Stock compression numbers for a ka24de?

[TurbLu]

Hi guys,

I know I am suppose to warm up the engine before doing a compression test, but I cant do that right now. So what kind of compression numbers should I expect for a stock Ka24de compression?

[Indolent]

180ish, anything above is really good
and don't forget to have the throttle body open

[PS13 SILVIA]

Standard is 179 psi
Minimum is 151 psi
With max difference of 14psi

[95zilvia]

last time when i did mine cold
it was 200 psi across the board

[PS13 SILVIA]

last time when i did mine cold
it was 200 psi across the board

Possibly something wrong with the compression tester gauge or you just have a shit load of carbon biuldup on your pistons...lol

[PITCH]

Did mine last week.

190,190,195,195

97 KA24DE 128K

I'm beleiving carbon buildup also.

[gotta240]

190 or above equals

milled head
carbon buildup
bad tester
or maybe brand new ka with 15k. miles on it...doubt it though!

[95zilvia]

yeah i think ill check it again sometime

[eddie91]

i did mine today it was
175,175,188,175-_-

[Hashiriya415]

Cold rebuilt engine about 155, 180 when hot.

[91es13coop]

90 across all 4?>?? but runs really well? what am i doing wrong

[orion::S14]

^^^ Engine warm? Throttle held wide open when testing? Battery fully charged? Crank over at least 3-4 times per cylinder...

...to get a good reading.

- Brian

[terribleibs]

Did mine todau. 195 across the board. I beleive it to be rebuilt so i am assuming milled head.

[godrifttoday]

140 cold ... Fawk

[OoAtreyuloO]

18x across warm

[Silverbullet]

140 cold ... Fawk

how cold is cold? The reason you do it warm is so that it is tested at a controlled temperature where the rings will be expanded to the right amount.

Your rings will be a different size at 40 degree vs 80 degree weather affecting your compression results, it may be minimal but try again when its warm.

[MurkyRiversS13]

Can I borrow someones carbon buildup???

I got 119, 121, 120, 121 on a warm engine.

Cap full of oil gave me 140, 170, 150, 150...... new rings are in order for this bad boy.

[roboticnissan]

Ive got 90k miles on my motor and i get 150 on all four cold and 170 warm. For sure never been rebuilt all stock and original from the day it was built

[SMM]

Just for you newbs.

Warm engine up.
While engine is running pull the fuel pump fuse. ( Relieves fuel pressure)
Pull all plugs.
Disconnect distributor.
Gas pedal to the floor.
Crank 3-5 times per cylinder.


Did mine on my newest s14. 160k.

210 210 210 210.......Carbon build upppp, runs like a beast though.

[oneround1]

That's nice! ^ thanks for the info.
Compression I had was 190 across warm.

[thinhthan]

i got 150. 151. 150. 130. how much oil should i pour into the hole to check to see if i need new rings?

[fliprayzin240sx]

i got 150. 151. 150. 130. how much oil should i pour into the hole to check to see if i need new rings?

Just a oil cap full. But just looking at that 130, that shit is probably done. I'm sitting at 140-150 on mine and I'm burning oil with the HG probably on its way out.

[MurkyRiversS13]

Yup just an oil cap full of oil in each cylinder.

[thinhthan]

a oil cap as in the quart cap or a gallon cap? my car doesnt burn oil or smoke or anything. it drives fine. the engine shakes a lil though when im at like a light. so should i do a rebuild? if so is there a rebuild kit i can buy?

[MurkyRiversS13]

quart cap, definitely not the big ass cap.

Make sure you have the car turn over 7 times. remove all of the spark plugs and do one cylinder at a time withe the throttle full open. Make sure you test on a warm engine as well.

Engine shaking can be related to other things as well. Cylinder misfire and bad engine mounts. It all depends.

Im sure you can buy new rings from autozone or something if you want to do a budget rebuild. Check your cylinder walls for scoring (bad) and if you can still see the cross hatching from the honing and no scoring, you should be good with new rings.

