Jim Green's 90q 20vt - 636whp 07k

[audifreakjim]

just feed and caffeinate me.

Fixed that for ya

Nice work on the diffuser, love the dividers. Please keep us posted on how well this works. Something like this is in my future.
So might as well come out with it: Would it be aaaaaalright if I copy ?

Definitely! I added a few NACA ducts by the rear diff to help keep that are a cool, a duct to the fuel pump and cut out the area under the battery to keep it cooler. I'll grab some more pics, but it should not change airflow too much.

I am extremely pleased with the performance, 153mph feels great. Before 130mph felt sketchy. 160 is my goal around Autoclub

[Einbilden]

Thanks ,and yes more pictures please. Hope you get to 160mph with your car! Don't know if you have gone that fast in a automobile but I do know that 1 inch of steering input equals lane change at those speeds.

[audifreakjim]

Here are the cooling ducts to the diff and fuel pump. They definitely help the trapped air in those areas, pretty sure this is all good to go.

[Afterthought]

Reminds me of the bottom of a R8, but much better because its a widened B3 90 Q with an 07K

[pilihp2]

that is just fantastic.
I'm not sure why, but Aero and functional bodywork gets me like 10 times more excited than just a big turbo
Except when I'm driving that car with a big turbo.....


All the other time though!

[audifreakjim]

It's nice to spend some time on things other than the engine. I think a roll bar is going to be this summer's project before BBQ. Then it's time improve the driver instead of the car

[pilihp2]

It's nice to spend some time on things other than the engine. I think a roll bar is going to be this summer's project before BBQ. Then it's time improve the driver instead of the car

I for some reason thought you already had a roll bar...?
Are you thinking a fully custom one, or a somewhat universal one that requires minor modification to fit?

[audifreakjim]

No cage yet. Full custom, I'll probably buy a bender and do it myself. Rear hoop, one or two diagonals to the rear, harness bar, and a single door bar going from the front wheel well to the middle of the rear hoop.

Basically as much stiffness and protection as possible, but still safe to drive on the street without a helmet on.

Something like this but with more diagonal bracing

[the german]

Nice! I fully encourage doing it yourself. If you're anything like me you will probably mess up a few bends getting it just right, but it's more fun to do it yourself

[Einbilden]

Great job on the aero, those ducts look awesome and make that look factory. Thanks for the pictures and the inspiration.

[Rennkafer]

Don't know if you follow the Fabrication Series on FB (and Youtube), Jim but you should go have a look if not. Justin goes into a fair amount of detail on how to properly build cages (and by extension roll bars). He also just bought a new bender (RogueFab Model 600) and loves it... and that's coming from a pro fabricator who's also had a JD2 and a Tubeshark. I have the same bender, and assuming you can weld it together, it's a great deal. $650 with a die set. They're air over hydraulic and since it bends upwards rather than horizontally, you don't have to anchor it to your shop floor.

[audifreakjim]

Yeah, I am considering that one partly because you mentioned it before:) honestly I think I only need the main hoop built. I plan on mocking it up with 1/2" conduit and seeing what a fab shop will charge to build that piece. After that it's all strait pieces.

[the german]

^ you will also need A-pillar bars bent which are trickier to nail as the bends typically are not in plane like the roll hoop. If you do a halo style design, you will need to get the halo bar bent too, and maybe door bars depending on what you decide to do there. Other than that, it's all straight pieces.

Edit:
That applies if you are doing a normal cage. I guess I don't really understand doing just a hoop as you are already most of the way to a real cage which offers much better protection.

I don't want to preach, but I'm a big proponent of running a full cage if you are on the track. A friend of mine (an extremely talented driver with over 40 years of racing experience) was killed two weeks ago when he went off track in a vintage sports racer that had only a roll bar. Not worth it to me.

[jretal]

Yeah, I am considering that one partly because you mentioned it before:) honestly I think I only need the main hoop built. I plan on mocking it up with 1/2" conduit and seeing what a fab shop will charge to build that piece. After that it's all strait pieces.

