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View Full Version : Some Interesting 2013 GTM Race Stuff



crash
11-11-2013, 01:54 PM
There is some good press stuff here...

http://paddocktalk.com/news/html/story-238265.html

crash
11-11-2013, 02:01 PM
I know I haven't talked about the GTMR in quite a while, but that is because I was so busy helping out with the FFR PDG GTM and running www.myraceshop.com that I haven't had a lot of time to dedicate to the never ending bodywork modifications. Well, I have managed to get a few things done recently and here's a couple pictures. Coincidentally, I started down the path of the hood vents long before I had ever seen the 818, but they do end up resembling them in both placement and design. I guess we were just thinking alike!

2329123292232932329423295

Sorry for the crappy cell phone photos.

David Hodgkins
11-11-2013, 02:06 PM
Crash, I've been waiting for updates on this build! Can you tell us more? what other mods did you do? is the roofline taller? It kind of looks like it in one of the pics...

:)

crash
11-11-2013, 02:20 PM
David, the roof line is, in fact, higher than the original FFR GTM. I have tons of pics and video that I will release at a later date when I have time to edit and put the videos together, but since Richard started talking about the inspiration for what he has done on the FFR PDG GTM, I thought I should at least give a reference to what he was talking about. I don't think they will be the same(I haven't actually seen what he did on the FFR PDG GTM as of yet) but thought I would just share some pics since the front of the GTMR was referenced by Richard. :) (In another thread)

I have been working on lots of really cool stuff, but most of it is on the FFR PDG GTM. We should be running a FLIR rear camera this year that "sees in the dark" so we are not so unsure about who or what vehicle is coming up on us from behind. Not that that happens a lot, but the problem is that on the rare occasion that a faster car happens to catch us as we are passing slower cars, we are temporarily blinded by the lights from the cars we have just passed and unless a spotter is telling us that there is a faster car coming up it can be dangerous. So this system, which works on heat alone, will allow us to see the cars behind us and whether a car is closing or falling back without any concern for being blinded by headlights.

http://www.flirmedia.com/MMC/CVS/Automotive/AM_0001_EN.pdf

We will still be running the regular rear view mirrors as well.

crash
11-11-2013, 02:45 PM
Just a quick run down of what happened there.

The windshield has been relocated further forward and higher than on the original FFR GTM. As such the nose needed significant alterations.

First step was to fill in the original vent locations with foam and then cover with a layer of resin and glass.

I did the same with the "bubble" area by the windshield as well.

Then the area was covered in body filler and sanded until the original vents and bubble, basically, didn't exist.

As you can see, I needed to shorten up the nose quite a bit, so I cut a two inch section of the area by the windshield out and set it aside.

Then I went about shortening the nose to see how it would look and how everything would fit. A lot of this stuff really has to be done in your head. You have to visualize the finished product using some temporary lay ups and then work towards the goal. Sometimes it comes out as envisioned, and sometimes, most of the time, one has to adapt and adjust on the fly.

Next was to layout some alternate designs on the nose to see where all the stuff would fit and how it would look. I tend to "modify as I go" and this was no different. I keep trying things, shaping, then standing back and seeing what I like and what I don't like. My primary focus is good functional design, but aesthetics are following very closely behind in second priority.

Because there is a step under the nose that has to be there for the front bulkhead that supports the windshield and closes off the drivers compartment, yet I didn't like the original windshield to nose interface, there were some difficult areas that needed to be addressed. This was made more difficult because the higher windshield means that the area that the original FFR GTM has under the nose where the front bulkhead is is basically non-existent. So the increase in interface angle along with a "step" that is built into the exhaust vent areas is the result.

Anyway, so after that little hurdle, I glassed back in the 2 inch windshield interface section and then got busy on the step and shaping of the vents.

Metal forms with release agents were used to keep things symmetrical and level.

Basically what you see in these 5 pictures took me MONTHS worth of work.

I am not happy with the windshield interface line to the windshield, and, actually have already altered it so that it matches up better with the front of the noses lines and the upper windshield line. This is purely aesthetics, but, like I said, looks are also very important to me. I, no doubt, will keep adjusting, and this may not even be the finished design that I go with. I am considering two others. Along those lines, I would love to hear what others think about the nose so far?

BTW- At last count I am on gallon number 21 of body filler.

JCHRacer
11-12-2013, 10:47 AM
Looks great Crash. Was there any science involved in choosing the new location for the vents. Depending upon the shape, some cars have a high static pressure zone at the base of the windshield which would make it poor choice for the exit air for the nose heat exchangers. Did you guys get some pressure data from testing that indicated a low static pressure zone?


I know I haven't talked about the GTMR in quite a while, but that is because I was so busy helping out with the FFR PDG GTM and running www.myraceshop.com that I haven't had a lot of time to dedicate to the never ending bodywork modifications. Well, I have managed to get a few things done recently and here's a couple pictures. Coincidentally, I started down the path of the hood vents long before I had ever seen the 818, but they do end up resembling them in both placement and design. I guess we were just thinking alike!

