Hey 'guru... it's been a while since I checked out your thread. My loss I guess! Congrats on getting the car rolling. It's always more than just a little daunting taking it out that first couple times eh? It's hard to enjoy it while your mind is occupied trying to analyze every little tick, clunk, rattle, and vibration wondering if you torqued every nut and connected every hose tightly. Rarely are you so acutely aware of a car being a conglomeration of a thousand parts flying in close formation down the highway as you are when you've built it!

Well done my friend! Well done!

(Edit: Wooo-whoo... I claim page 20!)

[This message has been edited by Bloozberry (edited 04-20-2013).]

Been doing a bunch of driving... this car is rather addictive.

The LS4 factory timing is actually more aggressive that the LS2/6 speed timing (both at cruise rpm and at WOT) so I switched back to the LS4 timing and the car runs better and pulls stronger from the lower RPM's as well. I also reworked the idle timing adjustments to keep the timing table stock from 1400 RPM and above as that is where the engine can be during normal low speed cruise. Eventually I will try adding some additional timing to the cruise cells, but the current setup is pretty smooth and strong.

I finally purchased a new aux gauge housing (all the mounting bolts were broken off the one I had), so now the gauges will stay put during WOT runs.

The car is still pulling vacuum at WOT with the MAP sensor dropping from 98 kpa (ambient pressure) to 94.5 at 6800 RPM. First step was to swap out the filter for a larger 8" cone one:



Unfortunately, the filter change didn't do much to remove the WOT restriction... so the next smallest item is the 85mm MAF. The 4" air intake necks down to 85mm at the MAF then enlarges back to 90 for the throttle body. Since I already have the 4" intake tube, I can remove the current MAF, extend the 4" tube and install a LS7 card MAF. Once that is done, if it still pulls vacuum, then I will live with it. Here are the parts for the MAF conversion (I will have to fabricate the mounting flange for the card MAF):


Another issue I have been messing with is the TCM range switch. I found a wiring oversight in that I didn't wire up the P/N wire to the ECM and just did the 4 wires to the TCM. Added it and it still didn't like it switching from D4 to N via the clutch pedal. Either the DBW throttle would shut off (pushing the pedal did nothing) or it would put the car in low power mode which limits throttle input to about 5%... not much fun to drive. If I keep it wired for D4 all the time, it works great, but sets a check engine code that I can't turn off with HP tuners. So my last plan of attack is to wire up the actual range switch in the 4T65e-hd and manually switch it between D4 and N (or P) in the console area (where the power mirror switch normally goes). Then I will manually put it in P or N when I start the car, then put it in D4 for the actual drive. I think it will also work for a Valet mode if left in N or P as it will likely be in reduced power mode... not that I let a lot of people drive my toys.

So far DoD is still unresponsive. I suspect it is the transmission pressure solenoid doing it. I have tried a couple of resistor setups and it still sets the code. With the code present it puts the transmission in max pressure mode which might keep DoD from kicking in. So I purchased an actual transmission pressure solenoid and will wire it up in the console as well. That should eliminate this code. To address the range and pressure issues, I purchased the range switch, internal harness and pressure switch for a 4t65e-hd:


The only other code is the one for the ISS (transmission Input Shaft Speed). I can't turn it off, but I also don't know how important it is yet. There is no easy fix for this one besides drilling the F40 case and installing a sensor to look at a gear on the input shaft, but the teeth don't match and the manual transmission input shaft doesn't behave like an auto input shaft... so even if I went to all that trouble it still might not be happy and set the code. I am not going to mess with this one until I get past the other ones and see if DoD is happy or not. A sane person would have given up on DoD a long time ago, but I fell off my rocker a long time ago.

I am about through with a full tank a gas where I am tracking my daily commute mileage. Unfortunately, there were a couple of WOT blasts during this tank and I started the tank with the less aggressive LS2 timing at cruise... so I am not expecting any great numbers. It will probably be 15mpg... but it will get better if I can learn to control my right foot.

The last neat thing about the engine/transmission/clutch... I can backup the car in the driveway and in parking lots w/o pushing on the gas pedal at all. I can also smoothly pull from a stop sign in 1st without throttle input as well. The low gearing of 1st, the smooth engagement of the clutch, and the very fast adaptive idle control works wonders. So when I gently release the clutch, it starts pulling the RPM's down slightly (like 50) and the adaptive idle adds timing, which increases torque, which keeps the engine from stalling while pulling the car from a dead stop. I altered the adaptive timing to make it more aggressive at small RPM changes to help settle down the idle with the large cam, but this was an unexpected benefit as well.

[This message has been edited by fieroguru (edited 04-26-2013).]