Solo
[14] Master
Lol... I can't say much in a thread like this. I know facts about cars but not too much on how to fix them. I wish I knew how to fix cars better.
Stupid mechanics thread
- Thread starter damn-I-Suck
- Start date
Hot Rod Dave
"Saucy saucy minx"
Trust me, no you dont.
Solo
[14] Master
I just want to learn some basic things so I can maintain my truck better. I can do most of the stuff myself but I need to learn a few more basic things. Plus, about the idiots that don't know anything coming up like they know everything; I get that a lot with computer related ordeals. People thinking they can run games on their $300 laptop... Don't get me started man, I don't want to derail this thread. :P
Hot Rod Dave
"Saucy saucy minx"
Dispite your ugliness. You can always come to me if you help. Anytime
Pernicious-Soul
[10] Knight
Kinda on topic here so does anybody have an knowledge on turbos?
Hot Rod Dave
"Saucy saucy minx"
Yeah turbos take exhaust air and force it back into the engine.
hahahaha
what specifically are you talkin?
Pernicious-Soul
[10] Knight
I'm considering turboing my 04 spec v and was curious about the effects of it on a NA bone stock engine. Will it affect the reliability of car, gas mileage etc.
Hot Rod Dave
"Saucy saucy minx"
Ummmm
Yes
Yes and
Yes
Im a little slammed at work at the moment. Im not ignoring you I swear. Ill elaborate later when I get home
Hot Rod Dave
"Saucy saucy minx"
Ok so i finally got home and can put this post in a way that will be on topic...
Lemme explain why just slapping on a turbo is a "stupid mechanic" move.
Speaking in a general engine sense, when engines are made, of course aspiration is in the formula. So motors that are supercharged, turbo'd, injected, carbureted etc, are all built differently internally in consideration of their respected aspirations. A naturally aspirated engine needs higher compression to achieve the ultimate performance. As to where a supercharged or turbo'd engine needs to have lower compression to compensate for the enormous amount of air being suck through the intake.
Horsepower is measured in laymens terms, by how much air and fuel you can suck into the engine, process those elements, and get them out of the motor. Or more technically called CFM. So thus the more air and fuel you can force into the motor, burn it, use it, and get it out of the engine, the more power you will make.
So being that the internet is full of theories of engine performance, and those mechanics that know just enough about cars to get them in trouble, realize that if they slap a turbo on their engine, they are going to make monster power. This is true to a point, but most of the time hinders the engine or worse causing major engine failure. And here is why...
Going back to the beginning of my lesson, remember when i said all motors are built considering aspiration? Well here is what happens. You take a nissan SE-R that has roughly 175hp and 190 lbs of compression. Just by bolting on a turbo (which is a lot harder than just bolt things on to work right) you drastically increase the compression (or in laymens terms air) into the engine. Boosting compression up to lets say 225hp and now 13:1 or 225lbs of compression. Well to properly get every advantage of the turbo you just put on, well now you need more fuel to use that air, to use that extra fuel you need more spark to burn all that extra fuel.
But wait, it gets better...
The pistons that came with the engine aren't not only not strong enough, but the compression is now way to high and you are at HUGE risk on throwing a connecting rod out the side of the block. We need to get better stronger pistons to hold this thing together. The cylinder head is now trying to push through all that new amounts of fuel and air. So your actually choking your motor and it cant process all that air and fuel (or CFM) thus making less power than you should be making. I could go on and on about the domino effect doing something that stupid really does, but im hoping you get the idea.
If you want to play with that SE-R, have a plan. What do you use the car for? Racing? Cruising? To and from work? Daily driver, weekend drag racer? Whatever. And make an engine around that.
Im guessing you use the car as a daily driver. So ripping the engine apart and spending $1000's is prolly not what you want. But at the same time, you want a little "pep in your step". You don't want to sacrifice reliability for performance. But there are some things you can do.
Start with exhaust. A nice header and cat back system (preferably one that isn't totally obnoxious sounding) will do a lot for you. I don't mean some fancy muffler with a coffee can tip. Im taking headers nice pipes that open it up high flow cats and some mean sounding muffler.
Next start with suspension. Lower it. Get the alignment right. Give it some negative camber and toe it in 1/8 of an inch in the front (google it if you don't understand) get that car to act right for you. You be surprised how much fun it makes a car to drive when it handles good.
Then get into engine stuff. Most horsepower of any performance engine, is in the cylinder head. Look into porting and polishing. .5mm oversize valves, titanium retainers and springs and some lumpy cams. Doing this will require some fuel injector, intake (air and fuel), and ignition work.
Then there will come a day when you are ready to make the nissan a full on race car and we can start playing with turbos and stuff. Well you will have the foundation already to get every piece of horsepower out of what you are doing.
