TECH TALK - ask your technical car questions

[Striker94]

ummm, call me a outsider, noob, whatever, but although i love cars, I know just about nothing about the engine.

This is just one of my completely random queries-Why is Honda the onlny company to utilise V-TEC across most of its car range? Isn't it supposed to be able to save fuel, add power(not sure about that...) and improve performance???

I know that many other cars have it, but why is Honda the only one to advertise it???

[boganbusman]

You are correct in thinking that many manufacturers use variable vavle timing systems on their engines, but they are all different in design and operation.
VTEC is the system that Honda designed, whilst VVT is a system that Toyota designed. Other companies don't neccesairly have a name for their system. That's all there is to it, really.

If you want to know the specific differences between all the various systems, well that is a whole other topic that we can leave for another day . . . perhaps when you are a bit older. You would need to (at least) understand basic engine and valvetrain operation first.

[chimpzrl]

So how can you change the way the valves open? Is there a different set of cams? Do they move? I have heard tell of electronic valve control. Is that the way they are going?

[boganbusman]

So how can you change the way the valves open? Is there a different set of cams? Do they move?

Valve operation is broken down into three main properties: Lift, Duration and Timing.
Simple systems will only alter the timing, but most can now handle the duration and lift as well.

So, to answer your question, I'll give a basic rundown of a few different well-known systems:
VTEC: Has two different cam profiles on the camshaft and electronically switches between them. Alters Lift, Duration and Timing.
VVT: Has an actuator mounted inside the cam sprocket which is operated by oil pressure. When activated, it rotates the cam to alter the timing. Does not alter Duration or Lift. A similar system to this is what you will usually find on cheaper cars.
VVTL: Similar to VTEC.
MIVEC: Similar to VTEC, but its operation is purely dependant on oil pressure and engine speed, with no electronic control.
Ferrari: Each indiviual cam lobe has two profiles that blend into each other in the middle. The vavle operation is modified by simply sliding the camshaft longitudinally. Since the two profiles blend together, you have almost infinite range between each one, which makes the operation very smooth and optimises output throughout the rev range (rather than having an abrupt 'switch' when you change profiles). Alters Lift, Duration and Timing.

I have heard tell of electronic valve control. Is that the way they are going?

I assume that you are referring to solenoid vavles. I've heard that a few manufactures are currently researching this idea, but nothing has been put into production yet. It sounds like a really great idea though, and yes it will probably be "the way they are going". It'll make my job easier, thats for sure

[viper16]

this is a dumb question. next weekend im helping my friend swap an SR into his PS13 what id like to know is since he drifts alot will he need rocker arm stoppers and will they break after repeted revving

[boganbusman]

I'd say it depends on how many rpm he is going for. If he's taking it above 7000rpm on a regular basis then it's probably a good idea. Otherwise I wouldn't worry.

[Striker94]

yeh, thanks for the extended list...

by the way, what is your job?

[boganbusman]

Click on my avatar image.

[Striker94]

mechanic eh?

that would be a interesting job...

I'm considering engineering/accounting/architecture...

[Jopuma]

How far would you guys go (in terms of distance) to get a 90 Supra for $5k? Here's the specs on it.

1990 Toyota supra turbo targa 5-speed, 25k on motor, runs perfect, very fast, DDP BIC downpipe, turbo xs dual stage boost cont. greddy HG, excellent condition!

Installed Features

* Driver Air Bag
* Anti-Lock Brakes
* Alloy Wheels
* Cruise Control
* CD Player
* Rear Window Defroster
* AM/FM Stereo Cassette
* Power Door Locks
* Power Mirrors
* Power Windows
* Power Steering
* Power Seats
* Sunroof/Moonroof
* Tinted Glass
* Tilt Wheel

[chimpzrl]

I think a big road trip home in a brand new (to you) car would be awesome! You get to enjoy it for hours on end right away.

I'm not sure where you live, though. Could be it's not practical where you are.

P.S.-Watch the window tint. Could be he did a bad job or, more importantly, it could be legal where he is and not legal where you are.
This happened to my friend when he bought his Jetta. The window tint was too dark and he had to pay to get it removed and redone.

[Jopuma]

Yeah it would be a road trip from New Mexico (where the car is located) and I'd be driving all the way back home to Denver, Colorado. I looked at some pictures of it and I don't think the tinting is too dark. It seemed to be in very good condition considering it had 230k miles on it.






Color of the car seems a bit iffy to me, but I could probably just get it repainted when I get it back home. That is if and only if I get it.

