Im considering rebuilding the engine, but I dont want to have to go through the trouble of redoing the bottom end. I dont want to touch the bearings. dont have tools/knowledge to do it either. I was thinking that I could just keep the block, or bore it .020 over and just change out the pistons(forged) and rings. would this suffice, or would it be pointless to do.
Steve
what is the least I can get away with: rebuild?
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Structure240sx
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- Joined: Sun Oct 06, 2002 5:04 pm
if you will be getting it bored then the bearings will be coming out anyway. the pistons are part of the bottom end. new or forged pistons would be perfect for you and not cost too much. not sure on what year the sohc had lower compression, but if you have the year with higher compression then maybe you could get the stock lower compression pistons to help out some against detonation. plus they would be cheap
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Checkered-Member
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- Car: 1998 Nissan Altima (modded)
2003 Audi A6 2.7T (stock) - Contact:
the stock rods are pretty beefy, most people here agree that you can keep them (if they're in good shape) and still boost pretty safely. If you're replacing the pistons though and boring the engine, structure is right: you might as well do the bearings as well.
You dont need to worry too much about not knowing all the tools/how to assemble a bottom end and all that. If you want, the machine shop you have bore your block + fit your pistons and rings (Im sure the rings will have to be file fit) can assemble the bottom end for you and balance it all. That's what I'm doing-- I'm not about to take it on myself to learn how to assemble + balance an engine correctly on the very first try.. It's not too expensive to have the pros put it together, so you might as well..
good luck man!
You dont need to worry too much about not knowing all the tools/how to assemble a bottom end and all that. If you want, the machine shop you have bore your block + fit your pistons and rings (Im sure the rings will have to be file fit) can assemble the bottom end for you and balance it all. That's what I'm doing-- I'm not about to take it on myself to learn how to assemble + balance an engine correctly on the very first try.. It's not too expensive to have the pros put it together, so you might as well..
good luck man!
I put my motor together myself, in fact I'm just finishing up.in retrospect, whatever the machine shop charges would have been well worth it. Its not so much that there were things that I did that you couldn't do, its just that its a pain in the *** to measure all those clearances and all that ****, and it takes special tools (ring filer, piston compressor, etc) and such...
You really dont want to try to risk putting amotor together when you are on a budget. Its a risk due to your inexperience. Id hate to spend all that money only to tear it up form me not knowing how to assemble it.
-Josh
p.s.--machine shops not only kmow how ot assemble them, they can use tricks to lengten the lifespan depepnding on app, and/or make more power. Things like proper ring gap, and bearing clearance, etc.Also--they can do cool stuff like shim the oil pump while they assemble the motor to give more oil pressure. etc..
-josh
-Josh
p.s.--machine shops not only kmow how ot assemble them, they can use tricks to lengten the lifespan depepnding on app, and/or make more power. Things like proper ring gap, and bearing clearance, etc.Also--they can do cool stuff like shim the oil pump while they assemble the motor to give more oil pressure. etc..
-josh
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Structure240sx
- Posts: 5615
- Joined: Sun Oct 06, 2002 5:04 pm
Checkered-Member wrote:If you want to run more boost, I would invest the money in fuel management rather then just lower compression pistons. If your motor is in good condition (a compression check will verify that) then there is no need to do anything to it.
he has done a compression test and found the results to be very low. he needs a rebuild anyway so the lower compression might be a good idea while doing something like that.