probably a 'stupid' question - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

XxRomeSDSxX · 07-20-2011, 02:46 PM

im looking to get myself a 2003 350z but the owner said that it blows blue smoke. Now in most cars that usually means that oil got under the piston rings and is burning(correct me if im wrong). Now my question is should i avoid this car all together or miss out on a killer deal? If i do get the car is it more cost effective to bore the cyl's out and swap them with forged pistons ect. or just swap it out for a new motor? I am new to these cars and all advice is welcome. Thanks! and if you can give me an idea of what each option would cost thatd help me out a lot as i am on a budget

theboy · 07-20-2011, 02:54 PM

depends on how good the deal is. Could be rings, or it could be valve seals. I wouldnt bore it out if you dont have to. Unless your looking to make a bunch of power and not use it as a daily. Machine work is big money an dpistons arent cheap either. But your looking at a full rebuild which will give you a brand new motor once your done.

XxRomeSDSxX · 07-20-2011, 03:02 PM

it has 131k on the clock and he wants 7k for it. my power goal is 300-350whp to start and ill go from there. but im talking in the long run.

JIMB0 · 07-21-2011, 08:14 AM

i would pass. thats too many miles for a Z. What are your plans and price range? FI or NA?

theboy · 07-21-2011, 08:24 AM

your descion will be made once you figure out what you want to do with the car. Is it going to be a daily driver immediately? Or are you looking for a long term project? It sounds like you could drive it for a little while, but your going to have to rebuild it eventually. So you might as well get everything to do so. Then park it and rebuild it. But if your not looking for a long term project, then id pass. Its going to need a full rebuild to figure out whats actually worn out. By that time youll have a butthole load of time and money wrapped up in it that you could have found a better condition z for.

But its not my money, so im not going to tell you what to do with it. If your set on it then do what you want. Time to be a big boy and make your own descions. Not have a bunch of random strangers miles and miles away tell you what they think about it.

jr_ss · 07-21-2011, 10:04 AM

The earlier VQs had oil consumption problems from the beginning. I'm sure now with higher miles it, it only accentuates that existing condition...

shadowhunter66 · 07-21-2011, 10:37 AM

Granted that's a lot of miles, but Z's are built to last 200k+ miles if you treat them right. If your unsure, ask if you can have a mechanic check it out. If they say no, then walk away. But really it's up to you

XxRomeSDSxX · 07-21-2011, 11:29 AM

I want this to be my daily ASAP. I will be doing most of the work myself i.e. pulling the motor. my power goal is 300-350whp, so going NA vs. FI really depends on which one gets me there the easiest. but the question still remains what is more cost effective? to just swap the motor out with a used one, or rebuild the stock motor? so as an example:

if its roughly $3k for the new motor vs. $8k-10K for all the internals id rather just swap the motor out and spend the change on performance.

but if its like $3k for the new motor vs. $3,500 for all the built internals minus the machining ill just spend the extra $500 and have a fresh motor.

and then my other question is if i do swap the motor, will i have problems with that anti-theft system or getting my original wiring harness to work on the swapped motor?

idk if this really makes sense or not, if you need me to explain more just let me know.

rcdad123 · 07-21-2011, 11:52 AM

if your gonna do the work, i say rebuild the existing engine. buying a used one is not always a good idea, especially the vq35 because of the oil consumption problem from the factory. you can get away with honing the cylinders and reusing the pistons. rebuild both cylinder heads(valve job, resurface, replace valve seals, and thorough cleaning), polish the crank if you need to,( not always needed), and replacing all the seals and gaskets, piston rings(hopefully a revised oem from the factory), water pump, clutch if it`s a stick shift, thermostat, and installing headers before you put the engine back in(makes it a lot easier), timing chain guides and tensioner, and check the oil pump. if it`s still good, re use it. that would probably set you back close to 3k, but at least it`s almost brand new and you know it would work with whatever you had before you took it out. good luck.

XxRomeSDSxX · 07-22-2011, 07:16 AM

thats exactly what i was looking for! thanks!