2329123292232932329423295

Sorry for the crappy cell phone photos.

crash
11-13-2013, 01:08 PM
There is a general train of thought that the vents should be at the apex of the arch, whether that be wheel well/fender, or some other body part. In this case because the windshield is moved forward, the peak of the fender arch is much closer to the bottom of the windshield. As the fender arch now coincides with the nose arch and the windshield is much closer to that location a balance was met by moving the vent about 6"to 7" from the bottom of the windshield and still kept it as close to the apex of the arch as possible. Then there was the area consideration for the size of the vents. It came out pretty close to convention as far as inlet and outlet ratios.

fastthings
11-14-2013, 05:16 PM
Cool, looks good Crash

crash
11-18-2013, 02:53 PM
If I can get it to post, here is a 3/4 view that really shows how much shorter the nose is...

23456

Roger Reid
11-18-2013, 08:13 PM
Crash, What size tires are you planning on fitting under those fenders?

LCD Gauges
11-19-2013, 02:34 AM
Interesting hood design, I'm sure that will improve the downforce quite a bit! Are you making a smaller air inlet on the nose, or will those 'caps' be removed
to install some sort of air ducting?

crash
11-19-2013, 11:44 AM
Nose opening will be the same as what I ran on an 800 HP Trans Am car. As I am aiming for significant amounts of HP the exhaust vents will help things significantly as far as air flow is concerned.(As opposed to the TA car that had no hood vents.) I have my numbers as far as area required for the radiator inlet, and am trying to lock down what I am doing for brake cooling. Talking with a carbon ceramic brake company and they say that the amount of cooling required is much less than on a steel rotor. I will probably go with a steel rotor cooling setup and then tape up if the ceramics don't need the extra cooling. It is easier to do that than to cut into the finished body.

IIRC, tire sizes are 365 rears and 305 fronts. Just like the brake cooling, I can always go smaller and be okay, but it is hard to stuff a bigger tire into a fender that it just won't fit under. You know...like the old saying about 10 lbs of poo in a 5 lbs bag?:)

crash
12-04-2013, 05:38 PM
It's go time! :)

kabacj
12-04-2013, 08:30 PM
Good luck Crash.

Be sure to let us know if you guys stream any info from the 25.

John

Fraser D
12-04-2013, 09:13 PM
Have fun guys!
Will you be running a video link this year?

crash
12-09-2013, 11:44 AM
Just an update...we got our ***** wooped this year. Qualified 15th, moved up to 10th in 3 laps with Davy Jones at the wheel and then experienced an engine fire. Bad fitting on fuel rail. Driver alright, but car severely damaged from firewall back. Suspension and transaxle were OK, but engine, wiring and some fuel lines were toast. We cut it all out, put in the spares, and got the car running. Ran the last hour of the race so that we finished the event, but the car was not happy, and neither were any of the drivers or crew. Tremendous effort by all on the team, but obviously not the result we were looking for.

Just a word to the wise...DO NOT use the adaptor fittings to attach the -6 fuel lines, our any fuel line, to the LS3 fuel rails. They have plastic parts in them, and the design is not sufficient to handle increased fuel pressures over stock settings. I can not stress this enough. IF YOU HAVE ONE OF THESE ON YOUR CAR, I WOULD HIGHLY RECOMMEND THAT YOU REMOVE IT. I have simply welded a stainless steel -6 flare fitting to the rail inlet on other projects, and someone told us that there is now an off the shelf version that has this feature from Summit/Jegs/Etc.

LCD Gauges
12-09-2013, 12:15 PM
Good to see you all got back on the horse, and finished through adversity.

When you refer to adapter fittings, do you mean these? How much pressure was used on your system? What is different from the OEM design that would make
these aftermarket fittings fail? Thank you for the heads-up!

2410124102

kabacj
12-09-2013, 02:52 PM
Oh man , that just sucks.

I was watching live timing and scoring and I could not imagine what could have broken that would cause you guys to be out for so long. I did not even consider a fire. Yeah nothing worse then a fire to cause wholesale damage.

A good fire system is on my to do list for the winter. Did you guys learn anything about what works for fire supression in the GTM?

Thanks
John

crash
12-09-2013, 04:02 PM
I was one of the people on the radio and I was instructing him to pull the actuator on the lower right panel. We had also gone over the location of the fire actuator in "pre flight" briefings both times Davy has driven the car with us, but he did not pull the actuator. I don't know why.

Honestly with all the crap that the lawyers have made us put on this car it dramatically slows down how fast we can get out of the car. The added items and procedures may help in particular circumstances, but there are really only a couple things I worry about when driving a race car, and fire is absolutely positively number one on that list, and by a large margin. I have suggested that the same setup that is used in the Grand Am DP cars be used in our car going forward. That would be an automatic system for the engine compartment, and a driver actuated one for the drivers area.

crash
12-09-2013, 04:03 PM
2410124102

Yes, that looks just like the adaptor we had, but ours was black anodized.

kabacj
12-10-2013, 05:50 AM
I have suggested that the same setup that is used in the Grand Am DP cars be used in our car going forward. That would be an automatic system for the engine compartment, and a driver actuated one for the drivers area.

Many thanks for the good advice.

John