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Discussion Starter #1 (Edited)
Help me out guys. I'm going to order a new set of AFR heads for my car and need help choosing the right size runners. Here's my current setup let me know if I should go with 180cc 195cc 210cc or 227cc. I know for sure I'm getting 64cc combustion chambers.

355 TRW pistons with .100 popup
block has been decked but not sure of how much
compression as of right now with my 492 angle plug heads is 12:1
Cam is a solid lifter:
Operating Range: 4000-7500 RPM
Duration Advertised: 290° Intake / 298° Exhaust
Duration @ .050'' Lift: 252° Intake / 260° Exhaust
Valve Lift w/1.5 Rockers: .536'' Intake / .554'' Exhaust
Lobe Separation Angle: 112°

Performer RPM air gap intake
650 DP with Proform mainbody
1.5 roller rockers
MSD 6AL ignition with billet distributor
3800 stall with powerglide.
4:10 12bolt posi rear
1 3/4" hooker super comps going into 2.5" V Force mufflers
Will I need to get new push rods as well? I assume yes. Thanks for any help
 

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may 09 chevy high per

you might want to read the test in the may chevy high performance mag ,, i dunno ,, the results are counter intuitive to whats considered the norm ,, but ,, i guess its true what they wrote about a 355 with a set of ported 200 dart II sportsman heads , then switched to a 235 cc world motown heads with a pretty big cam with 276 @.050 and the engine only has 11-1, and the car picked up 3 tenths in a heavy chevelle ,,,, i gotta wonder what kind of gear and converter the car had in it ,, a person would normally consider a head that big to be too big for a 355 especially with a cam like that , but it looks like it worked pretty good
 

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I'm no expert, but I've done a lot of research. It's really a question of where to you want your power range? If you plan on running the motor 6500 RPM and below and want some bottome end power, I'd go with the 180 heads. If you want more top end power and possibly spin it past 6500, then go with the 200 cc heads. I wouldn't go bigger unless you are building for lots of top end power.

Matching your cam and heads to your performance objectives is extremely important.
 

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If you're going with the AFR's, I'd look hard at the 195 Eliminators.:yes: They'd be a perfect fit for the rowdy 355.:yes:
 

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Discussion Starter #5 (Edited)
Sorry I should have added that its 25/75 street, strip use. The car has seen 7200 a couple times at the track. With my current cam I think the 210cc are the way to go but I'd like to hear what you guys suggest. I'm hoping I'll see a noticeable difference over the 492's Im running now that have been angle milled .125 and alot of port work done to them. The runners are just too small IMO.
 

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I like the suggestion of the 195 eliminator heads. I'm no expert either but i have read in a few articles that sometimes staying with a smaller runner size will help keep up the velocity of your air/fuel mix. Inturn helping you to cram more a/f into the cylinder on a N/A setup. A lot of times its more important to focus on the shape of the runner and not so much the size.
 

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Sorry I should have added that its 25/75 street, strip use. The car has seen 7200 a couple times at the track. With my current cam I think the 210cc are the way to go but I'd like to hear what you guys suggest. I'm hoping I'll see a noticeable difference over the 492's Im running now that have been angle milled .125 and alot of port work done to them. The runners are just too small IMO.
I agree, 210 or larger.
 

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The 210 Eliminators would be killer as well and leave more room to grow down the road in case you decide later to stroke it. Either way, 195 or 210, you'll have a vast improvement over what you have now!!

Yes, :yes: you'll need to measure for proper pushrod length. Different decks, installed height (possibly longer valves), etc. all adds up to different pushrods. Just bite the bullet and get the heads with 3/8" guide plates and get some Smith Brothers one piece .083" wall sticks in there.:devil: They're actually not much $different$ than the typical crap everyone else gets.

My guess is that cam (with the right valvetrain setup) will like turning a bit more rpm than you think.:yes: So getting the better pushrods will get rid of that deflection. It would probably like a set of 1.6's on the intakes as well.:D
 

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cranking pressure

be interesting to see what the cranking pressure is the motor is producing now with the 492's. The powerglide and the relatively wide LSA ( 112 ) of the cam might come into play here IMO. I watched a guy take off some 186's and go with Track 1's ( 215 runner , 72cc chamber on a 355) and slow down 1.5 tenthes. Those production heads help create alot of port velocity that might be making this package work as good as it is now.

