cobramatt
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Posts posted by cobramatt
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on the 3rd pic on what looks like is the z is a gurney flap of some sort on the vertical part of the wing? I have not seen that before. why? I probably screwed up the names but it has been a long day.
jimbo
That is a good observation Jimbo and if we were in a wind tunnel you would understand just by watching the smoke trail off the end plate. The wicker actually bends the air and thus helps the trailing air, behind the wing, remain undisturbed for longer or laminar to be precise. When the flap is not there the air wraps around the edge of the end plate and moves towards the back of the car and if not for seeing it with smoke we would all know it worked but not known why. The air is washed out immediately when it's not there and when it is, it helps the wing (on my car) work better. It does however effect the top end speed by a hair but drag is drag. I prefer the downforce. If I were at Daytona or in a fight with a faster car at VIR that a little more top end would help, I would take it off with a few screws. People will ask if that little thing can effect top end enough to actually make a difference? Imagine that the other car is only 3 mph faster and that equates to 1/4 a car length. Thats 7.5 car lengths in a 30 lap race. This would only apply to certain long tracks with high speed straights and traffic is always a large variable.
I have a video of some testing we just did in the tunnel on a few of our Corvettes and this very principal is on video. I happened to just give it to our production guys to make a little video on how we are doing the real testing in a tunnel for the data we apply to our products. When I get it back I'll post it or give you a link and just by watching you can clearly see the smoke react in two different manners.
Wind tunnel work is so expensive but the data is so worth it.................
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We had a very successful trip to Roebling Road with NASA SE this past weekend. MTI Racing was able to set four new track records between the three of us. (ST1, ST2, TTU and TT2.) If I had the Z there it more than likely would have been five.
The Z is coming along nicely, however we are not going to make our deadline to be able to run it in the Mitty at Road Atlanta this year. We are, in all honesty about a month off and that should include paint and body. I've attached a few new pictures of the front suspension set up and I know you will agree that it is beefy to say the least. The other is a shot of the new tunnel cover we are fabricating for the new T56. In theory it should really improve turn in and threshold braking. It will be a completely new car and I am actually looking at the bright side of not being in this weekends race. If we would have made it, we would have rushed a few things and I would not have had any time to set up the car and test. It's probably for the best..............
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Found a T56 from a good friend of mine today. Needs 2nd gear syncro and some other upgrades to make it live...
Now to find an 8.8 IRS!
Mike,
Try and find the Ford Racing aluminum 8.8 IRS if possible. Obviously much lighter..........
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I appreciate the comments both on and offline and I have no interest in not finishing the car at this point. Everyone knows where I stand and my intentions and goals. We will eventually enter the car in The UTCC and NASAs timetrial series. The series it would classify in allows vehicles based on power to weight. Once the car is shaken down appropriately, it will need other changes before it enters Nasa wheel to wheel racing class, probably Vintage outlaw with Matt or another class...
The project has changed over the years, as have my desires. It is not a street car and has ZERO interior. It is not enjoyable to drive on the street since it is a TUB with rollcage and no sound deadening or interior. It has evolved and changed due to the scope creep that others have so well documented in their responses. I live it, I know it...
Enjoy the updates... More to follow.
I'm likin' the sound of that.........
Richard Lourey has just been appointed Vintage race director for Mid Atlantic. I would make more trips other than my normal schedule if I knew we could go wheel to wheel.
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Keith (RebekahsZ),
In response to your question about my teamate Joe Freda in his "71 F body. He actually has a Jerico dogring 5 speed. His 5th gear is 1:1, he has a Ford 9" with solid rear axle. It has a 326 rear and tops out at 170mph ( He and I both go 164 exactly on the back straight at RA before the braking zone). He runs 18" R1's that are 245 front and 255 rear.
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I love that everyone has the passion and genuine care for each others projects. We post and read threads to educate ourselves and sometimes offer helpful advise to others that are crossing a road that maybe one of us has already crossed, all in the name of helping each other out. We all have different cars each with a different agenda. I appreciate you Mike, for at the very least giving me some credit for having actual data that has taken years to log. I share some, I don't share everything. I don't make changes or do much by chance.The combination of the internals I have are a winning set up. I think that we both are very similar in what we want to achieve out of our cars and in the same environment, so it makes sense for us to follow one anothers lead. You are one of the few people who has ever ridden in my car on track. I actually installed a passenger seat just for that race where I needed your coaching on your home turf. I am looking forward to having my car back on track very soon and in honesty open a whole new chapter in what is possible.
I can only hope that that we all continue to post and ask questions about each others builds. I have seen a dramatic drop off of comments on my thread probably because people don't think my car and their cars have anything in common. I am a Z guy and know a little about the cars. I still read many other threads and enjoy the banter. I know each one of you are wanting to see Mike's car on track and his first post of how wonderful it was that he finished the entire weekend with no oil spurting out from here or smoke coming from there. That post is coming soon.........
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Due to extra room in the engine bay, we've decided to pair up another LS7 in front of this one.
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The tubular structure looks so much like a Z car that I wish you could do all the panel work in lexan so we can see all the magic underneath.
Thats actually a way cool idea to do livery in clear lexan. That is really a great idea. I dont have the money for it but I know some people who do and besides it getting dirty real quick on track, I think it could be something very cool for SEMA.
I agree that the sub structure looks amazing. Thank you.
The picture below shows the slight change in front rake angle and the angry look its going to have when she gets her livery.
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Here's an option for 6-speed sequential transaxle, http://www.ebay.com/itm/GEMINI-CRAWFORD-6-SPEED-SEQUENTIAL-/131151078525?forcerrptr=true&hash=item1e8936a47d&item=131151078525&pt=Race_Cars_Not_Street_Legal
That would get a little more weight to the rear.Any reason you didn't go for a Jerico tranny and save some weight? I have the similar C&R tranny and it's 87 pounds with integrated oil pump. I'm not sure what ECU you are using but Lingenfelter makes a box that works with the stock ECU that allows for no lift shifting controlled via a load cell shift knob. Very similar times to a fully sequential setup. V8 supercars used to run similar with their cars before they went sequential. They used all Motec electronics. Here's the link in case you haven't seen it, http://www.lingenfelter.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LPE&Product_Code=L460135297&Category_Code=C163#.UzTNFPldXkU and a video of it in action, https://www.facebook.com/video/video.php?v=1878619807148. I haven't looked to see if they support aftermarket ECUs but they might.
Looks like it's coming along nicely.
Cary
We, MTI Racing, have our own sequential gearbox as well and it starts with the T56 DogRing. Thats half the equation. If I go to a full sequential and have $27k to spare thats the direction I will move. I picked up this tranny because I knew the owner and installed the tranny. Its one of ours out of a wrecked car and I picked it up for $5k. Could not pass that deal up as it is a $10k piece.
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Wanted to share a few pictures that are very important.
1. The hood is so light I can hold it with my pinky.
2. The structure of the front clip is so incredible that the Gnose just slips right over the bumper.
3. We have made the front bumper a separate piece that is bolted on the front clip. If ever there is an impact it should give at this point and not get the frame rails.
4. Splitter/undertray in front should be very stable in that our nose piece sub structure is strong enough for me to stand on.
5. I took a great frontal shot to show the structure of the front clip without any panels.
I also wanted to point out that we have increased the rake of the front nose to create more downforce. This has decreased the size of the opening in the upper and lower fascia's. We are comfortable that the radiator and supporting coolers will still grab adequate air for cooling. The front looks more aggressive than any one I've ever seen now. It will really be noticeable when the paint and wrap are done.
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We are making progress on the Datsun. I however do not know if the Mitty in 4 weeks is within our timeline. It could be close if we worked non stop but with a NASA SE race at Roebling road in a few weeks and the Corvette motor having to be replaced I just don't see it happening. This new car is going to need to be shaken down more than most and will in honesty be a completely different car than it was, better I'm hoping. It's not like we just put a new nose piece on and replaced some broken or bent suspension. I am looking forward to seeing what she can do when the time comes.
1. I am very happy that we were able to mount the engine as low and as far back as we did. Cg is greatly improved. This required some magic. We also helped the cg in the rear of the car by taking the exhaust out the sides and then we were able to lower the 22 gal fuel cell by 10 inches. Thats huge.... also moved the dry sump tank to the passenger floorboard along with cool suit cooler. By moving the dry sump tank we lost 3 feet in braided lines that were full of oil. Thats more weight than you would think.
2. T56 Dog Ring tranny is in and will be a much needed addition to the set up.
3. Front nose piece supports are in and trying to keep weight minimal. No inner wheel wells really helps. I'm waiting on testing to see where my high pressure areas are before adding any additional vents. The hood cowl looks amazing but I'm thinking it will be very functional as well.
4. Get your orders in now for this hood. It weighs less than 3 lbs and is amazing. No one has seen or had a hood like this in 30 years, This is the first one in 100% Carbon Fiber ever.
5. New CF tail is in and is awesome as well. I am going to have to modify it as the wing uprights and it need fitment modification.
6. I am adding a 102 Throttle body, a fast intake and a new V5 cam to give her a little more umph....
In the picture that shows a frontal view notice that the alternator bracket that I reduced in size for it to fit under my last hood and I still had to have a small gurney bubble in the hood to accommodate it. In this picture, the engine is now around 2 3/4 to 3 inches lower than it was previously. Thats an incredible cg gain.
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I'll be testing this beast out for an MTI Racing customer at Road Atlanta this coming weekend. We have no data on this car and the customer has never driven it. I want to get some base line data so we can turn this low flying brick into something special......
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I was looking at the head on shot. I was wondering if you were going to use a structural skid plate to tie all the suspension together and protect the dry sump plumbing? I'm doing that on my car, which has some similar changes happening. Gotta love how easy it is to get the new parts. BTW, have you checked out any of the ceramic bearings for the hubs? They are in the hundred dollar range but have a let less deflection and friction under load.
I actually had planned on a undertray that will protect the dry sump, however, its main function will be to act in conjuction with the splitter to smooth the underside out. It will not be structural in any way and easily removable for access. I have it designed in a software program and I will search for a picture and share it with you.
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A few pictures of the new front suspension on the Z.
This is what I should have done all along..............put a proper Racecar build on it. The crazy thing is that the hubs and bearings cost me big $$$ for the old Datsun setup. These are 100 times bigger, stronger and only cost $35. You can see we are making our own lower control arms and everything is fully adjustable. BEEFY = STRONG and to think this is going to be lighter than what I had.
This car is going to turn and stop like it never did before.
In a nutshell. This is going to be a completely different car.
You think I'm excited?
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I just couldn't wait to post a picture of the new Carbon Fiber 3" cowl hood for the MTI Racing Datsun 240GTZ. This is fresh out of the mold and hadn't even been sanded or polished. Noboby has seen this IMSA hood in production for over 30 years. The mold was actually found in a barn with some other old IMSA Racing stuff. I know there are some Z Guys out there that are gonna love this......I would estimate that the end cost for anyone that is interested would be around $1200ish in Carbon and FG would be $700ish. To put that in perspective, a CF World Challenge hood for my Corvette is $2600.
I will weight it once it's sanded and polished out.
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I just can't tell you how light the new CF G Nose is..............
The air dam is 1 lb.
Here is one of the guys holding up the Gnose with one finger.
These are 30 plus year old molds and never were intended to have CF Composite in them. When something like this is made it is vacuum bagged to get really good mold adhesion and contour. I made the executive decision to add a little more resin to the edges to compensate for the CF not laying down good. Because in this application the car will be wrapped and the CF is not actually exposed this is not an issue. Function over Form in this case.
I laid some of the panels out and when we get our suspension in place we can mock the panels and at this point I'm leaning towards just modifying the flares outward over the wheels instead of widening the nose and hood.
ALL the credit for these new incredible pieces goes to Brian Kostrba at Z Car Customs in Oregon. He and I have been working hard at the design and layout of these pieces as this is not exactly OEM "off the shelf" stuff here. We have developed a new custom Carbon Fiber 3" cowl hood that I am extremely excited about its look, weight and functional application. It is going to be offered for sale on his web site soon. We are in the process of also offering a 100% Carbon Fiber roof skin that will be not only the single most item for weight reduction you can do but it also is the "no brainer" move if your car is an old sun roof car (like mine was) and want the smooth roof line back. These items are not yet available but when they are and I have them installed you'll be the first to know.
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Keith,
It was great seeing you this weekend and also have you spend time with the team. I'm glad you enjoyed your C7 experience as Barber is such a wonderful layout. I know you were having so much fun looking at all the race cars you didn't get to see my race. Here's what it looked like from in the car. The blue Boss 302 is Dean Martin with Rehagen Racing. They are a Grand Am team and this car is a Trans Am 3 car. He's got me on HP by about 60 or so and I did everything I could but he did a textbook job of defending the line. I am very satisfied with a second place overall in a field of 60 cars. Great weekend.
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In B-ham for business. After my meeting, I hope to visit Kirk Racing and figure our where Barber is. If I deliver the Valentine's goods well on Friday night, I will see you on Saturday.
I'll see you there. I should be pushing off from Atlanta around 1 - 2 tomorrow. Way behind on packing trailer, tire changes aren't done, the weather has really played havok on my schedule. I'll get there when I get there and have fun while I'm there, just might not have a very good parking spot for our trailers. Sometimes we tend to forget or overlook how fortunate we are. I am very grateful that this weekend is going to be beautiful weather and a very fast track. I've been snowed in all week and so far behind on work, I'll just deal with it next week. Bring your helmet as I might be able to manage getting you on track in our C7 track car.
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Very interesting. I only care about fully functional. Last year I ran vertical skirts but they kept getting hit, had to be removed to jack, didnt notice any performance gain and overall were just a PITA. Therefore have been considering changing over to the horizontal ones but hadnt considered lowering it like you did so the front fenders feed it on top. Thats a very good idea. How does the horizontal piece attach?
Thanks for the pics.
If you ever run into issues with the jack. Install a simple jack point by welding a steel female sleeve above the side skirt (through the rocker panel and to the frame rail) that a square male 1" rod can be inserted and then used as a jack mount for the side of the car. While on track it is not attached thus doesn't effect the overall weight of the car. Make sure to weld a small lip or tongue on the edge or flatten it out where the jack will not slip off the bar while up in the air or during a driver change. OR....You could always just install air jacks for $5000.
The aluminum upper piece of the side skirts were formed with cardboard first. I've never seen a 240Z with a straight rocker panel. I determined how low I wanted them by where the splitter and undertray were in relation and if I could get it into the trailer without having to take them off. (I designed and built an aero package for a car once that I couldn't get into my trailer after I was finished......Huge Fail.) Then I cut the aluminum to exactly contour the edge of the panel. I attached it to the seam with rivets and don't be shy as you want to use enough to assure it doesn't bend or give at high speed. I then used 1/2" aluminum angle cut in 2" brackets faced inwards and created a mounting lip for the Carbon Fiber. The mounting points under the car are relative to the car you have. I modified mine greatly by adding two lower 3" steel frame rails to keep the car from twisting in half with 580 Ft lbs of torque. They go from front all the way to the back. I was able to utilize these same rails in tying into the new front clip.
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Zack,
Thank you very much. You are well aware that this is a team effort 100%. I was given the car by my teammate Rob Morrison who had battled back from 5 laps down to put us just 2 off the lead lap. The SC300 guys were a few guys from NASCAR and they were not pleased when I was able to catch they're so called ACE driver. He tried on three occasions to take me out of the race which in all honesty made it just that much more enjoyable. He tried to pit me in 10a the first time, the second he passed me with a wild move that was either move out of the way or well both crash in turn 7 where he dive bombed me (3 wide in 7 is not really ever a good thing). He evidentially got the officials attention with his superior driving skills and after he literally drove me off the inside of 12 at flat out speed right in front of the tower, I had to jump the inside curbing and then out through the grass to avoid serious snap oversteer and the inside wall. This is when his crew chief came to our stall and complained that I wasn't giving him enough room and that I was much too aggressive (imagine that). I think my guys just laughed at him and asked if he needed a fresh diaper or to be burped. Upon his return to his pit stall in his fresh diaper he learned that the officials black flagged his driver for dangerous driving and a warning 5 minute stop and hold /drive through penalty. I was able to hold the lead for another 1.5 hrs of my stint. I was relieved and our next driver (the car owner) had a few incidents (with non other than the Lexus) that caused him to spin 3 times actually and the car sustained some damage. The car gave up on us in our final few hours and thats what they call racing.........
