[NHRASuperStock455SD]

Originally Posted by Tom Vaught

Typical Ford Intake, Mike. Did not take people long to figure out the very short center runners were not happy on the old Ford stuff. Having the runners on 2 levels is not an issue either.

Tom Vaught

Very true,

In fact when Bernie Knudsen threw the Tunnel Port project guys under the bus, the Pontiac Racing guys hired them! So we are just picking up from all that great work and millions of dollars the Ford Racing team did and never got to finish. From what I hear Ford was completely committed to the Tunnel Port design. However, Bernie was the GM of Chevrolet Motor division and hired by Ford and all the BBC engineering team was brought over, thus the splayed valve 429 engine was born.

On the longer runner intakes we extend the plenum front and back. Therefore looking on the outside, it looks like the runner are much longer, however the plenum extensions provide for a very close intake runner length and a bigger plenum. I will try to get a picture.

Lynn

[Region Warrior]

Originally Posted by NHRASuperStock455SD

Very true,

In fact when Bernie Knudsen threw the Tunnel Port project guys under the bus, the Pontiac Racing guys hired them! So we are just picking up from all that great work and millions of dollars the Ford Racing team did and never got to finish. From what I hear Ford was completely committed to the Tunnel Port design. However, Bernie was the GM of Chevrolet Motor division and hired by Ford and all the BBC engineering team was brought over, thus the splayed valve 429 engine was born.

On the longer runner intakes we extend the plenum front and back. Therefore looking on the outside, it looks like the runner are much longer, however the plenum extensions provide for a very close intake runner length and a bigger plenum. I will try to get a picture.

Lynn

Thanks Lynn and Tom.
Now i remember where i saw one.
It's on a local guys 8 sec Ford Ranger.

[cgeise]

I believe those are pictures of the Profiler intakes - the hitman on the right - the new Edelbrock for spread port Chev looks a lot like it - only shorter and seems to work very well

[BVR421]

Any chance these will work on a real Pontiac? ie: 4.120-4.25 bore?
or will the valves be a little too large

[NHRASuperStock455SD]

Originally Posted by BVR421

Any chance these will work on a real Pontiac? ie: 4.120-4.25 bore?
or will the valves be a little too large

They will work on a stock Pontiac block, my build up for dyno purposes is a stock 455 block 0.30 over, eagle crank and rods, stud mounted rockers, very typical street RA-V crate motor. Will give you updates as it goes together.

Just like the original RA-V it will work on a regular Pontiac OEM block with the obvious changes for a RA-V. Most people should be able to swap piston holes, and of course you always check valve clearance on any motor right?

Lynn

[Dragncar]

Whats the most reliable power Ford got out of a Tunnel Port engine? It seems like the bottom ends of the FEs were a problem.
A guy at our track just blew up a 427 side oiler with some factory looking aluminum heads heads. It ran 9.30s in a Mustang. He has a SOHC 427 also but it is just too valuable to race. There is a lot in common with the Pontiac and the FE, 4 head bolts and inline valves. But I think Pontiac has passed it up in reliable power.
I like any idea of finishing what Pontiac had going. All the new parts is just way cool.
You have to have some sort of love for the Pontiac engine to do what Lynn has done, thanks.
BTW, BBCs still idle like a can full of rocks.
Another guy at out track just blew up his 454. He has had 3 engines in the same time period I have had my 455 running the same low 11 times like me in the same car. Only I do it with pump gas and he race gas. Freaking unreliable Pontiacs, rod chuckers!!

[Tom Vaught]

Originally Posted by Dragncar

Whats the most reliable power Ford got out of a Tunnel Port engine? It seems like the bottom ends of the FEs were a problem.

SOHC Engines would make about 800 hp

Tunnel Ports were in the 720 hp range but detuned at LeMans for the 24 hr deal. Ford ran dyno tests at 7000 rpm for 48 hrs continous at about 600 hp level (less load on dyno) and did not have any failures. You could probably run at Tunnel Port at 650 HP for 24 hrs and have it live.

The guy who blew up a side-oiler engine did not know how to build a Ford Tunnel Port Engine.

