Those with ported heads, enter hear.

[Polecat Z]

Well, I posted this question in the LT1 forum but was unsuccessful at getting any usable information. I'm in the process of porting my LT1 heads. I also have Hooker LT's. I looked over Nuke61's website and DIY head porting page(VERY helpful and informative BTW) He used the 1406 header gasket to port his heads to. It seems this is the most popular header gasket for our applications. I picked up the 1406 gasket and the 1470(LT1/LT4 specific) gasket for comparison. The 1406 gasket is a fair amount larger than the port opening of my headers. The 1470 is about the same size as the header port.
Now obviously, I want to port my heads for maximum flow and power. If I port my heads to the 1406 gasket, will my efforts be wasted when they exit into the smaller header port? Ken Mook posted he used the 1406 gasket, but didn't go into how it fit his ports(does it fit your heads port? Is it larger than your heads port?). I know that most of the heavy hitter LT1's use the Hooker LT's, and most of them MUST have ported heads. So guys, give me some heads up here.

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Jamie Taylor
'94 Z28 M6
Mods: BBK 52mm TB, Granetelli MAF, MSD 8.5 wires, MSD coil, Bosch +4 plugs, gutted cat., In the final stages of HOT cam kit, ported heads, CSI H20 pump, Jet Hot Hooker LT's(thanks to the GP), custom 3" Y-pipe, and Custom CAI installations. It's nice being a welder, I can do all this custom tubing stuff easy!!!
1971 Datsun 240Z with V8 power. 500+rwhp

[kmook]

hmm, never really looked at it. I do have ported heads and hooker LTs, and as you said i used the 1406's. I am not sure about how it lines up as i never really paid attention. My new set of heads goes on next weekend so i could let you know then if no one else does, but i'm sure other people know...

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Ken Mook - 97' SS #2544
Advanced Tech Posting Guidelines

• Almost Alive: ?rwhp & ?rwtq Naturally Asperated on the Stock Bottom End.
• Stage 3 Pro Performance Heads, Solid Roller 242/248 Cam, Jesel Shaft Mount Rockers,
• Jet Hot Hooker LTs, True Dual 3" Exhaust with x-pipe, and the list goes on and on...

[JordonMusser]

you DO NOT match to the gasket...

gasket is just a loose reference.

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-94 Black T-Topped Z28 M6, 10s, and daily driven!
-96 CBR F3, modded of course
-92 Talon Tsi AWD, also too many mods..
-99 Tony Kart
http://www.fastblackcar.com

[Polecat Z]

I know not to port it out to match the gasket. The port floor is about 1/4" lower on the 1406 than the port floor of the head. Does anyone have pictures of there ported heads on the web? I don't have a couple sets of heads or a flow bench to experiment with, so I have to get it right the first time.

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Jamie Taylor
'94 Z28 M6
Mods: BBK 52mm TB, Granetelli MAF, MSD 8.5 wires, MSD coil, Bosch +4 plugs, gutted cat., In the final stages of HOT cam kit, ported heads, CSI H20 pump, Jet Hot Hooker LT's(thanks to the GP), custom 3" Y-pipe, and Custom CAI installations. It's nice being a welder, I can do all this custom tubing stuff easy!!!
1971 Datsun 240Z with V8 power. 500+rwhp

[strokedTA]

Just polish the ports.
That's all you need right now, from the way it sounds.
No point in making them any bigger with such tiny headers.

Good luck,
Dave Brown (2" headers)

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If a little's good,
More is better,
And too much is just right!!!

[JeffSTAR]

Not only do you not port match to gasket you may have missed the point that the intake and exhaust runner don't determine flow like you think they would at first. There are other restrictions in the head that are going to flow much less then the intake runner could possibly flow in stock trim. The pocket, throat and bowl/combustion chamber transition is where you need to concentrate. Also, the higher the flow with a smaller runner, the higher the velocity in most cases, which is ideal for a car spending time at low to mid RPMs, like a street car.