Don't ever be the one that says "Too bad because we could have won"
We didn't.
We will be back for Daytona next in the same car.
Here is a driver change for one of my stints. (SORRY FOR MY LANGUAGE, IM A SAILOR AND I'M AT THE TRACK.) Every team is allotted a five minute pit timer upon entering the pits. You have to use it no matter what so get as much as possible done in that time, but don't rush and overlook small things or get clumsy. We are usually pretty proficient and sitting at pit out at the mark. Don't you love it when the official takes the GoPro off the roof so we get no race footage. We had it on the car in the same location for every other stint. OH WELL.........
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Asking about the side skirt details.
I always start with cardboard templets. SInce the underside of my car is going to be different from yours, mounting points could vary. I stress that if you use the frame rails, rocker seam or something solid always. Remember these will not work if they warp or move around. I would try and get as much under the car as possible over to the tunnel and drop it down with spacers to lower side clearance. If you were utilizing a front splitter and undertray these would all work together to create as smooth as an underside as possible. The skirt should protrude the side of the car in relation to how wide the car is. Flares will help determine width. I found that by not having the skirt extend the entire length of the rocker it allowed for positive pressure exiting the front wheel area to escape. The air then lays on top of the side skirt and does a few things. It provides downforce and helps stabilize the sides of the car. If a front splitter and undertray are in use then it helps keep the air that is being slowed down under the car, it keeps that pressure down and under the car. The rear wheel edge that is exposed should also be taken into consideration. I just took thin aluminum and attached it to the end of the skirt (that we made out of Carbon Fiber) and then cut it to cover that space. You don't want the air on top of the skirt to exit and get into the rear wheel well. I can say that as a rule of racing a proper downforce piece should be able to handle your weight if you stood on it, unless you weight more than 180 lbs. That is not the case with these skirts. You want them as sturdy as possible but the amount of reinforcement it would take to make them that tough would weight too much.
Last point is that side skirts will help with stability in high speed turns but always remember that to optimize the car one needs to incorporate front and rear effect to properly balance the car. A car has to be going at least 80 mph for these effects to even start working. I have tried to work on AERO for my car that is 100% functional and actually helps my car perform better. Almost every piece of aero I see available is for looks and actually is counterproductive and causes drag.
Its all about, if you want it to look cool, or do you want it to be functional?
Here are a few pictures to show what it looks like on my car, how it is not bending at speed and how I first constructed them out of thin lightweight pressboard for testing and fitting. I used aluminum to lower the skirt from the underside.
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You have any pics, dimensions, mounting details, etc you would be willing to share?
Thanks
Cameron
Cameron,
Are you referring to the mounting details and demensions of the side skirts or are you talking about the new front clip and suspension?
Here are a few shots of what we are working on up front.
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Great seeing you this weekend at the Chump-car race at Road Atlanta. Sorry you were having some issues with the car. Still good to catch up........
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We had a great time racing the Chump-car World Series 14 hr. Endurance race at Road Atlanta this weekend. Was able to catch up with lots of old friends and as always make some new ones. We were three laps down when my driving partner took over and he drove great getting 2 of the laps back when he turned the car over to me. I was able to take the lead and hold it for 1.5 hrs of the race. We were looking real strong but had some issues in our next stint which did some damage to the car and with only a few hours to go she gave out. I would guess it was the crank that let go, either way we were done.
Great seeing Hybrid Z member and friend Mike Kelley on track as well.
We had a great time and we will be back...........
That would get a little more weight to the rear.
My Dream LS7GTZ.......project underway
in S30 Series - 240z, 260z, 280z
Posted
I'm good with that. Are Z Nationals there this year? I need to check as we have always had it at Barber in past years. AMP would be good for all the Z guys. My car wont be able to run there due to db but I will at least take it for everyone to see.