GoPro video, Mission Raceway

[lowell]

A lot of new changes from last year including bump steer and roll center, 255/40/17 star spec II's up front, recirc'd Tial MV-S so I don't have to let off going by the sound meter , added 3 degrees caster up front, rear wing, rear undertray, brake cooling deflectors, PFC01 pads, full floated Stoptech rotors, master cylinder brace...

All added up to a 4.5s improvement

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[V8srslow]

Nice 4.5 s is a lot in road race... Hard to push the 1gs but boost helps off the corners.

 

[cioc]

Rear wing and undertray...care to share? Also with the caster, did you use something off the shelf like the whiteline caster bushings or something custom?

 

[theamsoilguy]

Please share pics. Once my 944 project is done Im building up a 1g for road course.

 

[lowell]

Aluminum sheet, drilled to match the factory M6 bumper bolts. Aluminum angle on the muffler side and it joins up with the stock fuel tank shield.

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V1 caster: http://www.dsmtuners.com/forums/road-course-autocross/454870-1g-front-castor.html
V2 caster: http://www.dsmtuners.com/forums/road-course-autocross/313386-aftermarket-ball-joints-change-roll-center-7.html#post153225880

 

[cioc]

Very nice! Ballsy move on the control arms...having a rear arm fail on me last year I'm petrified of cutting and modding factory arms. Where does your undertray begin?...ever think of going the full length? I may attempt this next winter so I'm gathering ideas. Thanks for sharing!

 

[lowell]

What happened to your control arm? I've cut and welded sections into quite a few rear upper arms to correct camber and was never concerned about the weld joints.

The rear tray starts at the fuel tank shield. Up front I just have a panel between the bumper and front crossmember, but will be doing a full front underbody soon.

 

[cioc]

Too bad you're so far away or I'd say we should get our heads together and come up with something. I had a rear upper arm fail (Old Ingalls design) the day I switched to full slicks. Only got about 5 laps before one arm snapped and the other bent pretty severely. Fortunately there was runoff and I didn't lose the car however I did lose both rear JIC struts which were no longer available. Good reason to upgrade to the Ohlins. My front splitter extends all the way under the trans and connects via square aluminum channel that is bolted through both front north/south subframe braces. Working backwards from the aluminum channel...a full belly pan would be easy to install. Looking at Project White Snow's 200MPH aero mods, side skirts could be easily fabbed as verticle supports for the belly pan for easy removal. Combining all these ideas would make for one sweet undertray!

 

[theamsoilguy]

Your front tray is a lot how I didnt mind on my 944 track car and it worked well for me. I am also looking at lots of hood aero lately. I want all the air that comes in the brake ducts and rad to exit the top of the fenders and hood. I believe it will help with cooling to let the air escape better and with downforce by not letting that air under the car.

For my eagle talon chump car, I was planning on shortening the upper rear control arm for camber and just welding it back together, then a extra plate over that. My friend is reasearching the parts to fit a custom threaded piece in so that its adjustable, that wont work for the chump rules but my other Talon will get that design. If yours failed Im concerned, do you have any specs on the diamter and metal thickness of your part that failed?

Can I see your brake cooling deflectors? Home made or aftermarket? I found this car very difficult to route a cooling duct. I took mine off last race as they came loose and ended up with what I think was boiled fluid.

 

[cioc]

http://www.dsmtuners.com/forums/road-course-autocross/283880-brake-cooling-ducts-3.html

They work! Instead of using the Naca ducts in the bumper I am now feeding through a central duct in my splitter.

 

[eclipsegsx1736]

Nice! Any exterior pics of the car, wing, etc?

 

[theamsoilguy]

Ive seen the pics before of your mounting plate, thats given me a good idea and its better than what i did. I really didnt like that you had the hose under the brake lines. If you snag the hose and it tears out it could tear out the brake line. Im even pondering a naca duct on the top of the fender and goind down along the strut. ( wont matter to me what it looks like as my application isnt street driving ).

I cant wait to do all this to the second talon. My friend runs a boat manufacturing business and another friend of mine knows how to do carbon and fiberglass. I orderd a shitload of materials to make fenders, hoods, roof skins, etc that I will pick up later in the summer.

Let not hijack the post . Tell us more about the car. The rear undertray probably doesnt do much as is in my opinion. Pictures of your wing setup? If you have a rear undertray and wing, do you balance it out with a front air dam or splitter?

