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Discussion Starter · #1 ·
Hi everyone, I just have a quick question(s) about a certain camshaft I would like to put in my motor for a daily driver 1980 c10 long bed truck.

The motor is a crate gen1 350 sbc with an edelbrock 1406 600cfm carb and stock th350 transmission.

I'm planning on installing an Elgin E1785PM camshaft (some say it is a copy of a 274h06 cam)

My following questions are:

Will it fit any gen1 sbc?
How would this cam affect the vacuum compared to the stock one (i have hydroboost brake assist)
Do i need to change anything in the carburetor?
What about the transmission? (torque converter, vacuum modulator, etc.)
Do you set the timing just like you would with any other stock small block?


Thanks for reading!
 

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What are the specs for this cam, so we don't have to waste time trying to hunt them up??

What head castings are on the engine, and what compression ratio does it have??
 

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A builder cannot simply reach out into thin air and choose a camshaft for a motor. It is not a stand-alone part. It relies on other parts and other characteristics of parts and the builder must coordinate with these parts and characteristics in order to return the results that he/she is looking to achieve.

If you want real, intelligent answers to your questions, do some snooping around your motor and find out, for instance, what the static compression ratio is. That's one of the first things you need to know before choosing a cam. Once you know what the SCR is and you have used a vacuum gauge hooked to the manifold and you know what the vacuum is at idle and what the idle speed is at that point, get on the phone and talk with the Elgin tech guys. They will be much better equipped to answer your questions than any of us on this forum. All of us are flyin' as blind as you are.

.
 

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Hi everyone, I just have a quick question(s) about a certain camshaft I would like to put in my motor for a daily driver 1980 c10 long bed truck.

The motor is a crate gen1 350 sbc with an edelbrock 1406 600cfm carb and stock th350 transmission.

I'm planning on installing an Elgin E1785PM camshaft (some say it is a copy of a 274h06 cam)

My following questions are:

Will it fit any gen1 sbc?
How would this cam affect the vacuum compared to the stock one (i have hydroboost brake assist)
Do i need to change anything in the carburetor?
What about the transmission? (torque converter, vacuum modulator, etc.)
Do you set the timing just like you would with any other stock small block?


Thanks for reading!
Lots of rumble not a lot of power. It's an old fashion design with a lot of ramp nearly 60 degrees worth of them. Problem with 60 degrees of ramp between zero lift and .050 inch lift is it greatly delays the point where the cylinder starts making compression pressure while on the suction side the ramp offers little to flow being pushed by atmospheric pressure. This cam makes the engine sound like it's packing and has all the negatives of needing a higher stall converter and higher compression but noise and stagger aside it doesn't deliver the goods compared to modern designs.

On the positive side with the gentle lobes it doesn't need nasty spring pressure and it doesn't tear up lobes and lifters.

Part of the problem with this cam is that it needs a lot of compression to compensate for its long ramp times. I'm guessing your crate 350 is not a high compression version so you need to start thinking of better heads and pistons.

If that is true (low compression crate that is) then you need to shop for something like a Comp XE or Lunati Voodoo. These have half the lobe ramp degrees so they get with the program much sooner, the down sides are they make more go than noise so people arent' all that impressed with your engine till you turn it loose on them; and these cams especially getting into the 268 degree range and up do have a habit of chewing up lobes and lifters if not broken in right. The milder versions around 252 to 258 degrees are not so much a problem in this regard as they don't need super springs to keep the valve train tracking the lobe.

When it comes to valve springs use beehives or conicals, you get the performance of much stiffer springs without the lobe/lifter eating pressures. GM's stockers work very well with street performane cams.

And yes that cam fits Gen I blocks. If you put on better heads like L31 Vortecs of equivalent aftermarket part that boosts the compression and chamber efficiency with a thin gasket or some milling these heads will push the compression up to the 9 point somethings where these type cams start to work pretty well. Aluminum heads, even inexpensive ProComps, let the compression be pushed in the 10 to 10.5 range than these cam reall cook finally makeing power to go with the swagger. You have to be aware that any of these long ramp cams are left over designs from the leaded gas muscle car era when 10 to 1 was pretty common and 11 or 11.5 was seen on many models. Today's unleaded high 80 to low 90 octane require a different approach if not different materials such as the aluminum head to get the power up with these type cams.

For your personal cam comparison work the ramp is the difference between zero lift and .050 inch. Be careful of DCR calculators that only use 15 degrees in the ramp, this is for modern cams. The one you're looking at has nearly 60 that is split between the leading and trailing edges of the lobe so you can assume that's 30 degrees on the side. These long ramps don't offer much on the intake side if only atmospheric pressure is pushing, but they are havoc on the closing side where while the valve may not be open much the rising piston is generating a lot higher pressure than atmospheric so that pumps a lot of inducted mixture back into the intake system. This is the essence of the DCR calculation to find enough compression to cover the density loss in the cylinder i.e. make what's there work harder.

Bogie
 

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E1065 or E1029 would be better choices with the stock torque converter.

The E1785 needs 2400 stall converter to work well, and a little more compression than your crate motor likely has. Likes to have 3.31 or deeper gears also, figuring 28" diameter tires. Will need to have more initial timing, so you will have to recurve the distributor
 

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Discussion Starter · #6 ·
Thank you so much for your input guys!

I will just keep the money i'm supposed to spend on this in my little piggy bank and save up for better stuff. In the mean time, i'm going to find some extra work to do to get me enough cash for a nice pair of vortec heads.

I guess you DO need to have that power to go with the swagger :cool:

I'll be back once I get those, and i'll make sure I write the numbers down next time.

Thanks again!

:welcome:
 
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