Thread: SBC Heads

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I'm in the planning stages of building my next SBC 350. My question is, I'm looking for a set of heads that will give me some good street performance . I'm going with a full roller cam, nothing to big Comp 224/230 degree hydraulic roller performer rpm intake ( May be smaller ), edelbrok 600 cfm carb and headers Msd ready to run dist, 700r4 trans with 373 gears. 17" wheels.
I,m looking for suggestions on a decent set of heads that would be good for street performance, It will never see the track. Are the Vortec Heads as good as RHS, Pro Comp, etc, good for my application. I do not want to spend $1,500 on a set of heads that will not fit my needs.

you might want to try edelbrock. they have excellent products and decent prices. they can match your setup with the correct heads to use.

Originally Posted by Jim Standley

I'm in the planning stages of building my next SBC 350. My question is, I'm looking for a set of heads that will give me some good street performance . I'm going with a full roller cam, nothing to big Comp 224/230 degree hydraulic roller performer rpm intake ( May be smaller ), edelbrok 600 cfm carb and headers Msd ready to run dist, 700r4 trans with 373 gears. 17" wheels.
I,m looking for suggestions on a decent set of heads that would be good for street performance, It will never see the track. Are the Vortec Heads as good as RHS, Pro Comp, etc, good for my application. I do not want to spend $1,500 on a set of heads that will not fit my needs.

I would try a set of the 180 cc Dart Iron Eagle heads.
I would keep the RPM Performer.

Eric, 64 or 76 cc ?

Originally Posted by Jim Standley

Eric, 64 or 76 cc ?

64 cc's with the 350 engine will work fine.
A flat top piston like a Speed Prp L2256f will give you 9.75 to 1 for a comp ratio with 64 cc heads.

The valves won't make much of a difference to the performance on a street engine. At low lift the shrouding on the long side turn out of the intake runner is higher, so airflow will actually be decreased with a BIGGER valve. Big valves only help on higher lift applications or on high-RPM applications where fast, high volume breathing is required. If you're not planning to race it I would stay with the smaller valves, they also leave more material between the valves, where most head cracks appear. Chose a good chamber shape and valve seat shape (maybe try a 30° seat, good for low-lift flow), almost all of the large chamber heads have open chambers with less quench area (that's where the chamber is flat and parallel to the piston and thus squeezes mixture into the main chamber on the compression stroke, this puts off detonation. That's generally not good for performance.
But a couple of questions:
What RPM are you aiming at?
What HP do you want to reach?
Really only street?
How heavy is the vehicle?
Are you interested in mileage?
When we know this we can give you a bit of a better estimate on the heads you want to use. And don't forget, the parts most crucial to performance are heads and cam, and they have to match up nicely. It's easy to get an engine to starve at 3500 RPM, manage 8mpg and reach 200 ftlbs of torque with a set of $ 2.000 heads... But it's also possible to get 300HP out of a set of $ 50 rebuilt junkyard heads, if you match the crucial parts together nicely...
Give us some more info and we'll give you some more help
Max

Originally Posted by MadMax

The valves won't make much of a difference to the performance on a street engine. At low lift the shrouding on the long side turn out of the intake runner is higher, so airflow will actually be decreased with a BIGGER valve. Big valves only help on higher lift applications or on high-RPM applications where fast, high volume breathing is required. If you're not planning to race it I would stay with the smaller valves, they also leave more material between the valves, where most head cracks appear. Chose a good chamber shape and valve seat shape (maybe try a 30° seat, good for low-lift flow), almost all of the large chamber heads have open chambers with less quench area (that's where the chamber is flat and parallel to the piston and thus squeezes mixture into the main chamber on the compression stroke, this puts off detonation. That's generally not good for performance.
But a couple of questions:
What RPM are you aiming at?
What HP do you want to reach?
Really only street?
How heavy is the vehicle?
Are you interested in mileage?
When we know this we can give you a bit of a better estimate on the heads you want to use. And don't forget, the parts most crucial to performance are heads and cam, and they have to match up nicely. It's easy to get an engine to starve at 3500 RPM, manage 8mpg and reach 200 ftlbs of torque with a set of $ 2.000 heads... But it's also possible to get 300HP out of a set of $ 50 rebuilt junkyard heads, if you match the crucial parts together nicely...
Give us some more info and we'll give you some more help
Max

With the hyd. roller cam is running I would look into after-market heads based on the lift and duration.
If he runs with stock heads I would guess he would give up 30-40 hp.

the cc of the head chamber would have to do with the pistons you run for what you want to see for cr the iron eagles or the pbm iron heads of 180intake cc should be ok

If I went with the 64cc what are the advantages of having the larger 202/160 valves compared to the smaller 194/150 valves ?