Ok I'm stumped. I've got a b20 vtec motor with a jrsc and the lht aftercooler. Motor was built 6000 miles ago and it keeps running hot. It has a cometic .056 head gasket and arp head studs. It started in the middle of the summer when it was really hot outside. Was running like 220 degrees crusing on the freeway. It kept doing it and I can't figure out what is going on. I've put a full alluminum radiator, replaced the t stat. Still running hot. Did a block test and compression test and both came out good. Tried some water and water wetter and didn't notice a difference. Anyone have any ideas?

 

has the cooling system be bled properly? have you pressure tested the system for leaks?

 

Bled it a few times. Seems to get air back in easily for some reason. Don't have any visable leaks

 

Air back in easily? Does that even sound like it makes sense in a water tight system? Sounds more like you have a blown headgasket...

 

That's what I'm afraid of. I'm not 100% sure that its getting air back in the system. But it passed the block test?

 

Try a leak down test to be safe, I would guess head gasket as well