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Discussion Starter · #1 · (Edited)
Hi all

I just Wanted verification please that i am Correct in Choosing The Voodoo 268 cam for my application? Street use Primarily With Two visits to track each year Only!

I would appreciate your thoughts as others are Suggesting larger which I am hesitant of as i do Not want to error and end up with a poor streetability! I do Want as much as one can get OF COURSE!

Thank you in advance!

Chris.

355 ci
Afr 195 ported polished
10.1 Forged pistons
1.5 roller rockers
Tko 600 5 speed .84
Dual friction clutch (centerforce)
SFI steel flywheel (Centerforce)
3:73 rear gears (12 bolt, posi)
Msd 8394 ignition/with 6AL box
Performer rpm manifold
Avenger 670 carb
2 1/4 Exhaust with flowmasters
Power steering/ brakes
15 in Rear wheels
Car weight 3650 lbs
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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some might say to go to the 276 with your combination buy I'd keep in mind that your cruise RPM in OD will be pretty low at normal highway speeds. too much and you won't be able to cruise in OD without keeping it up to 90MPH. IOW, do the 268.

BTW, the rest of your stuff looks to be really well thought out for a street performance car with a small block.
 

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I agree with Tom. I think the 268 is the best all around choice for your combo.
 

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Discussion Starter · #5 ·
Thank you for your votes of confidence on this.

I also read in posts that someone recommended having this cam ground on 108 Lca instead of 110? Would there be any real benefit to having it ground on a 108? This is the only other question i have in this regard.

A great deal of reading in the forums and alot to digest but i thank you for having a great group of people on these forums to put things in the proper perspective.

Thank you again.

chris
 

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no, I wouldn't do that. It would make the idle a lot rougher. Again, think about what your RPM will be while cruising at your normal cruising speed. Your cam needs to be at least at the bottom of it's intended RPM range at that RPM. Your OD times 3.55 puts you with a final drive ratio of 2.93.

Use one of the many online speed calculators to figure your cruise RPM at your normal cruise speed with whatever size tires you have. Compare that number with the bottom of the cams' intended range.
 

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my experience with lower lca's is they pull harder and sound great at idle, along with loads of torque. Downside is you get less vaccuum and if not matched up properly with the rest of the cam specs the cam will fall off at the higher revs. Might want to call lazer cams up and ask what he suggests as he uses 108 LCA on most of his cams. Great guy to talk to also and makes a killer cams. What's wrong with your current combo? As somebody mentioned a vehicle always runs way better being under cammed than over.

here's a little read for you. Maybe harold will chime in why he went with a 110 lsa on the cam you have as I'm sure he has his reasons.

http://http://www.popularhotrodding.com/tech/0607phr_camshaft_basics/lca_selection.html
 

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idle is too rough for mass market sales with a 108. this counts when you are selling and advertising nationwide.
 

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idle is too rough for mass market sales with a 108. this counts when you are selling and advertising nationwide.
a lot of people like this rough idle and ask for it. The thumper cams from comp comes to mind. But you're correct, look at how wide some of the stocker cams are.
 

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tfrom the most excellent Bowling and Grippo site:

Input Parameters Are the Following:

* Differential Gear = 3.55 to 1
* Transmission Gear = 0.84 to 1
* Tire Diameter (Inches) = 26.00
* Vechicle MPH = 70

Computation Results:
# Computed Engine RPM is 2699 at 70MPH. Not all that low.

http://www.bgsoflex.com/auto.html

these guys stuff is dead nuts accurate.

Lunati has this on the 268:
60103 60103LK 268/276 227/233 .489"/.504" 110/106 Hyd/Hyd 1800-6200

you'd be a few hundred RPM into the sweet spot at 70 MPH cruise
 

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Discussion Starter · #11 · (Edited)
I have a lunati grind in it presently but am not sure of specs other than it having a 106 LCA and somewhere in the .470 lift and .480 and it just rolls over on itself after 5400 rpm .

This on the advise of parts guy who was into roundy round and i believe meant well! I had the performer rpm Cam prior and it Was superior to this stick. I could shift at 6000-6500 no problem with the rpm cam. That was before I even added the AFR 195 heads? So I think i let myself get talked into going too Small if thats possible? It certainly has a lumpy idle.

Presently Crusing At 60mph Im at 1900 rpm ! Prior to this with the muncie and 3:31 rear gears i was 2800rpm and 60mph. yes with 26 inch tire.

Thank you.

chris
 

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In your situation with the lunati not working like the eddy cam, it really comes down to the fact that there are different cams for different situations. For example....I beleive that RPM cam has a big wide 114LSA. If its not 114, than its 112 but no tighter. But Im pretty sure its 114. Either way, the wide LSA spreads out the power curve. They arent as potent as tighter LSA cams can be....but they typically spread over a longer power curve and hold on to a higher RPM.

Now you got that mildish lift/duration, older lunati grind to compare it to with a much tighter LSA. When speaking of two comparable cams...the one with the tighter LSA typically builds better peak numbers, builds more suddenly, and also drops off faster(shorter power curve but with bigger power). A mildish cam cut on a 106LSA would be expected to fall off fairly soon and somewhat suddden, especially in comparison to the wide center of the old eddy cam. Youd typically need bigger lobes to get the tight LSA cam to carry as high as the milder, but wide LSA edelbrock cam. The application will help dictate the LSA among all the other cam specs.

So in your situation with the mildish drivetrain and mostly street time, tighter would not be better. Having that cam cut on a 108 could definitely be more potent and do more work if everything else was up for it. But with all the stats on everything else, keep it at a 110. It will perform better that way in your overall drivetrain combo. So per your example, its real tough to compare the eddy to the lunati mentioned and expect them to act similar, cause they are ground for a bit of a different purpose. That situation isnt a case of a bad cam VS a good cam.....just the wrong cam VS a more suitable cam. By the way, I also vote voodoo 268 cut on the 110 as is.
 

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Discussion Starter · #13 ·
Thank you Tom , Greg , Furball, Fabio and RB69ss for your input into this , it is greatly appreciated. This I believe was the last piece of the puzzle that needed attention to my particular combo and you have confirmed my suspicions and kept me on the correct path!

Thank You.
 
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