Compression Test

Author
Discussion

Heliox

Original Poster:

450 posts

262 months

Thursday 8th April 2004
quotequote all
Can anyone tell me what compression readings I should be getting for my 4.3 V8 Griff as im about to put some new plugs in and thought i'd do a compression test at the same time.

many thanks

h

Boosted LS1

21,187 posts

260 months

Thursday 8th April 2004
quotequote all
Hi Helioux,

I had a low compression engine done at 160 odd so I'd expect anything over that to be a bonus. Maybe 180-190 might be about right?

steve_D

13,746 posts

258 months

Friday 9th April 2004
quotequote all
The actual figure is not to important. Having them all read about the same is what you are looking for.
A worn engine will have one or more cylinders with poor readings while the remaining good cylinders are trying to keep the ship afloat.
Steve

wedg1e

26,801 posts

265 months

Friday 9th April 2004
quotequote all
I did a comp. test on the Esprit the other week. I sh@t myself when no.3 read 40 psi lower than the other 3 cylinders. Turned out the gauge wasn't quite screwed in tight enough... hew:

<pause>

Just dug out the figures from the last compression test I did on the TVR: either side of 170 psi. That's a 3948 running abut 9.25:1 c.r., with less than 5000 miles on the pistons and bores.


Ian

Heliox

Original Poster:

450 posts

262 months

Friday 9th April 2004
quotequote all
Ok ,thank you for the info.

h

will make sure its screwed in properly

chris_n

1,232 posts

258 months

Friday 9th April 2004
quotequote all
Maybe stating the obvious, but make sure the engine has been warmed up as well.