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Discussion Starter · #1 ·
Hi all - busy getting ready for the 393 build .. opinions on this cam? got the kit for 100 bucks, I think it will be a good balance between a driver and red light machine -

stock 1970 block 30 over, hyper speed pro pistons, stock truck football rods, 11:1 pro comp copy 185cc heads, 3.85 stroke eagle crank, LT headers, Rpm dual plane intake, 750 vac secondary (might try quadrajet on this one if theres space ;)

Edelbrock 7122:


Advertised Exhaust Duration300 deg
Advertised Intake Duration290 deg
Intake Duration .050 Inch Lift224 deg
Exhaust Duration at .050 inch Lift234 deg
Exhaust Valve Lift0.520 in
Intake Valve Lift0.496 in
 

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I only do hydraulic rollers these days.
They just flat out work great.
You also dont have to worry about the correct oil or additives with ZDDP.
Except for the one down side of initial cost there are only up sides then on out.
 

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Hi all - busy getting ready for the 393 build .. opinions on this cam? got the kit for 100 bucks, I think it will be a good balance between a driver and red light machine -

stock 1970 block 30 over, hyper speed pro pistons, stock truck football rods, 11:1 pro comp copy 185cc heads, 3.85 stroke eagle crank, LT headers, Rpm dual plane intake, 750 vac secondary (might try quadrajet on this one if theres space ;)

Edelbrock 7122:


Advertised Exhaust Duration300 deg
Advertised Intake Duration290 deg
Intake Duration .050 Inch Lift224 deg
Exhaust Duration at .050 inch Lift234 deg
Exhaust Valve Lift0.520 in
Intake Valve Lift0.496 in
That is alot of avertised dur for the .050 (must be hyd flat?)

My last three builds have been solid flats with the EDM lifter. Solid flats make power and have less valve spring pressures.
Before everyone piles on about oils, Call Comp, Lunati etc and ask one of the techs. I think the few flat tap failures come from too much spring. It is crazy how low a spring rate is needed to control a solid lifer.
 

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Race it, Don't rice it!
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Agreed, that cam is a long and slow. There are better ones to be had but it will still run.

FT cam, don't be scared. Use quality parts, the right springs, break in procedures, a break in oil, and the likely hood of a failure is really low.
I still prefer a roller givin the option.
 

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Discussion Starter · #6 ·
wouldnt a longer dur indicate quicker ramps? Anyway i dropped a roller in yesterday.. found a deal on edelbrock linked lifters for 300 i couldnt pass up. Got bottom end clearanced and together :) and the wife did all the basic assembly after i clearanced all the pistons and checked everything :)

616023
 

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More for Less Racer
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wouldnt a longer dur indicate quicker ramps?
Nope.
The 70° difference between advertised duration and the .050" duration is considered pretty slow ramp.
Everything Edelbrock sells(camshaft wise) is very old school and out of date.
Even their hydraulic roller stuff is not very aggressive.
A relatively quicK ramp would be 265° advertised 224° @.050"
 

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wouldnt a longer dur indicate quicker ramps? Anyway i dropped a roller in yesterday.. found a deal on edelbrock linked lifters for 300 i couldnt pass up. Got bottom end clearanced and together :) and the wife did all the basic assembly after i clearanced all the pistons and checked everything :)

View attachment 616023
You should at least use a basic dynamic comp calc before you choose a cam. Check out this one from Pat Kelly. the download link is near the bottom.


Or,, share the specs of what you are building?

bore and stroke
rod length
piston CC
head cc
compression height to deck
what is your elevation?

If you have flat top pistons and 65 cc heads you will be ~7.9 DCR. If your heads are in the 70s or a dish piston it will be a turd.
 
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