Need help! Motor is tough to start...
 

Title says it all, I'm having a tough time starting my car at what seems to be random moments. My motor is fully built n/a LME 440, compression is 11.8, and a pretty hefty cam. When the car has been off for a while (a few days or more), it starts up with relatively no issue. Then I'll go ahead and drive it and get it warm, shut it off, give it time to cool and then it'll take a good 5 seconds or so to start, and it barely starts. I thought it was the starter because I know of that whole issue but I had the started tested and it tested fine (also installed a heat shield and the problem still exists). Funny thing is though is once the car finally does start I can shut it off and start it again pretty much immediately with no issue at all. So I'm wondering if I have a fuel issue or something? The motor is running really rich right now for a break in period by the way. Anyone have any idea where to go from here?

Slow crank, or cranking normally for those 5 seconds until it fires? When it does fire, you say "it barely starts"...does it run rough for any period of time?

Try cleaning the large ground next to the starter going to the block then to the frame.

Need more info like defining "hard to start" and "barely starts." Does the starter turn the engine over at a normal speed, but you have an extended period of time before it actually starts running or does it crank very slow (as if a battery was low on charge) and then eventually start cranking fast enough to start?

Also, I didn't think a really rich running engine was a good idea during break in, especially when trying to get rings to seat.

If it grinds like a low battery, then it’s an ECU timing issue at warm start. Timing is to far advanced for a hot start. Dealt with this in the past. I’m assuming yours got a tune, part of the tune needs tweaking.

:iagree: If the starting system is healthy, it's a tune issue (very common!)