[johnta1]

Try a texture like shark skin on the tube.

[dci]

Originally Posted by johnta1

Try a texture like shark skin on the tube.

LOL, I already do that !!!!

John I used your calculator for port csa for a set of my RA5 heads I'm porting for a guy and after doing the port it looks really big. It's a 541, 4.375" bore, 4.5" stroke, 8500 rpm deal. I came up with a 4.5" csa at the push rod tube tapering down to the bowl 3.31" 92 percent of the valve. The opening at the tube is 2.50" x .980" on both sides of the tube minus the radius in the corners. I haven't flowed the head yet, but I'm a little concerned. I guess I'm just used to looking at E-heads and this looks big. I suppose because it is basically 2 E- head ports in one RA5 intake port LOL. I have to admit though I thought my RA5 intake port opening in the plenum was to big (2.650"), but that's definitely not the case. At least not on my 455 I built. That thing rips through the r's. What's your thoughts?

[dci]

Here are a couple of pic's of my DCI RA5 intake port after opening it up to the 4.5" CSA. I also took a couple of pic's with a DCI Tiger Head intake spacer over the RA5 port for comparison. I guess I'm so used to looking at factory D-port heads and E-heads. That I'm just taken back by what other brand x engines are using for port size. This definitely is an eye opener!!!!!

[dci]

Here are a couple of pic's with the DCI Tiger intake spacer over the factory RA5 head and Lynn's head. Talk about contrast.

[RAMAIR RICK]

Don, thanks for posting these photos, they speak VOLUMES as to what your DCI designed intake port can become if ported. I know personally that my set of DCI Ram Air V heads being ported by Jim Robertson have even a larger cross section that the pushrod tube tight point. We have a .625 dia. tube to allow for a 7/16" pushrod. But mine engine is a mild Pump Gas Woodward cruise EFI engine, so I am sure true racers will and can go even larger as the the architecture of the cylinder head will allow it for the high end and high rpm races. All of the valve train is in line, which becomes an important factor, as some guys will go into the 8,000 to 10,000 rpm range to maximize their HP Goals!!!

[dci]

Thanks Rick. You and Mr Robertson need to let us all see what you have been up to. Start a thread with your build and pic's so we can all see and enjoy. If you guy's don't mind sharing flow numbers and port speed. That would be nice too.

[dci]

Rick we are waiting :::::::::::

[dci]

I didn't mean to scare everyone off. I know we are chartering unknown territory here, but we can still speculate. It is really exciting to me to finally have a cylinder head platform that we can easily reach the CSA's that other brands have been at for awhile now. We need to start thinking outside of our traditional small port, low rpm box that we have been trapped in for so long. Look at what the front runners that have done that are doing with the Tiger heads. Not so long ago it would have been unheard of to even think about spinning a traditional Pontiac to 7,000 rpm and now guy's are reaching 9,000 plus. Exciting things are happening for Pontiac enthusiast that are willing to let go of our past. Think Big, Dream Big !!!!!!

[Tom Vaught]

I am old enough to remember when the well prepared "Oval Port" Big Block Chebby heads would stomp a Rectangular Port head consistently at the track.

Same deal with a Ford Tunnel Port head vs a good High Riser/Med Riser Ford head with the 427 engines.

When the Ford guys stroked the Ford 427 engine with 1/2" stroker crank: 3.76" stroke (stock) vs 4.25" stroker cranks the engines came alive with the larger port heads.

Tom V.

[dci]

Tom, It is amazing how far we have come through the years. The Chevy square ports and Ford Cleveland 4 barrel ports were just to lazy for heavy street cars and tight converters, but at the track they performed very well with taller gears and looser converters. My heads have the best of both worlds though. I cast the heads with small enough ports and with plenty of air speed for street use, but there is plenty of real-estate to open them up for high rpm track use too. As a matter of fact my ports in as cast form are even a little to fast and need opened up a little for anything bigger than a 428. Those older cylinder heads from back in the day were made with big lazy ports. Back then we didn't understand that we needed velocity to keep the fuel suspended.

