First I would like to congratulate all those that endured the 7-10 days, raced and survived the runoffs, not an easy task. Congrats to John Black, Bobbie Sak and TJ - it was a great race and I enjoyed watching. John was one lucky driver at the start, with nowhere to go, getting the squeeze play. Thanks to the SCCA live broadcast we could enjoy the great competition from the comfort of our homes. Hope everybody involved in the OTE's were ok. Frankly our cars are safer than my house- tore my hamstring stretching while watching- must have gotten a little excited.

Sorry to hear about Cliff- he drove a great race but as the saying goes, rules are rules. Thanks to the improvements in SRF/SRF3 compliance we have the most competitive and fair class in SCCA.

I have intel of what cost Cliff the win. As suspected it was the muffler. The rule states that the holes on the inner tube have to communicate with the space between the inner and outer walls. Whether you fill that space is up to you as long as you pass the sound test but the fenestrated inner wall must communicate with the space between the inner and outer wall. Cliffs did not and that is a power advantage, plane and simple. Game over. There is a difference between a tightly packed muffler using a fibrous material and an extremely fine mesh metal material wrapped numerous times around the fenestrations essentially closing the holes. The opinion of the compliance officers was unanimous and the appeal was not accepted.

This type of infraction, one that is a performance advantage, will always be upheld if found in tech.

Expect a more defined description of what you can and cannot do with your exhaust system to be published prior to the 2017 season. I look forward to a new format for the Runoffs in 2017- so that more of us can attend.

I am about to install a Gen3 kit and would like to do it right and in a way that is unquestionably legal. I don't recall anything in the instructions about muffler packing. Is it required? If so, what material is supposed to be used and how should it be installed. Thanks as always for the help.

I don't know what the definition of communication is from a racing standpoint but if it holds pressure it is not communication, if it leaks pressure no matter how little from inner core to outer housing it's communication. How do we define communication? Now if rules had said you had to use a specified material that's another thing.

Does Enterprise have a specific part number for the material to be used as muffler filler?

Gents I think Cliff may post on this at some point (no guarantees) and if so, that may shed some light on the subject.
Clearly it's a topic we all need clarification on.

Expect a very detailed description of what communication is and what is legal in relation to the muffler. This will be in the rule book and be well defined.

for now if you have wrapped that inner fenestrated core- it's probably not legal.

The CSR's are selling muffler packing material- it is fiberglass in a bag (I have one to put in).

Was it wrapped with steel wool? That would still let combustion into outer chamber. I was told if you can put a pick into holes and no restrictions to pick thru hole it is ok. The muffler comes with steel wool in it from enterprise and it goes around tube. It must of been wrapped with something metal or something hard enough where the pick did not go thru holes in tube. At that time the muffler came apart to see what it was covering holes.

As you all know I was disqualified from the 2016 SRF3 race. Unfortunately, I believe that our GCR, Installation Manual, & Tech Process have failed miserably however I will give you my insights and let you make up your own mind. I want to first describe the tech process, then I will talk about the method of muffler packing we used, and why it is a crock of shit that we were disqualified. Please watch the attached video, as the tech stewards assumed that the steel wool sleeve was a barrier that increases airflow, and it is the opposite, the steel wool flows more air than a densely packed fiber. Had tech unpacked the muffler and objectively evaluated the parts, we believe the decision would have been different.

TECH PROCESS

The first step in the Tech process was to remove the end cap of the muffler and attempt to use a 90° pick to puncture the packing material through the holes in the muffler tube. However, our muffler is packed with a combination of a stainless steel wool and mesh tube that slides around the muffler tube, and fibrous packing material. Tech was unable to puncture the wire mesh with the 90° pick.
However, this does not mean that the surface is solid, or is decreasing the airflow through the holes as compared to a muffler packed entirely with fibrous packing materials; it just indicates that the steel is stronger and less flexible than the fibrous material.

