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Discussion Starter #1
I seem to need a new head...Ok here is the engine. 383 sbc all forged rotating mass. 144 Holly blower putting around 6 lbs of boost, 18 cc "D" disked pistons, Comp hyd flat tappet blower cam.

Valve Lift @ 1.5:1 in. .462 ex. .480

rocker arms are Stamped steel roller tip. 1.6:1 ratio

Duration

Adv. @.050"
In. Ex. In. Ex.
262 280 218 230

RPM Range
1600-5900

Lobe Sep. Angle 113*


Will be used on street and road track...

So what are my best head choices. AFR, Brodix, Edelbrock, other? What size int. runner.

I know I want 2,02" int. and 1.6" ex. valves. And I need 76 cc chambers to maintain 8.5:1 compression ratio.

What are your thoughts, ideas, what worked for you.

Looking for lots of discussion on this...
 

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I saw the head in the other thread. It doesn't look too bad. Can't you have it welded?
 

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All good suggestions in the above

Trickflow Does'nt make anything for the car ?

AFR's would be my other choice

Call Charlie at http://www.rpm-motors-inc.com/

This guys shop is Full race cars

All of them corvettes

he has an in With Tony at AFR

They are friends and Charlie is an Honest guy
 

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i dont have any experience with the new trick flow heads, i know their old "twisted wedge" series was pretty damn good, and their nextgen LS series heads make more power than afr heads, so....
 

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Discussion Starter #8
Ok now for some more questions...

1. What is the advantage of angled vs straight plugs?

2. How big can I go on the intake runners with out looseing low end torque?

3. Who will give me the money to buy these heads?:D
 

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1. header clearance.

2. since you are supercharged, the ports can't really be too large- within reason. since it really isnt a huge blower and the cam doesnt have a ton of lift, 235cc would probably be as big as i would go.

3. first national bank of patrick


since you are pulling the top of the engine off, just might be the perfect time to do a cam swap and really wake it up. :devil:
 

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Discussion Starter #12
1. header clearance.

2. since you are supercharged, the ports can't really be too large- within reason. since it really isnt a huge blower and the cam doesnt have a ton of lift, 235cc would probably be as big as i would go.

3. first national bank of patrick


since you are pulling the top of the engine off, just might be the perfect time to do a cam swap and really wake it up. :devil:
Thanks for the info.

I don't want to go any larger in the cam department. I want to keep its good manners and 17 plus MPG on 87 octain for road trips.
 

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Discussion Starter #14
Well I am thinking about

AFR 1038 heads

SB-Chevy Street Cylinder Head
195cc Intake Ports
L98 Type Angle Plug
75cc Combustion Chambers
64cc Exhaust Ports
1.290'' OD Hydraulic Dual Valve Spring
135bs. Seat Pressure
.600'' Max Lift
2.02" intake valve
1.6" exhaust valve

Whats every one take on these heads??? Pros...Cons?
 

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2. since you are supercharged, the ports can't really be too large- within reason. since it really isnt a huge blower and the cam doesnt have a ton of lift, 235cc would probably be as big as i would go.

......


since you are pulling the top of the engine off, just might be the perfect time to do a cam swap and really wake it up. :devil:


it does absolutely no good to place a cylinder head with with a port cross sectional area thats larger than the intake port that feeds it,beyond the intake runner exit, in a combo as all the abrupt increase in port cross section does is cause increased turbulence, and a sudden loss of port air flow speed and that tends to cause fuel to drop out of the airflow or at least disrupt is even distribution
in an ideal world ports reduce cross sectional area bye about 3% from entrance to the valve pocket, and the port cross section in the heads a bit smaller than the intake runner.
the port flow is limited by the ports smallest cross section not its largest

http://www.wallaceracing.com/max-rpm2.php
http://www.rbracing-rsr.com/runnertorquecalc.html

cams need to be selected with the engines intended rpm range and power band and the displacement of the engine, plus the engines compression ratio and drive train gearing taken into account, any increase in port cross sectional area above whats required to fill the cylinders in the intended power band tends to reduce efficiency.

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=322

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=2782&p=7214#p7214

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=796&p=1156#p1156

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=333&p=407#p407


 

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grumpy, i know that if the port on the head is larger than the port on the intake it will actually hurt flow. i guess it is my fault for assuming it is common knowledge to always port match your intake and head.
 

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grumpy, i know that if the port on the head is larger than the port on the intake it will actually hurt flow. i guess it is my fault for assuming it is common knowledge to always port match your intake and head.
keep in mind that most of my posted responses, are posted assuming the readers have some interest and mechanics skill but some where between minimal and average mechanical skills so I tend to post the basics knowing that the more experienced guys will know whats required

btw
http://forum.grumpysperformance.com...2773&p=7200&hilit=gasket+porting+intake#p7200

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=462


http://forum.grumpysperformance.com/viewtopic.php?f=55&t=2773&p=7802#p7802
 

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Discussion Starter #18
Well I ordered the AFR 195cc SBC Street Cylinder Heads. Thanks for all the input. Will keep you updated on the install.
 

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Discussion Starter #19
Well I have the AFR heads installed and drove it today. :thud:

I don't need low gear any more... Runs just fine starting in second.
 

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Well I have the AFR heads installed and drove it today. :thud:

I don't need low gear any more... Runs just fine starting in second.
:devil:

pics! We want pics and vids! :excited:

did you finally get your brake parts or did you just thrown the old ones back on for now?
 
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