[viper16]

go get it thats a good deal on a JZA70.

[Jopuma]

The only problem is it's 381 miles from home.

My dad said he would only be willing to take me around 200 miles to get a car. Looks like I gotta buy a train ticket to New Mexico.

(not going to fly. 2 reasons. 1 too expensive. 2 I'm altophobic [afraid of heights])

With the price on that and with how good condition the car is this would be a steal.

[S2000_Skyline12]

Nice

Lol...I get why it's Altophobic, Alto is tall in spanish xD So I guess that could be translated into height haha

[Jopuma]

DANGIT! My dad said no.

He first saw the car, what it had, and all that then he saw the price and where it was. "I'd rather prefer you get something in this in-state and around $2, because buying from a private seller like with that car means you have to pay cash and I don't have $5,500 lying around."

Now I'm bummed. It was a killer nice Supra, but ah well gotta look somewhere closer to home.

[Striker94]

Something around $2? You're gonna have a bit of trouble...

[boganbusman]

go get it thats a good deal on a JZA70.

It's an MA71. The JZA70 has the 1J motor.

At 230k miles, I'd doubt that all the electrics work, and the T-top probably leaks. That one also has the adjustable struts, which are most likely original and completely stuffed.

Your dad has the right idea. $5500 is a lot, and even though it's a Toyota, those older Supras are kinda high-maintenance.

Also, since you're scared of heights, you probably have an undiscovered fear of going sideways too. Don't buy a Supra for your first car, especially a turbocharged one.

[steelsnake00]

Your dad has the right idea. $5500 is a lot, and even though it's a Toyota, those older Supras are kinda high-maintenance.

I had to double take when I saw the price. Here, you can pick up a fairly mint condition Mk3 Supra turbo for about £1000. And the turbo's positively murder head gaskets and other engine internals.

[viper16]

Your dad has the right idea. $5500 is a lot, and even though it's a Toyota, those older Supras are kinda high-maintenance.

I had to double take when I saw the price. Here, you can pick up a fairly mint condition Mk3 Supra turbo for about £1000. And the turbo's positively murder head gaskets and other engine internals.

thats why you swap in a 2JZ and you wont have any problems

[steelsnake00]

thats why you swap in a 2JZ and you wont have any problems

Or you could just buy a car built to take the engine in the first place and save yourself a whole ton of hassle .
People on this forum, eh? Either 13 or scraping the barrel when it comes to intelligence. Though there are some worthwhile people here

[Jopuma]

Something around $2? You're gonna have a bit of trouble...

Already found some cars in pretty decent condition.

At 230k miles, I'd doubt that all the electrics work, and the T-top probably leaks. That one also has the adjustable struts, which are most likely original and completely stuffed.

Your dad has the right idea. $5500 is a lot, and even though it's a Toyota, those older Supras are kinda high-maintenance.

Also, since you're scared of heights, you probably have an undiscovered fear of going sideways too. Don't buy a Supra for your first car, especially a turbocharged one.

Thanks for the tip. As for the "sideways" thing I assume you're talking about drifting or something. Like hell I'm gonna do that. I just want my car to get me from A to B and if absolutely necessary in those annoying situations (like today. everything was going so SLOW!) from A to B really fast.

I had to double take when I saw the price. Here, you can pick up a fairly mint condition Mk3 Supra turbo for about £1000. And the turbo's positively murder head gaskets and other engine internals.

Dangit.

I sometimes hate you Europeans. You can find so many nice cars at very decent prices.

thats why you swap in a 2JZ and you wont have any problems

I neither have the time nor the insane amount of money required to do something like that.

Or you could just buy a car built to take the engine in the first place and save yourself a whole ton of hassle . People on this forum, eh? Either 13 or scraping the barrel when it comes to intelligence. Though there are some worthwhile people here

[Zero260]

Yeah, I think that Supra would be a bit much for a car with the purpose of just going from point A to point B. Probably would have killed yourself on the way back to Denver... That is if it didn't break down on you.

Look at something nice and reliable, yet fun. I've been really happy with my Prelude as a first car. Try something along those lines. Reliable, fun to drive, plenty of potential performance wise if you get bored with it, and has a lot to offer learning wise. I've learned a lot from my car...

[Jopuma]

What about an 89 Mustang GT SE Convertable for $1.5k?

Or a 98 Mustang for $3?

[viper16]

NO the 89 will need alot of work most likely a new top new motors to run the top. as for the 98 its a V6 also underpowered and will have the same problems its a 10 year old car. good thing to remember a 3K will have 3K or more in repairs