issue w/ boost spikes? i think?

[NOTORIOUS VR]

Interesting...

I'll have to take a look. I actually have the OE BOV venting to atmosphere right now, so I would normally hear a boost leak... but I will check it out anyways.

It's just very strange that it changed to radically from one day to the next.

Originally Posted by Supra2NR

I have the same problem
And it might be ur blowoff vavle too
Try bowing on it from the front if you can blow thru it , that means its broke

That's why the boost spikes cuz the line is leaking
And sumtimes it revs high and boosts high
Depending on how your driving the car

Jus try to blow on the valve, you might have the same exact problem as I do,the way you described it

[IHateHacks]

If you are both over boosting and under boosting then in my opinion its that rig of a boost controller you are using.

Where did you hook it up at?

Yea, yea I know you said you used it before, but it's not automotive quality and obviously not made for a vehicle. For instance, that regulator is meant to be subjected to just air, well now its being subjected to motor oil and blow-by gases that are very corrosive. Do yourself (or your buddy) a favor and get a real manual boost controller, they are around $100 and alot cheaper than a new head gasket (hint, hint).

You can always take it out and put it back to stock to see if it still over/under boosts. If it doesn't then you found your problem. But I'm willing to bet it didn't do this until you rigged it up.

If the connection was bad between the AFM and the harness, the car would not even run.

And come on, get a real BOV. I did the stock-vent-to-atmosphere thing but a HKS SSQV sounds SO much better.

[NOTORIOUS VR]

Originally Posted by IHateHacks

If you are both over boosting and under boosting then in my opinion its that rig of a boost controller you are using.

Where did you hook it up at?

I understand where you are coming from... The air pressure regulator is connected at the stock locations for the wastegate. So the nipple on the cold side of the turbo goes to the air press. reg. and then to the wastegate.

Yea, yea I know you said you used it before, but it's not automotive quality and obviously not made for a vehicle. For instance, that regulator is meant to be subjected to just air, well now its being subjected to motor oil and blow-by gases that are very corrosive.

You are correct, it's not automotive quality, but it IS industrial quality, which is ment to see many contaminents including oil, dirt, etc, etc.

The only other issue I have with it, is that it's quite sensitive as normally compressed air systems run at a lot higher pressure (nominal is usualy 6 BAR).

Do yourself (or your buddy) a favor and get a real manual boost controller, they are around $100 and alot cheaper than a new head gasket (hint, hint).

I know a real MBC would be better (although not always, I've seen enough MBC's go bad or not last long at all).

And I haven't defeated any of the safety's on the car so fuel cut still happens @ the stock levels (max) boost levels.

You can always take it out and put it back to stock to see if it still over/under boosts. If it doesn't then you found your problem. But I'm willing to bet it didn't do this until you rigged it up.

This I might still try, although I'm thinking that maybe it's the pulsing that's causing the regulator issues now that the lines are shorter? Like I said everything is great until I shortened the lines to the regulator.

I might look into making a ball & spring type MBC myself if all else fails, they're the basics of a good MBC anyways.

If the connection was bad between the AFM and the harness, the car would not even run.

This I figured as w/ most cars with an AFM the car won't run w/o it connected, but I figure since the connector is that loose, and since the problem comes and goes, I thought I'd at least mention it.

And come on, get a real BOV. I did the stock-vent-to-atmosphere thing but a HKS SSQV sounds SO much better.

In due time the owner will be purchasing more performance goodies for his Supra, but for the time being I did that little modification for him. It doesn't bring anything performance wise, but does do a little for the enjoyment of being able to hear (although quiet) the compressed air being vented.

As for the SSQV, I'm not a big fan of it really... I don't think it sounds all that nice :P


Hopefully we'll have some more nice weather days as we've been having here so that I can tinker some more.

Next step for him will be downpipe, exhaust and ARP headstuds, as his brother who put in the HKS gasket reused the original bolts (but he didn't know better).

[Supra2NR]

I have a turboxs mbc
And how do u vent the stock bov to the atmosphere?

[NOTORIOUS VR]

Just take it out of the intake arm, and let it vent.

BUT! Make sure u cap off the intake arm so no unmetered air gets in or else u'r car will run lean.

Originally Posted by Supra2NR

I have a turboxs mbc
And how do u vent the stock bov to the atmosphere?

[Supra2NR]

Wouldn't jus cause a leak
Since the whole system is not completly sealed?

[NOTORIOUS VR]

No, why would it cause a leak? Unless u'r BOV is faulty, there should be no boost leak.

Originally Posted by Supra2NR

Wouldn't jus cause a leak
Since the whole system is not completly sealed?