I cant tell you how many morons start by building a car backwards. Specially cars they need to drive everyday. Spend a fuck ton of money on parts only to have blown up their engine the second they start it. Starting by messing with aspiration without considering what comes with that, is just completely bone headed. Think of it this way, you cant put a ferrari engine, in a geo metro with out some kind of major modification. So start with a plan. Build your car around your plan starting with the foundation. Get the frame of the car ready for the engine you want to build. Make sure when you add all that power and speed, that your car can handle going 140mph and breaking to 0 in 100ft. Make sure if you're gonna make a left turn at 100mph, that your car will do that without taking out and old lady and a telephone pole. Then get your motor right.
Lemme explain why just slapping on a turbo is a "stupid mechanic" move.
Speaking in a general engine sense, when engines are made, of course aspiration is in the formula. So motors that are supercharged, turbo'd, injected, carbureted etc, are all built differently internally in consideration of their respected aspirations. A naturally aspirated engine needs higher compression to achieve the ultimate performance. As to where a supercharged or turbo'd engine needs to have lower compression to compensate for the enormous amount of air being suck through the intake.
Horsepower is measured in laymens terms, by how much air and fuel you can suck into the engine, process those elements, and get them out of the motor. Or more technically called CFM. So thus the more air and fuel you can force into the motor, burn it, use it, and get it out of the engine, the more power you will make.
So being that the internet is full of theories of engine performance, and those mechanics that know just enough about cars to get them in trouble, realize that if they slap a turbo on their engine, they are going to make monster power. This is true to a point, but most of the time hinders the engine or worse causing major engine failure. And here is why...
Going back to the beginning of my lesson, remember when i said all motors are built considering aspiration? Well here is what happens. You take a nissan SE-R that has roughly 175hp and 190 lbs of compression. Just by bolting on a turbo (which is a lot harder than just bolt things on to work right) you drastically increase the compression (or in laymens terms air) into the engine. Boosting compression up to lets say 225hp and now 13:1 or 225lbs of compression. Well to properly get every advantage of the turbo you just put on, well now you need more fuel to use that air, to use that extra fuel you need more spark to burn all that extra fuel.
But wait, it gets better...
The pistons that came with the engine aren't not only not strong enough, but the compression is now way to high and you are at HUGE risk on throwing a connecting rod out the side of the block. We need to get better stronger pistons to hold this thing together. The cylinder head is now trying to push through all that new amounts of fuel and air. So your actually choking your motor and it cant process all that air and fuel (or CFM) thus making less power than you should be making. I could go on and on about the domino effect doing something that stupid really does, but im hoping you get the idea.
If you want to play with that SE-R, have a plan. What do you use the car for? Racing? Cruising? To and from work? Daily driver, weekend drag racer? Whatever. And make an engine around that.
Im guessing you use the car as a daily driver. So ripping the engine apart and spending $1000's is prolly not what you want. But at the same time, you want a little "pep in your step". You don't want to sacrifice reliability for performance. But there are some things you can do.
Start with exhaust. A nice header and cat back system (preferably one that isn't totally obnoxious sounding) will do a lot for you. I don't mean some fancy muffler with a coffee can tip. Im taking headers nice pipes that open it up high flow cats and some mean sounding muffler.
Next start with suspension. Lower it. Get the alignment right. Give it some negative camber and toe it in 1/8 of an inch in the front (google it if you don't understand) get that car to act right for you. You be surprised how much fun it makes a car to drive when it handles good.
Then get into engine stuff. Most horsepower of any performance engine, is in the cylinder head. Look into porting and polishing. .5mm oversize valves, titanium retainers and springs and some lumpy cams. Doing this will require some fuel injector, intake (air and fuel), and ignition work.
Then there will come a day when you are ready to make the nissan a full on race car and we can start playing with turbos and stuff. Well you will have the foundation already to get every piece of horsepower out of what you are doing.
I cant tell you how many morons start by building a car backwards. Specially cars they need to drive everyday. Spend a fuck ton of money on parts only to have blown up their engine the second they start it. Starting by messing with aspiration without considering what comes with that, is just completely bone headed. Think of it this way, you cant put a ferrari engine, in a geo metro with out some kind of major modification. So start with a plan. Build your car around your plan starting with the foundation. Get the frame of the car ready for the engine you want to build. Make sure when you add all that power and speed, that your car can handle going 140mph and breaking to 0 in 100ft. Make sure if you're gonna make a left turn at 100mph, that your car will do that without taking out and old lady and a telephone pole. Then get your motor right.
Pernicious-Soul
[10] Knight
Thanks for a very informative post hard. Yes its my daily driver so reliability is first and foremost and I've already did exhaust w/ nice nismo cat back. Just purchased a stillen header and installing tomorrow.