After our muffler failed this test, the muffler was taken to be evaluated by multiple tech stewards and the chief steward. At about 6:00pm I was notified by the Chief of Tech that I was disqualified per section 9.1.8.E.2.J (which coincidentally isn’t a real GCR section) but implies that I modified the muffler, but can only be referring to the muffler requirement of:

Exhaust may be plated or coated. Repairs may not alter the configuration or tuned length of the header or tail pipe. Standard Muffler Kit G1190523 (including Standard Muffler P/N 390523) is required for all events. For tracks with stricter sound requirements Quiet Muffler Kit P.N G1190524 is available as a replacement for that event.

As the Class Compliance Chief, any decision that Mike makes is unprotestable, however since this decision was made by the Chief of Tech, we had the right to protest the decision, and then appeal the SOM’s decision. Just like any typical weekend the protest must be filed within 30 minutes of the receipt of the Chiefs action. In our protest of the Steward action, we identified that the packing materials were available off the shelf, the muffler had not been modified in any way, nor had the functionality of the muffler been modified. We requested that the SOM disassemble the muffler, and view the packing materials separate from the muffler and they did not. I attempted to provide background on muffler packing from bristolcore’s owner who has been packing mufflers & selling muffler packing materials for 30 years, and the SOM did not accept the 3rd party information. I also asked the SOM with what frequency the Tech stewards open mufflers and evaluate the contents for compliance purposes. When I posed this question, I was told

“they do it regularly”.

However, in my further review of the GCR, there is not a single glass in Club Racing competition, that has a muffler rule, including FE that specifies how a muffler must be packed, or that defines the contents of the muffler. The closest two rules are SM that requires a muffler meet a dimensional requirement, and FM that requires the use of supertrapp baffles. At approximately 8:45 pm on Sunday, after the entire paddock was clear, I received notice from the SOM decided that our packing method was a “modification” to the muffler. When I received this decision, I asked the SOM if they had disassembled the muffler, they said “no, we compared your muffler to a new muffler provided by enterprises” (if youre interested in these GCR references they are in the below link for the google drive)

Unlike a typical major, the next step the Court of Appeals at the runoffs must be completed within 1 hour of the receipt of the SOM’s action. If you have been through the court of appeals, you are aware that you must provide “new” information to the court. With the guidance of a drivers liaison we discussed that the GCR that since the SOM viewed repacking as a “repair” and that repacking is addressed in the Technical Bullitan 006-2016 however this technical bullitan is not in the GCR, nor is it currently available on SCCA-E.com that there is an Error & Omission from the GCR that allows packing of mufflers with “any acceptable packing material” including Stainless Steel Wool, and Fiberous Packing Materials.

Again, in the Court of Appeals, I attempted to provide the specification sheets, and packing process, and background information for “standard muffler packing” however the COA did not accept this information. I also requested that the COA remove the packing materials and evaluate the materials separate from the muffler, as they were to determine, if the muffler was modified, and if there was a missing rule from the GCR. They said to me that the pictures that they had of the new muffler and my muffler were enough and they would concede that the muffler could be disassembled. I noted to the Court of Appeals that if it was true that we had modified the functionality of the muffler, which the result of that modification would be, increased straightaway trap speeds and increased sound readings. I requested that they evaluate those two items, and no review was completed.

From my perspective, the only objective evaluation of our muffler packing was an attempt to poke a hole in the packing material, and as we know, air is smaller than a pick. At No point in the 2016 Runoffs post race tech, was our muffler unpacked, and the stainless steel wool evaluated for airflow or “communication” as bruce calls it. All technical personnel involved assumed that this piece modified the muffler and restricted air flow through the muffler core, and subsequently increased power & increased sound. As you can see below there is not any significant evidence of additional “power”


During the 2016 tech process our post race muffler was compared to a “new” from enterprises muffler. (I only observed this muffler from the photos that the SOM & Court of Appeals used to compare to photos of my post race muffler.) From these cell phone pictures it appeared as though the muffler came with a fiber packing material in a sheet style. This is important because our GCR Rule regarding the muffler is woefully inadequate and does not address servicing or repacking of the muffler:

This one sentence requiring the use of the muffler is the only information that the Chief of Tech has to base his opinion of legality:
Exhaust may be plated or coated. Repairs may not alter the configuration or tuned length of the header or tail pipe. Standard Muffler Kit G1190523 (including Standard Muffler P/N 390523) is required for all events. For tracks with stricter sound requirements Quiet Muffler Kit P.N G1190524 is available as a replacement for that event.

