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Huge Boost Creep


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im still confused

put the gate on the manifold and set it all for 20psi .. does it make and hold 20psi ?

i can see you saying to want it to run as low as 5psi ... but why ? there is no benifit of a setup that can run 5 psi, since once you get it to run 5psi .. you'll need to upgrade the springs to get it closer to your target.

im not having a go here, im just trying to suggest working for your target boost number OR power target and not well below it is the best approach.

15psi spring in the gate, thats the lowest he can go, and its not an unreasonably low amount of boost, it should be able to hold it there, but it cant, it spikes up and over 20psi

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So when you say that you removed the WG completely did you remove the 30cm or so of pipe down to were the WG was or did you just cut the WG flange off at the end of the pipe?

You do realise that the pipe itself will have a flow resistance and will create it's own back pressure that will increase with length. So if you kept the 30cm of piping that ran down to your WG then that is your problem because that will be causing the back pressure that will be causing your spiking.

This is why cris is saying the the WG has to be as close the the collector/manifold as possible to reduce the flow restriction caused by the length of pipe that ran to the WG.

Edited by D_stirls
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A few things Andrew. From the first dyno graph you posted, and emailed me, the boost goes to 13psi with no gate on there, maybe it would have gone a bit higher, 15-16 tops by redline. Your now saying it tops at 13. which as I said, I would at least expect by cutting off that pipe going down to the ground. Can you please post up a pic of your gate setup now, with it on the car and the wastegate pipe cut off?? So its up the top now?? You make it sound like you've done this, but somehow I get the feeling you've just run another outlet and refitted it, picture will tell a 1000 words.

Second to that, I would expect a decrease in boost had you cut that pipe off, hence backing up my previous statement that it was a complete waste of your time and money to add a second outlet, which I told you would make no difference, I offered you a 60mm gate, brand new, for $450 change over including modifying the manifold with a gaurantee it would work. Why are you also making statements that I never bought up the 60mm gate before?? What a crock!! I discussed it with you numerous times before you touched the manifold last week!. It is starting to come across more and more to me that your just trying to blame me and make me look bad, which just doesn't float mate, if you'd done a single thing I'd said to so far we my have gotten some results.

Where has this majical 5psi thing come from?? I ask you, if the gate offers no restriction, so when its fully open under boost, if it could pass ENOUGH AIR for your application, would it still not hold 13psi of boost as the manifold does with no gate?? It should. Also, maybe you should try calling some workshops with big hp experience and ask them about manifolds, Bresciani Racing would be a good one. Years ago I used to deal with them, and it came about because one of my mates has a manifold on his RB30 that would hold 14psi with no gate on there, he told john who said "who made tha manifold? Get him to call me, thats a good manifold". Your not waking up to the fact that cheap shit stainless chinese manifolds have the gate coming out of the BOTTOM at 180 degrees to the flow, and hold boost with a 38!!!mm gate. So whats it tell you that at the angle mine does, and has issues with a 44?? Thats it works incredibly well at reducing back pressure, increasing velocity, and scavenging.

You can go on about this all day mate, but the fact is, I have 400 other cars and RB manifolds with little or no boost control issues, and less than you could count on your fingers and toes that do. Rather than jump up and down and look for someone to blame, listen to what I originally said when you first called me with a problem, that every application is different, 98% work fine with that setup, I can't account for the very few that have problems, and my ADVISE would be to fit a 60m gate. Been there, done it, fixed it. This whole 13psi with the gate off biz is just annoying me, as if the gate flowed enough, it would hold 13psi with the gate ON. Higher boost with no gate on there is an indictaion of a good manifold and a very efficient and well setup combination, not poor design.

6BOOST

PS, please put up a dyno graph with the runs you did with the outer spring removed from the gate, how I told you the spring reduces valve travel?? And make restrict flow?? The graph should come up to 5psi and climb as it revs out, much like the 15psi one, just starting at 5. Also a pic of the current setup.

I want to help, I really do mate, but looking for someone to blame won't help either of us.

