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Compression Test Bad

quick_r33

By quick_r33,
in Engines & Forced Induction

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quick_r33 Enthusiast

quick_r33

Posted
Posted

hey guys, i had noticed i had a bit of blow back so i got a compression test ( by the way i have a r33 s2) the test was

1. 130psi

2. 130psi

3. 90psi

4. 125 psi

5. 95psi

6.115psi

now i know she is on her way out but how long u think i have.. plus im entered in powercruise which is 2 weeks away..

what should i get done to improve my chances of not blowing my bottom end at powercruise ( by the way there is no way im NOT going to powercruise and there is no way im not going to give it my all so i don't want ppl saying DON'T GO)

suggestions please??

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WHITER33GTS-T Veteran

WHITER33GTS-T

Posted
Posted

Just take it out and build a 3lt when this pops. I had the same issue when powercruise was here in Tassie. I had low compression on number 6 so tried to have the engine fixed in time but missed out on powercruise.

So I say go and have some fun :(

SKiT_R31 Experienced

SKiT_R31

Posted
Posted

pfft, don't stress, it will love it :dry:

Really depends on why its down on compression, whether its the rings, or whether you've melted/warped the edge off your piston. For starters i'd disconnect your breathers and block them at the plenum/intake. (so your rockers just vent, better would be to hose and vented can them).

as long as whatever caused this in the first place (lean fuel mixes, too much timing advance/shit fuel etc) is resolved, it should survive the power cruise. Might be a bit low on power, but meh.

I melted the edge off 2 of my pistons (down to 50psi) and shattered a ring land (0psi) with 165psi on the other 3 pistons, i wound in more fuel pressure, disconnected the injector on 0psi cylinder, disconnected breathers, wound a touch of timing out of it, put the dipstick back in, topped up the oil (was sprayed all over engine bay haha) and boosted the car all the way home on 5cyl. It loved it, didn't do any more damage apart from scoring one of the cylinders, but it was probably like that anyway.

the only risk you would be taking is damaging the bits of your engine you need like scratching bores, shooting bits of shit into your turbo/sump etc. Rev it slowely up to limiter listening for rattles, if all is well, i wouldn't worry, else if you want to keep the engine to rebuild it, sit this one out.

  • 2 weeks later...
quick_r33 Enthusiast

quick_r33

Posted
  • Author
Posted

heyguys just letting u know powercruise was AWESOME! and i flogged my car to bits And she held on strong.. the only thing i had wrong was when i found myself at the back straight by myself so i clutched dropped second at 40ks and sat on the break the whole way and blew my afm pipe.. which f**ked my hose clamp.. so then everytime i boost after that the pipe just came off and i lost boost.. so i guess thats better then bringing the car home on a trailer..

GTScotT Grand Master

GTScotT

Posted
Posted

my engine compression is 140 140 140 140 0 15, then add some oil to the bores and its all like 160 160 160 160 0 160

i have a big problem, yet ive been giving this motor hell for almost a year now and its kept going

quick_r33 Enthusiast

quick_r33

Posted
  • Author
Posted
my engine compression is 140 140 140 140 0 15, then add some oil to the bores and its all like 160 160 160 160 0 160

i have a big problem, yet ive been giving this motor hell for almost a year now and its kept going

hahaha nice work.. yeah they hold on pretty strong.. like last yr at powercruise i ran my STOCK trubo at 15psi.. so alot for a stocko and yeah i still have the turbo today and is great..has no shaft play or anything.. ( its not on my car anymore tho)

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