Larger Intake Valve Cylinder Head Work - ZR-1 Net Registry Forums

Jagdpanzer · 10-23-2017

For the 427 build I have underway will be going with 41.9 mm intake valves to increase air flow for feeding the the additional displacement. Here are a few photos of the work in progress for fitting the larger valves:

Target combustion chamber size is 43.6cc which results 12:1 static compression ratio. For comparison stock combustion chambers run around 39cc. The "clover leaf" shape of the stock chambers severely shrouded the larger intake valve and was removed to allow for better airflow, especially at lower cam lift. Also radiused the area around the outside of the exhaust valves to take full advantage of the larger cylinder bore diameter.

Roadster · 10-23-2017

You do amazing work Phil.....great to have that talent to perform those tasks....will be anxious to see and hear the results of your build.....

jss06c6 · 10-24-2017

Does anyone know if a 3D solid works (or similar) file exists for the LT 5 head? Would be very useful for designing modifications..

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tpepmeie · 10-24-2017

Excellent Phil. Looks like the Gen III chamber a bit. Hope the airflow numbers meet your target too.

FU · 10-24-2017

That's the ticket

What metal seats will you be using ?

Jagdpanzer · 10-24-2017

Seats are a tungsten alloy from Tucker.

BigJohn · 10-24-2017

Any loss of torque?

Jagdpanzer · 10-24-2017

Should have plenty.

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oricale · 11-01-2017

Looking great!

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XfireZ51 · 11-02-2017

FourTwentySeven. Has a nice ring to it.

10-23-2017	#1
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Larger Intake Valve Cylinder Head Work For the 427 build I have underway will be going with 41.9 mm intake valves to increase air flow for feeding the the additional displacement. Here are a few photos of the work in progress for fitting the larger valves: Target combustion chamber size is 43.6cc which results 12:1 static compression ratio. For comparison stock combustion chambers run around 39cc. The "clover leaf" shape of the stock chambers severely shrouded the larger intake valve and was removed to allow for better airflow, especially at lower cam lift. Also radiused the area around the outside of the exhaust valves to take full advantage of the larger cylinder bore diameter. __________________ Phil Wasinger 1994 Torch Red ZR-1 WAZOO Member George Braml Intake

10-23-2017	#2
Roadster Join Date: Mar 2014 Location: Warrington PA Posts: 1,914	Re: Larger Intake Valve Cylinder Head Work You do amazing work Phil.....great to have that talent to perform those tasks....will be anxious to see and hear the results of your build..... __________________ Tom 1994 ZR-1 #009 "captured test fleet car" 1974 LS4 454 Vert 1974 L-82 355 Vert. 1982 L83 CFI...now a retired "dd"....Sold WAZOO Member

10-24-2017	#3
jss06c6 Join Date: Aug 2015 Location: Magnolia, Texas Posts: 884	Re: Larger Intake Valve Cylinder Head Work Does anyone know if a 3D solid works (or similar) file exists for the LT 5 head? Would be very useful for designing modifications.. Sent from my XT1585 using ZR-1 Net Registry mobile app

10-24-2017	#4
tpepmeie Join Date: Aug 2005 Location: Fishers, IN Posts: 815	Re: Larger Intake Valve Cylinder Head Work Excellent Phil. Looks like the Gen III chamber a bit. Hope the airflow numbers meet your target too. __________________ Todd ____________________________________ *** our email address has changed! info@pepmeierengines.com pepmeierengines.com Friend us on Facebook too: www.facebook.com/profile.php?id=100011443683384 Pepmeier Engine Development

10-24-2017	#5
FU Join Date: Mar 2004 Location: Found Member Posts: 4,346	Re: Larger Intake Valve Cylinder Head Work That's the ticket What metal seats will you be using ? __________________ Frank Urbo. NCM Lifetime member # 982 Registry Founding # 237

10-24-2017	#7
BigJohn Join Date: Feb 2012 Location: Ledyard,CT Posts: 8,242	Re: Larger Intake Valve Cylinder Head Work Any loss of torque?

11-01-2017	#9
oricale Join Date: Oct 2011 Location: STAFFORD VA, Posts: 576	Re: Larger Intake Valve Cylinder Head Work Looking great! Sent from my SM-G955U using ZR-1 Net Registry mobile app __________________ [B][I][COLOR=red]1990 ZR1[/COLOR][COLOR=black] [U]#00077 [COLOR=red]RED[/COLOR]/[COLOR=red]RED[/COLOR] (10Y022 PEP CAR) [/U][/COLOR][/I][/B][B][I][COLOR=red]1991 ZR1[/COLOR][COLOR=black] [U]#00517 ("Irene")[COLOR=red]WHITE[/COLOR]/[COLOR=red]RED-SOLD:cry:[/COLOR] [B][/B] [/U][/COLOR][/I][/B][B][I][COLOR=red]1992 ZR1[/COLOR][COLOR=black] [U]#00445("The Revenant")[COLOR=red][COLOR="Black"]BLACK [/COLOR][/COLOR]/[COLOR=red]RED(2016 T.O.D!) [/COLOR] [/U][/COLOR][/I][/B] [B][I][COLOR=red]2009 [COLOR=red]Z06!![COLOR=black]BLK/BLK rare Linen interior[/COLOR] 707HP!![/COLOR] [/COLOR][/I][/B] [B][I][COLOR=red]2006[/COLOR] BLK/BLK Z51 (Just SICK FAST!)SOLD)[/I][/B] [B][I]1996 BLK/BLK LT4 Grnsprt(sold...Twice!)[/I][/B] [B][I]1991 RED/REDL98(Fell off the shipping truck:([/I][/B] [B][I]1980 BLK/RED L82(Sold)[/I][/B] [B][I][B][I]1990[/I][/B] RED/BLK(sold.....In Japan)[/I][/B] [I][COLOR=black][B][I]2006[/I][/B][/COLOR][/I] [COLOR=red]Mustang GT[/COLOR] ([B][I]mach 1[/I][/B])[B](sold)[/B] [COLOR=black][B][I]1969[/I][/B][/COLOR] [COLOR=red]Mach[/COLOR] [B][I]1(sold in Japan)[/I][/B] [COLOR=black][B][I]1969[/I][/B][/COLOR] [COLOR=red]Mach[/COLOR] [B][I]1#2(sold)[/I][/B] [B][I]WAZOO Member...[/I][/B] [url]www.evolution-motorsport.com[/url] facebook/evolutionmotorsportengineering Your Local [url]www.Amsoil.com[/url] dealer/user.. Victory Loves Preparation

11-02-2017	#10
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,707	Re: Larger Intake Valve Cylinder Head Work FourTwentySeven. Has a nice ring to it. __________________ [SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX