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@981KMAN Nicely done! Way to use your brain on this so the rest of us don’t have to. This forum is really something special. Thanks to everyone who contributes here and I honestly mean that.
So I tried the "Wire Full Open" and did not like the slight drone when cruising around town. So I wanted a way to have the exhaust valves close "part way" in the ~1800-3800 rpm range, giving the increased volume desired, yet not the full blast.... and some adjustability to select the desired exhaust level.
I found these split collars on Amazon for a 6mm shaft (that's what the Valve shaft measures), and black oxide finished for corrosion protection. They cost about $13 for a set of 4, so I ordered a set.
They took about 5 minutes each to install, mainly due to not lifting the car and working up close thus my eyes were taxed. They fit perfectly and allow for significant adjustability in how much valve closure you desire. When the valves pull shut, the split collar stop squarely on the valve mounting bracket.
I set them with approximately 70% valve closure, you will hear a very slight reduction in volume at ~1800 rpm when accelerating, yet you have to be listening for it to notice it, other wise the exhaust note sound smooth and very linear as the rpm increase. No drone, and a perfect increase in exhaust note volume in the 1800-3800 rpm cruising range!
Not so @unclemat .... since the McMaster-Carr Collars are also make in China, you are really slamming the use of Black Oxide Finished Steel versus Stainless Steel for this application.
When designing components, specifying the material & finish is just as important as the physical dimensions, next comes cost of manufactures (in reality - sometimes this comes first). In this application the Black Oxide Finish is superior to Stainless Steel or sufficient for its intended use, as listed below; (info from Materials Handbook & Cleveland Black Oxide):
.
Grip of the Collar on the Shaft - This is an essential performance aspect of the collar as it must not slip on the shaft. Black Oxide Finish has a superior surface grip that Stainless Steel. Black Oxide Collars are used for "shaft fixing and positioning" & "Linear motion stopper" (which is the application we are discussing). Stainless Steel has more surface lubricity and can more readily slip on their shafts.
Corrosion Protection – Black Oxide (also known as "Gun Bluing" or "Gun Blackening") can give corrosion resistance equivalent to 144 hours of salt spray exposure. Next time you are under your car, look around and see all the Black Oxide Finished parts. While Stainless Steel will provide better corrosion resistance, it is not needed in this application.
Cost: The Black Oxide Collars cost $3.50 each (including shipping), while the Stainless Steel Collars cost over $20 each (including shipping)(McMaster-Carr pricing).
In the end, either Collar (Black Oxide vs. SS) should work OK for this application...... yet if you want to pay $20 for each collar and get nothing better for the intended application go ahead. I'll keep my $$ for other mods to my Porsche.
Not so @unclemat .... since the McMaster-Carr Collars are also make in China, you are really slamming the use of Black Oxide Finished Steel versus Stainless Steel for this application.
When designing components, specifying the material & finish is just as important as the physical dimensions, next comes cost of manufactures (in reality - sometimes this comes first). In this application the Black Oxide Finish is superior to Stainless Steel or sufficient for its intended use, as listed below; (info from Materials Handbook & Cleveland Black Oxide):
.
Grip of the Collar on the Shaft - This is an essential performance aspect of the collar as it must not slip on the shaft. Black Oxide Finish has a superior surface grip that Stainless Steel. Black Oxide Collars are used for "shaft fixing and positioning" & "Linear motion stopper" (which is the application we are discussing). Stainless Steel has more surface lubricity and can more readily slip on their shafts.
Corrosion Protection – Black Oxide (also known as "Gun Bluing" or "Gun Blackening") can give corrosion resistance equivalent to 144 hours of salt spray exposure. Next time you are under your car, look around and see all the Black Oxide Finished parts. While Stainless Steel will provide better corrosion resistance, it is not needed in this application.
Cost: The Black Oxide Collars cost $3.50 each (including shipping), while the Stainless Steel Collars cost over $20 each (including shipping)(McMaster-Carr pricing).
In the end, either Collar (Black Oxide vs. SS) should work OK for this application...... yet if you want to pay $20 for each collar and get nothing better for the intended application go ahead. I'll keep my $$ for other mods to my Porsche.
My thought process is, at the price of the amazon ones, what would the risk be of trying them? If they break, there wouldn't be any damage to the car, correct? Just that the valve would be stuck closed or open. So periodically check there are no cracks in the collars and save some cash.
My thought process is, at the price of the amazon ones, what would the risk be of trying them? If they break, there wouldn't be any damage to the car, correct? Just that the valve would be stuck closed or open. So periodically check there are no cracks in the collars and save some cash.
edit: how many mm apart are the collars for 70%?
I am sure they will work fine and I would not expect them to break. The only risk would be removing the collars if the bolts corrode/seize. Extracting them/cutting them off would be a major pita in this location.
Of course the risk could be mitigated by applying anti-seize on the collar bolts.
Not so @unclemat .... since the McMaster-Carr Collars are also make in China, you are really slamming the use of Black Oxide Finished Steel versus Stainless Steel for this application.
My thought process is, at the price of the amazon ones, what would the risk be of trying them? If they break, there wouldn't be any damage to the car, correct? Just that the valve would be stuck closed or open. So periodically check there are no cracks in the collars and save some cash.
edit: how many mm apart are the collars for 70%?
I used 1 Collar per valve as shown in my picture. The Exhaust Valve Arm turns approximately 90 degrees in normal use. The amount that you hold the Valve open is based on your "tastes" and what sounds best to you. For me it was holding the Valve open 30% or about 27-30 degrees, Its all very subjective when you are on your back looking at the assembly. I first tried 50% Valve closure and while it sounded great, was a little too much exhaust noise for longer rides at 45 MPH. So I slid the collar towards the knuckle about 1/2 way again and that sounded best for me. Yet the best part of this solution is it's adjustability - you choose what sounds best for you!! Play around with it for a while, trying different positions..... You only need to let your exhaust cool down before adjusting or you will burn your fingers!
Plus you and unclemat are correct, there are many different material types and finishes for these Collars that will work just fine. I looked at the ones from McMaster-Carr, Grainger and Amazon, then chose the ones off Amazon as the Black Oxide finish is good enough for the application and as trial components, the cost was acceptable.
I ordered two of these, since the threaded Soul plungers are 5mm not 6mm like stock, and it was quite a bit cheaper for me to order from a CDN company.
is a high Tech Manufacturing enterprise that makes quality components, and the Collars I received reflect that. Plus these days.... "Made in the USA" does not always mean Quality. Depends on the manufacturer.
I ordered two of these, since the threaded Soul plungers are 5mm not 6mm like stock, and it was quite a bit cheaper for me to order from a CDN company.
@981KMAN I ordered 4 of the amazon ones you linked (one order). They will go in my garage until my GT4 arrives... Thanks for coming up with this great idea and also for giving me the directions on how to do it.
I am corrected. I wrongly believed that most of these components come from China these days. My error.
Made in the USA" does not always mean Quality. Depends on the manufacturer.
Astronaut John Glenn supposedly said: “My life depended on 150,000 pieces of equipment – each bought from the lowest bidder.”
Dave @ SOUL
__________________ SOUL PERFORMANCE PRODUCTS Quality Exhaust Solutions, Fair Pricing, and Outstanding Service
John Gaydos- Owner, Performance Specialist
Cell - (484) 883-6197 johng@soulpp.com
03-27-2022, 11:43 PM