Only reason I'm considering a turbo is I found a extremely good deal on a nice threadstone turbo. With it being such a good deal I prolly buy it and do alittle research into what components need upgraded to support the turbo. Then maybe I attempt the install.
Speaking of p&p of head and plenum do you do that at your shop? If so I might can send some business your way.
Only reason I'm considering a turbo is I found a extremely good deal on a nice threadstone turbo. With it being such a good deal I prolly buy it and do alittle research into what components need upgraded to support the turbo. Then maybe I attempt the install.
Speaking of p&p of head and plenum do you do that at your shop? If so I might can send some business your way.
FleshMasher
[13] Hero
Got no clue about mechanic, but during my school time i had a traineeship at a Ford authorized repair shop.
There two mechanics were messing with each other, one had a motor open, when he was away for breakfast or something, the other poured coke in the cylinders of that open engine as some kind of prank.
Looked like a stupid mechanic thing to do for me, but the coke pouring mechanic said coke in the cylinder is no problem. The other mechanic probably cleaned it up later, but still...
Or is that some dick move to ensure that the customer has to come back?
There two mechanics were messing with each other, one had a motor open, when he was away for breakfast or something, the other poured coke in the cylinders of that open engine as some kind of prank.
Looked like a stupid mechanic thing to do for me, but the coke pouring mechanic said coke in the cylinder is no problem. The other mechanic probably cleaned it up later, but still...
Or is that some dick move to ensure that the customer has to come back?
Hot Rod Dave
"Saucy saucy minx"
Pooring coke in the chlinder will make it look like the bores are glazed up. Gives it a sticky and gooey apprearence is all. Doesnt really hurt it. The car will just sputter and smoke for a minute when started till it burns away. Not a big deal. Seen that before LOL.
I dont do port and polish at my shop. Any moron can grad a die grinder and start hack away at the ports, but smart mofos know that you need a flow bench to see what you are doing and make sure things flow evenly and correctly in each cylinder. Ive had to fix many hack jobs over the years.
A decent basic port and polish by a good machine shop should cost around $300-$400. That should also not include the price of the valve job to put the head back together. Dont let your buddy that says he knows how to do it hack up your head in his garage. Have it professionally done by a good performance machine shop.
Now off to see how much flow benches are. Ive always wanted one. Hahaha
I dont do port and polish at my shop. Any moron can grad a die grinder and start hack away at the ports, but smart mofos know that you need a flow bench to see what you are doing and make sure things flow evenly and correctly in each cylinder. Ive had to fix many hack jobs over the years.
A decent basic port and polish by a good machine shop should cost around $300-$400. That should also not include the price of the valve job to put the head back together. Dont let your buddy that says he knows how to do it hack up your head in his garage. Have it professionally done by a good performance machine shop.
Now off to see how much flow benches are. Ive always wanted one. Hahaha
TsunamiBye
[14] Master
I have a question since I hardly know much about cars. What is a boxer engine and how does it work? Right now, I'm gonna take notes since I'm interested in working for Subaru. Pretty steep dream from where I stand, but I want to start somewhere since I'm interested in anything that has a boxer engine.
Hot Rod Dave
"Saucy saucy minx"
A boxer engine refers to not only subaru engines, but any engine that has the heads mounted directly to the sides of the block as opposed to on top.
Subaru, air cooled VW, chevy corvair all have the same type of engine. Just refers to the engine style is all. I used to have a GIF on a subaru engine that totally explains why its called a boxer. If you were to watch the pistons up in and out, it looks like a boxer trying to give jabs to his opponent.
Subaru, air cooled VW, chevy corvair all have the same type of engine. Just refers to the engine style is all. I used to have a GIF on a subaru engine that totally explains why its called a boxer. If you were to watch the pistons up in and out, it looks like a boxer trying to give jabs to his opponent.
Solo
[14] Master
I'm sure someone here can explain this better than me but why not have a shot at it. Lol
A boxer engine is where the pistons move like this:
(Ex. Porsche 911's, some Subarus, a few BMW, some motorcycles)
Versus the engines that are in a "V" shape. (Ex. Muscle cars, most exotics)
And Inline engines. (Ex. Economy cars, Civics, most motorcycles)
Here's a rotary engine too for reference. (Mazda RX's)
A boxer engine is where the pistons move like this:
(Ex. Porsche 911's, some Subarus, a few BMW, some motorcycles)
TsunamiBye
[14] Master
Thanks guys. Now I just need to copy this down and be on my way as I learn via texbook and trial and error. Course, I have to ask a lot of questions since I'm an absolute newbie to this stuff. But for now: Where did you all get the inspiration to start doing mechanic work and stuff?
