Neil20vtc 44 Posted August 25, 2017 Report Share Posted August 25, 2017 I'm in the process of trying to solve a running issue with my vrt and Ive done a cylinder pressure test to rule any headgasket/ piston ring issues test was done with engine upto temp and I'm running a spacer to make comp 8.5.1 All cylinders were between 100-110 psi , is this ok as I know what psi it states in the Bentley but this is for a standard compression vr and I'm hoping my figures are ok due to lowering the compression of the engine for going turbo cheers Neil Link to post Share on other sites
vr6turbo 27 Posted August 26, 2017 Report Share Posted August 26, 2017 whats the running issue ? was the head rebuilt how many miles has the engine done Link to post Share on other sites
Neil20vtc 44 Posted August 27, 2017 Author Report Share Posted August 27, 2017 Been running rich but I think I've narrowed that down to a warped flange on the turbo to manifold adapter I made letting some gasses out I just wanted to double check the cylinder pressures are all good as I've taken the car off the road to freshen everything up and it would be easier to do any work on the engine when it's removed the head wasn't rebuilt but was skimmed when removed for fitting the spacer and new stem seals were installed and the engine has covered 116,000 miles Link to post Share on other sites
vr6turbo 27 Posted August 28, 2017 Report Share Posted August 28, 2017 That works out at 125 psi with the 8.5 to 1 ratio you are runningThat's if we take the lowest acceptable stock compression of 145 psi. So your compression is a bit down. I always inspect and regrind the valves in when the engine milage is more than 100,000 that could make a difference to your compression If not it's got to be the ring's A leak down test is the way to go to determine where the compression is going Link to post Share on other sites
vr6turbo 27 Posted August 28, 2017 Report Share Posted August 28, 2017 8.5 1 is 15% lower than stockStock should be 10 to 1 Link to post Share on other sites
Neil20vtc 44 Posted August 29, 2017 Author Report Share Posted August 29, 2017 Cheers for the replys mate from what I read in the Bentley the stock compression figures when new are 160-189 psi with a wear limit of 109 psi, either way I'm still right on the limit sorry forgot to say I also cleaned the valves and lapped them in ill look into into doing a leak down test Link to post Share on other sites
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