Intercooler Pressure Drop Test

[simpletool]

Symptoms are saying BOOST LEAK to me

Low power with current boost - tick

Knock with more boost - tick

Overheated compressor wheel - tick

Slow onset of boost?? - tick

Is 6rwhp enough of a gain for dropping the exhaust? only 2%

Edited May 18, 2011 by simpletool

[Hanaldo]

  On 18/05/2011 at 6:27 AM, simpletool said:

Symptoms are saying BOOST LEAK to me

Low power with current boost - tick

Knock with more boost - tick

Overheated compressor wheel - tick

Slow onset of boost?? - tick

Is 6rwhp enough of a gain for dropping the exhaust? only 2%

It's a very free flowing exhaust...

Would a boost leak not show up when I did the pressure test? Given I took the reading from just after the turbo and then from the MAP sensor just before the manifold? If there was a boost leak, wouldn't the pressure at the turbo be greater than the pressure at the manifold, even if the pressure at the manifold was 16psi? Assuming the leak is between those two points, but where else could it be leaking from?

Which brings me to another point; Stao, if the issue here is a low reading dyno. Why did the comp wheel on the turbo I sent back to you show it had been working too hard?

Edited May 18, 2011 by Hanaldo

[hypergear]

I think its a very low reading dyno as its reading low through out all rev ranges including the range that is on negative boost level, while the shape of curve appears to be identical to the other 3.

Also the comp wheel that sent back appears to be in pail white, while they originally has a light blue materal appearance. It means the comp wheel had very hard time pumping air through. How ever that does not affect the pre-boost power level.

[urtwhistle]

well if its that recent then it's ovaboosts dyno which reads very close to Hyperdrives, How do I know? cos my car has been on both with in a week of each other. I seriously think your chasing the problems in the wrong area's. Print and overlay yours onto my sheet or mine onto yours and scan it and post it on here. That way we can compare and see possible reasons to why its not making power. I can barely see on those print outs. But it looks like its exactly the same untill about 5krpm then it slowly comes up to where mine was.

have you got prints with the boost graph. That would be very interesting to compare. I originally ran the standard wastegate, then I put on small can 14psi wastegate that Stao supplied and my car ran like shit. Then he supplied me a big can 14psi wastegate and it ran a lot better from that day onwards.

What area do yo live , PM me and you could borrow it and test how it or compare setups. (since there so damn close)

[Hanaldo]

  On 18/05/2011 at 12:53 PM, urtwhistle said:

well if its that recent then it's ovaboosts dyno which reads very close to Hyperdrives, How do I know? cos my car has been on both with in a week of each other. I seriously think your chasing the problems in the wrong area's. Print and overlay yours onto my sheet or mine onto yours and scan it and post it on here. That way we can compare and see possible reasons to why its not making power. I can barely see on those print outs. But it looks like its exactly the same untill about 5krpm then it slowly comes up to where mine was.

have you got prints with the boost graph. That would be very interesting to compare. I originally ran the standard wastegate, then I put on small can 14psi wastegate that Stao supplied and my car ran like shit. Then he supplied me a big can 14psi wastegate and it ran a lot better from that day onwards.

What area do yo live , PM me and you could borrow it and test how it or compare setups. (since there so damn close)

I assume you are talking about the actuator? I'm using a 20psi actuator.

I don't have a print out with boost, Ovaboosts dyno can't log boost. I'll overlay the charts I have.

[simpletool]

Hard to concentrate right now but in my mind a boost leak won't show up in a leak test if the leak is not between the measuring points.

ie. think outside the circle.... your engine is a MASSIVE boost leak...but it doesn't show up as it is after the final measuring point. Check all the hoses and connections from the manifold...where do they end up?

Obviously it might be something else but boost leak seems very possible and relatively easy to sort out.

Edited May 19, 2011 by simpletool

[urtwhistle]

its easy to test for a pressure leak. all you need is a $2.00 pvc fitting from bunnings and a cricket ball. I will take a photo tonight and show you how to do it.

PS I think your missing the point about the actuator. the PSI rating is irrelavant. Its the surface area on the diagphram inside the can that makes a very large difference to how quickly it reacts.

And I find it extremly strange that a company like Ovaboost can't log the boost response. it's 1 of the most simple tools that they would use.

[Beer Baron]

  On 19/05/2011 at 4:44 AM, urtwhistle said:

its easy to test for a pressure leak. all you need is a $2.00 pvc fitting from bunnings and a cricket ball. I will take a photo tonight and show you how to do it.

PS I think your missing the point about the actuator. the PSI rating is irrelavant. Its the surface area on the diagphram inside the can that makes a very large difference to how quickly it reacts.

And I find it extremly strange that a company like Ovaboost can't log the boost response. it's 1 of the most simple tools that they would use.

well it's no wonder they call themselves ovaboost. if they can't measure boost on the dyno I guess they would have some trouble setting up EBCs nicely..... jk.

[kwickr33]

I think the flow restriction isn't about a leak. Ie 30psi after turbo and 15psi on in the inlet manifold means some thing is restrictive on the way. Also noticed you are running a 600x300x100mm cooler, thats a massive cooler for this turbo, will make it laggy.

[Hanaldo]

  On 19/05/2011 at 4:44 AM, urtwhistle said:

its easy to test for a pressure leak. all you need is a $2.00 pvc fitting from bunnings and a cricket ball. I will take a photo tonight and show you how to do it.

