swapped my .63 for .82 hot side gt35r VIDEO

[jeffp]

It's times like this that a picture would have been worth 4000-5000 dollars to you Phil. You contacted me regarding your fluttering some time ago and I gave you some areas to look at and check. Had you provided me with a few pictures I could have solved your problem in short order. I am sorry you hurt your engine in the process. You should have never tried a dyno pull until you fixed your problem. I am assuming you did not, as I did not take the time to read through all of the posts.

The Turbo: You were way off base changing from the .63 A/R to the .82 A/R exhaust turbine housing. In fact your boost should have come on @ 3200 RPM's in the first place with the .63 housing. The .82 housing should have been used for high rpm levels, and RPM requirements. I made 658Hp at the crank with the .63 housing on the dyno @ 22psi of boost on race fuel.

The boost problem you could not figure out, well as I said a picture would have been invaluable to you when you contacted me. I was able to get a quick look at your turbo outlet in one of your videos and knew what your problem was. I have seen it happen before, and if it makes you feel any better it took some time to figure out by Clark at JWT as well.

Your couplers, the pretty blue ones are your problem! You did not design the inlet and outlet tubing sufficently and it has cost you dearly.

My friend Mark had the very same problem with his car. Seems that under boost the rubber/silicone couplers were sucking in and basically plugging off the turbo inlet/outlet. So as they would suck in, the boost would surge, and as they returned to their designed ID the turbo would again make boost.

So the solution: Every coupler in your case is suspect. My recommendation to you, after you build a new engine, is to run the steel/stainless/aluminum piping whichever the case may be correctly. The tubing should fit almost perfecctly, menaing that you have 1/4" or less between eack tube coupling. Couplers are not used to make your tubing install easier, like in the case of your outlet 90 on the outlet of the turbo, but to connect a well engineered tubing system together and seal them.

You just went through the school of hard knocks Phil, and if you listen to my advice and correct the intercooler tubing gaps between tubes, as well the INLET tubing, if needed, I can assure you the surging you are experiencing will mysteriously go away.

 

REGARDS: jeffp

[S130Z]

I felt like someone needed to play the violin along side of me as i read that last post......

[big-phil]

It's times like this that a picture would have been worth 4000-5000 dollars to you Phil. You contacted me regarding your fluttering some time ago and I gave you some areas to look at and check. Had you provided me with a few pictures I could have solved your problem in short order. I am sorry you hurt your engine in the process. You should have never tried a dyno pull until you fixed your problem. I am assuming you did not, as I did not take the time to read through all of the posts.

The Turbo: You were way off base changing from the .63 A/R to the .82 A/R exhaust turbine housing. In fact your boost should have come on @ 3200 RPM's in the first place with the .63 housing. The .82 housing should have been used for high rpm levels, and RPM requirements. I made 658Hp at the crank with the .63 housing on the dyno @ 22psi of boost on race fuel.

The boost problem you could not figure out, well as I said a picture would have been invaluable to you when you contacted me. I was able to get a quick look at your turbo outlet in one of your videos and knew what your problem was. I have seen it happen before, and if it makes you feel any better it took some time to figure out by Clark at JWT as well.

Your couplers, the pretty blue ones are your problem! You did not design the inlet and outlet tubing sufficently and it has cost you dearly.

My friend Mark had the very same problem with his car. Seems that under boost the rubber/silicone couplers were sucking in and basically plugging off the turbo inlet/outlet. So as they would suck in, the boost would surge, and as they returned to their designed ID the turbo would again make boost.

So the solution: Every coupler in your case is suspect. My recommendation to you, after you build a new engine, is to run the steel/stainless/aluminum piping whichever the case may be correctly. The tubing should fit almost perfecctly, menaing that you have 1/4" or less between eack tube coupling. Couplers are not used to make your tubing install easier, like in the case of your outlet 90 on the outlet of the turbo, but to connect a well engineered tubing system together and seal them.

You just went through the school of hard knocks Phil, and if you listen to my advice and correct the intercooler tubing gaps between tubes, as well the INLET tubing, if needed, I can assure you the surging you are experiencing will mysteriously go away.

 

REGARDS: jeffp

Yes I REALLY need to delete lots of those couplers. But after changing my plugs to iridium with a gap of .020 i thought of you Jeff after the first pull. You told me to make sure the ignition was not the problem. And it damn sure was!! I have my piping as close as possible on each coupler. Take a look at a my video of "before and after plugs" Jeff it pulled strong with out the flutter. I went to the .82 to also solve my boost creep. Now I understand that my waste gate is not in the pefect spot but with the 63 I had over 10 lbs of creep, it was uncontrollible. With the 82 its about 3 lbs.

