Quote Originally Posted by Gojira94 View Post
Haven’t touched it for 12 days until tonight, very brief time spent. Cleaned up the spider I acquired from a boneyard LT1 D body. Also soaked the new lifters in virgin mineral spirits for an hour to clean them. Blew them dry with air and put them in the oil bath until tomorrow evening.

What I have been able to do is study the hell out of VE and spark tables from a variety of engines similar to what I’m putting together. I’m most familiar with F body LT1s. With a 218/224 - .528/.535 cam in 185cc aluminum heads I’m not too far away from an LT4’s flow characteristics. I’m a tiny bit bigger on cam, tiny bit smaller on heads (heard LT4s were 190cc heads, maybe not accurate). My goal is to put together a better 2nd attempt on the VE tables and take a stab at the spark tables in the bin and upload that in a couple of days. Scrutiny of more experienced guys would be welcomed.
LT4 heads are195cc with 2.00/1.55 valves. Their smallish chambers have them at 10.8:1 with the flat top piston. The cam is 203/210 @ .050 and they run 1.6 roller rockers from GM.

I have 205cc copies of Dart Pro1 Platinums on the L31 in my Express van. With a 215/224 cam and 1.7 roller rockers. With the MAF disabled I had to add a good bit of VE above 2,500 rpm. With SD disabled the MAF only required slight tweaking in the lower rpm, lighter load areas to get the fueling back to optimal. Once they were both fixed it was noticeably smoother and stronger across the whole RPM range. Converter stalls 2,500 rpm and I have 4.56 gears with the 30.5" tall tires. I turn 2,600 rpm @ 70 mph in OD. With the travel trailer in tow I have found any real grade has me in 3rd @ 3,500 rpm and if the climb is long enough or steep enough I have plenty of RPM left in 2nd gear if needed as well. 2nd puts me at 5,200 rpm @ 70. My shift points in Tow/Haul let it grunt a bit though and I do not downshift to 2nd unless I am under 65 mph in Tow/Haul.