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low compression on a rebuild

To: british-cars@hoosier
Subject: low compression on a rebuild
From: Dennis Wilson <DWILSON@OREGON.UOREGON.EDU>
Date: Sun, 26 Apr 1992 17:14 PDT
Whats the answer?  :

3K miles ago I freshened up the 1300 spit motor in my "should be a 1500" 
midget.I took the block, pistons, and crank to British Automotive here in 
Eugene to 
have them look and see if I needed a rebore and regrind.  No they said, all are
fine, the crank has been ground 20 thou under already.  So I put it all back 
together with new bearings and rings but same pistons.  After I had run it in,
I was not impressed with the performance.  I had larger inlet valves, an SK 
carb, a kent cam, tubular exhaust manifold. but it appeared to drive just as 
before.It has been stored for most of the winter and I deceided to drive it 
yesterday.

I was curious if the compression was OK.  SHOCK, HORROR.

Dry test= 110  +/- 3lbs on all four cylinders.
Wet test= 185  =/- 4lbs on all four cylinders.

I was maticulous when I put it together and during the break-in period.
Could it be Brit Auto screwed up??  I wonder if honing the bores and bead 
blasting the pistons would cause this.
Also 15K before the rebuild compression was 145lbs.
Anyway I'm pissed off now!!

After a rebore and new pistons would a dry comp test be anywhere as high as a 
wet test???

Cheers DW


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