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Ok here go's i had my RB26 built 19000km ago. It has been running well tell last week.

Coming out of a corner i put my foot down and when i let it off the Throttle it stayed reving so i taped it a couple of times. It stop reving i pulled over car sounded like a WRX so i turned if off. Frist thought coils when i went to check this the car wouldnt start. Took it back to the shop which built the motor and they told me that the comp test was 115,120,90,5,0,80 so thats bad. Anyway what would cause this so quick.the shop blamed the head until i said they rebuilt that too. So anyway what ever is wrong with the car was not their fualt LOL.

so could be???

Fuel pump

Rings

head????

what was done to the engine in rebuild

Block was bored, decked and acid bathed

bullet rods

forged pistons

stock crank with jun collar

kings race bearings

N1 oil and water pump

gates timming belt

head has bronze value guides(exhurst side only maybe)

Anyway thats the basics so what would cause the low comp and how dose it happen so qick

Thanks Brad

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  Craved said:
i bent the exhaust side if No 6 . had 0 comp... cant see it causing a reduction of comp like the other cyclinders

That would be because some of the valves are only slighly bent.

Bent valves - only for drivers who don't like rev limiters... or for dodgy engines with weak valve springs.

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  blk180 said:
Anyway thats the basics so what would cause the low comp and how dose it happen so qick

Thanks Brad

Many things that people can only guess.

You'll have to have it properly looked at for the correct answer

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  R31Nismoid said:
Many things that people can only guess.

You'll have to have it properly looked at for the correct answer

Yer know i just wanted to see what people thought it could be. so had a fair idea how much it was going cost.

Rev limiter was set at 8200 car has stock turbos running 11psi boost tuned by a power fc 251rwkws

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Why don't you mention to them to remove the spark plugs and stick a worm camera in there to have a look, without having to remove the head.

This process have save me ten of thousand of dollars in pulling motor/heads off.

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  RPMGTR said:
My guess is that she's gobbled the rear exhaust wheel.........its a brave man that puts ceramics back onto a new engine. :)

Yer brave i think word is dum. I will pull the exhurst off tomorrow and have a look as well as check the oil. i was just at the end of my buget last time.

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