[goodoldjam]

S130Z said that he runs the same gate setup and sees no creep at 15psi with a smaller housing. I would assume something else is wrong. Maybe it would be worth while to see what's different between your setup and others who have the gate at the same spot. Have you tried another wastegate?

 

Could your wastegate diaphragm be leaking and not opening like it should?

Edited July 12, 2010 by goodoldjam

[jc052685]

Yes I REALLY need to delete lots of those couplers. But after changing my plugs to iridium with a gap of .020 i thought of you Jeff after the first pull. You told me to make sure the ignition was not the problem. And it damn sure was!! I have my piping as close as possible on each coupler. Take a look at a my video of "before and after plugs" Jeff it pulled strong with out the flutter. I went to the .82 to also solve my boost creep. Now I understand that my waste gate is not in the pefect spot but with the 63 I had over 10 lbs of creep, it was uncontrollible. With the 82 its about 3 lbs.

 

 

Phil, it is just my opinion but I am going to have to say that your creep problem is not from the waste gate.

[goodoldjam]

My thinking maybe totally wrong.

You have that dyno sheet with a 9 lb spring that shows that it was fluttering at 25psi beginning at 5k rpm. I'm assuming boost was fluctuating at this time causing the waves on the graph.

If the creep was related to not enough flow, then why would a 9LB spring open and close at all. Wouldn't it be more likely to stay open? It seems as though the valve can open farther, it just needs exhaust pressure and a weak spring to do it. A damaged diaphragm could explain it, higher the boost the more it needs to open but at the same time it could be leaking more.

[jeffp]

maybe it would be best to state your setyp. What wastegate are you running? Boodt creep has nothing to do with the wastegate housing for the most part. True it does flow better then the .63 housing, but the exhaust turbine housing id not what controls the boost pressure, the wastegate does. So if the gate is to small you will get creep. Also the size of the gate should be a Tial 44 or larger. I was running the Tial 46 gate, and it did well for the most part, but I still had some creep, about 2psi. Keep in mind that although the Tial 46 sounds like a bigger unit then the Tial 44 gate, it is in fact not the case. I learned this from a call to Tial support, not a vender or supplier, but Tial support. According to Tial service the Tial 46 was designed specifically for the porsch car due to space constraints. Of course I found out that information AFTER I bought nd installed the 46mm part. The GT35R is good for 650Hp, so if you consider, that 8 apsi of boost on my engine making 300hp, the waste gate needed to vent 350hp worth of exhaust. a 1" pipe outlet simply will not accomplish this task, and you get creep.

How are you venting the inlet, are you running bypassed, or venting to air? I had a problem one time when I just installed my turbo, I vould not get the thing to make anything over 12psi of boost. It took me a few runs, and some adjustments, but it turned out I did not connect the line to the recirculation valve, so the spring being an 11 pound spring opened @ 12psi and vented the additional boost back to the inlet of the turbo.

 

You should be able to run at 8psi of boost all the way to redline, and if you cant do that, you need a bigger waste gate.

 

A misfire generally will cause lack of power, and increased AFR's and boost will not seem to do anything. I guess it is possible that your surging could be caused, by a misfire, but your AFR's would be all over the place, rich lean, rich lean condition. There is something that is changing on the inlet of the turbo that is causing an air flow inconsistancy condition that makes the engine surge. The .82 housing was a waste of your money, and had I known you were doing that change I could have sent you my housing to use as a test mule to save you some money.

Anyway, keep at it and you will find the problem, and when you do I am sure you will be a little disturbed that you did not find it earlier.

Also, if you are required to set your plug gap to .020 then you should look into a bettter coil/coil packs. Also if you are running a single coil setup running the power you should be able to get with the 35R, lose that system, it will not perform to the levels you need, simply put you will never get enough spark duration at the higher rpm levels at that power with a single coil setup due to the cylinder pressures you will have for the power.

[Tony D]

but 25 lbs is allot of boost

 

Sigh... still fixated on pressure.

[goodoldjam]

 

You should be able to run at 8psi of boost all the way to redline, and if you cant do that, you need a bigger waste gate.

