[LT4USMC]

I'm finally building Badbird69 (474cid CP piston, R&R rod, 4.25") assembly I bought from him some years back. Looking for heads. Car is 71 Bird setup for road racing similar to Bollinger race car so velocity/throttle response preferred over huge flow numbers. Can I get High Ports under shaker hood? Thanks in advance hope to be playing at the Curcuit of America's here in Austin TX soon.

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[Dragncar]

IMO, you are better off with a nice set of the new E heads with CNC chambers. To even have a shot at running a shaker hood you will have to run a Northwind intake. Maybe a T2 but you engine is a little too large for one. Chopping a Victor down to fit costs some power.
There will be a price to pay running High Ports on a shaker hood. More intake options, air cleaner options with E heads and you can easily get them to preform better than the HP versions you are talking about.

[ErikW]

Performer RPM can be used with a shaker and some air cleaner mods. Probably a better intake for road racing anyway.

[LT4USMC]

Originally Posted by ErikW

Performer RPM can be used with a shaker and some air cleaner mods. Probably a better intake for road racing anyway.

ErikW for the record, I spoke to Jeff Kauffman at length and he has numerous second gen Trans Ams out there with the High Ports and a Northwind under a dropped shaker setup. That is the route I took as well. As cast Hi Ports with a 246/258 600 on 114 good for + or - 640hp on pump gas

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[Steve C.]

A fwiw. On the Year One Bandit Trans Am project with a 535 combo Jim Butler used a Victor intake with the carb flange milled down 0.650" to help it fit under the hood. With the cut down intake he used a WFO drop base unit for the TA Shaker scoop in conjunction with Edelbrock heads. Tested on the engine dyno at peak power rpm it gave up about 15 HP by milling the intake. On my current 505 street engine I did the same thing with a Victor intake & HP950 carb. On the dyno I lost about 8-10 HP at peak power rpm after milling the intake flange 0.650". Not a race deal so for me I did not miss the 8-10 HP. Now how much does it effect lower RPM torque I'm not certain without going back and looking at dyno sheets.... but I'll assure you when dealing with 600+ horsepower it certainly would not be a big deal regarding the torque loss. Again for me street use, on a road coarse I do not have the experience to make assumptions.

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[Steve C.]

Stated by the OP:

"....so velocity/throttle response preferred over huge flow numbers."

Regarding that subject, unless changed the High Port heads as cast have about a 277cc intake runner volume. Now compare that to the Edelbrock head as cast.
From my personal experience my Edelbrock heads done many years ago had about a 236cc intake runner volume and were approaching 330 cfm at .700" lift.

Another subject to consider is the High Port head uses a large 2.200" intake valve with a taller installed height, thus a longer stem length. Something to consider when evaluating the spring pressure to control the valvetrain weight involved.

No big deal, just a fwiw tid bit. As cast the intake ports are taller than Edelbrock heads. A typical gasket used on the as cast High Port head would be about 2.320" tall.

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[ponjohn]

Originally Posted by LT4USMC

ErikW for the record, I spoke to Jeff Kauffman at length and he has numerous second gen Trans Ams out there with the High Ports and a Northwind under a dropped shaker setup. That is the route I took as well. As cast Hi Ports with a 246/258 600 on 114 good for + or - 640hp on pump gas

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Did your engine dyno at this power level?
What cubic inch?

[Steve C.]

474 CID / 4.250" stroke with as cast High Port heads using a 246/258 cam with 0.600" valve lift making 640 HP ?

I'd like to see some examples posted. Not a guess, confirmed numbers from a dyno session.


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[Steve C.]

KRE HIGH PORT HEAD...

"Out of the box heads make 628 tq and 700 HP on a 463 CID engine"

The problem with this example, NOTE... no cam stated or compression ratio. What intake involved ?

http://www.spottsperformance.com/heads.htm

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[Steve C.]