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hey kyle.

my apologies for not explaining myself cleaer. ill try give it another go answering the questions that you have asked.

as i havnt seen the car myself due to certain cercumstances i have gotten updates from my tuner instead.

his told me that he has cut off the wg pipe that comes off the manifold and mounted the wastegate there(im not sure if he made a lil flange but he gave me the impression it was pretty close to the manifold)

as soon as i can get a picture of the setup and dyno graph kyle i will defiantly post it up. no one wants this fixed more then i do trust me.

what i meant when i said you never mentioned a 60mm gate was when i came to you asking for a manifold. not when i told u there was a problem. originally when i 1st spoke to you i told you my setup and asked you what you recommmended for a gate size for a initial boost target of 20psi. you said a 44mm gate should be more then enoguh. so i buy the gate and set everything up, only to get this problem. and your solution was now a 60mm gate. not trying to make u look bad kyle but i sorta feel a bit down about that.

as for the magical 5psi. i merely meant that if we modified the manifold to where it was only producing around 5psi of boost with no gate on it, i would cut my losses and accept that. originally i wanted a manifold that would make no boost wat so ever but with the amount of trouble this has caused i just cbf.

the only reason why i turned down your offer of a 60mm gate + a modified manifold, was because a 44mm gate should be big enough......theres countless setups that i have looked at (obviously not as much as u) that all run 44mm gates and are able to hold as lil as 10psi. everything points to the manifold. and i was upset that i paid money for a manifold that wasnt doing wat it was supposed to do.

the fact that i have to spend another 500bux wen it should have worked in the 1st place is wat upsets me. i budgeted this project with a limit....and its going more and more over....i jsut dont wanna spend anymore money when it should already be workn.

like i said above kyle absolutely no offense to you what so ever. i just feel jibbed that i bought a manifold off you, was recommended to use a 44mm gate...and the combination hasnt worked...and now is costing me extra to fix.

id be more then happy to speak to you privately about the matter, just call or leave me a msg/email anytime.

otherwise ttus

Edited by R34NRG
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I don't get it, you bought the 44mm gate as it works with the manifold when installed in the *proper* designed way. Wouldn't it just make sense to install it as originally designed, then sit back and be happy?

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I don't get it, you bought the 44mm gate as it works with the manifold when installed in the *proper* designed way. Wouldn't it just make sense to install it as originally designed, then sit back and be happy?

lol

yes u are right dan but the problem is the car is not holding boost. it keeps makn more and more and more boost. so when i set the boost to 20. it shoots to 25+

the reason it does this is because the car is making to much air because its a 3.0L. and the manifold is unable to bleed off the air to the gate to reduce/hold boost.

if you dont understand how boost is made, you wont understand this topic.

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lol

yes u are right dan but the problem is the car is not holding boost. it keeps makn more and more and more boost. so when i set the boost to 20. it shoots to 25+

the reason it does this is because the car is making to much air because its a 3.0L. and the manifold is unable to bleed off the air to the gate to reduce/hold boost.

if you dont understand how boost is made, you wont understand this topic.

I know exactly how boost is made, in fact so much so that I know the gate shouldn't be bleeding "air" :)

I find it very hard to believe that you've had the gate taken off and a giant f**k-off gaping hole hasn't tapered the boost off at all....something is fishy, either what's being done is a bit "chinese whipsers" with what's being relayed in this thread, or someone has f**ked up somewhere.

Good luck though as I've got the opposite issue with boost dropping off due to some mystery issue (may be the exhaust cam has bee firgged with in the past) and it's now a year and coutning trying to fix that issue.

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...but the fact is, I have 400 other cars and RB manifolds with little or no boost control issues, and less than you could count on your fingers and toes that do. Rather than jump up and down and look for someone to blame, listen to what I originally said when you first called me with a problem, that every application is different, 98% work fine with that setup, I can't account for the very few that have problems, and my ADVISE would be to fit a 60m gate.

...So whats it tell you that at the angle mine does, and has issues with a 44?? Thats it works incredibly well at reducing back pressure, increasing velocity, and scavenging.

Above is the crux from what i can tell. 20 issues (fingers + toes), 400 cars = 95% of the time things go normally. Its not Lego, so millage can vary.

My understanding is super efficient m.folds like Kyle's, allow gas to so easily enter the turbine, bleeding enough off to get a low boost level can be hard. Kyle's above china example is a good one. Collectors are often so crappy, that extra backpressure before the turbine, means the gate doesn't have to work so hard (limiting chances of over boosting)

A 3582 .82 isn't huge on a 3L too.

Issues suck man, but just work through em, with grace :(

From what your tuner has said, am i right in thinking that there are two 44mm holes in the collector, and theres still issues?

On another note, I shudder to think how the second bleed as been (or not) blended in.

