As many have heard, we're making some pretty big changes to the T1 GTR, and I'm going to outline them here, and answer any questions I can about the new build. It's going to be a relatively long process, and updates may come slowly at times, but I will keep this updated as we progress with it.
I enjoy racing, but even more than that I enjoy building cars and doing new things. The GTR has gotten to a point where it's pretty expensive to race into the 6's, hard to do it very consistently, and progress is slowing considerably given the current combinations. I feel the cars are at a point where they can be lighter, faster, and more reliable, and doing this conversion will both keep me busy with something new, and hopefully result in a contender for the IRS record (currently held by Mark Carlyle at 6.54 @ 223).
I will continue with our proven VR38 engine program, and to start out and get the car sorted, our Forced Performance 80mm turbos. When the time comes for bigger turbos, I'll have Robert at FP cook something up.
From there, we'll have a lot of changes, the biggest being the driveline change.
Making a car with a normal clutch (with limited slipping capability) and a narrow powerband (big turbos on a small engine) leave the line ideally and consistently is very hard. In order to not bog the engine on a launch, you MUST spin the tire a ways out. The new setup will have a torque converter, which will make leaving the line much more consistent, and quicker.
Shane T is a good friend of mine, and a big influence behind this combo (in fact, it was born late at night and many beers in at PRI last year, lol), and has spec'd the converter and gear ratios. I'll blame him if it doesn't work! I'll also be running his MoTeC M150 Drag Package to control all this stuff.
The torque converter is from A1/Quick Drive, in all billet fashion.
Once the power makes it through the converter it goes through a Quick Drive unit. This unit allows us to manipulate converter pressure, adds a trans brake to the mix, and also has a lock up clutch in it. This allows us all the benefits of a torque converter, without the ultimate loss that comes by not being able to fully lock it up sometimes. The system can be made to 100% lock up at any point we deem necessary, controlled by the Motec. Pic coming soon on the Quick Drive.
From the Quick Drive, we go into the Liberty 7 speed transmission. This is air shifted, and will be controlled by the Motec as well. 7th gear is 1:1, so we'll be using all of them. This gear ratio combination will allow us to run very big turbos, with a narrow powerband, successfully, and it will also improve acceleration considerably.
The Liberty trans is a neat piece, it's essentially a dogbox, but the shifting is unique. There is no torque reduction or cut required to shift it, like a normal dogbox. When the next gear is selected, the opposite side of the dog ring is 'engaged' by the overrun from the new gear, and that side of the dog ring is ramped, so it kicks it out of the previous gear. It's kind of hard to picture without seeing it all, unfortunately I don't have any pics of that. It's quite a piece to look at though!
From the trans, DSS will be supplying a carbon driveshaft and the axle and rear end components. It will use a Ford 9" rear end, mounted in the factory lower subframe.
Doing all of this of course negates the need for any OEM electronics, so the entire car will be stripped of all wires and brake system, and rewired by Joel at Race Spec. Between removing all of the OE wiring, brake system, and front drive stuff, we hope to lose quite a bit of weight.
I will also be removing the current cage (10pt, rated to 8.50) in exchange for a proper SFI 25.3 cage.
The front suspension will receive a bit of an update too. The factory suspension will be completely removed and replaced with a Penske drag strut, carbon brakes, and Belak 17x3.5" spindle mount wheels. Paul Yaw will remain the brains behind the suspension and will be updating the front and rear damper spec to suit the new combo.
Marco from Magnus Motorsports is working on the drive adaptor pieces, a flexplate and motor plate, as well as a new dry sump oil pan now that we don't have the front axle in the way to deal with. Since the engine will likely end up in a different location (further down, and possibly further back), the entire turbo setup will be rebuilt as well.
"What's left of a GTR", yeah yeah, I don't wanna hear it. I'm building this for me, and it will further the market in time. While it's more complicated than throwing a TH400 in there, it's no different. It's happened on every other platform out there eventually. The end result of this will be a car that can be raced at national events, on a pro tree, and go rounds. You'll see more of these eventually, and we're documenting all of the development to hopefully eventually be able to offer a package, or parts to assist others who want to step up.
So that's where we are right now, as I mentioned, I'll update this as things progress.