Monthly Archives: February 2004

Why Build a Rear Drive?

Why would I want to make a rear drive Talon? Simple – I like racing, I want to go fast, and I do not want to deal with driveline problems. The stock configuration for this car was 195 horsepower, at the crank. That’s roughly 150-ish to the wheels. Last time I was on the dyno in AWD form, it laid down 485 horsepower, and 360 lb/feet of torque. Best ever on the dyno when it was AWD? 491whp. Transmissions, axles, cluthes, propeller shafts, and other parts designed for 195 horsepower don’t typically like taking almost three times the power they were designed to handle. Something’s got to give. So, for the longest time, I just used “street” tires so that something had the opportunity to give. Well, if you’re not getting traction, you’re not going fast enough. The car went 11.18@132.84mph. 130+ is mid 10 second territory, but I wasn’t able to run a 10 second pass. I certainly wasn’t able to drive the piss out of the car, either. I ended up bummed out. Upgrading to something else stock would just be expensive, and I’d still be able to break things I didn’t want to break. On the other hand, I also pondered – I have always wanted a “race car” – the 4g63 has ample power to run 8’s with the right tuning, so as long as I can get the power to the ground, and not have to worry about chassis, suspension, or drivetrain, then I should be all set, right? Okay, so simple, make a rear drive, right? Okay, that’s also not the full reason. I also always wanted something I could bolt monster slicks up to, and just go hammering down the 1/4 mile every weekend in the summer. Something fast, something that showed that skill was put into it, extra ordinary, and something that would piss people off. Okay, so I have a mean streak ;-) I love reeling in big blocks. I like it even more when they think they’re going to catch me on the big end, and don’t. The last trip to the track, I had a LOT of people who normally wouldn’t look twice at an import come up to me and ask questions about the car. I was over a second faster than any other import in the joint, and had 12 mph on the second closest import. Shit, I was running the same kind of MPH that the 10.5″ slick cars were running :-) Okay, so those aren’t all the reasons. The last one? Because I can :-) That’s not meant to be snooty, it’s just me showing my determination. Have you seen some of the cool things Mark Hessler, Rick Garnaat, Jay Danhof, and I have created? It’s just cool. You should see the “shop” we build this stuff in. It’s a regular two car garage. Yeah, we’re cool like that :-) Oh, I’m kind of stubborn sometimes, too. It happens. In addition to that, I’m all about working on stuff like this for fun. It’s a hobby; a passion. It’s what I like. If I had a dream job, it would be building race cars.

Cleaning Up For The 2004 Shootout

Well, the plan was to have the Talon finished, ready to race for the 2004 DSM Shootout. Unfortunately, about a six weeks before the shootout, the outlook of actually having the car completed was very grim. There was just way too much stuff to do to the car, including cleanup, turbo mounting, and all sorts of different stuff. So, we were at a crossroads. It was either time to hurry our asses up, and not make it to the shootout at all, or it was time to clean up the car and bring it down to Norwalk, Ohio.

So, we started cleaning up the car. There were so many things to start gettin squared away, paint, some body work, some more paint, and then some paint. We also needed to finish up engine mounts, and get the fuel cell installed. We also had a lot of rear end cleanup, and the fuel cell cage needed to be made. So, it was time to get cracking.

We knocked out the fuel cell easily – it was already cut up, and just needed to be welded together. So, with that done, we moved onto the fuel cell cage.

But, why would you need a cage for a fuel cell? Well, NHRA rules state “When permitted by class regulations, fuel tanks located
outside body and/or frame must be enclosed in a steel tube frame constructed of minimum 1 1/4-inch O.D. x .065-inch chrome moly or .118-inch mild-steel tubing.” and the fuel cell hung it’s ass down from the framerails completely. So, we ordered up some 1-1/4″ 4130 chromoly tubing, and bent it up for the fuel cell cage. We also wanted to mount the fuel pump and all the lines within the confines of the cage, so that it would all be packaged very nicely. That wasn’t hard to do.

So, we had the cage, and the cell. Now it was time to finish up the engine mounts. This process was a bit slower, but it worked out well. We wanted to create stiff ass mounts, and give them a very boxed in type of look. So, Mark went measuring, and I started welding. I mig welded the mounts to the framerails, and then procedded to box it all in. I think they turned out really nicely.

