"A Cut Above The Competition"

The following is a little information I've picked up along the way to help you in the selection of parts. 

The first build is always the hardest. Remember if you drive your car to the grocery store or a friends house, it's a street car. Everyone wants to own a Pro Street Car!  As attractive as it may seem, it is unrealistic to drive on the street. Owners of this kind of ride are heavy hitters that make more money in a day than most make in a week.  Lets get down to the basics and start from the beginning.

Once upon a time! Just kidding!

Anyone can bolt parts together, to include wrong parts. Few beginning builders realize what they have from the start. The SBC bottom end can stay together and enjoy seeing an occasional  7000 RPM spin without a problem. Within Reason!! If you pay close attention to some minor details, the mighty mouse will live on! Please remember that if you add a Nitrous Shot of 400 HP, any engine is likely to explode. The big thing is good rod bolts, a good machine shop and a little TLC during the build. Two Bolt, Four Bolt, Splayed Caps..... What do I choose? The following are recommendations that will give a little piece of mind. In all categories they are suggestions, let your pocket book guide you!

BLOCK

1. Choose a machine shop that uses state of the art equipment

2. Have the block thoroughly cleaned.  

3. Have them check for cracks. The naked eye cannot see all the problem areas.

4. Let them prep the block for assembly: freeze plugs and cam bearings. These areas require the use of special tools and if not installed properly can cause major problems. (recommended) 

5. Any build over stock should have the cylinders honed with torque plates to prevent cylinder wall distortion when assembled.

6. Over 350 HP you SHOULD have the block Full Race Prepped. (recommended)

CRANK

1. Let the build you plan guide you here.

2. To 300 HP, have it cleaned and turned/polished

3. Up to 350 HP consider having it chamfered for extra oiling

4. 400 to 450 HP (non nitrous/blown) have it chamfered and cross drilled (extra oiling) if money is available nitride the crank (strongly recommended) 

5. Over 450 HP use a forged or after market crank

These recommendations will stop the unexpected grenade effect with unplanned motors.

RODS

1. Up to 300 HP Have them checked, if they are straight USE THEM! STOCK

2. 300 to 350 install after market bolts, polish beams if money is there 

3. Over 375 please use after market rods, your motor will thank you

4. Aluminum are high maintenance items and should be used only in race motors that receive regular maintenance and are not daily driven.

5. Full race prepped steel rods work best in over 450 HP applications 

BALANCE THE ROTATING MASS!!! Find a way to afford it!! For all builds it frees up HP!

CAMSHAFT

The camshaft determines the operating RPM range of any engine. Please select carefully as you MUST match all parts to the cam profile. Bigger is not always better! If you cannot afford a new converter, gears, slicks, new intake manifold, higher compression ratio and a race exhaust system, then opt for the smaller profiles. In a street car that is daily driven, the smaller cam profiles will deliver the best tune ability (strong vacuum signal for carburetor metering) and overall performance. Pay particular attention to the recommended vehicle weight for the cam profile. 

1. Hydraulic grinds offer the most usability for a street car and offer a good vacuum signal, fuel economy and most importantly tune ability.

2. Solid grinds offer aggressive performance but require constant tinkering to keep things adjusted. You should expect to change drive train  components to match the camshaft profile. 

3. Roller grinds: Where do we start? They produce a tremendous amount of torque while allowing drivability. They offer a wide range of profiles to accommodate your every need. Larger profiles require block or rod bolt machining for lobe clearance. They also require different valve springs not to mention the original cost difference. Lastly they require changing drive train parts to match the profile. If your motor or setup doesn't match the profile, don't spend the money! If you desire professional help with your selection, LOOK HERE 

HEADS        The most overlooked hp producer!

1. Up to 300 HP use stock.

2. If you can not afford head work,  DON'T BUILD YET!!

3. Remember the larger runners you use, the higher RPM you need to turn to take full advantage of them. In a typical 300 HP SBC you only gain approximately 25 HP with larger valves. 1.94-1.50 valves keep torque in a low rpm (under 6000) motor.

