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Thanks Loren - looks great.

I hope to make more GGLC track days this year. http://gglotus.org/trkdays/ggtrkday.htm They are fantastic value (~$200 for 7 sessions). Plus being a Lotus event you both get to see other cool cars (Laguna had 3 Sevens, an original XI and an original 18 F-Jr among others) and you have plenty of people with tools and knowledge when stuff inevitably breaks

While it is a nice story and the guys did a great job, its not really true that they beat WRC cars. They were running in side event that happened to be running on the same course as Rally Mexico. And they finished 3rd in a class that had 9 entries (the other 8 were mexican) and of which only 6 actually finished the race. Also the car was running an E30 M3 motor which by itself is worth a lot more than $500 It was more like a older engine swapped 911 finishing in the midfield of a Porsche Supercup race during an F1 weekend. A good finish and a great story but definitely embellished to make it sound better that it is.

Congrats!

Absolutely - thanks for the reco

Official Laguna sound readings: Flat out acceleration past the sound station in 3rd gear at 8k rpm: 96dB vigorous acceleration in 4th ~6.5k rpm: 95 dB Coasting past sound station in 4th at ~5k rpm: 90.2 dB After talking to some people and listening to the car drive by(a friend did a couple of laps) I think that the current sound issues are more due to intake than the exhaust. I might have to create some sort of airbox to muffle the intake noise and maybe route some cooler air. Anyone done something in the past? Both me and the Caterham below kept getting called for sound so in the end we just kept coasting past 5 and then getting power through 6 and onwards. http://farm5.static.flickr.com/4045/4458996370_2870e23cf2.jpg Exhaust pics: http://farm5.static.flickr.com/4037/4458217645_ac71c10f15.jpg http://farm3.static.flickr.com/2708/4458998282_98b2936e08.jpg

There are no moving parts apart from the driver, the FIA had no choice but to allow it. The F1 press is saying that they may ban it for next year though.

Put the Hushpower on today and it is FANTASTIC!!!! Very quiet rumble at constant rpms with a nice growl under acceleration. The cool shell technology is great addition, I took a 15 minute drive and the muffler can was cool enough that you could touch it and count to 3 without burning your hand. The real test will be Laguna on tuesday - I think it might still be a touch too loud though it should be something a supertrap can easily fix.

Nice setup. Mine is a 20 inch long barrel with a 6 inch diameter and 2.5 inch inlet/outlet. It weighs just under 14 lbs which is about 5 pounds heavier than the original glasspack (8.5 lbs). Its at the shop right now and I should hopefully have it back tomorrow.

I ended up going with a custom hushpower muffler which arrived yesterday. If all goes well I should have it on and be back at Laguna for the GGLC track day on Tuesday. Will let you guys know how it goes.

from: [/url]http://gglotus.org/blog/?p=918 YouTube - MP4-12C: Jenson Button and Lewis Hamilton test McLaren's new car at Goodwood

I didnt know one of the makers of the Blastolene special also owned a Seven Any pics of your car?

Ask and you shall receive: http://gglotus.org/blog/?p=851

????? When did Brian stop making them?

Thanks for the input West Texas. I have been talking to Lee Thompson who was the contact mentioned in the other thread. The decision between the three (Hushpower, Phase 9, Burns stainless) is a pretty tough one to make. I like the coolshell part of the Hushpower. The Phase 9 may look awkward but the fact that the fabricator is local and has a proven track record with Formula Atlantics is hard to ignore. The fat that you use a Huspower and the fact that it is less than half the price of the other two options so I may actually end up going that way. Need to make my decision in the next day or two.

So it basically comes as a rectangular grometted sheet of metal with the heat shield material under it or do you have to make the cover yourself? Right now I'm leaning towards the phase 9/phase 10 solution but those will require an heat shield that I can cut and form to the appropriate shape

Lemons racing actually has an explicit rule against using muffler tubing for roll cages That's very cool - is there an airgap to the heat shield material and if so how much?