 

He mentioned something about how 9psi wasn't a problem in one of the creep videos. What is looking strange to me is that in one of the videos the wastegate is hooked to the back of the manifold. I'm wondering if it's a good thing to have a wastegate go from pressure to vacuum like that. The Tial instructions say to hook up the pressure source before the throttle body. Other people have said that they've ran it off the manifold with no issues, so who knows.

 

Here is a list of some things that could go wrong that someone posted on a Honda forum.

 

-pinched diaphragm

-diaphragm is not sitting correct on the bottom half

-someone took it apart and didn't use locktite on the set screws that hold the valve in place

- you hooked it up to a vacuum source (which is says not to per instructions and i have said numerous times on here) and the vacuum sucked in the diaphragm and slit it

- the washers were not installed correctly (or at all) and the air fitting was screwed in too far hitting/damaging the diaphragm

Edited July 13, 2010 by goodoldjam

[S130Z]

He mentioned something about how 9psi wasn't a problem in one of the creep videos. What is looking strange to me is that in one of the videos the wastegate is hooked to the back of the manifold. I'm wondering if it's a good thing to have a wastegate go from pressure to vacuum like that. The Tial instructions say to hook up the pressure source before the throttle body. Other people have said that they've ran it off the manifold with no issues, so who knows.

 

Here is a list of some things that could go wrong that someone posted on a Honda forum.

 

-pinched diaphragm

-diaphragm is not sitting correct on the bottom half

-someone took it apart and didn't use locktite on the set screws that hold the valve in place

- you hooked it up to a vacuum source (which is says not to per instructions and i have said numerous times on here) and the vacuum sucked in the diaphragm and slit it

- the washers were not installed correctly (or at all) and the air fitting was screwed in too far hitting/damaging the diaphragm

 

 

I am very interested in this. I have heard one of the Admins mention that running the WG reference line off the manifold aids in performance. It helps keep the turbo spooled between shifts and gives you "true" boost to the manifold off the spring. Can anyone else comment on this? Good or Bad?

[goodoldjam]

I am very interested in this. I have heard one of the Admins mention that running the WG reference line off the manifold aids in performance. It helps keep the turbo spooled between shifts and gives you "true" boost to the manifold off the spring. Can anyone else comment on this? Good or Bad?

 

I was interested myself because it's good to know before i connect my external. Tial had no warning about it.

So I emailed them.

 

"I was wondering does connecting the wastegate pressure source to the manifold after the throttle plate cause damage to the diaphragm due to vacuum?

Thanks"

 

Tial Tech

"It could potentially – worse off though you create a vacuum leak

 

 

Jake"

 

I didn't really consider a vacuum leak, but they are not air tight from factory.

Edited July 13, 2010 by goodoldjam

[wigenOut-S30]

I am very interested in this. I have heard one of the Admins mention that running the WG reference line off the manifold aids in performance. It helps keep the turbo spooled between shifts and gives you "true" boost to the manifold off the spring. Can anyone else comment on this? Good or Bad?

 

That is interesting as I have my setup like this. I see boost come on fast and strong. and gets back into full boost really fast after a shift. But I do get about 1-2 psi of creep.. hmm I might hook it up the other way to see if I get the same results.

Edited July 13, 2010 by wigenOut-S30

[sq_creations]

I have tuned a couple cars that have done what your car is doing in the video. In my experience it was the electronic boost controller causing the problem. If you set the boost activation too high it will fluctuate the controller on and off. Ie: your target boost is set to 25 psi and you activation psi is set to 24psi or higher. The activation is too close to the control point. Try setting the activation down to 15 or 20 psi.

[goodoldjam]

I myself can't see a benefit to having it at the manifold as opposed to directly before the throttle body. Your going to get a good measurement after the intercooler which would be almost exactly what the engine sees. As soon as the throttle plate closes the BOV releases the pressure then the wastegate spring should do it's job. Applying vacuum to it may close it faster but It would be with more force.

Edited July 13, 2010 by goodoldjam

[S130Z]

That is interesting as I have my setup like this. I see boost come on fast and strong. and gets back into full boost really fast after a shift. But I do get about 1-2 psi of creep.. hmm I might hook it up the other way to see if I get the same results.

 

My friend and I were tinkering with his RX-7 Turbo II and I proposed the idea of moving his signal line to the manifold. We did this and was surprised to see how much faster boost came on. We could actually hit full boost in 1st gear, as we were not able to do so before.