Granted its your bottom end that is causing your low compression. Could be the head causing the problem.

[thinhthan]

do all the plugs have to be removed cause all i did was take one spark plug out put in the tester. pushed gas pedal down and cranked it like 3 time each time like 4 secs and i did it one cylinder at a time with all the other plugs in. would that make a differences if the other plugs are still in? i drove the car to the store before i checked it so it was warm. and when i put the oil in the cylinder with 130 it only raised it like prob by 5 psi so now im guessing its my lifters? that has a problem

[MurkyRiversS13]

Yea all other plugs should be out. It will make it easier for the test and better result. You unplug the injectors right?

You should do about 7 turns not 3-4. You'll hear the compression stroke when turning the car over.

[thinhthan]

how do i hear the compression stroke? and how do i know its 7 turns? i didnt unplug the injectors i just pulled out the fuel pump fuse and started it until it died than i unplug the distributor

[MurkyRiversS13]

The way you do it is the right way. When you start the test you'll be able to hear the compression stroke trust me.

[thinhthan]

and i had a question. sometimes when im doing the test ill hear a pop. is that something i should worry about?

[MurkyRiversS13]

I've never heard a pop before. Any idea where its coming from.

[thinhthan]

im sure its coming from the cylinder im testing. its random and only will pop once when im cranking. it doesnt pop every time though. it might be from the tester i hope. its hard to tell when im doing a one man job

[fliprayzin240sx]

Is the tester sealing properly? Either its not seated properly or its popping due to a faulty check valve.

I usually just let the engine do 5 compression cycle to test, doesnt really jump much after that. Just look at the needle, watch it jump and just count the cycles that way instead of trying to listen to the engine.

[thinhthan]

that sounds like a good way of knowing lol. its just hard since im doing the job by my self

[MurkyRiversS13]

Trust me...... you'll hear it just fine.

[thinhthan]

ok so my compression is low and i was planning on boosting so i decided i should do a rebuild before boosting. is there a good rebuilt kit you guys would recommend

[MurkyRiversS13]

You can just replace the rings, but I guess it all depends on what your budget is.

[thinhthan]

so if i just replaced rings i should be good for boost?

[MurkyRiversS13]

I ran 10 pounds on my stock engine with no problems. Rings gave out but I think it was more due to a tired engine.

Now I'm going forged bottom end so high boost won't be an issue. But it takes money. So far I'm 800 into the block in parts and no machine work yet lol.

[thinhthan]

even with my compressions

[MurkyRiversS13]

Well I guess it depends. When you got your results from the compression test did you do the cap full of oil and retest? If so, what were your results?

[Walperstyle]

When it comes to compression testing, its more important to have all 4 cylinders close to each other then it is to have the actual numbers higher or lower.

...usually.

If you wish to turbo the KA, I'd get a stand alone instead of doing a hack job tune with oversize injectors. That is just me. I guess its all about budget.

I originally wanted to do a 300hp KA-T, but ended up beefing up everything, now I have a $6000 project that hopefully will net me 500hp.

[MurkyRiversS13]

When I did my compression test the cylinders were all within the allowable limits of difference between cylinders, however my results were well below the service limit. So it is just as if not more important to have the right numbers.

I feel you on the goals. I started with just a T25 kit and now Im fully invested in a forged build. Youd be surprised what low compression will do to your budget lol.

[thinhthan]

i did about a cap full and it came out to 150. 150. 151. 130

[Walperstyle]

When I did my compression test the cylinders were all within the allowable limits of difference between cylinders, however my results were well below the service limit. So it is just as if not more important to have the right numbers.


Rarely do all 4 cylinders drop compression at the same time. You can fix it however you want, just saying that usually if there is problems, its usually just one cylinder.

[jam24.0s13]

How would one be able to tell if your losing compression on the rings or the valves?

[Frank_Jaeger]

How would one be able to tell if your losing compression on the rings or the valves?
Valves won't be affected by pouring in oil.