what solid cam is equivalent to a hyd 268 ?

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Isky 390144 E4 is .425 lift 260 adv 216 @.050 0n 108

I would definitely confirm those cyl pressure numbers before making a cam swap.
 
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RustyRatRod said:
In order to find a solid lifter camshaft that is "about the same" as a known hydraulic, you need to add around 10 degrees duration. In other words, a 278-280 solid will be "about the same size" as a comparable 268 hydraulic.
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Got it .
but now that 278-280 dur is getting pretty close to what I have now, right ? where would be a sweet spot for the lift then?
 
stroker402 said:
Got it .
but now that 278-280 dur is getting pretty close to what I have now, right ? where would be a sweet spot for the lift then?
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No, I am not saying that would be a good "match" for your application. Just that it is about the same as a 268 hydraulic. I think that a 278-280 solid is pretty huge for a 273. That E4 cam is supposed to be very good.
 
RustyRatRod said:
No. All the small blocks have 6.123 connecting rods.
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ok. I have another 273 engine with flat top 4 reliefs pistons and those pistons have 4 larger reliefs in them when compaired side by side . that was strange . so this engine in question has the smaller 4reliefs in them.
 
stroker402 said:
ok. I have another 273 engine with flat top 4 reliefs pistons and those pistons have 4 larger reliefs in them when compaired side by side . that was strange . so this engine in question has the smaller 4reliefs in them.
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One is probably an aftermarket version.
 
RustyRatRod said:
No, I am not saying that would be a good "match" for your application. Just that it is about the same as a 268 hydraulic. I think that a 278-280 solid is pretty huge for a 273. That E4 cam is supposed to be very good.
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ok got it .
where are you guys buying this E-4 cam ?
 
stroker402 said:
ok got it .
where are you guys buying this E-4 cam ?
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I am not sure. I think @toolmanmike can tell you. I think it;s an Erson grind. Might come straight from them. Super Shops used to be their retailer, but they have been gone for some time.
 
stroker402 said:
that is what I was thinking too. But it did bump the compression up some .
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Maybe a gnat's ***. That's splittin hairs, trust me. The one with the smaller reliefs could have that extra compression cancelled out simply with a little thicker head gasket.
 
Chry 'A' V8 E-4 Solid Seat-To-Seat 0.425 0.425 22.0 58.0 58.0 22.0 0.0 260.0 260.0 Chrysler Smallblock Street Tremendous torque & good mid-range power. 9-10.5:1 compr. , good idle stock converter. 3.23-3.70 axle ratio. Up to 625 Carb. RPM-Range (2000-5500) Valve Lift (.425 .425) Valve Lash hot (.015 .015) ADV Duration (260 250) .050 Duration (216 216) LC 108. Isky 390144 E-4 Solid
WOULD THIS BE THE CAM WE ARE REFERRING TO?
 
RustyRatRod said:
Maybe a gnat's ***. That's splittin hairs, trust me. The one with the smaller reliefs could have that extra compression cancelled out simply with a little thicker head gasket.
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You are correct . That's why I used the thinner .028 head gaskets.
 
stroker402 said:
Chry 'A' V8 E-4 Solid Seat-To-Seat 0.425 0.425 22.0 58.0 58.0 22.0 0.0 260.0 260.0 Chrysler Smallblock Street Tremendous torque & good mid-range power. 9-10.5:1 compr. , good idle stock converter. 3.23-3.70 axle ratio. Up to 625 Carb. RPM-Range (2000-5500) Valve Lift (.425 .425) Valve Lash hot (.015 .015) ADV Duration (260 250) .050 Duration (216 216) LC 108. Isky 390144 E-4 Solid
WOULD THIS BE THE CAM WE ARE REFERRING TO?
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Yes, you can buy direct from Isky also. You can also call Jim at Racer Brown he will grind you a small solid cam.
 