As a result, the Tech Stewards, determined that re-packing or servicing the muffler is considered a repair and must be done exactly as it is delivered by Enterprises. However, we have received 2 muffler assembles with our G3 conversion kits (for dad’s car in 2014 and Cliff’s car in the fall 2015) and purchased a 3rd muffler because one muffler fell off the car during a 2015 race weekend. Each muffler was received from Enterprises with different packing material as follows:

1. Without any packing material,
2. Loose Fiber packing material and some wire mesh (presumably steel wool)
3. FiberMatt like packing material

So the Tech Stewards comparing one new muffler, to our repacked muffler is flawed from the beginning.

Why and How did we end up packing the muffler this way?

With the common knowledge that the density of muffler packing improves exhaust flow and has some positive impact on engine torque, throughout 2015 & 2016 we were constantly repacking the muffler with fiberglass. Some fiberglass lasted only 1 on track session, and generally none lasted more than 1 weekend. Frustrated with the waste associated with frequent repacking the muffler, we began to look for alternative packing material.

Early in 2016, I spoke with Mike Davies about muffler packing. Mike informed Cliff that muffler packing material of any standard type was acceptable(steel wool, loose fiber, fiber pillow) i.e. much like oil in an engine.

With the above insight my dad began researching muffler packing materials. I eventually contacted Bristol Core, 5310 N. Street 6B, Canandaiqua, NY, http://www.BristolCore.com, 585-919-0302. I worked directly with Morgan Curtice, Owner. Bristol Core manufactures and sells muffler packing materials. They supply Yamaha motorcycle race teams. Morgan provided me with a detailed description of the product he was recommending and believed that it would lengthen the life of our muffler packing materials by 5 to 10 times the current life we were experiencing.

Wade,
The method of packing absorptive (perforated core) engine mufflers with continuous yarn fibers such as fiberglass E-glass or basalt, with or without a layer of steel wool immediately around the perforated core, has been common practice since the early 1990's for motorcycle, ATV exhaust systems. In face, Owens Corning introduced continuous glass fibers into mufflers in the mid eighties with Saab and Volvo OEM (See history of OC's Silentex product). We currently supply many high performance exhaust manufacturers with our yarns and steel wools for the assembly of their production mufflers. Mainstream and well known manufacturers such as FMF Racing, Yoshimura, Supertrapp, Vance & Hines have been utilizing these materials along with the same installation process you used for 10-15 years. The materials I sold to you, (HD Steel Wool Sheet and Spec 19) are available for sale to the public and reproduction materials (i.e. not works or prototype materials). Please let me know if you have any further questions about the history, availability or common use of the materials I provided you with.

When it comes to installing the loose packing, my recommendation is to:
1. Start with the empty muffler secured in a vice or clamp with one end-cap removed (the core and other end-cap should be in place)
2. A small plastic bag can be placed over the end of the core to prevent yarn from catching on the perf core or steel wool. A wrap of masking tape over this rough edge will work as well.
3. Use small handfuls of the yarn, tamping it down around the core in a spiral fashion with a blunt tool such as a piece of doweling
4. Distribute and compress the yarn as uniformly as possible
5. When all of the yarn is in the muffler, it’s ok to force the packing in an inch or so in order to maneuver the end-cap into place. The packing will rebound and fill that void.
Morgan Curtice - Owner
Bristol Core Inc.
http://www.bristolcore.com/Default.asp
5310 North Street 6B
Canandaigua, NY 14424

Nice, this covers all of the bases, common packing practices, acceptable materials, and then Dad decided to confirm with Mike D the legality of the product combination but we are racers, racers experiment, racers look for advantages and we push the envelope and yet we want to evaluate the legality confidentially because we value racing in a spec class and we do not ever want to be accused of being cheaters we run all of our “gray area” ideas by Mike Davies.

Dad asked the following three questions of Mike Davies:
1. Whether muffler packing was open, so long as standard muffler packing material was used.
2. Secondly, I asked if any type of fiberglass packing material was acceptable.
3. Third, I asked if use of steel wool was an acceptable muffler packing material.

