Compression Test

[Adnic69 0]

I did a compression test lastnight on the car, just to check things really.

I got the following readings

 

1) 12.5

2) 12

3) 13.4

4) 14

all readings were in bar.

 

Is this good, bad?

From this how can you work out the compression ratio?

If it helps engine spec is below and was rebuilt roughly 10,000 miles ago.

[hengti 2]

that's a variation of between 175 and 200psi (bar x 14.5 to convert to psi)

 

i'm no expert, but would have thought that they should be closer on a rebuilt engine - ?

[ALEX 98 1 Cars]

Did you remember to hold the throttle open during the test?

[greig 0]

can you get a compression test kit from halfrauds etc? are they any good?

 

Greig

[Livelee 0]

can you get a compression test kit from halfrauds etc? are they any good?

 

Greig

 

I got mine from Halfords recently £18.99

 

I got between 155psi and 180psi on my mi16. Engine hot and throttle open.

[Adnic69 0]

I did not hold the throttle open no.

[ALEX 98 1 Cars]

Yeah I always forget to do that too.

You get slightly higher readings if you open the throttle

[welshpug 1,657]

yup, throttle open, you get a vacuum if you dont hold it open and you get lower and inconsistent readings.

 

and for others looking for compression testers theres a selection here from under £8!!!

 

http://www.pvrdirect.co.uk/products.aspx?i...r3=Gauged+Tools

[PumaRacing 2]

http://www.pumaracing.co.uk/comp.htm