Another tid bit.... Not suggesting they are needed for the goal here but if the conversation swings towards the use of Butler Wide Port Edelbrock heads they require offset shaft rockers and offset lifters, thus the use of a solid roller cam only.


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[LT4USMC]

Man, I remember when Bruce Fulper was on this forum in the 90's and ran people off with the same type of "knowledge". I'm finding it happening again... thanks for the help Cliff, Dave,Jeff, and Dick (Badbird69)! Into the fire I go...

It is 10.9 static and 8.6 dynamic if you pay for dyno time you can have all the data you want. You and half a dozen others on here take the fun away from conversation. Almost like talking to someone radically left or right on their political views. Rather than saying hey there is someone trying something new and having a helpful hand out to help continue and grow our livelihood or hobby you tare people to spreads. For the record I 'm actually putting this on the street, aluminum rods and all. She's good to 7500rpm ask Dick. Heads as cast flow enough for 650hp ask Jeff. Cam selection is good for what I say, ask them all. I'm sick of trolls and mouth running. I'll be on the toll road where it's legal to do 85MPH headed to Alamo Raceway for some fun then back home to run Curcit of the America's the next day for more fun. Which is the name of the game whether for money or personal gratification FUN!

4.221 bore
4.25 stroke
6.8 rod R&R aluminum
80cc Hi Port as cast 330cfm range
Cam: SR 246/258 @0.50 .597 lift on 114lsa
Intake: Northwind 4150 w/ AED 950HO carb
Fuel Pump: Weldon 2311 w/Weldon bypass reg, deadhead reg, and 14000 Controller
640hp + or - pump gas
T56 Magnum
3.73 currently will be going to 3.55 maybe 3.23 when it breaks
26" tire

All while sipping a Slurpie!
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[LT4USMC]

Originally Posted by Steve C.

Another tid bit.... Not suggesting they are needed for the goal here but if the conversation swings towards the use of Butler Wide Port Edelbrock heads they require offset shaft rockers and offset lifters, thus the use of a solid roller cam only.





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Just like I did when the Edelbrock was new technology, I'm moving forward to a totally new design with the High Port

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[LT4USMC]

Originally Posted by ponjohn

Did your engine dyno at this power level?
What cubic inch?

See long post...

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[Steve C.]

Please don't misunderstand my posting, I'm not suggesting you not use the High Port heads. At the same time I mis understood and did not know you already had them and were in use.

I'm just passing on relevant information for conversation. The set of High Port heads I purchased and had ported here in Texas made 0ver 900 HP.

And keep in mind some might stroll thru here and learn something new they did know about High Port heads.

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[PAUL K]

A lot of good information in the posts above. Please let us know how the Hi-ports fit under the shaker scoop. Good luck with your build!

[LT4USMC]

Originally Posted by Steve C.

Please don't misunderstand my posting, I'm not suggesting you not use the High Port heads. At the same time I mis understood and did not know you already had them and were in use.

I'm just passing on relevant information for conversation. The set of High Port heads I purchased and had ported here in Texas made 0ver 900 HP.

And keep in mind some might stroll thru here and learn something new they did know about High Port heads.

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Steve, I truly appreciate your clarification and hope we all can continue to contribute in a meaning full way to keep the Pontiac alive in the veins of the new comers. I plan to post things as they happen the good ,the bad, and the ugly...

Where are you located? As you see this is a .060 over 455 so when it goes I too will more than likely going to aftermarket block. This also why I went with High Ports for room to grow.

I'm tired of pouring expensive race gas in cars and E85 hasn't really caught on in Texas. Maybe with Keystone getting shutdown it may be more attractive to vendors. Another reason for the setup with a cam swap I can change the dynamic compression ratio thus more power.

Interesting times we live in, I'm also in the electrical business but not ready to plug in my vehicles...

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[LT4USMC]

Originally Posted by PAUL K

A lot of good information in the posts above. Please let us know how the Hi-ports fit under the shaker scoop. Good luck with your build!

Thanks Paul, you have also help me thru the years bending your ear on the phone...

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