After that, it was time for pain. I didn’t want to complete the paint on the framerails, because I wasn’t done with them. So, we opted to prime the rear frame, and the fuel cell cage. We also painted the front subframe, and finished up the engine mounts. The new front subframe and the engine mounts were sure to be satin black, because that color just looks cool, along with the new tubular structure for the front of the car where the IC and radiator mounts to the car.

After that, we started priming and painting the interior and engine bay. The interior needed a lot of prep work, and a lot of primer to become nice and smooth. Tons of work, but worth the effort. I chose a GM “pewter” color for the interior and engine bay to complement the red color of the car. I really liked the combination, and received many complements at the shootout and from other people online about the combination, and I was happy with how it turned out.

The other components added to the car needed a different color. So, in the engine bay, I painted everything that we added (engine mounts, subframe) satin black, and then the idea was to paint the structural components of the car a graphite that I really liked. So, I painted the rollcage a Dodge Viper graphite. When the rest of the rear frame is done, I will paint the rest of it the same color :-)

But that wasn’t all. After that, we had a few spots on the car that needed to be touched up. There was a rust spot on the driver side of the car, and a lot of work that had to be done to the passenger rear quarter panel and door. So, Mark and I worked our asses off – and Mark did an exceptionally fine job at working with the paint, bondo, and everything else to get the car looking fantastic :-) Thanks Mark! He’s anal about paint, that’s for sure :-)

Once all that stuff was squared away, we were ready to show our work at the shootout.

Wheels And Slicks

Weld Racing wheels are on all four corners of the Talon. We’re using Weld Racing ProStar wheels, 12×15 inch in the back, and 4×15 inch up front. They’re bolted to the hubs using Weld lug nuts, which unfortunately tend to have really bad build quality. They have immense amounts of thread engagement though :-) These wheels are in a 5×4.5″ bolt pattern, which is identical to just about every Chevy ever made.

Mickey Thompson Slicks

The slicks on the back of the Talon are Mickey Thompon ET Drag slicks. They measure 29.5″ by 10.5″W on a 15″ wheel. These tires are W class tires, which may make it a little challenging to compete in 10.5″ tire classes (most of them around here do not allow racers to use W series tires) – the actual dimensions of the tires are a little larger. I think the trad width on the tire is actually rated at 11.2″, and the diameter of the tire is 29.6″, so they’re relatively close.

Moroso DS/2 Front Tires

The Talon is equipped with 26″ tall, 4.5″ wide Moroso DS/2 front tires. These tires are designed for racing, and have an exceptionally airplane look to them. This is unfortunate, but they still look good on the car :-) I’m happy with them.

Kevin’s bodywork

Back in 2004, Kevin had done a lot of body work to get the front fenders to look a little bit better with the new big slicks that he had put on the front of his car. The stock DSM tires are like 205/55-R16’s, These new tires are like 26″ tall, and 9 or 10″ wide. After getting the axles installed and tested, it was time to finish up the bumper so that Kevin could make some full passes with the car.

So, one weekend (before a race) Mark and I went out to give Kevin a hand with making a new front bumper. It was a good experience for all of us, because none of us had used large amounts of fiberglass in that type of application before. Kevin bought the materials, some fiberglass mat, and fiberglass fabric, along with a bunch of resin, and we got to work. We built a wire frame to lay some fiberglass mesh on, and then layed up a layer of fiberglass fabric. It was really messy work, but it was also a good time :-)

After that, we filled with fiberglass mat, and called it a night. It was late, and exceptionally hot outside. The next day or two, Kevin finished up the mat, and then covered it up with another layer of fiberglass fabric. Then, it was time for some Bondo.

Kevin Bondo’d the bumper, and used it for the rest of 2005. Maybe 2006 will bring a new front clip for the car?

Turbo Garrett GT42

We chose to use a GT42 on the Talon for a few reasons. The most important, of course, was that the GT42 would flow enough air to make the horsepower that we’re looking to make with it.

The GT42 is a small T6 series turbocharger. That’s not to say that it’s small – it’s not – it’s more to infer that this turbo, while exceptionally large, is small in the realm of T6 frame turbos. There aren’t very many other T6 turbos produced by Garrett, aside from the GT45, and the GT60. The GT45 isn’t even listed in their catalog, and I can’t find a part number, but it’s too large for our application anyway. And the GT60? Yeah, that’s a 1600hp turbo, so the thing wouldn’t ever spool on the Talon.

