The GTM Supercar Build Log

Archive for February, 2009

Engine Dyno Tuning and Install

Saturday, February 28th, 2009

As promised, here are pics and vids of the dyno adventure.

It was a long day, but a successful one. Once we finally were able to try to run the engine it pretty much started up instantly – Brian (the guy running the dyno) jumped in surprise. I don’t think that happens often. Every pull was strong, and we got a great tune out of it by the end of the day. This program was then copied over to my PCM so the engine is ready to rock. 623.8HP @  6200, 572.8ft-lbs @ 5100. The engine has loads of torque and never goes below 500ft-lbs from 4000 through 6400rpms. It’s average torque from 4400-6400rpm was 555.8.

When we got to Hitech Motorsports we had to drain the oil out and change the windage tray from the LS2 version to a newer LS7 version. Brian informed us that the longer pistons may hit the ribs on the LS2 windage tray, so we swapped that out. After getting the engine mounted in the dyno one of the main power cables on the dyno shorted. It could have ended up very bad, but luckily Brian was able to fix it and get us running.  This motor was previously a dry-sump configuration, so we had to take off the valve covers to fill it with oil (afterwards Hitech traded me my valve cover without an oil fill port for one that does).  This wasn’t a pain since we had to take off the intake manifold to rotate it back to its normal configuration anyways due to the engine dyno not being compatible with a rear facing intake manifold. Minor drama, long day, very successful. It is comforting to know that this engine will run great once the time comes. GREAT work, Erik. 

Once we finally got back to the garage we ate some great stew my wife made Erik and I, unloaded the engine, installed the motor mounts, put on the clutch pressure plate and flywheel, and got it set in. Finally! Thanks for the help, Josh!



Engine Runs Perfectly.

Saturday, February 28th, 2009

Too tired to type much – long long day today. Got the engine tuned on the engine dyno and it put out 624hp, and 572ft-lbs. Will update with pics and vid later.

Engine is Ready for Dyno

Thursday, February 26th, 2009

Engine gets tested, dyno’d, and tuned tomorrow.

AC Wiring and Organization

Monday, February 23rd, 2009

Finished wiring up the AC connections (B+ and a few grounds). Afterwards I removed the zip ties holding the front end wire looms to the frame and fastened them into place with some retainer clips.

Engine Harness Prep + Engine Update

Saturday, February 21st, 2009

Tonight I prepped the engine harness for installation. Since the intake manifold is backwards on the GTM the donor harness has to be stripped down a bit and some plugs need to be ‘freed’ from the harness so they can reach over to the new sensor locations. In a nutshell, each bank of injector plugs need to be stripped out and the other plugs that are bundled with them need to be retaped separately. This was a mindless task that allowed me to catch up on re-runs of Raymond, King of the Hill, and Malcolm in the Middle while I worked.

Got some engine pics from Erik today – the rebuild is going as planned and we are looking at possibly getting it on the engine dyno for testing and tuning next Friday.

Duct Holes in Top Footbox Panel Aluminum

Saturday, February 21st, 2009

To accommodate the duct hosing from the evaporator, holes need to be cut into the top panel of the footbox. I made a cardboard template of the aluminum panel first, then used it to cut out the holes freehand with the Dremel. Afterwards I smoothed the edges down – I will pick up some serrated grommeting and line the edges of the holes as well.

Clutch Line

Thursday, February 19th, 2009

Plumbed and set the clutch line in place. Once the transmission is installed the final bit of line will be ran to the slave to finish things off.

Engine Update

Thursday, February 19th, 2009

Erik is finishing the engine build this week. Next week we will most likely be taking it to an engine dyno to have it tested and tuned for installation. Barring any surprises, possible installation next weekend!

Thermotec Heat Barrier

Tuesday, February 17th, 2009

Today I applied Thermotec adhesive-backed heat barrier to the fuel tank cover panels, engine cover, and the entire interior of the tunnel. This will reduce radiant heat greatly and keep the interior of the car much cooler. The barrier is very easy to apply. I will most likely cover the interior of the dash console when it is ready for installation as well.

Wiring Cleanup

Sunday, February 15th, 2009

Spent today cleaning up the tunnel wiring. All the wires running through the tunnel, as well as the window switch wiring are now all self-contained in their own corrugated loom. Nice and clean.