[Jack Gifford]

Wow- I had no idea this was proceeding so well.
Please translate "hit the floor in six weeks" for this dummy...

[Skip Fix]

Congrats Lynn for a long project coming to an end! Looks good.

But we all know a 455 is all done by 5500 why are you pounding on your so much, I guess it's those huge 188cc ports

[Mo]

I assume by the pics and the fact that you mention push rod bulge that the intake ports have been moved?

Nice job. I'm sure we will be seeing more RA5 GTOs and T/As

[NHRASuperStock455SD]

Originally Posted by Mo

I assume by the pics and the fact that you mention push rod bulge that the intake ports have been moved?

Nice job. I'm sure we will be seeing more RA5 GTOs and T/As

Mo, thanks and thanks for picking up on that bulge concept. The RA-V's had very poor carb signal as they were very huge then necked down to the push rod area too quickly. It also is a very lazy port because it is way too big. We made the port smaller, but maintained the CSA around the pushrod by bulging around the pushrod tube. This keeps the port small just ahead of the pushrod area keeping velocity up and not create a brick wall with respect to velocity. We are hoping to make significantly improvement for 455 style engines and below.

Lynn

[Mo]

Originally Posted by NHRASuperStock455SD

Mo, thanks and thanks for picking up on that bulge concept. The RA-V's had very poor carb signal as they were very huge then necked down to the push rod area too quickly. It also is a very lazy port because it is way too big. We made the port smaller, but maintained the CSA around the pushrod by bulging around the pushrod tube. This keeps the port small just ahead of the pushrod area keeping velocity up and not create a brick wall with respect to velocity. We are hoping to make significantly improvement for 455 style engines and below.

Lynn

I thought this post addressed any driveability issues/concerns.

Looks like a win-win situation.

[Ron H]

Will you sell these complete bolt on or bare?

[NHRASuperStock455SD]

Originally Posted by Ron H

Will you sell these complete bolt on or bare?

We will sell them bare or complete to your specifications. However, I recommend light weight valves. As you all know RA-V's came with hollow stem valves for a reason. I have gone through the mill and back trying to maintain lightweight valve train technology. This is the reason we have only a 11/32 valve stem and 5.700 over all valve lengths. We are working on hollow stem valve pricing and titanium valve pricing.

Lynn

[Gach]

Originally Posted by tom s

FYI,cams are no problem,Comp and Bullet can make them.I just got one last week from comp.Tom

Tom, what did it cost you ?

[Gach]

I have gone through the mill and back trying to maintain lightweight valve train technology. This is the reason we have only a 11/32 valve stem and 5.700 over all valve lengths. We are working on hollow stem valve pricing and titanium valve pricing.

That is one of the smarts moves I've seen in after market head design. Lynn do you
have a ball park price for bare heads and intake, intake for Dominator ?

[tom s]

Lou,it was a little over $600 I believe for a one off custom billet.They grind them from a round billet.When a core gets made for more orders im sure they will be the same or close to std cams.Also I will be using 5/16 stems as that is what is in my street heads for the last 8 years or so.Std. early hemi valves were perfect on the intake side.Lynn,I have a set of shaft rockers now.Larry Long had them done for me so you might check who did them.I know Nunzi had them done by someone also.TomTom

[NHRASuperStock455SD]

Originally Posted by Gach

That is one of the smarts moves I've seen in after market head design. Lynn do you
have a ball park price for bare heads and intake, intake for Dominator ?

