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Chasing dreams with a ball bat
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Discussion Starter · #1 ·
So here's the question:

I have a 1948 Ford pickup that is a street rod / hotrod, with a 10.5 SBC, Dart Iron Eagle 200cc heads, dual plane intake, 700R4 tranny, 3.73 gears, and a whopper of a Magnum cam. It's the 292H, with 244/244 @ .050 timing 110 LSA on a 106 ICL. It was a "crate" motor that I actually bought online for a pretty good deal, and that's the cam they put in it.

This truck has A/C on it for summer cruising and with 94 degrees of valve overlap, it just isn't real happy idling around town with the A/C on, stereo on etc. It's just too much cam I think. Add to that I don't have the converter that I need either, although smoking the hides is not an issue at all.

I still want a little hotrod sound left, but I gotta cam this thing down a little. I think I may be able to get a little better mileage so I can drive it more too.

So the question is: what cam shoudl I step down to? I can't decide if I should go into the 270's or 280's.

I'm thinking the ISKY MEGA 280 230/230 @ .050, 108 LSA, would work well. Has 74 degrees overlap, which would be much more manageable, but still have some lope, right? :mwink:

DCR would be good, in the 8.0 range, so that should work I think.

Any thoughts??
 

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A comp magnum 268 will give it a lopey idle, and it only has 218 duration. The isky cam should work nicely. if it were me I would use a 224 duration cam, it would still have plenty of lope and good street manners with mileage, But I`ve always been conservative on my cam picks since I like low end torque. Have you looked at the comp Extreme or the Lunati Voodoo line? I hear they both have been getting some real good reviews.
 

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You might consider a Comp Cam XE274, 230/236. I have a T-Bucket rod with 355 SBC, Ebelbrock dual plane intake, flat tops and HEI, putting in this 274 and adding Edelbrock Alum 70/170 heads. This is after a ton of research and questions on this forum and others. Sounds like with your set-up, this 274 would help calm the mill down to usable. Just my opinion :thumbup:
 

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You got a leaky spark tube...
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I had a Comp Cams 280H in a 350 for a while and I really liked it. It sounded good yet I was able to drive it around town. It's similar to that Isky cam you mentioned with 230 deg @.050 and .480 lift intake and exhaust.
 

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Chasing dreams with a ball bat
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Discussion Starter · #6 ·
rac43 said:
You might consider a Comp Cam XE274, 230/236. I have a T-Bucket rod with 355 SBC, Ebelbrock dual plane intake, flat tops and HEI, putting in this 274 and adding Edelbrock Alum 70/170 heads. This is after a ton of research and questions on this forum and others. Sounds like with your set-up, this 274 would help calm the mill down to usable. Just my opinion :thumbup:
I have considered both the XE274 and the XE268 - probably the 274 would be better for use with pump gas.

ISKY claims that a straight pattern cam (when combined with good heads, headers, and a free flowing exhaust) will "always make more torque."

Are the extreme energy from Comp more aggresive lobes than their Magnum line I wonder? The magnum cams are the straight pattern. Don't know how much differance it would really make anyway.


Was just reading about the Z cams - it's nice that I was able to find data on the @.200" lift duration figures so that I can compare to the ISKY MEGA line. Haven't found where Comp or Lunati will tell that figure. If you know the @.050 duration is the same, and one is longer duration @.200, then you know which is "more aggressive" it woudl seem.

Not that the MOST aggressive is necessarily the best. ISKY talked about that, too. The ISKY website is pretty good. Crane's is looking good, too. Holley's website is and probably always will be - weak. Just can't find the info I need. :spank:

I'm going to do some more comparing and see how the Z cams rate compared to the ISKY MEGA. I'll report back. :D
 

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Chasing dreams with a ball bat
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Discussion Starter · #7 ·
So on the comparison between the Crane Z cams and the ISKY MEGA, it turns out that the Crane does, in fact, have a more aggresive lobe profile. I compared lobes of similiar duration @.050" and then checked the duration at .200" lift as well.

Here's one example:
Crane Z cams 224' @.050, 137' @ .200", lift with 1.5 = .473"
ISKY Mega 224' @ .050, 134' @ .200" lift with 1.5 = .480"

So that means the Crane is a little more aggresive. Is that a good thing in the long run??? Or would I be better off to stick with the ISKY?

ANother thing - the Z cams are fairly limited as far as what they make. All are 110 LSA, the ISKY is 108. The Z cams are dual pattern, the ISKY is single. I plugged the numbers into Engine Analyzer Pro, and my motor will like the ISKY better, although it's hard to take into account the fact that the Crane is a little more aggresive, so in the end it might be a wash.

COnsidering the Z cam will be harder on lifters and such, I think the ISKY may be the better choice.

Thoughts?
 

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Another consideration will be the weight of your truck (much more than most cars and hot rods) and whether you plan to use it as a truck.

I have a 222/222 at .050 GM cam in my GMPP SBC 350, and its borderline for most uses of my K25 3/4 ton 4x4. The engine really comes into power it at about 3500 rpm (70 mph), so I have good cruising and passing power, but the cam does not help low end torque and pulling power. I'm also using a stock TH350 and torque converter, so I don't get the benefits I might have from a higher stall converter.

I think a cam in the range of 220-225 at .050 will give you a moderate lope and good sound, but bring back your vacuum and idle speed.

Bruce
 

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Chasing dreams with a ball bat
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Discussion Starter · #10 ·
75gmck25 said:
Another consideration will be the weight of your truck (much more than most cars and hot rods) and whether you plan to use it as a truck.

Bruce
THis is hotrod only. NO hauling. The bed is entirely custom made, flames cut into the wood and stuff. Tailgate, bed sides etc. all handmade

It only weighs about 3400 lbs, so it isn't heavy like a "real" truck would be. Remember, this truck cam stock with 110 HP flathead and a non synchro 4 speed tranny.

I'm thinking ISKY!! Probably do the MEGA 280, which will help keep the DCR down to a manageble level - the 274 was pushing it. My local guy said the 274 would be more expensive since it's a not so often run cam I guess.


Thanks again everyone for the replies! I do appreciate it! :thumbup:
 

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Chasing dreams with a ball bat
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Discussion Starter · #12 ·
I did a test of the MEGA 280 versus the Magnum 280H, and Engine Analyzer said that the 108 LSA of the MEGA would make more torque and a bit more peak HP as well on this motor.

Course, would that happen in the real world? I dunno. Probably comes down to the level of tune on the motor at that point. :mwink:
 

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Chasing dreams with a ball bat
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Discussion Starter · #13 ·
Update for anyone that was following:

I did put a new cam in this weekend. Local speed shop had a Crane Energizer cam , 228/228 @ .050, 112 LSA, on a 107ICL. I really wanted a LSA of 110 or 108, but I thought I would give this a shot. The idle is nice and mellow, still a little lopey when in gear, and is much more manageable on the street. And the A/C compressor doesn't even phase it :D That sure will be nice next summer. :thumbup:

This little truck is really fun to drive now. Less cold natured as well, which is nice when you drive it to work once in a while. Gotta watch the wheelspin though!

Again, thanks to all for your suggestions and help!!
 
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