This was going to be a short post to talk about something else but I kept rambling about the car so I'll just make two posts.
I wouldn't be a car guy if I didn't make a boring cold start idle video so here you go -
I drove the car 2 hours yesterday and spent 15-20 minutes in miserable LA traffic. The 15N to Vegas is down to 1 lane and everyone was trying to get there for the superbowl. I moved my IAT sensor and epoxied it into the intake manifold and it works phenomenally. The IATs sitting idle climbed from 75-80 up to 150+ and the ECU kept everything perfect. I could feel the self learn continue to do its thing and get better the longer I was idling around. Cooling performance was great with the electric water pump keeping coolant temp below 200 with a 185 thermostat. The cooling fans also didn't impact the engine tune like it did before with the MAF sensor.
The tune continues to improve everywhere and honestly drives quite well right now. It'll buck like mad if you don't give it throttle on take-off so I need to see what is causing that, but if you give it some load the car drives very smooth. It also tries to stall if you clutch in from too high of an RPM so I need to either slow down the drop, or make the catch more aggressive. It is a bit of a mind-f to tune on the tables in this car because of the giant 105mm throttle body. It idles with this cam around 65 kPA and when you first give it load it drops to 30-40 range, but from 40% throttle position you're back up to ~90kPa. I have this giant fuel and spark table but it feels like it spends most of the time in just a few rows. Because of this I've found some areas where I had spark jumping 5-8 degrees as it goes in unexpected directions in the table causing bucking so I just need to continue to manually review these trouble spots and improve them.
There are some light chuggles when going on/off load in low rpm regions, but I also have extremely low driveline intertia with the RPS clutch and it honestly always did this with the smaller cam and the e40 ecu as well to some extent. I need to experiment with more/less timing in those areas and see what it likes.
I got my fuel pressure, flex fuel and speed input all working in the Holley. Still struggling with the tach - worst case I can buy a dakota digital converter but I really feel like I should be able to get this work via the Holley. I can't believe they output an 8cyl tach output that isn't programmable when so many of these go onto LS engines. I've burned enough fuel now that I can throw in some E85 and start playing with that. It won't be night and day power gains, but at 11:1 compression making ~600hp I think e85 will help it out some especially in the midrange and part throttle high load regions. It also keeps the engine cooler while hammering on it.
Power is insane and the powerband has never been as broad or as smooth. This is definitely feeling like a very optimized engine package now with the "proper" duration camshaft for the engine combo. It is a pretty big dickhead machine, but as the tune improves it is mellowing out some. The easier it is to drive the less I feel like it draws attention at low speeds.
My dad took it for a spin while I rode passenger and watched the logs. It pulls very hard to 7200 and even if you short shift it at 6700 it doesn't feel like it loses any momentum. Estimation is it is solidly a 135+ mph trapping car right now making it faster than our 9.9x drag car with a 416. Power is still very manageable on these Maxxis slicks, and the car gets your heart racing. The way the power is delivered from the FD right now is very impressive. All the work I've done to the driveline to improve efficiency and smoothness is finally paying off. For an engine with dead stock ls3 heads I couldn't be more impressed with the performance.
I noticed my 275 wide 18's are rubbing on the inner fenders up front. I also haven't been thrilled with the steering feel on the street for the giant tire. I think in the future I'll throw a 255 up front on the 9.5 wheel it'll fit better and the slight stretch should improve steering response. I loved the steering feel of the 255/40/17's.
I also want to schedule a corner balance and alignment appointment. I'll probably reach out to CHE Works for anyone in Socal that knows who I'm talking about. I corner balanced the car myself when I first got the car together but have made tons of changes since then. The car has always been a little ass-down in the rear which improved the cross weight and f/r balance - but I don't think is the correct way to setup the car and it always looks a little off. I could also use a little more ride-height with the 18's and I want more camber so I can put my spacers on in the rear and take more advantage of these tires all around.
Here's the dirty girl still with the road grime and snow residue from when I blew the coolant surge tank in January 2020 up on Angeles Crest lol.