Tom Vaught

[NHRASuperStock455SD]

Originally Posted by Tom Vaught

SOHC Engines would make about 800 hp

Tunnel Ports were in the 720 hp range but detuned at LeMans for the 24 hr deal. Ford ran dyno tests at 7000 rpm for 48 hrs continuous at about 600 hp level (less load on dyno) and did not have any failures. You could probably run at Tunnel Port at 650 HP for 24 hrs and have it live.

The guy who blew up a side-oiler engine did not know how to build a Ford Tunnel Port Engine.

Tom Vaught

Tom,

This must have been in the 60's? I know as early as 1978 we were getting 860HP, but that was much later. We also had sheet metal intakes, titanium 2.25 valves, twin dominators, in a drag race configuration.

What do you think with today's technology Ford would be getting out of those same castings? I know it is hard, but please speculate. I would say with the standard castings....that is, then with raised port configuration?

I know we have found just 20HP since then with oil chemistry and another 20HP with just fuel. Everything back then was too big and too heavy. I know this was NASCAR stuff, so I am not 100% familiar with the level of that early technology in NASCAR. I know Widmer came into the scene and changed a few things?

Lynn McCarty
[email protected]

[ponjohn]

Blacktopr mentions that the plug will be shrouded by the "bump" in the chamber.

How do you know if the cylinder head is going to fill CW or CCW?

John

[blaktopr]

Originally Posted by ponjohn

Blacktopr mentions that the plug will be shrouded by the "bump" in the chamber.

How do you know if the cylinder head is going to fill CW or CCW?

John

John, alot of it depends how the port is shaped. One person's "work" can be different from another. This includes how well the mixture exits the valve depending what is happening upstream. But the air/fuel exits "out" away from the valve. So if it was concentric (no swirl) it will still travel over that ridge. Port bias and valve shrouding lead to the direction you ask. With that, the direction goes from the intake side to the exhaust side, so it can be either direction. To have the charge go in the opposite direction would mean a stronger short side flow over the long side. Looking at newer chambers, you can see the valve/chamber configuration working toward a more even and contolled exit out of the valve. But remember, the charge will still travel away from the valve riding over the ridge. It follows the same situation as the bed of a truck. Throw a plastic bag in there, and go for a ride down the highway and watch what it does.
Here is a pic of a Pro Stock head's chamber done in flourecent dye. Look at the vortex behind the plug away from the valve. That is what happens when air/fuel passes over a ridge or obstruction. Then take a look at one of my vids.http://www.youtube.com/watch?v=MHO0CwIOceY
This is just a cast #62. But note the similarities.

[ponjohn]

Originally Posted by blaktopr

John, alot of it depends how the port is shaped. One person's "work" can be different from another. This includes how well the mixture exits the valve depending what is happening upstream. But the air/fuel exits "out" away from the valve. So if it was concentric (no swirl) it will still travel over that ridge. Port bias and valve shrouding lead to the direction you ask. With that, the direction goes from the intake side to the exhaust side, so it can be either direction. To have the charge go in the opposite direction would mean a stronger short side flow over the long side. Looking at newer chambers, you can see the valve/chamber configuration working toward a more even and contolled exit out of the valve. But remember, the charge will still travel away from the valve riding over the ridge. It follows the same situation as the bed of a truck. Throw a plastic bag in there, and go for a ride down the highway and watch what it does.
Here is a pic of a Pro Stock head's chamber done in flourecent dye. Look at the vortex behind the plug away from the valve. That is what happens when air/fuel passes over a ridge or obstruction. Then take a look at one of my vids.http://www.youtube.com/watch?v=MHO0CwIOceY
This is just a cast #62. But note the similarities.

WOW, the more I read and take interest in cylinder head design and velocity, the more I understand it is very very complicated. You don't just run a dremel down the cylinder and call it a day.


It also gives me a much better appreciation for making power. The r&d that it takes to make power in a "class"( whether pro-stock or stock eliminator) scenario is inconceivable.