4. If you are using a reputable machine shop trust their judgment in head work. If they tell you,  you need to port then port. If they tell you to install larger valves then install. But remember, they expect you to know what you need when you arrive. If you are not sure ask them, or you might pay for something you ask for, and really did not need.

5. If you are buying aftermarket heads for a strong motor, remember you may have to change things to make them work. Some require longer push rods, special gaskets or even special intake manifolds to fit their ports. Again ASK, ASK, ASK!!! "IF YOU ARE NOT SURE" tell them.  They stay in business giving the right answers. Just keep in mind, the larger the intake runner, the bigger intake charge you will need. So if you do not have a 13.1 CR, tunnel ram, roller camshaft and two 750cfm carbs, you do not require a 230 cc intake runner for a small block. Keep it all matched and it will work great.

INTAKE MANIFOLDS

Lets Get acquainted with the terminology. 180, 360 degree, single, dual plane and tunnel ram designs.

1. 180 refers to a divided plenum dual plane.

2. 360 refers to an open plenum single plane.

3. Dual plane gives the best low end torque, referring to the runner lengths being all the same distance to the cylinders (Provides low end torque). The inside cylinder runners are elevated to make the difference in length to the front and rear cylinders. The air/fuel mixture travels the same distance to all cylinders. 

4. Single plane gives a higher rpm range because the runners go straight (by direction) to the cylinders by feed. Because the runners are different lengths, the center cylinders receive a more fuel/air mixture. The front and rear cylinders require a higher rpm to equalize the distance. The piston motion (going down causes a low pressure) transfers atmospheric pressure to equalize the low pressure in the cylinder. (The term naturally aspirated)

5. Tunnel Rams. For the serious racer with a high compression engine build. If you don't have at least a 12.5 to 1 CR don't venture this way. You will not receive the full benefits and quite possibly never get the motor to run at idle with any throttle response off idle . This design requires a high compression engine. A high CR offers a low enough cylinder pressure (when the piston travels downward, naturally aspirated) for the air/fuel mixture to travel the distance. 

CARBS

There is not much to say here. Find a design you understand and TUNE TUNE TUNE!! There are 600 plus HP NHRA cars that use tuned 650 Quadra jet carbs. Please do not put a larger carb on than your application requires. If you are driving a car every day, stay with a small cfm model. If you are running a balls to the wall fire breather with high stall, tall gears and drag race only, install the larger models. Give the motor what it needs for your application. Vacuum secondary carburetors work best on the street. Find a style you understand the operation of and TUNE! TUNE! TUNE!.

HEADERS 

1. Stick with a small primary tube header for street (torque) applications.

2. With a moderate (300) HP motor use a small tube/long collector length, but keep the 1 5/8 x 3" collector model in mind. It keeps torque up in low rpm (6000 and below) applications!

3. Applications turning over 6000 RPM should use large primary tube headers

3. For high HP applications, (350,400) make sure you use tuned or equal length primary tube headers. 

4. For all out race motors over 450 HP use at least 1 3/4 in or more preferably, stepped race headers 

IGNITION SYSTEMS 

When you turn the wick up on any engine you increase cylinder pressure requiring  a hotter spark to prevent detonation and misfire at high RPM operation.

1. The points type HEI is a good unit for street operations. It can be modified up to 7000 RPM operation.

2. Dual point units deliver good performance but the points tend to bounce over 6800 to 7000 RPM

3. By far the most reliable (in my opinion) is the new breed of race distributors and ignition systems. The MSD Billet and any of their coils, multiple spark boxes and no joke wires are my favorite. But all popular brand of similar design will work well.

4. Last but not least, the crank trigger systems and magneto styles have their place but only in all out race vehicles. If you are not racing for money every weekend, please spend your money on other things.

I have also added some pictures and a few potential problems on the customers page. LOOK HERE

These are basic guidelines to aid the first time builder in the understanding of basic parts selection. If you need a complete recipe for your motors success, let CE HIGH PERFORMANCE guide you. We are the experts so you don't have to be. LOOK HERE

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