PS I think your missing the point about the actuator. the PSI rating is irrelavant. Its the surface area on the diagphram inside the can that makes a very large difference to how quickly it reacts.

And I find it extremly strange that a company like Ovaboost can't log the boost response. it's 1 of the most simple tools that they would use.

I see, I'll talk to Stao about that one.

Was a bit surprised myself about their not logging boost. My tuner told me to come back when he has his dyno up and running and he will give me a free run on the dyno so he can see what it does properly.

  On 19/05/2011 at 5:14 AM, Beer Baron said:

well it's no wonder they call themselves ovaboost. if they can't measure boost on the dyno I guess they would have some trouble setting up EBCs nicely..... jk.

Lol

[MrStabby]

  On 19/05/2011 at 5:14 AM, Beer Baron said:

well it's no wonder they call themselves ovaboost. if they can't measure boost on the dyno I guess they would have some trouble setting up EBCs nicely..... jk.

Teh Lulz.

And yes there's no way to measure a boost leak because the all connected bits of pipework will have close enough to the same pressure (assuming there's no big restriction in there). You would have to measure air flow either side of the leak.

[Hanaldo]

  On 19/05/2011 at 6:33 AM, MrStabby said:

Teh Lulz.

And yes there's no way to measure a boost leak because the all connected bits of pipework will have close enough to the same pressure (assuming there's no big restriction in there). You would have to measure air flow either side of the leak.

Ah yes, good call. I knew something didn't add up about what I said. Brain no worky after uni

However, wouldn't a boost leak be a vacuum leak while not on boost? The car drives fine, doesn't feel like it has any vacuum leaks...

[XRATED]

Alot of silicone can split and only open up under pressure...

If it's a boost leak, then it will account for why the comp wheel looks well over spun too.

J.

[Hanaldo]

  On 19/05/2011 at 7:50 AM, XRATED said:

Alot of silicone can split and only open up under pressure...

If it's a boost leak, then it will account for why the comp wheel looks well over spun too.

J.

Would the engine not run rich if this were the case? Suppose if it has been tuned with it then it would not...

Leak test it is then.

[MrStabby]

  On 19/05/2011 at 8:28 AM, Hanaldo said:

Would the engine not run rich if this were the case? Suppose if it has been tuned with it then it would not...

Yep, you're right it would be rich, but tune may be hiding it, and if that's the case you'll need a retune after..

[paulr33]

yep i had split vac lines on my GTST for ages

only when stressed them out you could see it split

i ended up replacing them twice, same issue

finally went with thick fuel hose, problem solved

no more splits

it was always on the actuator signal vac line

[urtwhistle]

unfortunatelysince my motor is out it was a little hard to get a good photo.

But as you can see remove the cross over pipe and block it with a pvc pipe end cap (use pipe clamps). remove the pipe from the pressure side of the turbo. jam a cricket ball or another PVC fitting in t. You can either pressurise the system through the bungs that you run to your waste gate or leave them all hooked up and drill a hole in 1 of the pvc fittings. I set the regulator on my air compressor to about 20-30psi. Ay that pressure it is very easy to hear a leak.

The main leak on my car was where the inter cooler had a bracket attached to the bottom. They had accidentally drilled into the core. Which I ended up blocking with araldite.

I hope that helps.

[Hanaldo]

  On 19/05/2011 at 1:09 PM, urtwhistle said:

unfortunatelysince my motor is out it was a little hard to get a good photo.

But as you can see remove the cross over pipe and block it with a pvc pipe end cap (use pipe clamps). remove the pipe from the pressure side of the turbo. jam a cricket ball or another PVC fitting in t. You can either pressurise the system through the bungs that you run to your waste gate or leave them all hooked up and drill a hole in 1 of the pvc fittings. I set the regulator on my air compressor to about 20-30psi. Ay that pressure it is very easy to hear a leak.

The main leak on my car was where the inter cooler had a bracket attached to the bottom. They had accidentally drilled into the core. Which I ended up blocking with araldite.

I hope that helps.

Thanks mate, I'll give it a go when I service my car in the coming week. Going to do a compression test at the same time.

Although... I don't understand how you have done it. Surely all you need is to remove the intake pipe to the turbo. Block the turbo inlet with PVC end pipe, and pump air into there? So everything works exactly how it would if the car was running?

[kwickr33]

have a look at this:

http://www.skylinesaustralia.com/forums/topic/364723-gt3076-tuning/page__view__findpost__p__5821894

This guy's made super laggy 255rwkws of a GT3076 on 20psi with adjustable cam gears and cams as well as big inlet and exhaust manifold plus bunch of other mods on hyperdrive's dyno and tune. Its either the tune's really retard or the dyno is very out.

Edited May 19, 2011 by kwickr33

[Hanaldo]

  On 19/05/2011 at 1:28 PM, kwickr33 said:

have a look at this:

http://www.skylinesa...ost__p__5821894

This guy's made super laggy 255rwkws of a GT3076 on 20psi with adjustable cam gears and cams as well as big inlet and exhaust manifold plus bunch of other mods on hyperdrive's dyno and tune. Its either the tune's really retard or the dyno is very out.

Doesn't look that laggy? I have seen an R34 make 280rwhp on the standard turbo at 14psi on Hyperdrives dyno. Another 34 I know of made just over 400rwhp on a HKS GTRS (unsure of boost). It's not like all cars coming out of Hyperdrive are underpowered and laggy.