So, we chose a GT42. Why? Well, they’re reasonably priced, easily replaceable, and have been used by lots of fast DSM’ers. If we feel it’s necessary, we can also trade from this standard bearing turbo to the GT42R, a ball bearing version of the standard GT42. It won’t cost anything more than the price of the cartridge. Other reaons for this turbo include not having to deal with 40+ year old technology (all the T4 stuff was designed in the 60’s) and also being able to have something sufficiently large enough to be able to run 30 pounds of boost with good spool characteristics.

Rear End Specifications

The rear end in the Talon is something that I took a lot of time working out. And it wasn’t that aquiring it didn’t go smoothly… The challenge was finding someone that I would be comfortable having build the rear differential.

Through a machine shop that I worked with, I found a place in Lansing, Michigan called K&L Driveline. Bob, the owner and Jeff, one of Bob’s main employees did a great job putting together the rear differential. Talking with them, I could tell they were knowledgable. It was really weird in a way – absolutely anything I wanted, they said was no problem. But, they went above and beyond that, and made sure that the rear end that they built would hold up to what I was going to throw at it. What was it going in? How much torque would it make? How were you launching? Was I using a trans brake? Ladder bar or four link? What kind of brakes do you want? I mean, everything and anything I wanted. And they delivered.

I ended up with a Chevy 10 bolt, 42″ hub to hub, with 4.56 gears, a Moser racing spool, Moser racing 33 spline axles and Moser racing rear cover/girdle. They put the four link bracketry right where I wanted it, the shock mounts perfectly on the axle, and Ford big bearings (This was Bob’s suggestion)- on top of all that, they also had no problems centering the driveshaft on the axle. Sweet :-) This thing was exactly what I wanted. While talking to them, they said that I’d start twisting axles around 850 ft/lbs of torque. I think I’ll be okay.

I’ve been asked – why not have a Ford 9″ rear end? Well, Bob thought that the Chevy 10 bolt was smaller, lighter, and would hold the power that I’ll be putting to it. I’m okay with that :-) If I start having problems, it will be time for new axles anyway…

The Intake Manifold

The runner halves, all TIG'd up, ready to be cut

The runner halves, all TIG’d up, ready to be cut

The runners all trimmed up, complete with taper

The runners all trimmed up, complete with taper

Mark HNC'ing up the manifold flange

Mark HNC’ing up the manifold flange

The manifold tacked together

The manifold, tacked together

4g63 Intake Manifold Flange, Completed.

4g63 Intake Manifold Flange, Completed.

The completed RWD intake manifold.

The completed RWD intake manifold.

Mark and I spent the weekend of the fourth of July 2004 making the sheetmetal intake manifold on the rear drive. What’d we start out with? A four foot by eight foot sheet of 4043 (.090″) and a chunk of 6061 for the flanges. I think the 6061 was 1/2″ thick, but I could be wrong. Well, that stuff, and a lot of Mountain Dew Livewire. We’re addicted. That stuff is way too sweet – we call it “nectar”.

The plan went something like this: I was to do all the sheetmetal work and welding, and Mark was to Hessler Numerically Control up the flanges for the manifold. For those of you who don’t know, Mark is a geek – sometimes it’s a little scary. The flange he HNC’d was accurate to a few thousandths. It fit the head perfectly.

So, Mark plotted out the flange, and I got to work
While he was doing that, I started shearing up the sheet aluminum. Then I made up eight runner halves to weld up to make the runners. After breaking the runner halves, I sheared them to length, and welded them up.

So, I did all that, and Mark was about halfway done with the flange.

Next was the plenum. I’ve got a roll, but it sucks ass, so after struggling with it for about an hour, I resorted to using a heavy duty set of gloves, some muscle, and cursing. A vice helped me out a little bit too. The problem was that the plenum is .090″ and the roll I was using is only designed for like 20 gauge steel – (.036″) so it really wasn’t meant for the job. Lesson learned. After finishing that up, I laid out the rest of the pieces for the plenum, trimmed up the runners, the main part of the plenum, and started getting anxious, so I laid out the oil pan on paper.

When Mark completed the flange, it was time to get welding. I welded the runners to the flange first, and then tacked everything else together.

After that, I welded it up

Mark started the throttle body flange while I was doing all that stuff. When I was done welding the plenum to the runners, I cut up some 6061 to tap for bungs on the underside of the manifold, and welded it onto the plenum.

Mark completed the Throttle body flange, and then worked the throttle body over a little with the mill to clean it up while I welded the throttle body flange to the plenum.