My track talon is still very heavy and very nose heavy. When I get some time I have some serious work to do on just weigh reduction, fixing brake cooling issues and then I also need wider tires than what I was running, more front camber, etc, etc.

 

[lowell]

Made these in about 10min the night before I went to the track.

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Wing is made from a gutted stock center section. I have pics of the whole build process that I'll post up, but basically only the top skin remains. I picked a NACA airfoil profile that closely matched and cut out a bunch of ribs. Added fiberglass cloth, end grain balsa, urethane foam and a spar. End result is 123lbs of downforce @ 175km/h, measured at the latch. That doesn't take into account lifting force on the hatch, as if you drive without the stock wing, the hatch will fly up.
The lower skin is one piece with the gurney flap and I extended the chord about 15mm to bring the upper and lower surfaces to a point.

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[theamsoilguy]

Very interesting that you have some data on the wing. Awesome. Cant tell much from the pic. My wing for the 944 and mounting braces arrived at my buddies shop from the USA. Cant wait to see it and mount it. I have been wondering how to measure the effects of the aero changes ( downforce only ). There are some options on that but I dont have anything yet.

Good job on the brake plates. I know the porsche has those available aftermarket in a few variations, Ive always gone with brake ducts myself. I might use how you did it for one of my cars that wont be allowed brake ducting as Im sure your approach helps.

You sir are ready for chump car racing. That series is all about fabbing up stuff yourself to keep the track costs down. My Talon ( 91 eclipse gsx actually ) is my chump car and I know I can easly drop another 100 hours into it to get it sorted out. I plan to race it at PIR one of the 24 hour races and I will be praying for rain when I do !

 

[arrowhead]

Glad to see more DSMs getting into road racing, very nice job on your car, very similar to what I am planning for undertrays,

Good idea on your wing set up need more wider angles of your pictures to get better idea where things begin and end, I have a wing from a GT3, the wide one, that I will try to use on mine .


Amsoil, remind your friends at the boat factory that these are racing parts, not for a boat, the tendency on the boat guys is to make them heavier than needed.

Keep us posted

 

[FIBA M - EC17PSE]

have you thought about any rear diffuser designs yet? i am looking to do what you done on the front but want to try do something other then flat on the rear!

 

[lowell]

Overall shot. This splitter is for street use only. 2" projection at the center, 4 3/4" off the ground.

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Modded stock wing element @ 13 deg AOA

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Lower skin and gurney are 1 piece.

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Wing profile is based off a NACA 6409 outline.

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[lowell]

Test fit of RPF1 18x10.5 +15, 275-35-18 888's. They stick out 2" all around, but my front and rear control arms are a little longer than stock.

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[theamsoilguy]

I run 275 on my track car ( porsche 944 ). They are big enough that generating enough heat takes a bit. Going 315 this year with the wide body kit. I cant imagine getting enough heat into a 275 for autocross.

But tell us more about your caster, bump steer and roll center.

My Talon I race in chump car isnt allowed camber plates and I need more camber up front ( only using the camber bolts ). So Im thinking of cutting up the shock tower to move the shock mount around to change that, which is allowed in the rules. I dont have the car lowered much as I dont want to blow out the stock shocks ( again the rules limit costs and Im stuck with stock shocks ). You seem to have modified the control arm ( hence the caster gain )

Chump is great because I spend way less than my other track car, but you have to get creative with making it faster as I cant buy go fast bits for it.

 

[TSiAWD666]

Why did you go to 10.5 wide wheels for a 275 wide tire? 9.5 would have been more than enough and saved you some weight plus unnecessary (and possibly dangerous) sidewall stretching. Just curious, not trying to be an ass What's done is done but I wondered if you had some reasoning behind it as you appear to be quite the form follows function type of guy (like myself).

I have 315 tires on the same rims coming next Tuesday, and am running 285/35/18 on the 9.5" version which fit about perfectly.

 

[cioc]

Holy tire batman!!! I agree with TSiAWD666 on the rim size selection for those tires, but that's the least of my concerns with this setup. The real concern I see is under full compression those tires are going to get eaten alive by your fenders and in short time that could spell disaster. This was the whole reason why I hacked my body up and put fenders flares on. Do yourself a favor and cycle the suspension without the springs to ensure you dont have rubbing issues.

 

[lowell]

Oh these aren't my wheels and tires, they're off the blue X in the 3rd pic. I'm deciding on what to buy so wanted to see how much fender work I'm in for with 10.5s. I have a couple of RPF1 18x10 +38's to try out, as well as some 18x10 +25s.

 

[lowell]

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