300rwkw Unrealistic

[marco]

Im New to this Turbo arena. But I do query this BA "Valve Spring" business.

Who came up with the Idea that the BA valve springs are off?

Was it discovered when Nispro revved a XR6T to 7000 and was making 1000hp?

Well of course ANY valve spring would have trouble with that.

Looking throught the "drag ET" thread, I notice a lot of guys are saying that the XR6T gets better performance (even modded), when letting the car shift itself, and not use the stick, and other chaps are saying that revving more than 5500 is a waste of time and can actually slow you down (some truth to that).

Now...at revs around 5500, unless you have REALLY REALLY Bad valve springs, your not putting too much strain on the hole business. Its usually easy to feel when valve bounce occurs, as the car lays down and you get a lot of popping and banging.

I have no problem with my 03 BA, though admittingly Ive bought it S/H and have NO idea of its history.

All I know is it goes well, seems stock std and Im happy with it.

What I find interesting, is when you research road test for these Trubos.

The F6 is suppose to be 270kw (vs 240 XR), has the second cai, 9psi blow, lpg rods, minor edit and that's about it.

Yet, Most of the times the F6 runs are anywhere tween 14.70s to 14.20s (road tests this is)

When the first XR6T was tested against the SS in Motor in 2003, she ran a 14.14....Qwicker than most F6 tests, AND that was with the slow 5 speed manual, which was critizised in the test as having a bad/Slow shift.

So, knowing as we do, If they tested an auto, it would have run in the 13s...stock (the SS run 13.98)

Dont believe everything some Dyno Jockie tells you. Take it with a pinch of salt.

Too easy to fudge dyno #'s.

[Dirty32]

Marco - I believe its pretty rare to have problems with the springs on a stock car (but there have been some mentions of it), so I dont find it unusual that you have not had a problem with it.

It usually occurs with BA's and early BF's that are taken to over 280 - 300 at the wheels.

A lot of people have actually mentioned that once the valve springs are changed to stronger aftermarket units, the car feels a whole lot stronger in the top of the rev range...

As with BF's built from June 06 onwards, they all had F6 bottom ends, thus stronger valve springs and that would seem to be why the majority of complaints will be from BA's and early BF's...

So what is it that your not sure of?

[XRPete]

  marco said:

Im New to this Turbo arena. But I do query this BA "Valve Spring" business.

Who came up with the Idea that the BA valve springs are off?

Was it discovered when Nispro revved a XR6T to 7000 and was making 1000hp?

Well of course ANY valve spring would have trouble with that.

Looking throught the "drag ET" thread, I notice a lot of guys are saying that the XR6T gets better performance (even modded), when letting the car shift itself, and not use the stick, and other chaps are saying that revving more than 5500 is a waste of time and can actually slow you down (some truth to that).

Now...at revs around 5500, unless you have REALLY REALLY Bad valve springs, your not putting too much strain on the hole business. Its usually easy to feel when valve bounce occurs, as the car lays down and you get a lot of popping and banging.

I have no problem with my 03 BA, though admittingly Ive bought it S/H and have NO idea of its history.

All I know is it goes well, seems stock std and Im happy with it.

What I find interesting, is when you research road test for these Trubos.

The F6 is suppose to be 270kw (vs 240 XR), has the second cai, 9psi blow, lpg rods, minor edit and that's about it.

Yet, Most of the times the F6 runs are anywhere tween 14.70s to 14.20s (road tests this is)

When the first XR6T was tested against the SS in Motor in 2003, she ran a 14.14....Qwicker than most F6 tests, AND that was with the slow 5 speed manual, which was critizised in the test as having a bad/Slow shift.

So, knowing as we do, If they tested an auto, it would have run in the 13s...stock (the SS run 13.98)

Dont believe everything some Dyno Jockie tells you. Take it with a pinch of salt.

Too easy to fudge dyno #'s.

How do you know the springs haven't been changed in yours before you bought it?

I think most people changes springs for peace of mind also. If your spending a couple of Grand on mods roughly $900 bucks is cheap insurance.

[howitzer85]

Insurance to what? I don't think abit of valve float is going to make anything go bang...(could be wrong?) it'll just hurt power in the top end.

its a lot of coin to be throwing at something that might not be required...

[XR06T]

I get valve float occasionally with just a generic 10psi tune. never rev past 5k.

[PHANTMXR6]

  howitzer85 said:

Insurance to what? I don't think abit of valve float is going to make anything go bang...(could be wrong?) it'll just hurt power in the top end.

its a lot of coin to be throwing at something that might not be required...

Oh it can go bang. In a big way. It might not happen the first twenty or so times that it happens, but it only takes one.

If your valves are floating imagine the force exerted on the cam lobes when the valve stem tips are rocketted back up on the return stroke.

This can cause camshaft failure and if a piece of cam causes a valve to stay open then the possibility of valve coming into contact with piston is quite real.

And, if this happens at 5000rpm+......................

All I can say is ouch. To the engine and the back pocket.

Your better off being safe than sorry. And really, it's not that much of an outlay to be on the safe side.

[BAman]

Valve springs are good security.

Things like seat pressure and coil bind come to mind.

A standard valve spring will move around on its retainer causing harmful harmonics and excessive wear.

Your car will still make power but your springs are being forced onto their retainer is very likely to fail at the coil.

You will soon enough loose seat pressure and power will diminish and the standard spring will get weaker and weaker until it fails, and when it does fail you will certainly know about.

Sometime you have to do modification the help you make the power.

You'll be surprised how much smoother your motor will be and how willing and easier to rev.

It's important to have valve spring seat pressure especially on a turbo car to insure tight contact between the valve face and the valve seat.

This provides proper heat transfer from the valve to the cylinder head.

Remember if the valve bounces, cylinder pressure and power is lost.

If it happens over and over in time the head of the valve will deform & break from the valve stem resulting in engine failure.

If you modify a car do it properly, but at the end of the day its your car and its really easy to make lots of power, but have you made it safely??

[bda12pleaseu]

wow look what I started hehehe...

[Maximus]

Remember just it is just insurance.

You hope you never need it but when you do you are safe.

Here is a video explaining it.

[ENVY-T]

Don't worry about it MAximus, let the know it all n00bs work it out for themselves.