Hey everyone, im new to the boards, and fairly new to hondas. im more of a Nissan guy. anyway i just bought a 93 civic coupe with a b16 with bolt ons. the guy i bought the car from said the engine had been rebuilt with higher compression pistons installed, raising the compression to 11:1. i wasnt sure if the engine had really been rebuilt so i did the compression check to find the condition of the engine.

the results were 250PSI across all 4 cylinders. now, i dont know if this is normal for this engine or not, but from my experiances with most stock engines i have had readings in the 150psi range. from the results of this, i think it actualy does hace higher compression.

now what im wondering is -

is there any way to increase the compression of this engine without replacing the pistons with aftermarket forged ones? im thinking possible type r pistons, different crank, milled head, ect.

anyone know of any way to see if the engine has been rebuilt, or has different internals without doing a teardown of the engine?

and finaly, with the higher compression ratio, how safe would it be to run nitrous on the engine. im thinking about installing a 50 or 75 shot to it.

mods to engine- dc headers, injen short ram intake, MSD coil, AEM adjustable cam gears, and some sort of MSD ignition box.

 

You want them to all be within like 5% or something oe eachother, if they are the same across the board, it looks good.

 

you could get a thin headgasket or high compression flat valves i wouldnt reccoment running nitrous on a high compression motor without a bottom end build up... its risky enough on stock compression. ittl work but your motor will be toast alot sooner than it should be

 

so is this a normal compression test reading? i know the cylinders should be the same.

also with a properly tuned and installed nitrous setup (safe shot size) i think it should be reliable and safe to run.

 

Great numbers! I love healthy, high cr engines

 

::cue Hybrid93EG::

Disconnect the injector plugs
Disconnect the plug(s) leading to the dist
Put in the gauge, get in the car
Push the gas pedal ALL the way down
Crank the car no more then 6 times over
Repeat

Thats the proper way.
It should be a warm engine.
Compression for a stock b16 should be around 210-215 (10.4:1)
Search around theres a lot of good info on compression and interpreting their results.

All in all it sounds like the motor is healthy Numbers like that are not uncommon in the N/A honda world.
Eric

 

 

I have ctr pistons and 250 is what I have across the board

 

good healthy results.

 

street EG i know how to do a compression test, but thanks for the review.

what i didnt know was if these results were normal or not.

evade this honda - do you have the ctr pistons in a b16? whats does that make the c/r?

 

yes they are in a b16. That made the compression 11.1 and the test came out to 250 across the board. with hondata, stage1 cams with the ctr pistons makes about 180 hp and 115 trq