MWieczorek

Hello gang,

I'm looking at some possible upgrades to my 'vette. Today, it's a 1972 with the base base 350 and a 4 speed. Rear end ratio is 3.55:1 (at least I'm pretty sure it is). (EDIT: its also got long tube headers of some type and a decent 2.5" exhaust.) It's a fun car, but defenitely lacking in the acceleration department. So, Id id some surfing on Summit's website, and I've worked up some "inexpensive" upgrade ideas. If I pull the heads and find that the bottom end looks OK (i.e. good cylinder walls, no obviously broken rings, etc), here is am thinking I would like to install:

GMPP Vortec heads ($279.95 each)
Summit Cam & lifter kit (P/N SUM-k1103, $69.95)
Summit Stage 1 Vortec intake manifold ($129.95)
Holley Street Avenger Carb (670 CFM) (around $350 or so)
New pushrods ($30)
New roller rockers (?)
Taller valve covers (?)

I'm still looking at rocker arms. The Summit description says that you need "self aligning" rocker arms. Can someone point me to some self aligning rocker arms? Preferably roller rockers...

Let me know what you think. Feel free to rip my choices, or give constructive criticism (preferred).

Thanks,

Mwieczorek

Gordonm

You do not need roller rockers until you start getting into roller cams and valve springs that will hold up the car. You also do not need tall valve covers. If you are on a budget save this money for something that actually makes HP. You would be better off by going to 1.6 ratio with a good roller tip than a set of roller rockers. Cam and heads are what make the power. Concentrate on matching those two with your existing short block and you will be much happier.

djcwardog

Save the $350 on the new carb and have Lars rebuild your stock one...a Rochester?

dgruenke

Sounds like a good setup overall. However, Scoggin-Dickey says that the max lift on a GMPP Vortec is .450. The Summit 1103 shows .442/.465 lift. Some companies say that the Vortecs are good to .470. You may want to check before you put it together. Scoggin-Dickey does sell a modified Vortec head with the guides machined for higher lift. Their site is www.sdpc2000.com

MWieczorek

Ok, I read the Scoggin Dickey site, it says that the stock springs are only good for 0.450" lift, but I'm pretty sure I've seen beehive springs for these heads to fix that problem.

As for my carb, my original was in pretty bad shape, it needs a rebuild. I put an auto parts store rebuilt Q-jet (the kind Lars seems to loathe) on there "for now". What does Lars charge for his rebuild service? I picked the Holley Street Avenger because I have some experience with them, and I know how to work on them. Q-jets baffle me.

I still would like to know about these special "self aligning rocker arms" that the Summit description of the Vortec heads claims you need.

Thanks, keep the suggestions coming!

Mwieczorek

bondoboy

I needed a set of rockers for my 71, and I believe they were called self-aligning. Where a stock rocker is level across the tip, these have metal that sits on each side of the valve stem, keeping the rocker straight. I got mine from gm, they are gm performance parts. The set of 16 rockers, pivot *****, and lock nuts was about $57.

Ironcross

What are vorteck heads? And why would anyone want them. Sounds like they should go on trucks. Make the case where they are better than 70 LT1`s with 202 intakes, screw in studs and guide plates.

dgruenke

It isn't the springs that are the problem, it is the valve guides. The valve stem seat hits the valve guide when you exceed the max lift. The only way to get around this is to cut the valve guides down.

You can get the self-aligning rocker arms from anywhere...eBay, summit, Jeg's, GM. They are just a different style rocker.

Little Mouse

With a low compression 72, consider the 58 cc comb. chamber
170 runner, 202/160 valves, screw in studs, S/R torquer heads
from world products. they are around $ 175.00 higher for a pair
then the vortech but you won't have to worry with a pulled
pressed in stud or low lift problems. WRL-042650-1.

Kalway

I'm running the same cam with vortec heads but I'm using a professional products cyclone intake manifold with a q-jet. I haven't tuned it in yet, but the torque right now feels like it could pull a tree out. I'm using standard $25 Z28 valve springs, though.

Once I get the carb and ignition dialed in it should be sweeeeet.

Ganey

68-72 standard hoods have limited clearance.
For Vortec heads:
New Weiand 8121 Action+. http://www.holley.com/HolleyNews/article.asp?ID=55
Summit should have a 1 1/2" drop base no name air cleaner that might help.

Roller rockers are not needed.
Full rollers are needed for about 6500+ rpm &/or when open spring pressures are over 350 lbs. to prevent galling of the ball pivot.

Edzred72

Also, your choices for an intake open up to just about anything...
Nothing wrong with vortec...I just don't care for their limitations when choosing other components.
Eddie

MWieczorek

I'm not married to the idea of running Vortec heads, I've heard good things about them, and they're affordable. I don't want to spend $1,000 on a set of heads. I took a look at those World Products heads. I've never had my heads off, so I can't be certain, but assuming the engine is in complete stock form (standard bore, stock piston, standard deck height block), what would my static compression ratio be with those 58cc heads?

I was originally looking at the Summit Performance cast iron heads. They seem like a decent deal for $325 each. Part number is SUM-152123. They have 2.02" intake and 1.6" exhaust valves with a 67cc combustion chamber. That's a definite improvement over my 76cc stock heads. Do they have pressed in or threaded rocker studs? Anybody out there running them?

Thanks gang,

Mwieczorek
:

Little Mouse

the WRL-042650-1 heads are $759.00 in summit, the 58cc comb.
chambers would be more help for a low comp engine then the 64cc
of the vortec and the 67cc of the summit heads.