07-20-2011, 02:46 PM	#1
XxRomeSDSxX Join Date: Jul 2011 Location: CT Age: 28 Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	probably a 'stupid' question im looking to get myself a 2003 350z but the owner said that it blows blue smoke. Now in most cars that usually means that oil got under the piston rings and is burning(correct me if im wrong). Now my question is should i avoid this car all together or miss out on a killer deal? If i do get the car is it more cost effective to bore the cyl's out and swap them with forged pistons ect. or just swap it out for a new motor? I am new to these cars and all advice is welcome. Thanks! and if you can give me an idea of what each option would cost thatd help me out a lot as i am on a budget

07-21-2011, 10:04 AM	#6
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,056 Trader Rating: (34) Feedback Score: 34 reviews	The earlier VQs had oil consumption problems from the beginning. I'm sure now with higher miles it, it only accentuates that existing condition... __________________ My SR20VET

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07-20-2011, 02:54 PM	#2
theboy Zilvia Addict Join Date: Apr 2010 Location: Chicago Age: 32 Posts: 618 Trader Rating: (10) Feedback Score: 10 reviews	depends on how good the deal is. Could be rings, or it could be valve seals. I wouldnt bore it out if you dont have to. Unless your looking to make a bunch of power and not use it as a daily. Machine work is big money an dpistons arent cheap either. But your looking at a full rebuild which will give you a brand new motor once your done.

07-20-2011, 03:02 PM	#3
XxRomeSDSxX Join Date: Jul 2011 Location: CT Age: 28 Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	it has 131k on the clock and he wants 7k for it. my power goal is 300-350whp to start and ill go from there. but im talking in the long run.

07-21-2011, 08:14 AM	#4
JIMB0 Zilvia FREAK! Join Date: Jul 2011 Location: Texas Posts: 1,002 Trader Rating: (22) Feedback Score: 22 reviews	i would pass. thats too many miles for a Z. What are your plans and price range? FI or NA?

07-21-2011, 08:24 AM	#5
theboy Zilvia Addict Join Date: Apr 2010 Location: Chicago Age: 32 Posts: 618 Trader Rating: (10) Feedback Score: 10 reviews	your descion will be made once you figure out what you want to do with the car. Is it going to be a daily driver immediately? Or are you looking for a long term project? It sounds like you could drive it for a little while, but your going to have to rebuild it eventually. So you might as well get everything to do so. Then park it and rebuild it. But if your not looking for a long term project, then id pass. Its going to need a full rebuild to figure out whats actually worn out. By that time youll have a butthole load of time and money wrapped up in it that you could have found a better condition z for. But its not my money, so im not going to tell you what to do with it. If your set on it then do what you want. Time to be a big boy and make your own descions. Not have a bunch of random strangers miles and miles away tell you what they think about it.

07-21-2011, 10:37 AM	#7
shadowhunter66 Leaky Injector Join Date: Sep 2008 Location: West LA Posts: 55 Trader Rating: (1) Feedback Score: 1 reviews	Granted that's a lot of miles, but Z's are built to last 200k+ miles if you treat them right. If your unsure, ask if you can have a mechanic check it out. If they say no, then walk away. But really it's up to you

07-21-2011, 11:29 AM	#8
XxRomeSDSxX Join Date: Jul 2011 Location: CT Age: 28 Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	I want this to be my daily ASAP. I will be doing most of the work myself i.e. pulling the motor. my power goal is 300-350whp, so going NA vs. FI really depends on which one gets me there the easiest. but the question still remains what is more cost effective? to just swap the motor out with a used one, or rebuild the stock motor? so as an example: if its roughly $3k for the new motor vs. $8k-10K for all the internals id rather just swap the motor out and spend the change on performance. but if its like $3k for the new motor vs. $3,500 for all the built internals minus the machining ill just spend the extra $500 and have a fresh motor. and then my other question is if i do swap the motor, will i have problems with that anti-theft system or getting my original wiring harness to work on the swapped motor? idk if this really makes sense or not, if you need me to explain more just let me know.

07-21-2011, 11:52 AM	#9
rcdad123 Zilvia Addict Join Date: Jul 2011 Location: san diego Posts: 639 Trader Rating: (0) Feedback Score: 0 reviews	if your gonna do the work, i say rebuild the existing engine. buying a used one is not always a good idea, especially the vq35 because of the oil consumption problem from the factory. you can get away with honing the cylinders and reusing the pistons. rebuild both cylinder heads(valve job, resurface, replace valve seals, and thorough cleaning), polish the crank if you need to,( not always needed), and replacing all the seals and gaskets, piston rings(hopefully a revised oem from the factory), water pump, clutch if it`s a stick shift, thermostat, and installing headers before you put the engine back in(makes it a lot easier), timing chain guides and tensioner, and check the oil pump. if it`s still good, re use it. that would probably set you back close to 3k, but at least it`s almost brand new and you know it would work with whatever you had before you took it out. good luck.

07-22-2011, 07:16 AM	#10
XxRomeSDSxX Join Date: Jul 2011 Location: CT Age: 28 Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	thats exactly what i was looking for! thanks!