accumulates in the hose, then gets drawn in after vacuum fluctuates in the line.
Thoughts or experiences?
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QUINN FORBES
Greendemon
I like what you have to work with, all makes sense to me.
I was wondering about the rotators myself and what the average max lift we can use with those spinnie things.
I know they were not intended to be used in performance engines but HP TV
built a budget 360 with rotators with ok results.
They used summit 276/288 .441/.441 cam up to 3800 rpm and resulted in 307 hp /381ftp of torque on the dyno…with retainers!
They used cast dished pistons, no mention of compression.
I was wondering about the rotators myself and what the average max lift we can use with those spinnie things.
I know they were not intended to be used in performance engines but HP TV
built a budget 360 with rotators with ok results.They used summit 276/288 .441/.441 cam up to 3800 rpm and resulted in 307 hp /381ftp of torque on the dyno…with retainers!
They used cast dished pistons, no mention of compression.
I see you’re running factory valve covers so I assume they have baffles in them. I’m running aftermarket Moroso covers and had to fabricate baffles as best I could but a little too much oil was being sucked up so I installed a Moroso oil separator which did the trick for my setup. Some type of inconspicuous separator installed in the pcv line would be my advice.
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Factory covers with baffles, yes.
One little tidbit I left out is that I also get a ton of whistling from the PCV, even after changing it.
Curious: The PCV is pulling a lot of oil and it's noisy. So, I put a vacuum gauge on it. The engine's almost pulling a whopping 23 inches at idle!
Now, when I set the timing, I put as much into it as it would take. I landed on 18-19 base, 37 all in. Balancer accuracy verified during the build.
That seems like a lot of initial to me, even for a stock lo-po engine, and that also seems like a lot of vacuum to me. So, I backed the base timing down to a reasonable 11 or so. Whistling PCV has stopped. Vacuum down to a healthy 19 inches. Puffs of smoke after idle disappeared so far.
I'm curious if it's possible that too much vacuum can pull too much oil thru the PCV and passed the valve stem seals? Someone check my sanity with that assumption!
If so, I suppose if I want to get back to my original timing setting, I'll need a different carb than the original that will better fit the whole system. After all, the original carb was sized by Chrysler with the original cam, original timing settings (TDC base), right?
One little tidbit I left out is that I also get a ton of whistling from the PCV, even after changing it.
Curious: The PCV is pulling a lot of oil and it's noisy. So, I put a vacuum gauge on it. The engine's almost pulling a whopping 23 inches at idle!
Now, when I set the timing, I put as much into it as it would take. I landed on 18-19 base, 37 all in. Balancer accuracy verified during the build.
That seems like a lot of initial to me, even for a stock lo-po engine, and that also seems like a lot of vacuum to me. So, I backed the base timing down to a reasonable 11 or so. Whistling PCV has stopped. Vacuum down to a healthy 19 inches. Puffs of smoke after idle disappeared so far.
I'm curious if it's possible that too much vacuum can pull too much oil thru the PCV and passed the valve stem seals? Someone check my sanity with that assumption!
If so, I suppose if I want to get back to my original timing setting, I'll need a different carb than the original that will better fit the whole system. After all, the original carb was sized by Chrysler with the original cam, original timing settings (TDC base), right?
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Bryan Lohmiller
Well-Known Member
Do you have a baffle inside the valve cover to keep the PCV from sucking up the oil it sounds like you don't
Post #57.
No, not a lot of initial timing. Probably the most misunderstood subject on this & other forums. The factory HAS to be conservative with timing because it does not know the end use of the vehicle. I think you are getting excessive blow by [ puff of smoke ] & this pressure is foprcing oil into the PCV.
No, not a lot of initial timing. Probably the most misunderstood subject on this & other forums. The factory HAS to be conservative with timing because it does not know the end use of the vehicle. I think you are getting excessive blow by [ puff of smoke ] & this pressure is foprcing oil into the PCV.
With so little mileage on it, the oil in the PCV system would be last on my list of worries. Do keep a check on it, but I bet it stops once the rings are seated good.
From what I can tell, no significant blowby.
PCV removed, there is just a light steady whisp of vapor from the breather. No chooching, no real pressure.
I hope so.
FWIW, dialing the base timing back and bringing the vacuum to a reasonable level did stop the excess oil in the PCV for now.
I did recurve the distributor and adjust the slots (already had an fbo plate) to get the power back. Total is the same, springs are lighter to have it come in quicker. So, it doesn't even feel different than it was at 19 degrees.
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Good job. Well done. Kim
Drove it for a couple of hundred miles since last post
Not sure if too much vacuum is a typical concern or not, but my issue seems to have resolved after bringing into a normal range. No more excessive oil in PCV line.
I've ended up at 10 degrees initial, 37 total. 20" vacuum. Switched one spring to a ultra light variant to regain low rpm timing advance.
Not sure if too much vacuum is a typical concern or not, but my issue seems to have resolved after bringing into a normal range. No more excessive oil in PCV line.
I've ended up at 10 degrees initial, 37 total. 20" vacuum. Switched one spring to a ultra light variant to regain low rpm timing advance.
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