Thread: Help with Intake Manifold and rocker arms

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Hello hot rod world.
Could I possibly get some help in selecting a couple of parts for my motor.
What I have at this writing is the following;
4-bolt main 350 block--' 77-'79 era--bored .040.
Pistons are KB 11.0:1 hyperutectics.
The crankshaft is from PBM performance, with 3.48 stroke, and cast.
Heads are casting 333882; 1.94 intake, 1.50 exhaust and are in the process of being ported.
The cam I am using is from Crower with .485 lift on the intake, and .503 lift on the exhaust side, and uses solid lifters. The rpm range for this cam is approximatly 2400 rpm to 6400rpm.
The rods are "6" I-beam type.

I used the KB pistons at 11.0:1 to compensate for the fact that these particular heads I am using have 76cc combustion chambers. So, ideally I tried to get my compression ratio to about 10:1.

The questions I have are:
1. What is the recommended intake manifold to use with my setup?
2. What is the recommended rocker arm--roller tipped-- to use with my setup.
3. The heads have pressed in studs as I write this, but I am not sure whether to put a pressed in roll pin in the existing stud, or to just get a screw in stud kit somewhere and covert to screw in studs.

All parts are new; crank, rods, pistons, bearings, etc.

I am leaning towards a rocker arm from Engle/Speed Pro that has 1.5:1 ratio, longslot, roller tip for about $100, but not yet sold on it.
As far as the intake manifold is concerned, I am leaning on the Edelbrock "air gap" design, but I am not happy with the $200 price.

Can anyone offer any suggestions.
Oh, one more thing. The car will be driven on the street, but still want it strong for an occassional romp down the 1/4.
Transmission will be an automatic, with minimum 1800 stall, 3.73 rear and 15 inch tire.
Hopefully, this is enough information. I'd like to have the car ready for the next hot rod cruise festival in Ocean City, Md.

Thanks,
Mouseman

what's the part number on your KB pistons?
what's the part number on your head gaskets?
did you zero deck the block or are the pistons popped up or down in the hole or what?

Earth to mouseman, Earth to mouseman, come in please

Mouseman is back on earth. Actually, I had to format my hardrive on my computer, and reload everything.
Anyway, the P/N for my pistons are;
135-KB113040
The P/N for the H/P connecting rods are;
135-CR6001
The P/N for the rings are;
135-PS14040DS
The crankshaft-Kit-P/N is;
75000

Greg at the Napa machine shop wrote down 9.025 for the deck height of the block.

The pistons are already hung on the rods, and I am using "floating" wrist pins.

As long as we are on the subject, I will give you the P/N for the cam, lifters, and springs.

Cam; 00321
Spring; 68301x1-16
lifter; 66900-16

All three of the above are from Crower.
As you probably know, with this piston/rod combination the oil ring is positioned over the wrist pin hole. They--KB--have specific instructions on how to install the oil ring expander as well as the upper and lower oil rails. I have read the istructions several times just to make sure I don't install them wrong.

Hope this is enough information to get a recommendation on a manifold, screw in studs, etc.

Robert.

Forgot one thing.
I do not have the P/N for the head gasket yet because I do not have it yet. Can someone recommend that--head gasket--also, keeping in mind that when I port the heads, the combustion chamber volumn will probably go from 76cc to 77cc or so. I am shooting for a final CR of about 10.0:1.

Thanks.
Robert

The 7501 Air Gap RPM should work well in your application, matching the characteristics of the cam.

In my opinion, I'd go with screw-in studs and full-roller rockers instead of the cheezy half-rollers. It's your money, do as you wish.

Your crank, rods and pistons stack up to 9.001". The block is 9.025". This will leave the piston 0.024" down in the hole at TDC and won't do much for squish if you use a conventional gasket of around 0.040" thickness, resulting in a squish of 0.064". If it were my motor, I'd use a Fel-Pro #1094 shim gasket, 0.015" thickness, to put the squish at 0.039". With 731 cc's in the cylinder, 77 cc's in the chambers, 3 cc's in the gasket, 5 cc's in the deck and (negative) 3.5 cc's in the piston, your c.r. would be 9.96:1 and the motor should run well on premium pump gas with the tight squish. I'd run 12 degrees initial lead at the crank and 22 degrees of centrifugal lead, all in by 3,200 rpm's.

techinspector1, you are the man. Thanks for the in depth info, and thanks for solving my

I would like to ask you one more thing if you don't mind. I still don't have a warm an fuzzy feeling about going with the full roller rockers. I talked with Chuck at Performance Automotive Warehouse last week about this very subject, that being, is there that much of a horspower/torque difference between a full roller rocker, or a roller tip rocker. He says its minimal. What's your take on it?