[Tom Vaught]

Originally Posted by dci

Tom, It is amazing how far we have come through the years. The Chevy square ports and Ford Cleveland 4 barrel ports were just to lazy for heavy street cars and tight converters, but at the track they performed very well with taller gears and looser converters. My heads have the best of both worlds though. I cast the heads with small enough ports and with plenty of air speed for street use, but there is plenty of real-estate to open them up for high rpm track use too. As a matter of fact my ports in as cast form are even a little to fast and need opened up a little for anything bigger than a 428. Those older cylinder heads from back in the day were made with big lazy ports. Back then we didn't understand that we needed velocity to keep the fuel suspended.

X2

Tom V.

[Ron H]

Taking PMD PontiacMastersDrivision to a new level!! Thanks for all your effort and to Pontiac enthusiasts who know what they have and keep em keeping on.

[RAMAIR RICK]

Ron H, speaking about taking our hobby to new level. I find the hardest thing for me was, 3 years ago was to let go of MY MINDSET, I had a 455ci with 9.25 compression and 1972 455HO heads on it ported in the 240-250 range at 28". it made 540hp at 5800rpm. NOW compare that MINDSET to what GM has be offerings for 5 to 10 yrs, with LS engines sizes 376ci to 427ci and heads that flow AS CAST, in the 350-370CFM range, and the RedLine at approx. 7,000 RPM. The Difference was as Tom and Don has stated so well, The CSA is the king along with a good valve size and air speed to feed that given valve.

Now LET'S take GM's modern approach. WHAT if I just put a set of Pontiac heads that had the correct CSA and valve size and CFM flow of an LS head, in the 350-370CFM RANGE. WHAT would my little 455ci at that TIME, made HP wise and REDLINE WISE, and TORQUE WISE???? My little combo would have BEEN in the 600-650hp range, and pulled in the 6400-6800 REDline Range. FUNNY because of the Cubic Inch Size it STLL would have been a milder engine then the OEM GM LS 427 Z06. So I had an education that made me realize that engine does not know it is an OLD DESIGN PONTIAC, it JUST wants to BREATH like ALL the MODERN ENGINES out THERE. We as Pontiac enthusiasts, now have MANY Cylinder HEADs that are out there for us to build our DREAM engine with MORE Power then the OEM limited LS platform. So if I got a real EDUCATION about what the engine REALLY needs even if is a PUMP GAS Street/Strip combo, so can the REST of the PONTIAC COMMUNITY. THEN if we WANT to look like a SLOW 14 second Cruising MUSCLE CAR, GTO or FIREBIRD or Grand Prix, etc. But run deep in the 11's and maybe even high 10's, we CAN and have the biggest %&* eating GRIN on our FACES as we blow past one of the latest Camaro, Mustang, and HELL CAT.

[RAMAIR RICK]

After my personal awaiting/growth about what I believed what Pontiac engines should and could make horsepower and torque wise, I sold that very engine to a very good friend of mine from Carb. to oil pan to headers. I have now ventured out and I am currently building a Pump Gas Poncho all Alum. 550ci. and with Don Johnston's DCI Ram Air V heads on it along with EFI and (2) 4500 series Accufab throttle bodies. It should be a fun Woodward Cruiser and occasionally racing it. I personally am very happy with my mindset growth, as well as building a Ram Air V engine MY WAY.........

[Darren 639]

Wow Rick I am building currently the same exact engine I even have two Accu fab throttle bodies also fuel injection, five heads 565 in.³ with Don currently also. I cannot wait to get this thing done to and after reading your last post about the cylinder heads you got me even more excited can't wait. Poor Don going to get a lot of phone calls from us asking him questions now I feel really bad for him

[dci]

Darren, Don't feel bad for me LOL. I know how to ignore the phone when I'm busy, but please don't think that I'm not working on your project when I do. Just keep in mind there are only two of us here and there are only so many hours in a day. I have been at this now for 35 years and it's always the same story. I feel like a broken record telling everyone. I'm working on it. Since your a business owner you will understand this statement. I don't make money keeping your project here. I make my money when you pick it up. Or in your case, when I ship it. So believe me, I want the customer to have their engine more than they want it. Thanks for understanding though !!!!!


