Plastic Fantastic 2

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Several of the Western road courses have db limits. We have one locally (Arizona Motorsports Park) that has a 96 db drive-by limit, and I can't pass it with anything I own. Some guys use Super Trapps and then turn the tip of the tail pipe 90 degrees away from the drive-by test stand. Doesn't help with side pipes.

I get it now...shit were I live there arent even any car shows not to mention no road courses.......there are coffee and cars type shows for guys with Mclarens, Ferraris, NSXs...etc. its almost the worst place ever for being a car guy.
 
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oh, and tested today.... 111db at 50' and 6000 rpm... I'd love ideas on how to quiet it without corking it (or losing the sidepipes).... my initial thought is Supertrap disks...

was that with the car moving or standing still?

what is it at idle up to say 2500 rpm? thats really when you will be going from standing still to moving, 111 db at 50 and 6000 rpm can only last for fraction of a second when its moving. what is the state regulations? and what is is inside the cabin at 6000 rpm?

my son took my 69 with side pipes to the ice cream shop parked out front got his ice cream, ate it then went back to the car and started it up and made the little kids cry, the dads were all laughing and he was apologizing....

Several of the Western road courses have db limits. We have one locally (Arizona Motorsports Park) that has a 96 db drive-by limit, and I can't pass it with anything I own. Some guys use Super Trapps and then turn the tip of the tail pipe 90 degrees away from the drive-by test stand. Doesn't help with side pipes.
this is why you're my hero.
 
I did spirals in my last C3, didn't get any significant reduction. The only thing that worked was quiet inserts - but those KILL power, I still have them around. I couldn't stand them so I went back to the other inserts - and then cut one apart to see why. It is NOT free flowing.... I'll dig it out for a picture...

as to the cone (vortex) and spirals.... this guy tested
[ame]https://www.youtube.com/watch?v=qmv2H9ulf3s[/ame]

the tl;dr is neither helped. there is a follow up video that I haven't yet watched where he makes his own mufflers..


and I'm operating on any track I want to run at limits to 105db (and my test was static so it would reduce a bit at 50 mph - which is the test speed)
 
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wax, so I can see the paint flaws better
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the new diff had a broken rear cover... so I bought a new one, this one comes with a cooler.... not sure I'll hook it up, but it was $45 delivered
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nice, do you have to pump the oil exchange or is some sort of siphon or gravity heat rise system? what is the third hole for temp sensor or vent?
 
new springs.... shorter
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so in news.edited Comp Cams card is for HOT lash... not cold lash... they must be trying to save ink....edited
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alright, think I'm ready for dyno tuning on Friday.
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and yes, I spent a lot of money solving a problem I didn't have..... ah well, the trolls get a laugh.

Most of us are just trying to improve our skills and learn from others. Too bad that there are critics out there discouraging people from sharing.

Looking good. Keep up the good work.
 
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screw the critics....I like what you are doing and its your car and your dime, so do what ever the eff you want.

what about the gas tank vent clamp? did that fix the leak?
 
the clamp fixed it

as for the trolls... I didn't know that Comp Cams defaulted to Hot with the solid roller cam. I could 'save face' and simply not say anything - but my purpose of blogging is to encourage others to share in my passion - even when I make a mistake (though I still wonder why Comp Cams didn't feel the need to add that one word - sure, it's obvious afterwards) build your car, it's not going to be perfect, even after you have lots of years of experience doing it. TV alleges that a car will run perfect after a week-long build. It doesn't, but it's okay, this is real world. stuff is going to happen, there's nothing to be ashamed of, and trolls are going to do what they do anyway... let them laugh, I have a sweet C3 they have their mommy's basement and an iPhone 4.

for those with FiTech... how to connect your laptop to your FiTech
[ame]https://www.youtube.com/watch?v=GgEtP6CYfIs[/ame]
 
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shorter front springs
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there, balanced
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old list
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new list this is for max points in engineering... I may even cave and put some kind of radio in it...edited
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since it was on the list, the ramps
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376 to the tire

for the record... we didn't mess with the timing.edited It has 18* initial then I think 20 mechanical... at this point it's not knocking and the motor is still 'new' .... safe tune get some more miles under it and maybe I'll revisit the timing.... I have my eye on the coil per cylinder conversion.....edited
 
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376 to the tire

for the record... we didn't mess with the timing.edited It has 18* initial then I think 20 mechanical... at this point it's not knocking and the motor is still 'new' .... safe tune get some more miles under it and maybe I'll revisit the timing.... I have my eye on the coil per cylinder conversion.....edited

thats pretty awesome especially if you havent dialed in the timing. i am sure there is some hidden power in optimizing the timing.
 
376 to the tire

for the record... we didn't mess with the timing.edited It has 18* initial then I think 20 mechanical... at this point it's not knocking and the motor is still 'new' .... safe tune get some more miles under it and maybe I'll revisit the timing.... I have my eye on the coil per cylinder conversion.....edited

thats pretty awesome especially if you havent dialed in the timing. i am sure there is some hidden power in optimizing the timing.

guess is at least 25 hp more. Since this 40% more then what I ran 2x before... thinking I need to get used to that.... and yet

humph.edited I went to PIR, they have noise limits.... 97 db noise limits. if you've been following along, you'll know that my noise at full song is 111 db.edited I didn't find out before I went but I'm so glad I did because I spent time with my parents - something that's been hard to do since I saw them a year ago....edited

but I have a problem to fix.edited Thinking a corkscrew with some steel wool as the first shot.edited I'm also not against injecting water to muffle the sound... I really need to be below 105 - from there it's arguable....edited
 
"Sounds Like" you need reverse Cut-Outs. So, cut outs are to open the system and get the HP - but yo have the opposite challenge. I did a quick dive. [seemed like a clever idea and wondered if anybody had done it before.]

Check out this video:
[ame]https://www.youtube.com/watch?v=QgA3mnpRUfE[/ame]

At about 2:10 he gets to the meat of the mod.

More weight, some complications, and if you went electric - could forget to switch and be Black Flagged - but an approach to consider. Any number of options in the aft (muffled) section to get to 97dB (or less). NOTE: when in OPEN - there is still flow through the aft section - you'll see that in the video when he fires it up.

Cheers - Jim

I don't know where in "class" your car fits - but the aft exhaust could blow a diffuser for some DF.
 
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I don't know where in "class" your car fits - but the aft exhaust could blow a diffuser for some DF.

The HP numbers* suggest I should change the entire system. The biggest issue with a cut out would be the individual runners don't meet a collector before they're outside the car. I'm pretty sure I don't have the time to fabricate an exhaust before the end of May; however, next winter I may fully refab this to put regular headers that go into side pipes ... for now, what you suggest may be the only solution... I'm also thinking a perforated corkscrew baffle with steel wool to absorb sound near the tip.

*the HP numbers, hopefully I'll get the sheets today, drops off at 6500 - otherwise it was well on its way to a lot more at the wheel. The motor basically starts making great power at 3500 then climbs a wall to 6500 where something else is happening.... need to analyze (valve control, spark control, fueling....)
 
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