Mike agreed all of these above statements were correct and during the conversation, I informed Mike of our intended muffler packing. Dad explained a steel wool sleeve would be fabricated from steel wool wire mesh with an ID the size of the OD of the inside muffler pipe and the sleeve would be the full length of the inside muffler pipe (muffler end plate to end plate), the steelwool sleeve would be welded to itself at the end to keep it from unraveling, and the remainder of the packing would be a loose fill fiberglass muffler material. Mike and I agreed the materials were acceptable but Mike was unsure that the packing method and sleeve would be acceptable.

As an aside:
1. We engine dyno tested an unpacked muffler and a fully packed muffler, you can see the dyno results on torque in the attached google drive.
2. We used this muffler packing for the first time at runoffs testing. It was run for 14 test sessions, each 25 minutes in length. The muffler was opened and inspected after the test sessions and we found no deterioration of the packing material. We used the same muffler packing for the 4 days of qualifications. We then changed to an identically packed muffler for the race.
3. The muffler that ran from testing is the muffler that is disassembled in the video.


Enterprises has failed to provide sufficient guidance to the competitor & technical staff to evaluate the legality of any serviceability or muffler packing as indicated by the items below:
1) GCR SRF3 - regarding muffler:

Exhaust may be plated or coated. Repairs may not alter the configuration or tuned length of the header or tail pipe. Standard Muffler Kit G1190523 (including Standard Muffler P/N 390523) is required for all events. For tracks with stricter sound requirements Quiet Muffler Kit P.N G1190524 is available as a replacement for that event.

2) GCR PG 168 - Appendix F. Technical Glossary

Muffler – A component, whose function is to reduce the sound level from an exhaust system.

3) Gen3 Installation Manual - regarding muffler:
Install the header using the supplied gasket (gasket comes on the motor under the protective plate) between the head and the header flange. Tighten the nuts to 30 ft-lb. Use the 1.9 rubber hanger and stud on the frame just as before. d. It’s suggested to safety wire the springs to the header to prevent them from coming loose. (similar to a 2-cycle kart header) Vibration will cause these to pop off. a. When using the muffler (Part # G390523), replace the stinger outlet pipe with the header adapter, muffler, and stinger. Replace springs and tighten band clamps. See figure 38
4) Gen3 Installation Manual – Reccomended Spare Parts: (Muffler Packing Material Not Included)

Description Part Number QTY needed
Alternator belt G991411 1
Oil filter / Motorcraft FL910S G301022 1
Ignition relay WM901006 1
Fuel pump relay WM901006 1
O2 sensor G990504 1
Starter G992701 1
Oil PSI sending unit G980495 1
Fuel PSI sending unit G980495 1
Air filter WM301020 1
Spark Plugs G301041 (6510) 4
Thermostat G300999 1
Oil filter adaptor O-ring 392499 1

5) SCCA Enterprises Technical Bulletin 006-2015: (is no longer posted on SCCA-E.com) and could not be provided to the Runoffs Technical Stewards by SCCA Enterprises for evaluation.

We have received concerns centered around Muffler to Tail pipe fitment.
After testing a batch of Prototype mufflers (10), fitment and the security of the slip joint seemed to be acceptable.
Our header vendor is producing the “Spec Muffler” for us. It’s just what we need, no more, no less. The Muffler reduces the sound level 2 to 3 db, is re-packable all without consuming engine output.

However customers installing Mufflers from batch 1 or 2 have voiced a concern with the slip joint being too tight or to loose.

In either case, here are some suggestions to help with installation of the mandatory “Spec Muffler” update.

First of all, Follow the instructions. When cutting the tail pipe to install the muffler, the total length of the tail pipe should not be changed. Keep with-in +/- .375” This is a GCR rule. Instructions are posted and available on our web site under
“Spec Racer Ford Tech Doc’s” http://scca-e.com/srf-gen3-muffler-inst ... -addendum/

too tight or too loose…

On the tight side, you could use a sand paper drum to smooth the ID surface of the slip joint area of the muffler. If the tail pipe was coated previously, be sure and carefully remove all of the coating from the slip area of the 2 tail pipe pieces. Some of the fitment problems seem to come from the normal variance of the muffler tubing OD, usually around +/- .020”. We and our vendor have no control over that variance.

