It's true, I did just rebuild it earlier this year. I thrashed away for 2 months to get it back together for the GG and USCA events in March. After I made my selections and had parts rolling in, I discovered a few things which I wish I had done differently. I just didn't have the time to make the changes and still have time to make the events.
Fast forward to July. Eric and I have been trying to fix a vibration in the driveline at speed on the highway. We determined that we were going to have to make some changes to the torque arm to address it (we had no adjustability the way it was). So TOW went back to Eric's, and we developed a plan.
As these things tend to go, the scope of the project grew. Ron Sutton and I have been talking for a while about ideas on how to install a sway bar on the rear of TOW. With everything I have going on under the car (torque arm, Watt's link, exhaust over the axle), there was just no good place to mount one. But after seeing a couple of other people run bars through the trunk (typically more race or hardcore applications), I started thinking about ways to do that with TOW. And Eric and I came up with a plan.
I'll give more details on all of that work later, as it's still a work in progress. But the point of that background was that TOW was going to be down for a few weeks. One thing led to another, and I decided to take the opportunity to address the things I didn't get to do in the engine originally. I knew I would have the time, and so I dove in.
The list of changes I'm making to the engine:
- Low-Lash solid roller cam (slightly bigger and a bit more overlap, targeting mid-range torque)
- Crower Solid Roller lifters
- Crower Stainless Steel Adjustable shaft rocker system
- PAC 0.700" lift double springs (just a small step up from what I had)
- Holley billet fuel rails
- FIC 62# Fuel Injectors
- 1/2" carb spacer under the throttle body (more plenum volume)
I debated heavily whether or not to do this, but it turns out that I'm glad I did. When I started the disassembly, I found some oil in the intake runners and plenum. With just 2k miles on the clock since the rebuild, this was concerning, especially since I wasn't yet running my PCV setup. Turns out that I didn't seal the threads on the rocker studs, not realizing that they opened up into the runners. I found some pretty caked on burned mess on the top of the pistons which I proceeded to scrub off. Lesson learned.
I carried the heads back up to Frankenstein who ported and assembled them originally and had him clean them up and set up the new springs. Oil issue aside, he really liked what he saw from the burn pattern on the heads. We didn't see any signs of reversion in the ports either, but we could tell that a couple of cylinders were running rich from the exhaust ports. I recalled that I purchased and installed a set of fuel injectors used, without any data on them, so I decided that I would replace them with a new set that are flow matched.
I ordered the new cam from Kip at Cam Motion after a couple of conversations with he and a few others in the LS community. Kip has been building these low-lash solid roller setups for a while, and several people seem to be running them on the street with good success. For me, I'm looking for an increase in my midrange torque production for the events that I do, but I'll also get some more RPM out of the motor with the solid valvetrain which will help with the 1st gear autocrosses. I'm looking forward to the change!
So this past weekend was reassembly time. I spent 2 full days at Eric's getting the cam in, degreed, installing the heads and reassembling the core support items (oil cooler, condenser, radiator, PS cooler). Took longer than I expected, and I'm not done, but I'm held up needing to get a new set of pushrods now). I'm ordering those today, should be able to put it back together next week. I still have time as Eric will finish up the suspension work this week and get parts out for powder coating next week...
I did this as much to satisfy my curiousity about this SR setup as anything, and frankly I needed something to tinker with. Hopefully I see some nice gains from it without giving up too much drivability. I'm not too worried given my research. And TOW needed a little more 'growl'.
I'll update more soon with pictures of the rear suspension work once it's closer to wrapped up. Softening up the rear springs is going to make those Fort Worth drives a little more pleasant. It should also help plant the rear a little better coming off the turns. At the Optima USCA event, things were squirrely (as proven by one of my jaunts off course), so this should definitely help!
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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