[JLHarper]

Originally Posted by ponjohn

WOW, the more I read and take interest in cylinder head design and velocity, the more I understand it is very very complicated. You don't just run a dremel down the cylinder and call it a day.


It also gives me a much better appreciation for making power. The r&d that it takes to make power in a "class"( whether pro-stock or stock eliminator) scenario is inconceivable.

PONJOHN is right...its amazing and I wonder how far advanced we really are?

I know there are some smart, gifted racers/designers/engineers out there looking at this from a scientific approach.

What I am wondering is: how advanced or knowledgeable is the marketplace?

Are we really at the tip of the learning curve?

As much as the sport has learned with hands on experience...trial and error...mill and flow then race the heads/intake seeking more power and improvements... is there a significant area for improvements to be had if this was studied by say.... a group of physic professionals working with other engineers/scientists?

Since there are so many dynamics that happen from the intake to the head combustion and exhaust process, if it were attacked scientifically would there be some major breakthroughs? Or, are we already there and just fine tuning the science of intake/head flow?

Just wondering where you all think we really are with intake / head technology and how it fits with making power.

[blaktopr]

Originally Posted by JLHarper

PONJOHN is right...its amazing and I wonder how far advanced we really are?

I know there are some smart, gifted racers/designers/engineers out there looking at this from a scientific approach.

What I am wondering is: how advanced or knowledgeable is the marketplace?

Are we really at the tip of the learning curve?

As much as the sport has learned with hands on experience...trial and error...mill and flow then race the heads/intake seeking more power and improvements... is there a significant area for improvements to be had if this was studied by say.... a group of physic professionals working with other engineers/scientists?

Since there are so many dynamics that happen from the intake to the head combustion and exhaust process, if it were attacked scientifically would there be some major breakthroughs? Or, are we already there and just fine tuning the science of intake/head flow?

Just wondering where you all think we really are with intake / head technology and how it fits with making power.

FWIW, I feel we are still not even close (Pontiacs). Thats why you see some doing better than the masses with the same stuff. I basically had to forget what I used to do to heads once I looked at it more scientifically and using wetflow.

Lynn seems to have a handle on the head program. Same look with an updated design. No need to bring up the "old versions". This was redeveloped, not copied.

Here is something to make you guys think. You know and hear about turbulence or "backing up". Well check it out. Just remember the normal thinking of air getting drawn into a cylinder in a motor or bench. Watch and think how the pressures change during different phenomenom. I know a few might say What the .... during viewing. Can't see this on a dry bench. 98% of what people are using.
http://www.youtube.com/watch?v=KcSe_6iOoYk

[NHRASuperStock455SD]

Originally Posted by blaktopr

John, alot of it depends how the port is shaped. One person's "work" can be different from another. This includes how well the mixture exits the valve depending what is happening upstream.

blaktopr is correct here. Not only about swirl, but the non existence of swirl. What do you think a RA-V head has coming into the cylinder with a straight port? (Chew that one for awhile )

Recently we got a set of SD heads from a very good head porter. We had extremely good flow, but the CSA of the port was small. So, we sacrificed some flow in order to get that push rod area up to 2.7 square inches up from 2.35 square inches

This gave us peak RPM up to 7200 from 6700 and about 35HP average. What less flow and more HP? What a concept!

Many professional head porters go for shape first and flow second!

Lynn

[marks73ta]

Just a thought/question. I use the TRW SD455 forged single trough pistons. Would the head change to the RAV configuration require changing the pistons if I'm using the single trough valve relief? Or are the valve angles different enough to still require a piston change? Would be nice for me if they would then swap. Mark l

[Mo]

http://www.youtube.com/watch?v=DOdKlNDndOo

[71 T/A]

Any chance a low rise intake could be created to fit under the hood a 70s Firebird? Will headers and even exhaust manifold be created for the heads? How good will low end power be with these heads, which was a deficiency in the original Ram Air V heads?

[BruceWilkie]

Originally Posted by 71 T/A

Any chance a low rise intake could be created to fit under the hood a 70s Firebird? Will headers and even exhaust manifold be created for the heads? How good will low end power be with these heads, which was a deficiency in the original Ram Air V heads?

