First start

Got the new engine started today.  A registry member came by to experience it with me, which was cool.  Prior to today, I filled her up, and pressurized the oil galleries with Joe Gibbs BR30 break-in oil.  Filled the radiator, and fitted the Dynomax mufflers to keep the neighbors happy--only slightly.

First crank, fired up pretty quick.

It's very hard to get these motors to burp the air out of the cooling system on the stand.  I have not (yet) tapped bleed fittings in the coolant outlet pipes on this engine.  I have however already blocked off the coolant passage in the plenum.  Passenger side had good water circulation, but the driver's side did not.  Coolant pipe would not get hot enough to indicate water flowing out from that side.  After this first start, I disconnected the 90-degree elbow from the drivers side and forced air into the system, blowing into the coolant crossover tube until hot water finally came out from the driver's outlet pipe.

You might also see smoke from the exhaust on the driver's (left) side.  When I pressurized the system, I forgot to install the cam sensor, and the resulting oil leak poured down on the exhaust header.  Doh!  Will take some time and heat cycles to burn off all the oil residue.

Here's another video I took later in the day,

After it all cooled down, I performed a cranking compression check, and cylinder leakdown test.  The cranking compression for all cylinders was remarkably consistent, just over 240 psi-- a good jump over Build1. Leakdown rates were even more impressive.  All cylinders were less than 2%, despite not yet getting any load on the rings to seat them in properly.  There was much worse and scattered leakage values on the old build.  All over the map, 6% to 18%.  I am going to give credit to Ross pistons, Total Seal rings, and the machine shop for nailing the cylinder finish.

Oil pressure was ~60psi at idle, and the wideband indicated we were a little lean, but that might be a function of the cam overlap at idle.  Once I opened the throttle and brought the revs up, it richened up.  Alternator isn't charging, so I need to figure that out, but otherwise I'd call it a successful day.  Now off to the dyno!

Getting Closer.....

Getting closer to the first fire!

Cams timed.  109/111 centers.  A degree allowance for wear/chain stretch.  Using the new high strength cam chains co-developed with Jerry.  I've now got the new build on the test stand to finish assembly and fire it up.  Hope we can have a local get-together when the time comes.  Then off to the engine dyno!

Minor issue with the new fuel rails.  I need a very low profile 90-degree elbow to clear the throttle linkage on the driver's side.  It's a very tight space to run the crossover line from left rail to right.  I plan to fire it up with the stock rails until I can sort out the new parts.

Also, replacing all the plenum vacuum nipples with NPT pipe fittings.  Pics to follow.

New Fuel Rails and PRV

As I said in a previous blog post, we had trouble getting enough fuel to the first 427 build at 700 chp.  I believe the fuel system was not up to the task, so contracted Kinsler to develop new rails capable of feeding more than 800 chp.  These are custom made and feature .685" ID, with -8AN inlets and outlets.

I will have to run new lines from the pumps to the rails.  Will feed the fuel inlet into the drivers side with -8AN line.  Connect the two rails in the front--there is no A/C compressor in the way, so plenty of room to route the line.  At the end of the passenger side rail, I will connect the pressure relief valve, set to 75psi.  A -6AN return line will send the excess fuel back to the tank.

With the relief valve set to 75psi, my 30lb Red Motorsport injectors will flow the equivalent of 44 lbs/hr-- enough for over 1000chp.

Mid-winter update

You guys are probably wondering where I've gone.  No posts since September on this project.  Had to spend some time doing other things in the fall, and now it's just too damn cold out in the shop to do much.  Nonetheless, some things are moving forward.

• The cylinder heads are installed on the shortblock, torqued to 120 lbs-ft (ARP studs).  Cams and lifters are in place, temporarily.

• Degree wheel is installed, ready to time the camshafts.

On the advice of my camshaft supplier, I will slightly modify the cam timing to suit the new intake flows and higher compression (14.5:1 from 12:1).  New timing will be ICL: 109 ATDC / ECL: 111 BTDC.  This compares to 107/109 on the first build.  Perhaps idle quality will be a touch better with the less valve overlap.

• Fuel system design continues.  This includes new rails with larger ID, and a new regulator to bump fuel rail pressure to 75 psi.  The Bosch series III injectors handle that pressure just fine, and the better atomization should help combustion efficiency.  We will feed the rail with -8 supply lines (1/2" ID).

• Crankcase evacuation strategy continues to develop.  I am convinced the main issue with the previous build causing oil in the combustion chambers, was due to the flow through the stock PCV system.  At idle the manifold vacuum was sufficiently low (~60-65 kpa) to prevent the valves from closing, thus allowing significant oil and vapor back into the intake manifold.  This time around, I plan to vent the crankcase directly to a catch can.  I'd appreciate feedback from anyone who's done this.  I know it was done successfully on a recent LT5 for racing application.  At 14.5:1 compression, the combustion chambers have to be oil-free.

• The calibration and datalogging setup continues to mature.  I will initially use Tunerpro RT with a custom dash, including a new ALDL stream to monitor exactly the variables I want (such as commanded Lambda).  A NTK wideband output, and a dedicated fuel pressure sensor will be fed into the stock ECM for monitoring.

• And lastly, in a few weeks the top end pieces (plenum, airhorn, cam covers) will be going out for powdercoating.  Not real urgent on that one.

Until next time.