On the looser side,

We changed the number of slits cut into the slip joint area of the muffler. It is acceptable to have up to “4 slit’s” cut in the slip area. That will ease a tight fit and let it clamp more securely on a looser fitting combination of parts. This can be done with a1/16” thick cut off wheel and a die grinder.

We chose to use a band type clamp, they offer the most service flexibility. They do not dent the slip area of the muffler or tail pipe pieces. I think some people are being a little too cautious tightening the clamp.…I tested some clamps to failure from our current batch of a couple hundred.

SAE Torque for a .250” steel grade 5 to 6 fastener dry is around 8 to 10 Ft Lbs. I placed a clamp on a 30 MM deep socket. Held the socket in a vise, torqued the T bolt in steps and noted the results. Each sample clamp failed in the same way.

Short summary:
8 to 10 Ft lb all is well
12 to 14 Ft lb all is well
16 to 18 Ft lb starting to deform or bend the “T Bracket” where the band wraps around it and
starting to bend the .250” X 28 T bolt
20 to 29 Ft lb continues to deform or bend the “T Bracket” and bend .250” X 28 T bolt
30 to 31 Ft lb the Band fails where it raps around the “T Bracket” part of the clamp.

Be sure and get the clamp tight on first install and retighten after the
first couple of track sessions. If you are unsure how tight to tighten the nut on the T
bolt…aim for 11 to 12 ft lbs …use a torque wrench to get a feel for it.

If you still have an issue with the slip joints, you can use any style commercially
available 1.750” exhaust tube clamp. “Caution” the thinner the clamp, the more it dents the muffler and tail pipe slip area and make it very difficult to service.

As an option, you could use an approved clamp and orientate the muffler body in the
vertical position, use 2 small tack welds on the inlet end of the muffler. (non-serviceable
end closest to the header collector) I would never tack weld the outlet tail pipe piece to
the serviceable end of the muffler.

Repacking serviceability

The serviceability or removing the aluminum end cap from the Muffler has been difficult for some. A revision has been made to how the muffler is assembled . The revised Muffler end cap Part # G390525 availability TBD. Can be installed on the earlier mufflers. No change in performance between the end cap designs, strictly for ease of serviceability.

I have also heard reports of the screws that hold the end cap to the body loosing up. It’s a good idea to check those during the first couple of track sessions as well. After everything has been heat cycled several times and they are tight, they should be fine.


Last, if you continue to have problems with the muffler update. Please document with pictures and send all data to Mdavies@scca.com

The Tech stewards are required to use the language in the GCR and considered the repacking of the muffler to be a “repair” and implied that the muffler must be packed in exactly the same way as the sample muffler provided to the Technical Stewards, which as noted above only resembled one of our three purchased mufflers.

In my review of the remainder of the GCR, there is no class that has a packed muffler that is to be evaluated by Tech Stewards, which calls into question the Tech Stewards ability to evaluate the difference between “standard packing materials” and assist Enterprises in defining the difference between “muffler packing” and “modifications to the muffler”. During the protest and appeal process we requested multiple times that the muffler be disassembled and the packing material removed to demonstrate that it was not a modification to the muffler and this was not done by Tech, SOM, or the Court of Appeals.

SCCA Enterprises must clarify the muffler packing issue. If the muffler is to be packed it is our experience that the combination of the steelwool & fiber dramatically extends the life of the muffler packing materials, and reduces the overall cost and time of the muffler.
Additionally, this experience has convinced me that Enterprises needs a formal and confidential process for compliance related questions so that no staff person or competitor will need to suffer an event like this again.

Manufacturer of Packing Materials: http://www.bristolcore.com
Spec Sheets for packing materials, packing process, speed trap information & unpacking video dyno results:
https://drive.google.com/open?id=0ByQzo ... E9sdHBrRXM
Unpacking Video
https://youtu.be/r_aAjt40mKk

Cliff,

Congrats on winning the race on track. Sorry to see you getting hosed by a bunch of nonsense.

Regards,

Peter

Great post Cliff
You drove a,great race
Can't imagine how disappointing this must be
Thanks for the transparency