Nissan 370Z Forum - View Single Post - Problem with VQ37HR

GodISmE · 03-02-2021, 06:45 AM

Hi, I checked valve lash becasue compression was way too low, especially on cylinder 1. My intake cam lash went down to 0.05-0.15mm, so quite a lot! Exhaust side is fine, around 0.30mm on all of them. This is just after 1000 miles done on tracks (track car only). HR Heads were fully refurbished and lash was set at 0.25mm int., 0.30mm exh. Stock HR were used so I suspect this might be the problem. But I want to understand why - is it just the fact that they are two soft compared to upgraded Tomei springs or is it their compressed height? Or maybe somethings else contributed to it?
Any experienced engine builders here?

Cams are Tomei Procam 280/11.3 and 272/11. CP pistons 95.75, 11.6:1.

03-02-2021, 06:45 AM	#1 (permalink)
GodISmE Base Member Join Date: May 2017 Location: Poland Posts: 3 Drives: 350z Rep Power: 8	Problem with VQ37HR - Tomei 280 cams, CP Pistons Hi, I checked valve lash becasue compression was way too low, especially on cylinder 1. My intake cam lash went down to 0.05-0.15mm, so quite a lot! Exhaust side is fine, around 0.30mm on all of them. This is just after 1000 miles done on tracks (track car only). HR Heads were fully refurbished and lash was set at 0.25mm int., 0.30mm exh. Stock HR were used so I suspect this might be the problem. But I want to understand why - is it just the fact that they are two soft compared to upgraded Tomei springs or is it their compressed height? Or maybe somethings else contributed to it? Any experienced engine builders here? Cams are Tomei Procam 280/11.3 and 272/11. CP pistons 95.75, 11.6:1.