Engine: 170 HP OBDI JDM 92-95 SIR B16A (10.4:1 compression stock)

Well, after the swap from hell the engine seems to be running pretty well. I haven't been able to really accelerate at 100% because I am waiting on a new gauge cluster because the speedometer died. If the ECU doesn't get a speed signal then VTEC won't work.

Anyways, here are the readings. This was taken with an Autozone "Actron" brand tester hand tightened down into the spark plug threads. (an 11/16" socket was too big to fit in the spark plug bore to tighten the thread adapter down)

Pulley side-------------------Distributor side
150 ------- 150 ------- 165 -------- 155

The company that sold me the engine (I'm not mentioning any names yet) promised me 225 on all four cylinders. The engine is stock and runs 10.4:1 compression from the factory. These readings seem extremely low, but I haven't seen any white or blue smoke coming from the exhaust. I also haven't had any overheating problems, coolant loss, or oil consumption. I'm also beginning to think this motor was built for a turbo or something along these lines.

PS - everything on the motor's internal surfaces (valve train and crank/rods) was a nice golden oily color which makes me think the engine was well-cared for. No black carbon desposits on the external working surfaces, but I didn't pull the head to see what the combustion chambers look like.

Any suggestions or does anyone have their own numbers for this engine?

 

By the way, the measurements are in LBS. per sq. in. and here is a picture of my tester:

 

from the few i have tested:
210 210 210 208 made 141whp
175 175 173 170 made 143whp
190 190 210 190 made 138whp

 

was the engine fully warm? i got a 180 across the cyl. reading when i did it on a cold engine

 

The engine was fairly cold. I wasn't aware that this had an effect on the readings. I think I'll try a multitude of ways and record the results for all those are curious.

Thanks for the numbers eg6ajk. How did you go about testing yours to get those numbers? (hot, cold, what brand of tester, what kind of fittings) Thanks so far guys for the prompt responses.

 

mine tested

50-60-110-185

but that's after i sprayed the **** out of it!

 

A cold motor has a big effect on the compression #'s. Test it when it's hot.

 

let it run till the temperature guage is at normal..than do it

 

My B16 200 across the board, sounds the trread wasn't tight in the spark plug hole. I had the same problem testing mine......

 

when you used that tester did you do it with the car off? Or do you have the car running?

 

u cant test the compression when the car is running

 

looks fine, as long as the numbers are close to each other.

re-do the test when its warm.
did you do the test at WOT? have the gas pedal down.

 

WOT
Make sure

 

Make sure tester is good and tight and check it with motor at normal running temp. If it is still the same numbers do the following:
Remove the spark plugs and squirt a little bit of oil on top of the cylinder heads. Then do compression check. If compression improves after oil is put on top of cylinders you know it is some leaking piston rings. (the oil seals the cylinders making compression even with bad piston rings come out good) If compression is same then put crank at TDC and check and see if cam gears are also at TDC. If they are not then it is possible compression is leaking out valves.
Another thing to do is pull the intake and exhaust header and look at the valve seals. If they are really wet with oil than valetrain is bad. I know all of this because it is typical troubleshooting procedures at most shops.
Hope this helps.

Jayson S.

 

^^

 

I have the same tester.....and when I do it.....I get about 30 PSI......or 2 KPA.......why is this? How do you get these high readings?

 

Thanks Jayson,

One thing that I haven't seen any one mention is doing a valve adjustment before performing the compression check. I would imagine that if the valves have excess lash then they won't seal completely.

Here is my check list for doing a proper compression check (nearly dummy proof)
1) Make sure compression tester is tight in spark plug threads with no leaks.
2) Make sure the engine is hot while testing for compression.
3) Check for compression with the gas pedal all the way in (WOT).
4) Perform a valve adjustment to insure good valve sealing.

I'm doing the valve adjustment tonight. I am making sure that the low tolerance feeler gauge has a slight drag while the next +.001" gauge will not fit in at all. This will be my 3rd valve adjustment on a VTEC engine.

Does anyone have any tips on making sure the #2 and #3 cylinders are at TDC since you can't check the crank pulley for alignment with the pointer?

EDIT: Just wanted to let you know that the original compression numbers came from a cold engine, in need of a valve adjustment, and the throttle was closed.


[Modified by mojoGSR92, 9:57 PM 3/20/2002]