Sounds like you want the look. Low rise intake, exhaust manifolds? If that sorta stuff including low speed performance are concerns, this head and other high flowing heads are probably the wrong choice. You cant have a head intended to make big power at high rpm on smaller motors or big power on big cube engines and expect great low end too.

Always choose the head thats best suited for your application.

[BruceWilkie]

Originally Posted by BruceWilkie

Sounds like you want the look. Low rise intake, exhaust manifolds? If that sorta stuff including low speed performance are concerns, this head and other high flowing heads are probably the wrong choice. You cant have a head intended to make big power at high rpm on smaller motors or big power on big cube engines and expect great low end too.

Always choose the head thats best suited for your application.

I did not intend this to mean RA5 wont work at lower rpm. A head optimized for lower rpm range will work better at low rpm. A head intended for higher rpm power is better suited to do just that. If it happens to work acceptably at low speed thats fine. Some larger ports work acceptably that you would think otherwise.

To back what TomS is saying... One only needs to look at Fords 351c 2v head. The ports appear large but performance is zippy its generally a bigger port than a Pontiac d port for sure. The 4v versions were notably down in power at low speed. Same for std and CJ big block 429/460 fords factory iron(large and larger respectively) Part of the low speed loss was greatly attributable to cam specs! (and a choked factory ex port)

I agree cam profile can make a huge difference in how things behave.

FWIW I can drop a Pontiac 2.11 valve in the intake port of My Kaase heads with room to spare. It will still be driveable though. 413 cfm head flow, near .750 net lift cam with modest duration(288/298 adv 264/272 .050" .430 cam lift 1.83 effective rocker ratio) and modest overlap.(not a big cam duration for 528 cubes) My 528 is not yet complete but there are lower compression 521-557 ci versions with similar duration but shorter lift cams(Comp xr292 typical street grind) out there making 750 hp on the street and very driveable even with a victor and dominator and pump gas.(some on these boards would argue its not driveable) Pk power near 6500 expected. Im utilizing a tunnel ram and a pair of 750's and race gas or E85 due to my 13:1 compression. It will still be driveable and should still exceed 800 hp. Kaase says I'll have a fatter tq curve with the tunnel ram over the victor but smaller 750 carbs I'm using wont give significantly more hp over single domi victor combo. I could have opted for Edelbrock heads or Ford Racing SCJ with similar sized port slightly smaller bowls and valves. Id lose around 100 hp up top and gain very little above idle with the same cam.

The straighter the shot from the carb where the fuel is atomized to the center of the cylinder the less impact of supposedly lower velocity ports causing problems. There is more to velocity than meets the eye on a flowbench vs what is going on in the engine itself. Atmospheric pressure vs cylinder pressure, abrupt flow stops/starts from valve motion, reflected waves from those shocks, sonic wave reflections, carburetor air/fuel atomization, laminar vs turbulent flow, strength of exhust "slug" creating negative pressures behind it enhancing pressure differential as the intake opens at overlap, chamber purge of residual ex amount when the exhust closes at end of overlap. I hate to talk Ford on a Pontiac board but Kaase will tell you the flow number is merely the result of finding the best shape to meet the parameters. Much the same as my telling you folks you design a cam around an application not the LSA or .050 numbers.

The pics below are a Kasse p51 cylinder head 2.25/1.74 valve size. Top of the line in factory size/port location/bolt pattern Ford heads. (wimpy compared to pro stock pro mod heads available for the big ford.) These heads are intended for 429 thru @ 600 cid applications.

Valve im using for comparison is a 2.11" Pontiac.

I dont think Lynns revised RA5 head is too big unless your doing a Jim hand style tractor motor.

[Brian Baker]

NHRA Pro Stockers I think would be on the cutting edge of what JLHarper is talking about, and teams with big budgets have utilized wet flow research as well as Spintron research. With 500 max cubes available to them and a minimum weight requirement of 2350 lbs. the current E.T record of 6.528 and MPH record of 212.03 is a testament to the R&D that goes into making all of that naturally aspirated HP.