Richard Daugird

My car is a fully optioned '74 coupe, A/C, P/S, P/B, etc. so I figure it weighs 3500 or so. I have a four speed and 3.55 rear gears, and will be using header side exhaust. .030 over 350 with flat tops. My heads have had screw in studs and guide plates installed, and I will cut the spring pockets and valve guide bosses, as well as some mild porting/blending. Holley 680 Street Avenger carb, and an Edelbrock RPM Airgap intake.

I'm thinking low end torque is what I need for stop light to stop light fun, high RPM power probably won't do me much good. Might go to the strip a few times for fun. Won't see a lot of freeway time, ten mile runs to Galveston on nice days would be fairly common.

I love the sound of a lumpy cam, and they do turn heads on cruise night, but I want the car to perform as well. Don't care about gas mileage. I ran the numbers in the Comp Cams Cam Quest software, and it recommended an Extreme Energy 4X4 cam. I called Summit and their tech agreed. This is the cam:
https://www.summitracing.com/parts/cca-k12-243-3

Any thoughts or opinions before I pull the trigger?

cv67

was not thrilled with that line at all. Suppose in theory it oughta work it just didnt imo
Ask the designer of that line what his opinion of them today is. Im not slamming them they make plenty of good products

An Isky mega 270 cam would be awesome in that combo 224//270/470/108lsa would pull hard up to about 5500ish
Their 280 could probably use a teeny bit more gear have a feeling would still pull well. 232/280/485 lift 108 lsa.
They have a 264 thats decent but with a stick think you may want more once its in.
(Id use the 270 base on your needs)

Either one would run pretty hard midrange "hit" is nice and strong.

Theres other brands that are good also just a personal fav.

Just my .02 had every single XE FT and one XFI HR go flat fast maybe others have had better luck.

You may already know this but dont go after porting a Vortec the way most would on an old Gen 1 head youll lose more times than not.
Focus on getting the exh #s up for that cam it will haul butt for what it is.

Richard Daugird

Thanks, I'll look at those cams as well. I did a little research on porting the Vortecs, I will do it right. Don't need much from what I've learned.

Scottd

Are you committed to keeping the vortecs? You cant run much lift with them and the machine work will set you back a few bucks, you will need an entire cam set to include springs as well....OR.....

Just buy a set of Edelbrock aftermarket heads. They will cost about 300 bucks more than the vortec conversion, but its so much less hassle and will produce better numbers. Dont get me wrong, vortecs are great heads, (I did the conversion myself) but after I got done with machine work, springs, cam selection and such, I would have been better off with a set of edelbrocks.

Richard Daugird

I'm committed. They are rebuilt, new valves. Got a new Vortec intake as well, useless on other heads. I can cut the heads at home with $150 worth of tools(I may be even able to borrow them, waiting to hear back from another forum member), and sell the tools after and get a few bucks back.

68post

http://www.competitionproducts.com/E...mshaft-C_krJPY

This may work well for you, and I agree on the 270 MegaCam also. In your application I'd consider a Comp Magnum 270 over a Comp XE grind.

If you're doing some exh porting on the vortecs a single pattern cam would give you what you're seeking.

dochorsepower

I'll throw in my two cents worth, and that's what it is worth. The vortec chamber will probably give you the low end responsiveness you are looking for and a cam with a 108 LSA will probably give you some lumpiness although that may hurt the low speed characteristics a little.

Richard Daugird

With this cam, I could use the stock Vortec springs, right? All I would need to add would be lifters, that would save me several hundred dollars. What lifters are recommended for that cam?

68post

It's just a hyd lifter cam - so good hyd lifters. You can buy it as a kit from Northern Auto Parts too. But use the recommended springs or at least compare them to others you may consider using.

Smart shopping is your best friend.

cv67

Those stock lift rule cams can be fun on the cheap
Sound rumpity real strong torque but dont kill the valvetrain
Know even though lift isnt high may want a different spring rate so dont just leave stock old springs in it as said. Set em up right so they dont float will run So much better. Didnt know Elgin still sold those
old school type deal but bet ir runs good.

jim-81

I have the summit Vortec's and Comp XE268 cam: https://www.summitracing.com/parts/c...make/chevrolet

It's a nice combo. Although I wiped a couple lobes on my first install, this time I think I got it right. So far so good using all Comp oils.

Idle is nice and choppy, but good vacuum. I don't have anything to compare it to but this cam runs great, good low end up to where I don't push it past 5000.
Jim

gg521

Instead of calling Summit, why don't you call the cam manufacturers directly. There are a few good ones. All you are going to get here is opinions not facts.

Richard Daugird

That is part of the plan. I just wanted a few opinions first.

lionelhutz

The Crane Z-268-2 and Lunati 10120702 have worked good for me. The Crane is similar to the Comp 268. I would think about the Lunati 10120703 cam for your application. If not it, then the Lunati 10120702.

63mako

Comp cams 12-319-4 268AH-8 268/276 222/226 .464/.464 108 LSA

Comp Cams 12-321-4 270AH-8 270/280 224/230 .470/.460 108 LSA

Scottd

Well, you're stuck now, ya dum bastag.

I looked into cutting my own spring pockets with an aftermarket tool, but I was afraid I wasnt going to be able to make a perfect perpendicular cut and opted to outsource mine. The machine shop didnt charge me a whole lot more than what the tool and time would have cost me. You are going the exact same route I took. Id suggest that you call Summit and speak with one of their techs. When I called, they put together a package with a cam, lifters, pushrods and springs that worked really well with my Vortecs. The 'vortec' upgrade is a lot of fun, but its pretty labor intensive when it comes to choosing a cam. Keep us posted!

PS- Listen to 63 Mako- that dude has forgotten more about cams than Ill ever know. He helped me cam my 468.

Richard Daugird

I have a milling machine.

KeithDyer

We have found a couple of Elgin hydraulic camshafts that work well.

SBC is E920P 230@.050 .480 lift 109 LC

BBC is E929P 230@.050 .544 lift 109 LC

They have a head turning lope but are extremely driveable.

Folks tell me that their motors run cooler also, not understand but they do.

The car in my avitar has one in it and his 55 BBC runs one also.

High quality and inexpensive (find a decal you like and slap it on the fender . . . )

63mako

Lift on vortecs limited to .470 or thereabouts unless you modify them, go with different springs and -.050 retainers or go with longer valves. Check retainer to guide/seal clearance.

cv67

P.A.W. used to sell that under their name used one in a 327 yrs ago ran good.