Larry Meaux Interview - Port Texturing!

[Autoholic]

I found an old interview from 2012 with Larry Meaux, the guy behind PipeMax. One of the questions was about port texturing and he has seen it add 15-25 FWHP. Apparently he does this a lot with the heads and intakes he works on now days. I wonder if just media blasting the areas that would benefit from this, would be the way to go? A heavy media to give it a sand casting texture. The idea behind texturing the walls of ports and intake runners is that the rough surface causes small vortices which help float the air fuel mixture a long. This helps the fuel stay suspended in the air, using the boundary layer. For engineering types, this is very interesting as it muddles the issue on pipe wall surface roughness. Typically the smoothest pipe will flow the best, having the smallest head loss due to the pipes. Engines are just complex air pumps. However it is easy to look to the best known example of surface texture to improve performance - golf balls.

http://hotrodenginetech.com/pipemax-creator-larry-meaux-on-race-engine-head-porting/

[Yellow Truck]

Thanks for posting that. I like the fact that he did an A-B-A test and got the same result on both tests.

[Autoholic]

I thought that was cool as well. He gave a lot of examples of the port texturing working. I'd take his word for it, he has nothing to gain or lose by stating the facts about doing that to an engine. It's probably one of very few tricks that can gain you roughly 20 hp.

[jayb]

I wouldn't say he has nothing to gain, he offers that as a porting service.

I really like his Pipemax program, but it is also not completely accurate.  Gotta take all that kind of stuff with a grain of salt...

[FErocious]

   Port texturing and boundary layer conditioning has been around for a while. The concept has a lot of merit, but to adopt this method is to ascertain the current dynamic performance of the port in question. A full port velocity profile mapping , comprehensive flowbench pressure differential testing methodology based upon the engine's airflow demand vs effective port area at all lift points, and as a bonus, a wet-flow analysis will help to evaluate the port condition. There are also areas in every intake port that require a varying degree of excitation of the boundary layer to effectively reactivate that particular area. Certain areas throughout the port may have air/fuel separation pockets that are problematic. A discontinuity at the right spot will reintroduce the wet fallout into the air-stream and serve to recondition the mixture.
   This texturing can also be used , to good effect , to provide the "illusion" that a too-large port is in fact "near the correct size " by increasing the working boundary layer thickness. I also see all to often that people smooth-out a perfectly good CNC resolution discontinuity in ports and combustion chambers. In my mind, this should be left in place, unless it is determined that the port needs to be fixed to meet the demands of the application.
   It is abundantly clear in my mind that Larry Meaux really knows his stuff. His understanding of the workings of the high rpm IC engine is pretty much second to none and I am not alone in that affirmation.
   

[fekbmax]

Port texturing as well as combustion chamber dimples both are very interesting . I'd think though that it wouldn't be something that a back yard engine builder or even many good engine shops should do and then expect the same kinds of notable gains as the guys that have the knowledge, equipment and resources and the R&D to do it properly. . Port texturing maybe not so critical but as things are now it's still something I think would be best left to the pro's. Now a days we know that just one miss cut or one wrong move can make a lot of difference in a ports flow.  It seems as if there are several articles where the combustion chamber dimples need to be placed in specific patterns depending on the combustion chamber design. . It seems to me that if it was something that made such substantial gains, then it would be done more regularly by the great head porters. .

Dam, it's hard to stay away from this sight. Great people, tremendous knowledge, good advice and most of all many different opinions which is something I like.

[Joe-JDC]

Not to disagree with some of the things he said, but this is not new, and as Jay said, "take it with a grain of salt".  I was taught by a master porter back in the '80s who did work for major automotive racing team, and we found that tricks to make a port work were the result of poor shaping in some part of the port.  Anytime you have to "crutch" something to get it to work, there was a problem leading up to that point.  I have done back to back dyno testing of different textures and dimples, also, and did not find those kind of horsepower improvements from the texturing.  It all comes back to how well the porting was accomplished in the first place, and how much time was spent on finishing the ports for optimum flow.  Many porters use the "roughing" technique because they don't want to spend the time to make their work look professional.  Just my opinion, but I have worked with one of  the best, and I feel I have a little experience in this matter after 43 years, too.  Joe-JDC. 

[machoneman]

Yes, various forms of textured surfaces, dimpling and the like have been around for some time. Yet, as mentioned above, even high end builders would have a tough time experimenting with these techniques after a port was rendered near perfect for a specific application. Without some very sophisticated equipment, the home builder, average pro builder, etc. would be hard pressed to 'prove' the concept unless they have the time and $ to do A-B-A testing. I'll guess that high buck teams (think: F-1, NASCAR, Pro Stock) do in fact such experimentation as they have the equipment, bucks and motivation to get very last hp regardless of the cost. JMO! 

[Autoholic]

Joe, I'd like to pick your brain on surface finish. The engineer in me sees the best possible flow coming from the smoothest surfaces. However when you put a little bit of moisture into the airflow, some turbulence is helpful in keeping that moisture suspended in the airflow. Dimpling the walls is just one way of trying to accomplish that. Theoretically, I think an entire port sanded to a rather rough finish (40 or 60 grit) would help do the same thing. The boundary layer would be thicker at the walls than the boundary layer of a completely smooth surface. Is this beneficial or would it only hurt performance for reasons I'm not seeing? I know that at really coarse grit levels you would need to be quick about it or you'll remove too much.

[Joe-JDC]

On dry intake ports that use EFI, a smooth finish with generous radii, will flow best(SVO Contours used extrude honed TB, intake, heads).  On a carbureted engine, or TBI, a rough texture helps keep the fuel in suspension, and not wash down/cling to the sides of the ports.  I always try to finish an intake port with at least 60 grit textured cartridge rolls or flapper grit paper.  Shoot for a 60 RMI on the finish.  I polish the exhausts with 180-220 grit, and flap them with 180 grit as a final to clean up any textured marks left over from the polishing.  On today's Nascar engines and many road race engines that use the D-3 style Yates/Motorsports heads, the intakes are finished with a finer 80-100 grit cartridge roll and flap to get rid of the CNC marks and finalize flow.  You can't go wrong with texturing the intake ports, but to intentionally use a mangled carbide burr is not necessary.  I sometimes will sandblast the intake ports after porting is completed and then pressure wash them before final machine work is completed.  I like to sandblast intake manifolds and leave them with the rough texture, also.  Of course, pressure washing and pre-wash before install is a must on all intakes that have been ported and shipped.  Joe-JDC

[Qikbbstang]

The more advanced the porting the more I question the significance is there a need to somehow synthesize interaction of adjacent and opposing cylinders all sequentially mixed up and pulling from eight cylinders in a V-configuration from the plenum?....
    I've read how pulses from the header primary tubes can reach all the way back into the chamber and beyond the intake valve.