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low compression on a bult 2.3L

ERJ-145 driver

Proven Member
Jul 16, 2015
Oceanside, California
Hello everyone.

Im back into DSM game and i recently bought my friends 2.3L 2G. I wanted to get it tuned on E85 so I started doing a little maintenance on it. The Warm Compression test was cyl1. 130 cyl2 128, cyl3 130, cyl 4 130. the Motor has about 3K on the build. The car does smoke only some times after boost. And if so its a small puff. Here is a list of mods. I hope someone can point me in the right direction. thanks

The list:

2.3L Stroker:
Eagle rods
Wiseco Pistons .020
OEM 4G64 Crank

2G Head:
1mm oversized Supertech Valves I/E
Supertech Dual Valve Springs
3g Lifters
Bronze Valve Guides
Titanium Retainers
5-Angle valve job
Ported and Polished Head
GSC S2 Cams

HeadsUp Panda

Proven Member
Oct 27, 2015
Somerset, Kentucky
You can always check your lifters to make sure none are stuck. If so they can hold the valves open a bit and show low compression. I doubt this though, so I will second gobblin and recommend doing a leak down test.


Proven Member
Jan 26, 2013
yuma, Arizona
squirt a little oil in the chambers through the spark plug holes and check to see if the compression comes up. That's a quick easy way to check the rings.

ERJ-145 driver

Proven Member
Jul 16, 2015
Oceanside, California
Thanks for the feed back guys, I went and bought another compression tester since the one used was a few years old. The new numbers are:
Cyl1-180, Cyl2-175, Cyl3-185, Cyl4-180

I'm still going to do the leak down test and make sure that's ok before going out and tuning on E85.
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