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Jeff Collop
<A HREF="http://collop.cz28.com" TARGET=_blank>Supercharged 95 Z28 SixSpeed
390 rwhp / 380 rwtq N/A
520 rwhp / 564 rwtq N2O
XXX rwhp / XXX rwhp BOOST
Stock Short Block</A>

------------------------

"...in our lifetime those who kill, the News World hands them stardom, and these are the ways on which I was raised, these are the ways on which I was, which I was raised; I never wanted to kill I am not naturally evil, such things I do just to make myself more attractive to you..." - Steven Patrick Morrissey

[This message has been edited by JeffSTAR (edited July 02, 2002).]

[Polecat Z]

The improvements made in the bowl, combustion chamber, and throat are not at question. I know the benefits of massaging the heads in those locations. Infact, way more time has been spent in the bowls an throat, than in the actual port itself. As well as smoothing out the combustion chambers. Thats why I didn't ask "How do I port my heads". I was just trying to figure out why everyone uses the 1406 gasket.(there must be a good reason). The 1470 gasket is a much better match to the port than the 1406. On Nuke61's page, he mentioned he used the 1406 gasket to port his heads to(though not lowering the ports floor too much). All of the other advise on his page has been good, and I thank him for sharing his information with everyone.

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Jamie Taylor
'94 Z28 M6
Mods: BBK 52mm TB, Granetelli MAF, MSD 8.5 wires, MSD coil, Bosch +4 plugs, gutted cat., In the final stages of HOT cam kit, ported heads, CSI H20 pump, Jet Hot Hooker LT's(thanks to the GP), custom 3" Y-pipe, and Custom CAI installations. It's nice being a welder, I can do all this custom tubing stuff easy!!!
1971 Datsun 240Z with V8 power. 500+rwhp

[ToddR]

What's nuke61's web page address?

[Polecat Z]

http://members.cox.net/gmarengo/ I found this Nuke61's site to be very informative and he gave good advice.

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Jamie Taylor
'94 Z28 M6
Mods: BBK 52mm TB, Granetelli MAF, MSD 8.5 wires, MSD coil, Bosch +4 plugs, gutted cat., In the final stages of HOT cam kit, ported heads, CSI H20 pump, Jet Hot Hooker LT's(thanks to the GP), custom 3" Y-pipe, and Custom CAI installations. It's nice being a welder, I can do all this custom tubing stuff easy!!!
1971 Datsun 240Z with V8 power. 500+rwhp

[nuke61]

I found this Nuke61's site to be very informative and he gave good advice.

If you're talking about other parts of my website, thanks, but just to clarify, any kudo's about the head porting should be directed to Mike Henkel. As I said at the top of the DIY Head Porting page, "Courtesy of Mike Henkel, aka Mikey 97Z M6 on www.cz28 - Mike supplied the writeup and the pictures, and I supplied the host site and reformatted it as I saw fit.

All I did was post the information he provided me and added the tiny bit of information about the teardrop shape of the guide bosses as suggested in David Vizard's "How to Build & Modify Chevrolet Small-Block V-8 Cylinder Heads" with a picture of Jordon Musser's AFR heads showing what I was referring to.

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Hear LT1 cam WAVs, DIY head porting: members.cox.net/gmarengo

'95, !CAGS, CAI, ForceII, Hooker Shorties, 14.2@103

[Ed95Pont]

I have had a very tough time getting the 1470 gasket to seal.I have also tried their copper gasket with the same opening as the 1470.They leak also.
Change to 1406 and no problems.

The 1470 leak from the top .

Ed

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95 Formula Solid Roller 9 Inch 4.10 H.D. Locker,6 speed
Best 1/4 12.074 Best MPH 115.56 on STOCK HEADS


94 Hardtop Heads up Drag car


94 Formula A4 Stock
120,000 miles 13.82

Tow Rig 84 suburban 3/4 4wheel drive 388 small block

[Dr.Mudge]

Its just a gasket that works fairly well, there is nothing special about its dimensions that has anything to do with porting.

As noted the runners are not really a restriction, and dont touch the floor other than casting flash.