Thanks Gach, $2500 for bare head castings. The heads without water jackets will be about $500 more. It is usually $500-$700 for complete heads fully assembled, but not with special valves like a RA-V. Tunnel Ram intake will be under $1000 with the availability of either a 4 barrel or 2X4 barrel top and the ability to mill down plenum size. We will let you know what prices we get. I am trying to keep

After running SS and a Tunnel Port for lots of years and seeing them over hundreds of dyno pulls, valve train is the most misunderstood limitation on Pontiac motors. We got 7500 RPM out of my 455SD with 188 cc intake runners. A big part of that is valve train. We used to think the heads quit flowing at 6200. Not true, it was valve spring limitations due to valve bounce. My opinion we do it in this order:

1.) install lightest valve train weight possible
2.) use soft style seats as hardened seats exacerbates valve bounce as do stainless valves.
3.) run as much valve spring as you need to make power. Cheap valve springs on a Pontiac do not cut it.

Lynn

[NHRASuperStock455SD]

I am going to have someone do us billets. I will probably do a 50MM with an optional 55. We have both in stock blocks. 50MM is a roller bearing and 55 requires a slipper bearing.

Lynn

[azbirds]

How are you getting that bore size? 4.5 and 4.6 did you stretch the dimensions of the block?

[NHRASuperStock455SD]

Originally Posted by azbirds

How are you getting that bore size? 4.5 and 4.6 did you stretch the dimensions of the block?

We stretch, tease, manipulate, drill, miscombobulate, bend, cheat, argue, fight, insult, karaoke, drink, abuse, sodomize, politic, catywompus(ize), screw, debate.....master......masterbate, then go to sleep, wake up, pop 40mg of Prozac, then start over.

Lynn

[ponjohn]

I'm not familiar with the original design, are those chambers an updated design (like KRE D-ports and HP)?

[NHRASuperStock455SD]

Originally Posted by ponjohn

I'm not familiar with the original design, are those chambers an updated design (like KRE D-ports and HP)?

Here are the OEM head pictures with one comparing old and new.

[NHRASuperStock455SD]

I thought this might be helpful to post this email I received with the answers.

Mr. McCarty,
you are to be highly commended on your lasting dedication to see this project through, congratulations. the castings look absolutely outstanding, and i'm sure your well thought out changes of them will be rewarding. Thanks!

my questions are in regards to application. will they be able to mount factory accessories/brackets and be used in a street capacity? basically, if it fits under a stock hood, runs on pump gas, and is durable with moderate maintenance , it's streetable.

* Yes absolutely. We have made several steps to actually make this head more streetable than the original head.
o You can run the stock dual plane intake.
o intake port reduced for better volumetric efficiency.
o reconfigured push rod area to improve carb signal without losing power.
o around 75 cc combustion chamber as cast, but we are going to offer a larger and smaller combustion chamber by milling and machining.
o standard Pontiac style stud mounted rockers
o Stock block bolt on application
o All accessory bolt hole locations (same as Edelbrock).
o Stock appearance (especially with a can of spray paint).
o Offering port match to stock intake flange.
o improved water jacket cooling
o stock exhaust flange location
o reverse water flow will be future offering
o stock piston valve relieves (depending on cam and swapping hole for RA-V valve order)
o 2 inch to 2 1/4 headers in the works
o streetable single plane intake for single 4 or dual 4
o Intake with centrifugal blower/turbo capability


i am extremely excited at the possibility of having a "Ram Air V" powered car that i can drive and enjoy. thank you, for bringing this high quality head to market and i wish you great success with your endeavors.

Matt

thanks Matt

Lynn McCarty
CMI Motorsports
[email protected]
317-839-8378

[73LeMans]

I think the only better time to be a Pontiac fan may have been 1970. And thats only if i had 30k burning a hole in my pocket.

This is great news for the Pontiac crowd. Heck Im only 36 so I easily remember how difficult it was to get aftermarket Pontiac pieces. Im glad to say Im no tripping over the amount of vendors that devise and manufacture high quality true Pontiac pieces. Thanks!!!

[ponjohn]

Sorry Lynn.....meant comb chamber.

[NHRASuperStock455SD]

Originally Posted by ponjohn

Sorry Lynn.....meant comb chamber.

Oh, no problem,

This is the new style comb chamber heart shaped. It is simply killer in %CE.

Lynn