Hot Rod Dave
"Saucy saucy minx"
I was born into it. All my brothers, uncles, cousins, dad, grandpa, even great grandpa Horace cast pistons for tanks in WWI. as you are aware of my last name....its either destiny or a curse.
Juez
DragonPuncher
This thread is interesting.
Slade
[14] Master
I know nothing about cars but I fucking love stupid customer stories.
- Thread starter
- #40
damn-I-Suck
[12] Conqueror
Okay.. I have a new one for you guys..
This one is partly my fault, partly the instructor's.
here goes:
My 1994 Taurus had a major gas leak. It normally is supposed to get 20 MPG average, and then one week it was all-of-a-sudden getting 10 MPG. I smelled gas fumes too. Pretty obvious that I had a fuel leak somewhere.
So anyways.. I get it on the lift and see that the entire tank is wet from gas. I drop the tank and did a smoke machine leak test, sealing all the other lines. The smoke was seeping out of the top of the fuel tank at the actual fuel pump assembly (sending unit, etc), where the metal lines first came out and attached to the rubber lines.
So, anyways, I new I had to eat the cost of a new fuel pump, or get half the millage. Not much of a choice, right?
This car has 223,000 miles on it, so I thought why waste money on an OEM fuel pump that costs me 300 bucks, when I could go get an airtex for 120?
So anyway.. My teacher INSISTED that he install the new fuel pump himself because "he wanted to make sure it was done right". I can understand that.
Only problem is, 3 months later, today I went out to smoke a cigarette and I smelled GAS. I was 30 fucking feet away from the damn car! There was also a very large dark puddle under the car. I go over there, lay on the ground, look under the car, and the damn thing is gushing out gas like you wouldn't believe. Since I don't have a lift at home, I can only guess that the damn 0-ring for the fuel pump isn't seated properly.
So tomorrow I will take the risk of driving the damn thing 5 miles (IF I don't run out of gas) to school, and cuss out my teacher for being a moron and putting me at risk.
The thing is, I didn't actually FILL the tank until this time after the new fuel pump installation, and as soon as I did, BAM gas smell. First my GF noticed a gas smell last night, then I noticed it today.
So I guess even someone with 25 years experience and someone who claims to "know it all", can seriously fuck something up sometimes. Lesson learned: I should have just looked it up on alldata.com for the "exact" procedure (even though I pretty much knew what to do).
Never trust a single individual over the collective information of thousands of technicians. AllDATA.com can be wrong sometimes, but I've come to realize I can trust it WAY more than my teacher.
Sad thing is, I'm starting to think my teacher isn't as good as he claims to be.
So yeah, me and him are going to have HOT words tomorrow.
This one is partly my fault, partly the instructor's.
here goes:
My 1994 Taurus had a major gas leak. It normally is supposed to get 20 MPG average, and then one week it was all-of-a-sudden getting 10 MPG. I smelled gas fumes too. Pretty obvious that I had a fuel leak somewhere.
So anyways.. I get it on the lift and see that the entire tank is wet from gas. I drop the tank and did a smoke machine leak test, sealing all the other lines. The smoke was seeping out of the top of the fuel tank at the actual fuel pump assembly (sending unit, etc), where the metal lines first came out and attached to the rubber lines.
So, anyways, I new I had to eat the cost of a new fuel pump, or get half the millage. Not much of a choice, right?
This car has 223,000 miles on it, so I thought why waste money on an OEM fuel pump that costs me 300 bucks, when I could go get an airtex for 120?
So anyway.. My teacher INSISTED that he install the new fuel pump himself because "he wanted to make sure it was done right". I can understand that.
Only problem is, 3 months later, today I went out to smoke a cigarette and I smelled GAS. I was 30 fucking feet away from the damn car! There was also a very large dark puddle under the car. I go over there, lay on the ground, look under the car, and the damn thing is gushing out gas like you wouldn't believe. Since I don't have a lift at home, I can only guess that the damn 0-ring for the fuel pump isn't seated properly.
So tomorrow I will take the risk of driving the damn thing 5 miles (IF I don't run out of gas) to school, and cuss out my teacher for being a moron and putting me at risk.
The thing is, I didn't actually FILL the tank until this time after the new fuel pump installation, and as soon as I did, BAM gas smell. First my GF noticed a gas smell last night, then I noticed it today.
So I guess even someone with 25 years experience and someone who claims to "know it all", can seriously fuck something up sometimes. Lesson learned: I should have just looked it up on alldata.com for the "exact" procedure (even though I pretty much knew what to do).
Never trust a single individual over the collective information of thousands of technicians. AllDATA.com can be wrong sometimes, but I've come to realize I can trust it WAY more than my teacher.
Sad thing is, I'm starting to think my teacher isn't as good as he claims to be.
So yeah, me and him are going to have HOT words tomorrow.