That's what I ended up doing w/ mine... I was all about trying to figure out how to use a bender, etc... but when I called the local shop that did mandrel bending (mandrel bending solutions is an hours drive from me), they quoted me $100. For that, I couldn't say no! A couple other shops wanted to charge like $300, and this literally took the guy 30 minutes to do. I measured everything out and drew it out, and he entered it into their software (Bendtech or something like that), and it told him where to put the bends, etc. Stupidly simple!





Just make sure they enter the proper material into the computer, as it affects the bend back (i.e. Chromoly has to be bent slightly further than regular DOM in order to retain the same angle). Otherwise, you get something like this Leg on right of photo compared to left...



Also, do yourself a favor and get a tube notcher. Doesn't have to be overly fancy/expensive one, but as a lesson learned, it would have made my life a LOT easier when doing the cage in my 4000. Otherwise you're using an angle grinder and grinding/cutting/notching PVC piping and making funky patterns like this:

[ringbearer]

^ you will also need A-pillar bars bent which are trickier to nail as the bends typically are not in plane like the roll hoop. If you do a halo style design, you will need to get the halo bar bent too, and maybe door bars depending on what you decide to do there. Other than that, it's all straight pieces.

Edit:
That applies if you are doing a normal cage. I guess I don't really understand doing just a hoop as you are already most of the way to a real cage which offers much better protection.

I don't want to preach, but I'm a big proponent of running a full cage if you are on the track. A friend of mine (an extremely talented driver with over 40 years of racing experience) was killed two weeks ago when he went off track in a vintage sports racer that had only a roll bar. Not worth it to me.

Sorry to hear about the loss of your friend, I second the full cage.

[Mcstiff]

This has taken an interesting turn, there is always the token "don't drive a caged car on the street" guy but now we've determined that everyone needs 2 cars.

[pilihp2]

If only there was a legitimate way to make a full cage, with a removal front section for street driving.
can never have everything we want.

[audifreakjim]

Justin, thanks for the pics, every example helps!

As far as putting in a full cage, it's hard to argue against it. At the end of the day, a good roll bar is what is the best fit is for this car

[the german]

I forgot this was a street car and not just a track weapon. With a full cage you need a helmet, which is pretty silly and annoying on the street. You're right- roll bar makes the most sense for the car.

[jretal]

Justin, thanks for the pics, every example helps!

As far as putting in a full cage, it's hard to argue against it. At the end of the day, a good roll bar is what is the best fit is for this car

No problem! I have more in my 4000's build thread. I had mimic'd the structure on mine to match what my buddy had in his GTS3 M3 race car.

As for the rear cage vs. full cage... it's def a toss-up, and can get argued both ways. With the speeds you're hitting in that thing, having something that will keep the roof off your noggin' and keep you planted in the seat is a must. The rear hoop helps, but won't be 100%.

There are ways to make it very modular (i.e. full cage when you need it), but then you're at the mercy of the joints to hold in an issue. I designed my rear cage to be fully removable, so when I want to fit 4ish people in the car, I have 12 bolts and 2 strong people and I have my back seat back. That being said, the rear seat hasn't been back in the car since I did the cage... lol. Might change w/ 2 little kids and a desire to use the car more than collect dust, but that's a different conversation In the end, it's all about checks/balances and what you need/want, and the "risks" you're willing to take. Whatever you put it, it'll be better than what you have currently!

Look forward to what you come up with, Jim! You looking bolt in? Or are you welding in directly?

[ChrisAudi80]

Any updates, Jim?

[audifreakjim]

Just spun a thrust bearing from low oil pressure/big clutch and destroyed my transmission due to user error when shimming the bearings. I think I have finalized a roll bar design though.

[Afterthought]

Damn sorry to hear about the engine issues I have been there

[chaloux]

lol. yeah, no biggie, just an engine and a tranny, simple stuff

[audifreakjim]

I have the replacement transmission, engine will hopefully be done in two weeks. I'll keep plugging away at the roll bar. Just need to power down and weld some shit.