Scca Autocross And Weight Reduction

Hey all!
I wanted to write briefly about my most awesome first time experience with the SCCA and AutoCross on Sunday. I didn't know what to expect and I had a ton of butterfiles at the start of the day. The course was laid out beautifully and the car ran great. I should have a video up on youtube in a week or so for you to check out!

Due to my 01 GT having an engine swap my classing was in Sport Modified. This is a great class with very little limitation. Check out the lengthy PDF with descriptions of allowed modifications and the like.
http://www.scca.com/assets/2014 Solo Rules Book 7 w cover and links.pdf

Part of the allowed modifications in this class is weight reduction, including the removal of the rear seats. The total for a SM RWD 4 seat coupe is 1800 lbs plus 200 lbs per liter. My minimum weight in this class with the driver is 2880 lbs. 1800+(5.4 x 200) At a stock curb weight of 3305, the old girl has a bit of a diet to go on to loose the extra 500-600 lbs depending on what I eat for breakfast.

SOOOOO....Saturday as I was cleaning out the car, I noticed my carpets needed a good scrubbing. I removed the front seats and went to work. I will say my next mod will be putting race seats in place of the factory units. The drivers power seat felt like it weighed at least 75 lbs!

Then I remembered that I could remove the rear seat. 7-10mm bolts, a couple clips and the rear seat and rear seat head rest was out. Then I decided to remove the spare tire, jack, tire iron and why stop there? So, I removed the trunk carpet and all the trunk panels. Really starting to look like a spec racer!

I pulled out my digital scale and began weighing all the parts I had removed. All total, I reduced my total weight by 91 pounds! I still have the factory seats to replace and can remove interior trim panels, stereo, speakers and carpet. I could also replace the hood and body panels with carbon fiber if I want to get really crazy!

400-500 more lbs before I get in trouble with class regulations, I just don't know that there is that much to be lost! (FYI: I know someone will respond with out reading through 300 pages of SCCA Rules, the K Member can be replaced, but must be an equal/greater weight as compared to the factory unit!)

I just signed up for an SCCA membership for next year and will be out at least once a month to have fun and work on my driving! I'm hooked!

bhuff30 said:

The unfortunate part of all that weight loss: it came off the rear tires. You may find the car to be a bit more tail happy next season.
Getting weight off the nose can be more challenging. I didn't look through all the rules... but here are a few ideas: battery relocation (to trunk), tubular A arms, coil overs, remove evap canister, PS delete (probably a bad idea at auto-x), abs delete, heater delete, ac delete and sound deadner.

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Thanks for the tips Brian. I have already relocated the battery to the trunk, so I am good there! I like the suspension suggestions, however coil overs I don't think I will be doing any time soon. I like my ride height and my skills are not up to par to be changing suspension geometry for each race. This is also my daily driver and I enjoy the comforts of things like AC, Heater and power steering. You are allowed to add 50lbs of ballast to the car, so if the rear breaks loose too much, I may consider that. I would also like to put an IRS under it which will add a bit of weight in the rear.

Thanks Again!

Uploaded a video to YouTube of a lap at the autocross! Check it out! View: https://www.youtube.com/watch?v=4mij-NbU0e4

rconaway said:

Changing to coil-overs doesn't mean messing with the camber every race. You will be shocked to see how much of a difference they make in cornering . If you change the K-member also, you can cut a lot of weight off the front end, minimize the dive, and stop the front end from pushing.

I rebuilt the engine and used the aluminator block to take another 100 lbs off.

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I wouldn't HAVE to change the camber before every race, but many do. I would be interested to see if coil-overs really made a noticeable enough difference in lap times to justify the cost.

Many SCCA classes don't allow you to run a K member. The rules for Street Modified state "Alternate subframes are allowed to facilitate engine mounting only. Suspension pick-up points on the subframe must retain standard geometry. Weight of the subframe must be equal or greater than the standard unit."

The only way I could drop weight with the engine block is by running the Ford GT aluminum block. Ford Racing used to sell this block, but has discontinued production it appears.

Thanks for the advice!