 

As for letting off the throttle....If you think about it, the sudden vaccuum on the WG will close the WG as to keep your exhaust gasses flowing through the turbine, thus keeping the turbo spinning just a little bit more between shifts.

[S130Z]

I myself can't see a benefit to having it at the manifold as opposed to directly before the throttle body. Your going to get a good measurement after the intercooler which would be almost exactly what the engine sees. As soon as the throttle plate closes the BOV releases the pressure then the wastegate spring should do it's job. Applying vacuum to it may close it faster but It would be with more force.

 

How many people really hook their WG signal to the TB? Most of the time they either hook thier signal up to the turbo or the manifold. This being the most common case(being hooked to the turbo) when your BOV releases, your turbo is still spinning and creating pressure, as well as the intercooler system before the BOV will still be pressurized. This causes the WG to float open a little bit, allowing exhaust gasses to escape......you can figure the rest from there.

[goodoldjam]

How many people really hook their WG signal to the TB? Most of the time they either hook thier signal up to the turbo or the manifold. This being the most common case(being hooked to the turbo) when your BOV releases, your turbo is still spinning and creating pressure, as well as the intercooler system before the BOV will still be pressurized. This causes the WG to float open a little bit, allowing exhaust gasses to escape......you can figure the rest from there.

I understand that thinking, part of the reason i vent before the intercooler because it is a restriction. We know that most wastegates begin to crack at about 50% of the spring pressure, it would make sense that it may float at less. Only question is, should you or would you have enough pressure in the system to keep it floating. If you have enough pressure to keep that valve open and your turbo is seeing that back pressure then you have a greater performance issue. My BOV will open in neutral with a quick blip, it doesn't hold much pressure. I agree that no matter how well it vents it would show some positive pressure. Definitely it could be tested, by checking at what pressure a wastegate actually closes. Then checking the pressure in the system when the BOV opens.

[goodoldjam]

My friend and I were tinkering with his RX-7 Turbo II and I proposed the idea of moving his signal line to the manifold. We did this and was surprised to see how much faster boost came on. We could actually hit full boost in 1st gear, as we were not able to do so before.

 

As for letting off the throttle....If you think about it, the sudden vaccuum on the WG will close the WG as to keep your exhaust gasses flowing through the turbine, thus keeping the turbo spinning just a little bit more between shifts.

I don't see a reason why it comes on faster under WOT. Do you have a theory why it would come on faster? A huge pressure difference between where it was connected before maybe, making the gate open later.

Edited July 14, 2010 by goodoldjam

[S130Z]

I don't see a reason why it comes on faster under WOT. Do you have a theory why it would come on faster? A huge pressure difference between where it was connected before maybe, making the gate open later.

 

If you think about the pressure loss through the entire intercooler system, boost pressure will be more at the turbo(his stock WG source), then at the manifold. The pressure at the turbo reaches max boost before it gets to the manifold. This being said, the WG will start to open later (if plumbed off the manifold) since it will see pressure later down the line.

[boardkid280z]

Sorry to hear about your troubles big-phil. Make any progress yet? Pull those pistons to see if your rings are in pieces?

 

On the plus side, I just wanted to say thank you for the tip on the spark plugs. I've been having a fluttering problem at higher boost/rpm for a while now that I just wasn't able to figure out (I thought it was some setting in Megasquirt or a janky boost controller). Anything over 10psi and I couldn't give it full throttle without a flutter that felt like ignition cut out or timing retard like MS boost control was trying to cut spark.

After reading your thread, I decided to look for some NGK iridium plugs. I couldn't find any locally, but went ahead and pulled my plugs to check the gap, and they were all in the low 40s. Can't remember when I put em in and I don't know why I would have set them so high. Anyway, regapped to 0.025 and the problem went away. Sweet, so easy - it sucks when the problem is so simple and could have been fixed a long time ago. Still would like to find some iridium plugs to help even more. Guy at Autozone tried to sell me these Pulstar plugs or something. $25 per pair ...hmmm. Any opinions? Well, first he tried to sell me the Champions, then the Autolite Iridiums, THEN the Pulstars. I just can't justify $100 for plugs unless they really are awesome.

 

Then I had a major exhaust leak show up 2 days ago at the head. And my hydraulic head has had a lifter tapping for a few months (it gets real bad at the auto-X), so it's about time to swap back to my solid lifter P90, and find out where the exhaust leak is, hopefully a new gasket will fix it.