Tests to ensure engine reliability

well, first off, you definatley have low compression numbers. do a compression test, and a leakdown test. you could have bent the valves a minor bit and are leaking compression around them. another posibility is your head gasket, it could be bad. basically, compression and leakdown are really the major things you should do as far as tests. you could be looking at a ring or valve job right off the bat, as well as a head gasket.

now to the turbo, there are some things you really should do. they arent mandatory but will greatly decrease the risk of blowing something once turbo'd. these are part of/on top of fixing the low compression problem.

1. Head Gasket - when going FI, you have to have a head gasket that is in good shape and that can seal very well under increased pressure. The best way to go is some kind of metal head gasket. metal head gaskets seal better than the factory paper crap. One of the more popular choices for this is the Cometic MLS (multi-layer steel) gasket. it is layers of thin still sandwiched together, then coated in viton to help it seal. they are also reinfored around each cylinder. IMO, this is a must for any type of FI. if this fixes the compression issue, then that problem is solved as well, if not then you most likely need rings or valves (or valve seals, but if you do the valves do these to while your there)

2. Head studs - this isnt hugely necessary, but for the price of ARP head studs, its worth doing to have the peace of mind. the ARP studs are stronger than stock and dont stretch as much. if you do the head gasket, you might as well do the studs. the better studs will help your nice new head gasket seal to its potential.

3. Supporting mods - I dont know where you are at as far as supporting mods, but there are a number of things you need to utilize your turbo completely that dont come in the kit. these are as follows:

a. Hi-flowing exhaust - most turbo guys on here just go with 3" pipes from teh turbo back. this keeps the spent gases moving out efficiently, and keeps everything running cooler.

b. Engine management - some cars you can just bolt up a turbo and go, but with our cars, its much better to have a way to tune your setup. this helps to maximize your setup, and keep it reliable. this is especially on our hondas because of VTEC. our iVTEC makes even it hard to tune for turbo. Pretty much, your choices in this area are HONDATA KPRO, AEM EMS, and Greddy's new V-Manage. The easiest way to go is kpro. V manage is new and i think it's cheaper but it isnt as good as kpro. and aem's ems is too expensive. GET KPRO!

c. now this is with any modded rsx, motor mounts. our stock ones are too soft and flex too much. you need at least ESMM's. they cost 25 bucks shipped from crsx store, get them. if you have alot more power than stock, go further and get complete mounts, such as innovative. trust me, without these you risk cracking that new turbo manifold of yours, or your down pipe.

there is alot more to turboing, but those are the minimums for a basic setup. either way, fix your compression issue first. pull the head and get a cometic mls gasket and arp studs. while the head is off, check your valves for nicks and dents, and bends. and your valve seals for ware. if they look good put it back together and test again. if you still have problems, its rings, and you'll need to do that before you turbo. once you do this, get mounts, and exhaust, and KPRO. bolt on the turbo, get it tuned, and rip. Oh, you'll most likely need a clutch as well. i recommend a clutchmasters ceramic (stage 3 or 4) or something like mine (clutchnet - go with the yellow PP and 6 puck disk) and a light flywheel. trust me, both of these clutches will hold w/e you can dish,. but they a SMOOTH as @#$% on the street.

Have Fun, and i hope this helped!!!

Oh, mods, maybe this should move to the turbo section, its prolly more relevant there

^^ Thank you for all that information. I already have all the turbo stuff covered as far as what kind of supporting mods I would need and everything like that. The only thing I was/and am worried about is making sure the engine is okay before going boost.

As for the compression numbers....I too thought they were very low. I read a step by step guide on CRSX on how to do a compression test and the guy who did it got numbers all in the 170's for all 4 cylinders. I'm not sure if I did something wrong during the compression test, to actually get numbers that were so low. Or if there is, in fact, something wrong with my engine.

Now what exactly does a compression test tell you? Obviously if you have low or high or average compression numbers. But for example....what do low compression numbers mean. And how would you fix them? I can tell you right now I am not a master mechanic in the least...I can do basic things (changing tires, changing oil, changing brakes, compression test) but when you start talking about ripping the motor apart and tearing the head off and checking internal parts like valves and rings.....I'm completely lost.

So do you think it would be a good idea to take my car to Acura and tell them that I have really low compression numbers and see what they can find out? And when compression numbers are as low as mine is the problem usually fixable or is it a very serious problem that can't be fixed?