If there was a 45-5000 converter with a 456 gear ,,, with a cam on a 104-108 LSA --260 at .050 where for sure the bigger head will do more than compliment the total package ,, ain't nothing worse than spending money and slowing down. Be interesting to see how this one turns out.

Usually most 355's that are comparible to his specs that i've read about hit they're torque peak around 4500-5000 unless they're just cammed to death for all out drag racing. I think i'd talk with several shops with dynos before i bought anything
 

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Discussion Starter #10
The current heads had all the work done by Competition Engineering and are angle milled .125. They have 2.02 1.60 valves and titanium retainers and the ports and combustion chambers have had a ton of work done to them. I think the size of the ports are 1.31 x 2.19 so they're a pretty decent size. I think they may even have titanium valves but I'm not positive.
 

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If your planning on changing cams or stroking it anytime in the near future I'd buy the 210's. Otherwise if you sticking with the same combo and not gonna change anything then go with the 195's.
 

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I recommend that you pick up the phone and ask to speak with Tony Mamo at AFR. He will set you straight on what is going to make the most power for your combination.
 

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I know a certain head porting guy who just stuck 230cc heads on his wife's 347" small block F**D cruiser!! It'll be on the dyno soon, I'm curious to see what the low speed power is like.
 

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I recommend that you pick up the phone and ask to speak with Tony Mamo at AFR. He will set you straight on what is going to make the most power for your combination.
i agree.
knowing that high stall speed, cam and header size coupled with your goal of majority strip use- id say 195-210.
personally for a 355 the 195 eliminators may be the way to go.
if you stroke it, possibly the 210's.
 

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I think you should slap a set of these babies on there!

400+ CFM
15 Degree Valve Angles
intake Valve Sizes Range From 2.150 - 2.250
Utilizes Chevrolet Spread Port exhaust Pattern
Alloy Guides
Ductile Valve Seats
Drag Race & Oval Track Specific 5 axis CNC programs.
Machined to Exacting Tolerances, Part to Part Consistency.
Cast from Virgin Alloy - A355, Unmatched T-6 Heat Treat
Requires Jesel or TD Shaft Rocker System
CNC Programs
248cc
277cc
286cc
Chamber Volumes
42cc - 72cc
Requirements
Utilizes most 18° intake manifolds
18° Spread Port Exhaust Pattern is standard. Optional Reher Morrison header adapter plates are available upon request.
Rocker arm kits are available from Jesel or T & D

And if they don't work out, just send em to me and find a home for them!!
 

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I think you should slap a set of these babies on there!

400+ CFM
15 Degree Valve Angles
intake Valve Sizes Range From 2.150 - 2.250
Utilizes Chevrolet Spread Port exhaust Pattern
Alloy Guides
Ductile Valve Seats
Drag Race & Oval Track Specific 5 axis CNC programs.
Machined to Exacting Tolerances, Part to Part Consistency.
Cast from Virgin Alloy - A355, Unmatched T-6 Heat Treat
Requires Jesel or TD Shaft Rocker System
CNC Programs
248cc
277cc
286cc
Chamber Volumes
42cc - 72cc
Requirements
Utilizes most 18° intake manifolds
18° Spread Port Exhaust Pattern is standard. Optional Reher Morrison header adapter plates are available upon request.
Rocker arm kits are available from Jesel or T & D

And if they don't work out, just send em to me and find a home for them!!
who makes these heads?!
those are big block flow numbers!
 

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Here ya go....









400+ CFM intake & 278 cfm exhaust
No other 15º head compares!


Specifications:
> A 356 T-6 Aluminum
> Ductile Iron Valve Seats
> Bronze Alloy Valve Guides
> Standard 18º Intake Manifolds
> Requires Shaft Rockers
> 52cc Chambers
> Super thick 3/4" decks
> Drilled for center Ex cooling
> HIP Processed super strong castings
> Standard GM Spread port ex pattern
> Several port sizes available
> 256,271,284,320

Assembled Heads Include:
> 2.18", 2.2" or 2.23" Intake and 1.6" Exhaust
> 1.65" Double roller valve springs
> 10º Titanium Retainers

Available Upgrades Include:
> Copper alloy seats and Titanium Valves.
> Starting at $3,600
 
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