BOB.T

Hi, my mate has a kit car fitted with a 1740 X-flow which is breathing a bit. He's done a compression check and is getting no higher than 70psi I'm not really sure what you'd expect to see, surely it'd be nearer 150 or so?

Would anyone care to comment, please?

Harrymattson

Breathing a bit you say??

Without teaching egg sucking - I assume that all four pots record 50 PSI whilst cranking with all plugs out? Try the usual trick of pouring a table spoon of oil down the plug hole to see if the compression is altered which would indicate a ring probelm etc.

My old X Flow running 10:1 CR recorded around 150 PSI if that helps?!?


Cheers
Matt

BOB.T

erm yeah, just breathing a lil bit

All the tests were done via a phone link up I got him to try some oil, he said they all went up a bit...very precise I know He did check all 4 pots btw

I'm gonna suggest trying my gauge on it some time this week, just to comfirm things

Alan Ramsay

150 - 200 is more normal, 70 is too low, time to take the head off I think

BOB.T

Yeah, I think that's the next step too

Harrymattson

I'd try another gauge first Bob - If it had a mechanical prob I would not expect to see all four pots down at 50 PSI - seems sus to me mate! Don't go removing heads or sump yet me owd!!


Matt

BOB.T

He's done it again and is getting 150 now, work that out!

Harrymattson

Operator error with the gauge, not taking the other plugs out, not having the throttle wide open, not cranking it long enough, er, needing specs????

Glad to know that the compression is about what it should be - still need to check on the heavy breathing though (oooo er!!)

Matt