Ported Chevy 081 heads 305 version
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Re: Ported Chevy 081 heads 305 version
I'm really enjoying the info. Keep up the good work.
Everyone appreciates your honesty , until you're honest with them , then you're an @$$hole.
Re: Ported Chevy 081 heads 305 version
I think we figured it out with a "how did he do that"
honest bench- what's not to like
honest bench- what's not to like
Re: Ported Chevy 081 heads 305 version
What kind of power can you make out of a 305 with these ported 081's? 240-250 cfm is good flow for a small bore smaller valve head
Re: Ported Chevy 081 heads 305 version
The flow would be down from these. These have been opened up to a 350 bore size. As a guess I would say subtract 20 cfm intake and 12 exhaust. But 220 cfm if it would flow that I bet could make nearly 400 hp with the right combo. I know on a 306 Ford with about that flow it was a tranny breaker.Orr89rocz wrote:What kind of power can you make out of a 305 with these ported 081's? 240-250 cfm is good flow for a small bore smaller valve head
Servedio Cylinder Head Development
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Re: Ported Chevy 081 heads 305 version
Even a stock untouched 305 head like the 081 or the 4416 the chamber overhangs the 305's small bore, so
just stick it on a go. With the 1.94 valve it is going to to work well. Of course boring the cylinders bigger +.040" say on a 305 is just sweetening the pot. I can see you getting a strong 230+cfm when tested on a 3.736" bore fixture.
And would also work well on a 307 or a 283 or a 350 budget motor.
Most of the chamber gains are your work near the spark plug which are good to go on the smaller bore too.
It would be nice to see your head tested on such a motor.
I think your chamber has a advantage over the 4416 chamber with better plug position and chamber shape in your modded form.
What's important on these smaller cid sbc motors is to not under build them. EG: Oh its only a 305 how could it ever need more than a 600 carb" Not enough compression ratio, small carb small manifolds. You want to avoid the tendency to dummy it down.
Wind it up a bit and Let it eat and you'll be surprised. "Letting it eat" starts with the cylinder head.
just stick it on a go. With the 1.94 valve it is going to to work well. Of course boring the cylinders bigger +.040" say on a 305 is just sweetening the pot. I can see you getting a strong 230+cfm when tested on a 3.736" bore fixture.
And would also work well on a 307 or a 283 or a 350 budget motor.
Most of the chamber gains are your work near the spark plug which are good to go on the smaller bore too.
It would be nice to see your head tested on such a motor.
I think your chamber has a advantage over the 4416 chamber with better plug position and chamber shape in your modded form.
What's important on these smaller cid sbc motors is to not under build them. EG: Oh its only a 305 how could it ever need more than a 600 carb" Not enough compression ratio, small carb small manifolds. You want to avoid the tendency to dummy it down.
Wind it up a bit and Let it eat and you'll be surprised. "Letting it eat" starts with the cylinder head.
Re: Ported Chevy 081 heads 305 version
I have done a bunch of these, very similar to 083's. Long Island's drag stirp was closed so I don't have any numbers. These were nice on 383 or 355 with a decent flat tappet of hydraulic roller cam. Good torque and pull to about 6- 6500 rpm. Better than you would think for a throw away head.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
631-816-4911
9:00am - 9:00pm EST