So i picked up an sr20det s13.5 in good shape but engine was bad. Something happened to the valvetrain that caused it break 2 rocker arms on the exhaust side and broken cam and broken timing tensioner. The pistons got stamped by the valves but mostly scaring. The cylinder walls were not damaged at all. So i am sourcing a new head to replace my broken one. I'll post up pics of the pistons.
my question is if the pistons aren't poked through by the valve stems would you guys replace them and if so would you go oem or aftermarket bullet proof.
I have an rb25det sitting in my garage so i'm wondering what to do?
My dilema
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USMCgetsome
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rc1honda
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Re: My dilema (USMCgetsome)
Well thats kinda of a tough one. I had a similar porblme with my SR. I reversed the position of the rocker guides and the valve shims and threw all my rocker on my intake side.
Dropped a vale and it hit the piston. I kinda smoothed the piston out and had no damage to the cyclinder walls. I fixed the head put it back together and did a leak down. It still had pefect leakdown and compression and runs great.
Now the damage was pretty minimal, and i turned the car off as soon as heard a grind. But if the piston tops are a litte beat up it's no big deal. But try to smooth them out . You don't want high spots the will get real hot and melt. You want to have smooth combustion.
Also if your going to rebuild just go bulletproof. A OEM rebuild is not much cheaper then a Manley rod, Oliver piston combo.
Or i would just put the RB25 in and call it a day. Sell what you can off the SR and buy some goodies for the RB. Big turbo and EMS would be nice. Get the mounts and wire it up. Then you will have a very nice RB s13.5
Dropped a vale and it hit the piston. I kinda smoothed the piston out and had no damage to the cyclinder walls. I fixed the head put it back together and did a leak down. It still had pefect leakdown and compression and runs great.
Now the damage was pretty minimal, and i turned the car off as soon as heard a grind. But if the piston tops are a litte beat up it's no big deal. But try to smooth them out . You don't want high spots the will get real hot and melt. You want to have smooth combustion.
Also if your going to rebuild just go bulletproof. A OEM rebuild is not much cheaper then a Manley rod, Oliver piston combo.
Or i would just put the RB25 in and call it a day. Sell what you can off the SR and buy some goodies for the RB. Big turbo and EMS would be nice. Get the mounts and wire it up. Then you will have a very nice RB s13.5
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USMCgetsome
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Re: My dilema (rc1honda)
man i totally agree with you about smoothing it out. I check to see if i had pierced a piston head. I haven't found any more damage than some good scaring. Now on to the good stuff what did you use for the smooth down process:
files, sand paper, scotch brite pads?
files, sand paper, scotch brite pads?
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Hijacker
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If there was contact with the piston, the piston needs to be changed. The contact will cause metal fatigue and the piston will fail eventually. A lot of times during piston and valve contact, people don't realize that the piston is damaged even if it shows no signs of contact. But I always say it's better to be safe than sorry. If you have the motor open, there's no reason not to replace the parts as it's a pain in the butt to have to reopen it again anyways.