Techinspector1, can you elaborate on what you mean by;

"I'd run 12 degrees initial lead at the crank and 22 degrees of centrifugal lead, all in by 3,200 rpm's."

Should I degree the cam when I put it in, or can I just put it in dot to dot?

Pardon my ignorance.

Robert

You'll free-up about 20 hp with full roller rockers over stock stamped rockers as well as lowering oil temperature and it seems to me that there is more frictional area at the stud than there is at the valve tip, so it just makes sense to me to use full rollers.

12 degrees initial refers to ignition lead or advance.

It's up to you whether or not you want to degree the cam. If you don't intend to make any changes as far as advancing it or retarding it after you have the motor running, then I don't think it's that important. There are millions of motors in operation today that never had the cams degreed in. If you will advance or retard, I think it's important to degree the cam so you know exactly where the events are occuring so you can keep accurate records of the changes you make and their results. The other reason you may want to degree the cam is to assure yourself of the quality of the cam, in other words to make certain that each valve event occurs exactly where the grinder says it will occur.

Techinstector1, have pity on me for this last question which is a continuation of the last. I learned all about centrifical, centrifugal forces in my physics classes. How does the below statement tie into the cam?
This will be my last question.

"22 degrees of centrifugal lead, all in by 3,200 rpm's."

Once again, thanks.
rob.

It doesn't have to do with the cam, it's a suggestion for the ignition. Have your distributor curved so that the centrifugal ignition curve gives a nice, even spark lead of 22 degrees over the span of 3,200 rpm's. Using an initial spark lead or ignition advance of 12 degrees at the crank and 22 degrees in the distributor will add up to 34 degrees total advance at 3,200 rpm's. You may find a little extra power playing with it a few degrees either way on the advance at the crank. I'd use an adjustable vacuum advance module from one of the aftermarket manufacturers and play with it to maximize fuel mileage at cruise. If this still is unclear to you, hunt down either or both of these books and study a little on ignition systems.....

Christopher Jacobs, 1999, Performance Ignition Systems: H P Books, 151 p.

Todd Ryden, 2004, How to Build High-Performance Ignition Systems - For Domestic and Import 4, 6, and 8-Cylinder Cars: S-A Design, 128 p.

While I am a mere hobbyist, there are members on this board who do this professionally. May God have mercy on their souls

Rob, you don't need to feel sheepish about asking questions, all of us had someone who helped us learn this silly hobby and pointed us in the right direction.

Many thanks for the suggested books.
Speaking of distributors, Can I get away with using a Mallory dual point with vacuum advance? I don't have it yet, but that is what my intention was.

P.S. While I have worked on cars as a hobby for a good chunk of my life, this is the first time I am actually building the entire motor myself from crank to carb.

Yes, you can "get away with" a points distributor. The strong point of them is fixing them on the side of the road with a new set of points and a condenser that you keep in the glove box.

The flip side of the coin is the "zero maintenance" afforded by an electronic distributor or a conversion from points to electronic with units such as the Pertronix.

Personally, I'd use a stock Chevy HEI before I'd buy a points distributor, then just carry extra HEI parts in the glove box.

Performance Distributors in Memphis has a good business going, altering HEI units and tailoring them to the customer's needs.....
http://www.performancedistributors.com/

Many thanks.

"Your crank, rods and pistons stack up to 9.001". The block is 9.025". This will leave the piston 0.024" down in the hole at TDC and won't do much for squish if you use a conventional gasket of around 0.040" thickness, resulting in a squish of 0.064". If it were my motor, I'd use a Fel-Pro #1094 shim gasket, 0.015" thickness, to put the squish at 0.039". With 731 cc's in the cylinder, 77 cc's in the chambers, 3 cc's in the gasket, 5 cc's in the deck and (negative) 3.5 cc's in the piston, your c.r. would be 9.96:1 and the motor should run well on premium pump gas with the tight squish. I'd run 12 degrees initial lead at the crank and 22 degrees of centrifugal lead, all in by 3,200 rpm's."

Do I need to use any kind of sealer on the above recommended gasket--Fel-Pro #1094--when I put it on or can I just put in on dry, and then lay the head on top of it, and torque it to spec?