Help picking a cam

Let's say for example I picked the crane 114142. How much will those 1.6 rockers help? Those also add a good bit of cost in and of themselves. I already have a good set of stamped steel 1.5 rockers that have very little run time on them. I know that roller rockers are superior on every way but my budget is limited and that's another 300 bucks.
 
you could do what maybe 80% of us are forced to do, because of similar budget limitations, you install the cam with the current rockers and up=grade the rockers to the higher ratio roller rockers when the check book balance allows at a later date, that way youll see the improvement both the cam, and later the rockers made
 
it might , or might not,be required, but you won,t know for sure,
without checking clearances ,and you can,t do that until you get the roller rockers.
(the clearances vary between brands)
and yes its very common for the same push-rods to work, but its not granteed






 
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Run 1.6 rockers and 1.5 on the exhaust. Your valve lifts will come out to .484/.480 and
all the valve spring heights can be set the same.
You can buy split sets of rockers - (8) 1.5 & (8) 1.6. I know Jegs has them.
 
Grumpy said:
it might , or might not,be required, but you won,t know for sure,
without checking clearances ,and you can,t do that until you get the roller rockers.
(the clearances vary between brands)
and yes its very common for the same push-rods to work, but its not granteed
Click to expand...

There also differences between brands in where the pushrod cups in the lifters are located.
That will also affect your final pushrod length. So will how much your heads have been machined,
if the block has been decked, and your head gasket thickness. Pushrods are the final item you measure for.
 
Speaking of head gaskets do you guys recommend something like the felpro 1094 gasket to bump my compression up a hair? Isn't there a cam with more lift that has the same duration so 1.5 rockers would be all I need? I see cams withlike 489 lift with intake Duration around 219 but exhaust at 227 is that too big for 9.2 to 1 cr. It's only 3° more then that crane is that a big difference?
 
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You will want to get the quench to .040".
That is the clearance between the flat top of the piston at TDC and head surface.
Again, you will have to measure.
 
so what do you guys think about a cam with only 3 degrees more duration on the intake and 2 degrees less on the exhaust but has 468/489 lift?
 
Let's go back and look at the roller cam Howards recommended, for example.
That number cl110245 comes in 3 versions: -14, -12 and -10. http://howardscams.com/search.html#!sq=cl110245
All have the same lift and duration.
Look at the descriptions and let's see what a 2 degree change makes.
The -14 says mild idle.
The -12 says fair idle (but I think it should say GOOD idle)
Because another 2 degree change (-10) says fair idle.
You see, it's not that simple. 2 degrees can make a BIG difference.

If you are talking about 219 degrees at .050", probably too big for what you originally asked for.
Camshaft selection is an area where bigger does not always mean better.

4doorscooter said:
Isn't there a cam with more lift that has the same duration so 1.5 rockers would be all I need? I see cams with like 489 lift with intake Duration around 219 but exhaust at 227 is that too big for 9.2 to 1 cr.
Click to expand...

There might be, but with 9.2 compression, your bottom might get a little soggy.
Do you have actual flow numbers for those Vortec heads?
They might be all done at .450" lift, so opening the valve to .525" does not gain anything.
Grumpy will tell you that it's all about the entire combination. All the parts need to work together, like a symphony.
One part alone will not give you huge gains.
Now we have to bring DCR (Dynamic Compression Ratio) into this mix.
Simply put, no compression starts to build UNTIL BOTH VALVES ARE CLOSED.
And that is where that 2 degree change can make a big difference.
 
messing with cam quest has been giving me recommendations int the low 220 duration's any thought on why? are they just trying to sell bigger cams because peopel are so concerned with idle sound?
ya i have flow numbers for vortec heads here you go.

Lift (in.) Intake (CFM) Exhaust (CFM)
0.100 70 49
0.200 139 105
0.300 190 137
0.400 227 151
0.500 239 160
0.600 229 162
 
4doorscooter said:
messing with cam quest has been giving me recommendations int the low 220 duration's any thought on why? are they just trying to sell bigger cams because peopel are so concerned with idle sound?
Click to expand...

Either that, or you are not being honest about what you are putting into the program.
Select the next step DOWN under usage.
 
I just re-read your first post.

4doorscooter said:
The engine is a 355 9.25 to1 compression and will hopefully have vortec heads if they check out at the machine shop. Exhaust is headers connected to an x pipe and dual MagnaFlow mufflers. The transmission is a tko 600 with . 64od and the rear end is an 8.5inch 10 bolt with an Eaton posi and 3.42 ratio and 26" tall tires.
Click to expand...

You have overdrive and 3.42 rear gears. You will need to maintain enough low end torque so that the car is
not lugging or bucking when in OD and low rpm. Yeah I know the top end is fun, but if you are stumbling off the line
and can't get moving that well, then how much fun is that? You don't want to be blown away by Toyotas do you?
 
4doorscooter said:
ya i have flow numbers for vortec heads here you go.

Lift (in.) Intake (CFM) Exhaust (CFM)
0.100 70 49
0.200 139 105
0.300 190 137
0.400 227 151
0.500 239 160
0.600 229 162
Click to expand...

Good. So these heads are about done at .500 lift.
Are you going to do any port matching or bowl work to improve them, or just bolt them on?
You don't have to. They will work fine as is for your application.
 
Im not really that concerned with allot of top end power and I think that I will eventually upgrade to 3.73 gears since i have the over drive. I am not experienced with doing any type of head port work but i will go through them and clean up any casting imperfections ext. I am afraid i would do more harm then good attempting a port job without hands on guidance.
 
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okay i figured the dynamic compression calculator out so it looks like with the crane cam you both recommend i get a reading of 7.42, the 264 mega gives me 7.84 and the lunati gives me 7.69 what does this tell you guys? Just guessing but my thought is the 264 mega is closer to ideal due to the 108 lsa vs the 112 of the others.
 
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Less than 8:1 DCR is sluggish response and/or leaving performance and economy on the floor.
8-8.5:1 is the sweet spot.
Above 8.5 DCR requires race gas to prevent detonation.
 
so either im not using the calculator right or even these mild cams are to big!? the strange thing about the calculator is it wants advertised duration and not duration at .50 isn't that strange and inaccurate?
 
using a different program my new numbers for the crane are 8.6 for the crane 8.49 for the lunati 60102 and 8.42 with a lunati that is one size bigger and i cant find the intake closing point for the 264 mega which is what this calculator wants. So it seems like the lunati 60102 is basically right in the sweet spot of what i want right? The link below is the cam card for the lunati 60102. I've been reading allot of good things about this line of cams they were designed by the guy who designed Ultra Dyne cams which were top notch at one time and he went to lunati and designed these voodoo line cams. His name on forums is UDharold i believe. Let me know what you guys think.

http://www.lunatipower.com/CamSpecCard.aspx?partNumber=60102
 
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