That's right. It's an Isky, not Erson. Sorry bout that. I had a brain fart. lol
 
AJ/FormS said:
Wow, you've got 160 cold, with that 284? That's pretty awesome. But it's also gonna be a bit of a problem to downcam.How is that 160 even possible? Did you machine the decks or the heads,or back way off on the lash?
With 8/1 Scr and an ICA of 70*, your pressure should be like 115 or less and yes, that would make a pitiful bottom end, and with 3.55s, that's a serious mismatch.
So in my head something does not compute about the 160psi number.
But if 160 is correct, then your Scr has to be up around 10.6 according to my calcs. And if that's true, then you might be in a pickle.
If the 160 is true and the 10.6 is true, then going to the .039 gasket this will drop your Scr to 10.0, and that allows down to a 62* ICA, for a pressure of 162ish.And this will up your low-rpm performance by about 54%.
>But if you lashed her loose, and that 70* ICA was more like 65,then you could get 160psi with a 10.1Scr,and it still does not compute to 8.0 Scr, so IDK...
>But if the 160 is out to lunch, and 115 is more accurate, then you have a ton of room for improvement.Too many tons.The E-4 is a 260-260-108Solid,and in at 108,might boost the pressure to 126(at zero lash) and increase your low-rpm performance 25%
> But lashed to drop 4*, the ICA would be 54*, and now the pressure would be 130@ 8/1,for a 30% Boost
So I don't know chit about 273s, so I guess this is better than a poke in the eye with a sharp stick; but I do know that 126/130psi is pretty poor.

So I guess if it was me, I'd find a second compression tester, warm it up,lash the valves, and retest the pressure at WOT, as many cycles as it takes to get two consecutive same pressure readings.
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You never get it. 273’s were never smog motors they are not 8 to 1 like late 360’s and 318’s.
 
They never came with .020 gaskets. They were replacements. I had/have too many 273’s, unmolested. Factory 273 2 barrel pistons are usually within .020 below the deck. My 64 was at .010 below deck. You never know what someone else did to an engine unless you measure everything. Been around Racing too long not to know that.
 
Every un opened 318 or 273 I have tore down had a steel head gasket, looking like .019 thick. I know plenty of people who keep and reuse them after decks have been milled.
Spray copper on it and cinch it down.
 
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66fs said:
They never came with .020 gaskets. They were replacements. I had/have too many 273’s, unmolested. Factory 273 2 barrel pistons are usually within .020 below the deck. My 64 was at .010 below deck. You never know what someone else did to an engine unless you measure everything. Been around Racing too long not to know that.
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66fs >>> didn't you own an original 65 dart charger 4 speed? it went thru meecum ? IF so, that was my car. That commando revved to the moon , 7200 rpms all day long and it really revved fast . like to know what the specs of that cam was . original owner used to race it ocassionally.
 
MOPAROFFICIAL said:
Every un opened 318 or 273 I have tore down had a steel head gasket, looking like .019 thick. I know plenty of people who keep and reuse them after decks have been killed.
Spray copper on it and cinch it down.
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My 273 had steel shims when I took it apart.
 
Here are the CAM specs : IN MY ENGINE NOW.
ERSON Part No.: E420721

Grind: HI FLOW I M

SOLID

107 Lobe Separation Angle



Overlap: 72.00



Intake Opens: 36.00 Exhaust Closes: 36.00



Intake Closes: 70.00 Exhaust Opens: 70.00



Running Clearance: 0.022 0.022 [Hot]



Valve Lift (Int / Exh): 0.510 0.510



Duration (Int / Exh): 286 286









Checking Figures @ .050" Tappet Rise



Overlap: 28.00



Intake Opens: 14.00 Exhaust Closes: 14.00



Intake Closes: 48.00 Exhaust Opens: 48.00



Duration Intake: 242.0 Duration Exhaust: 242.0



Lobe Lift Intake: 0.340 Lobe Lift Exhaust: 0.340



Intake Center Line: 107



Rocker Arm Ratio: 1.50
 
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