I actually did consider it - problem is that a passenger could easily burn themselves on the tip. I'm very interested in the Hushpower Cool Shell setup which claims to keep the can temp down to 200F. Lets see - as of now I'mm just collecting my options so that I can hopefully decide next week. I have a Lotus Club track day back at Laguna on Mar 23rd and I'd really like to take the Se7en.

Also spoke to Burns Stainless and they recommended going to a 2.5 inch (current setup is 3 inch) version of their 2 stage exhaust. http://www.burnsstainless.com/sm-250-450-17-2s.aspx 3 inch version @ http://www.burnsstainless.com/sm-300-625-17-2s.aspx they are also going to get back to me with a quote on a 24 inch long 2-stage version P.S. I'm posting all this info both as a reminder to myself and as an online diary of the various options so that the next person out there has some idea of what else is out there. Don't yell at me for over posting

Did anyone end up getting a Hushpower? I'm having sound issues in my ultralite (http://usa7s.com/vb/showthread.php?t=4728) and was wondering if anyone had gotten sound readings off th Hushpower units.

Keep the ideas coming. I just eyeballed the car and I dont think that there is enough room to go around to the back of the car. The rear wheels completely fill the wheel arches which mans going through the fender wont work. Also with the roughly 4 inches of ground clearance I cant go under the frame either. Will put out some measuring tape and look more carefully tonight. I just spoke to the guy at Quiet Horsepower (http://www.quiethorsepower.com) and he suggested either using 2 Phase 10 exhausts in series (pic 1) or a Phase 9 in concert with a phase 10 (pic 2). He builds exhausts for a lot of 911s and Formula Atlantic cars so he should be able to get it under sound but it sure will be an odd looking setup http://farm5.static.flickr.com/4021/4389805733_def52968a6.jpg http://www.quiethorsepower.com/images/side_914-6.jpg

Something like a second muffler in series on the side with the exhaust tube exiting out the back? Interesting idea - I'll have to see if there is enough clearance under the chassis to route an exhaust tube without impacting the suspension or the gas tank.

I was intentionally at max revs while passing the sound station. I've done the whole lift and change line at Laguna before and to me it just isnt worth it. Now that I have a good baseline I'm exploring options on how to reduce the sound level. I've started a new thread on the subject: http://usa7s.com/vb/showthread.php?p=39521 The Nittos are really good. Now that the release compounds are gone they are sticking very well and it actually takes some effort to get the wheels to break loose.

Couldn't you put the O2 sensors in the new exhaust? The U-bend solution could also work with an existing exhaust/heatshield as well. You can see the dual muffler Caterham I was talking about at http://gotbluemilk.com/web100215b/56/imagepages/image41.html Incidentally one of the previous owners of my car has actually taken it to Laguna and I even have a picture of it from a GGLC track day. Though I also have a picture of the Caterham above at the same event without its second muffler so maybe is was a higher sound day and/or the sound guy had the day off. http://farm1.static.flickr.com/35/103720832_cf11109f9b.jpg

I was at Laguna Seca for a sound check yesterday and got an incredible 109 dB reading. It was actually so loud that rather than the usual 3 lap sound check the flagger furiously waved me down before I could complete a full lap. Now the sound limit for Laguna is 92 dB (most other tracks are in the 102-103 range) and since that is my closest track I really would like to run there. I've spoken to the Hushpower folks about getting an exhaust to quieten it down but we dont really know if their solutions will actually do enough. One option would be to get their exhaust (~$200) and pre drill it for super traps. That way if I ever blow sound I can always put the traps in and hopefully pass sound. I also spoke to Phase 9 which is a local muffler fabricator used by a lot of Porsche guys and they suggested going for a 2 step solution. Use a single muffler for daily use that brings you down to the ~100 dB and then use a quick release second muffler on a u-bend pipe to quieten it down to the 92 dB limit. I actually saw a Caterham using this exact setup at Laguna and while its not elegant it does certainly work. What are other people using for mufflers on their Ultralites and are there any other options that I've missed? BTW I am running what I beleive is the stock muffler - pic below: http://farm3.static.flickr.com/2793/4313274614_e1f7dd2caa.jpg