Rick, You can probably expound on the time table involved in projects of this magnitude. Unfortunately for the spectator it's like watching paint dry LOL. In my world though, I'm going 100 MPH in the slow lane. I wish I could go as fast as everyone thinks. If I could I would be rich !!!!!


Ironically you two guy's are building similar comb's. Rick is getting a little more carried away though than you are Darren. He wants a 850-900 HP street beast on pump gas. I don't think that's what you are after ? If it is we need to step up the porting program a little LOL.

[RAMAIR RICK]

Darren 639, I am putting my little Pump Gas Poncho combo into my 1968 GTO, 4 spd car. So on the outside it will look very stock, even with Custom made Pontiac Rally II rims, and plans to have Redlines on the tires, for the look. So for me my GTO will, with me in it be about 3850lbs, plus or minus 25lbs. I am very much looking forward to cruising with it up and down the famous Woodward Ave., here in Michigan, on Pump Gas with alittle over 11:0 to 1 compression and EFI and FULL exhaust. Yet at the Pontiac Nationals I am planning on running in the 9's and front wheels in the air!!! What type of car are you planning on putting your Pump Gas Poncho engine into? Also we are stroking a new SCAT Forged 4.5" stroke, to be 4.595" stroke, to ensure we don't have any piston issues that some people have with the 4.75" stroke cranks. Also planning on Hyd. Roller Lifters for now, we shall see as the build progresses. Funny thing is Darren, AS MY EDUCATION and my MIND grew, so did the Engine and what I wanted to be and do for me. The education has taken me about 2 plus years to get me where I am, and also the intake port Square inches has also increased as of a result, about 3 times. Jim Robertson has the Ports just where we want it for my planned dual purpose stock looking 1968 GTO Muscle Car. Darren if you would like to share with us what your plans are with your combination, I am sure, many more individuals will come up with their own combinations with some BAD AZZ DCI Ram Air V heads>>>>

[Darren 639]

Hey Rick I had a 68 Gto with 722s aluminum rods Doug Nash crash box car was stock appearing ran 140mph back in 1990s when 140 was fast. Miss that car. Now I have a long rod 535 , tubbed stick 62 tempest went 160. The project I am doing now is a 63 lemans it will look all stock no roll bar. Stock interior dog dish hub caps on bias ply tires. Hopefully it will resemble a super duty clone. I can't wait to get it running but I'm still in middle of body work. I'm going with two accurate throttle body's solid roller,fast fuel injection, 4.75 stroke moldex aluminum block,g force 5r. I cut the wheel tubs and added in 2 inches l but put the stock wells back in. Have you built your headers yet that's the thing that's holding me up on my body I don't know if I should run the full front fender wells or do I need to make room for the headers I need to borrow a cylinder head eventually so I could get to that. I don't know what size header to run maybe you could let me know what size you are running. thinking of step....

[RAMAIR RICK]

Darren, it sounds like you had and have some very cool cars!! That is cool that your 1968 GTO was that fast back then, I am shooting for 138 to 145mph in the 1/4 with my GTO. Funny I just had Liberty Transmission, here in Michigan, take my Chrysler Hemi 4 spd and Faceplate 2,3,& 4th gears for me along with all of there Cryo. and metal treatments to the transmission components. What size was your engine in the GTO? and what kind of et's did you get back in the 90's? Darren much like you, I like the stock or understated look at least on the OUTSIDE. My Best friend Mike McCarty has a very cool 1963 Lemans, here on the PY boards. He won best engineered car at Norwalk last year, it is a VERY Cool car, they are classic, in their looks. I am sure yours will be a WICKED stock looking with a LARGE RAM AIR V ALIVE under the HOOD!!! AWESOME!!

[RAMAIR RICK]

Darren, to your question about headers, I am planning on step headers, and so far we came up with Stainless Steel, 3 step headers, 2'', 2-1/8" and 2-1/4", into a merge collector and a 3.5" exit size, to my Dr. Gas Crossover exhaust. Yes I found a local guy that I will have to bring my car to him to build them. I do know that Don Johnston has contacted Mark at MADDOG headers to make DCI Ram Air V headers for some Pontiac vehicles. Maybe Call Mark up and see if he also offers headers for your 1963 Lemans.