Also....what is a leakdown test and what does it tell you? How do you go about doing it?

pwrdbykmfdm said:

i had low numbers on my 05 type S as well, 165 on all 4..
but somebody here told me its because i did my test with my throttle closed, and that doing a compression test with throttle closed yields lower numbers.
everywhere else i read people are getting like 200psi on all 4...
thats quite a difference. i have also misshifted a couple times.

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Okay but 165 doesn't seem TOO low. The step by step guide I saw online, the guy got all 170's. So you aren't far behind. And you say your numbers were low at 165. Look at mine....all in the 120's....so what does that say about my numbers? I can't remember if I did the compression test with the throttle pressed down or not but either way those are extremely low numbers. But my car seems to be running just fine. So that makes me wonder if it is in fact something wrong with my compression....or if I just fucked up while doing the test.

I heard that you can take your car to PepBoys and they will do a free compression test. I'm kinda nervous taking it somewhere other than Acura though because they could fuck up on a lot of things, including putting the spark plugs back in....they could over-tighten them or under-tighten them. I guess I'll just take the time to do the test again. But if I get really low numbers again....can I call Acura up and tell them and have them do a full check-up on the engine and see what they find?

i have some more info to add, this WILL help track down your issue. i spoke with some knowledgeable car guys and they said its either rings, valves, valve seals, or head gasket. here is how to determine what it is without taking shit apart. before i go further, your compression numbers are equivilent to around an 8.5:1 compression ratio, which is way low.

to determine whether it is rings or not do the following:

1. Run a compression test on each cylinder, record the numbers.

2. Take a second test, this time adding 3-4 tablespoons of oil to each cylinder prior to the test. This will help the rings seal ir they are bad.

3. Compare your findings to the first test. If your compression jumps up across all cylinders, it is DEFINATELY rings. If not, it is another issue. Because you have close numbers across the board it is prolly not the head gasket, so move on to valves and valve seals. If you still leak compression with the oil in the cylinder (across the board) it is most likely valve seals rather than valves, as if they are bad they will leak compression. Chances are your overrevs did not bend the valves, as that would be a hell of a coincidence. i thnk it would be hard to bend all the valves at once the same amount causing similar readings cross the board.

So, do the test with the oil, this should help immensly. Again, if the oil causes a jump in compression, then its rings. if it still leaks, its a valve/valve seal/head gasket issue.

Oh, and acura will do the test, but it prolly wont be as cheap as Pep Boys, but then again, you get what you pay for. (unless its under warrunty)

Good Luck

1. Yes, anything is fixable. The worst that could happen is you need a ring job, or valve job. if you do either have them do the gasket and studs then as well. the labor will prolly suck. try finding a shop that specializes in hondas. i take mine to hybrid dynamics. it is in PA by me and they do hondas. they have good prices, so find a place like that.
2. have someone else that knows what they are doing do the test.
3. the dealership wil know about the over rev if they scna your ecu. a regualr code scanner wont read the over rev code. it is a secret code only they can read. ask around to see if you can delete this somehow, im not sure but maybe try resetting the ecu. but leave it unhooked a while to make sure you clear the ecu out, like leave the battery unhooked overnight.
4. how long have you owned the car, maybe your numbers have always been bad? try the test i said with the oil. no sense worrying about something else before you do the test. i suspect its rings or valve seals, not so much you doing it wrong. get the shop manual and follow it. i have a copy on my comp if you need it i can send you it.

The only reason I am a little concerned is because I have overrevved a few times. Never mis-shifted but times when I have tried going into gear and it's popped out and I floored the gas and it took the rpm needle all the way to 9,000.

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now, if i understand this correctly, the over rev occured when in neutral. i have done this, but my tach doesnt go that high (9000). nomatter what, if you mash the gas in neutral, our ecu WILL NOT allow it to rev that high. if your tach says 9000, it is very innacurate, because the only way to rev it that high is 1) kpro 2)mechanical over rev (hitting a lower gear when upshifting). i once hit wat seemed to be 10,000 rpm according to my tach, but experts on here tell me that the tach was flat wrong and i only hit 9000 at most (i hit 2nd iunstead of 4th at 8000). i did catch it fast, but it was MECHANICAL. what your saying is not mechanical. the rev limiter will stop it from hitting that if it is throttle induced. oh and i have had no problems since then.

IF IT WASNT MECHANICAL, THEN I SERIOUSLY DOUBT YOU HIT 9000. plus our valvetrain can take 8800 stock (not for a long time though). If the computer reads overrev to the dealership, i would push the issue that you did not over rev it echanically, but instead it popped out of gear and revved out because your fot was on the gas. if that indead happened, there is an issue with your ecu's rev limiter (highly doubtful)