EDIT: Didn't F5 :)

Edited by GeeTR
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I find it very hard to believe that you've had the gate taken off and a giant f**k-off gaping hole hasn't tapered the boost off at all....something is fishy, either what's being done is a bit "chinese whipsers" with what's being relayed in this thread, or someone has f**ked up somewhere.

thats exactly wat im thinkin. how f*kn weird huh? its bloody making 15psi of boost with a gaping hole in the manifold.

how do u explain that? other then the manifold is unable to flow air to the gate....

theres nothing Chinese on my car at all, although it would of saved me a ton of money....and everything is set up the same way as the tuner has done it with all his cars. but for some reason the added .5 of a litre is causing problems left right and centre.

ill go have a look at the car on monday to see wats happening. and come back with pictures and dyno charts

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Probably checked already but have you checked te accuracy of the gauge (or whatever) you are reading the boost from?

Have you considered butchering the ex housing and running the gate from that? Might allow the gate to actyally flow some gas as opposed to trying to redirect them at that crazy angle.

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the 'guage' reading the boost is a dyno-dynamics dyno thats sees way too many cars on it to not show up a faulty sensor like that

666DAN, yes, with a big gaping hole in the manifold, the car made 13psi @ ~5000rpm and was still steadily climbing

GeeTR, the new pickup for the wastegate is right under the turbo flange, sort of angled with the direction of flow, pointing up and off to the side of the turbo flange, and its on the very right side (looking at front of the car) that was the last time i saw it, i believe it was then blended in with the other one before the gate, but dunno whats happened since then

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how are you controlling boost? (with everything plumbed up)

you shouldnt worry what its doing with the boost with everything unplugged, you should be worried what its doing with everything hooked up as per it would be day in day out when ur driving the thing

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how are you controlling boost? (with everything plumbed up)

you shouldnt worry what its doing with the boost with everything unplugged, you should be worried what its doing with everything hooked up as per it would be day in day out when ur driving the thing

we obviously ran the car as it is supposed to be ran the 1st time, which brought our attention to the problem at hand atm.

removing everything meant we were able to find the source of the problem.

if u ran into a problem with everything attached, its impossible to find the problem.

its the process of elimination.

Edited by R34NRG
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thats exactly wat im thinkin. how f*kn weird huh? its bloody making 15psi of boost with a gaping hole in the manifold.

how do u explain that? other then the manifold is unable to flow air to the gate....

theres nothing Chinese on my car at all, although it would of saved me a ton of money....and everything is set up the same way as the tuner has done it with all his cars. but for some reason the added .5 of a litre is causing problems left right and centre.

Think of the manifold being really efficient at directing air to the turbine rather than being unable to flow air to the gate. Put a china manifold on and it'll hold boost but spool a fair bit later because the airflow is all over the place. The pressure inside the 6boost manifold will be lower, as the air is flowing smoothly and not 'bunching up', meaning the pressure difference between manifold and atmospheric will be lower than the cheaper manifolds, which makes boost control design important.

Extending the path to the wastegate, as you did first, placed more of a restriction there and made things worse. The extra half litre of displacement will, all else constant, increase airflow, again making things worse.

Holding 1 bar pressure while openly exposed to atmospheric is pretty impressive, the gas velocity would be up there.

Edited by govich
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the 'guage' reading the boost is a dyno-dynamics dyno thats sees way too many cars on it to not show up a faulty sensor like that

666DAN, yes, with a big gaping hole in the manifold, the car made 13psi @ ~5000rpm and was still steadily climbing

GeeTR, the new pickup for the wastegate is right under the turbo flange, sort of angled with the direction of flow, pointing up and off to the side of the turbo flange, and its on the very right side (looking at front of the car) that was the last time i saw it, i believe it was then blended in with the other one before the gate, but dunno whats happened since then

if the target boost is 20psi, from these figures, it looks like with the gate fitted it should be able to hold that. if not the next cheapest option is to run the gate off the exhaust housing. it is fairly common on really efficient set ups to do this.

p.s. although it doesn't look like it, this is actually a pretty good problem to have and means the potential of the set up looks good.

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it is useless, especially if the hole is still only 44mm wide.....which is why we made a 2nd WG port in the middle of the manifold that captures air from all cylinders. but still didnt work.

might have to machine the manifold and the 2 gates to possibly 60mm and use a 60mm gate

My turn to ask can you read posts properly :happy:

Putting a W/G at the base (middle/bottom) of the collector is almost useless, as it is directly opposite the flow of gases. What do you think is going to cause the gases to do a u-turn, of flow, and exit out the 2nd gate, instead of continuing on through the turbo. If a 2nd gate was required it should have been placed on the opposite side, of the collector, to the existing w/g, at the same angle.
Your new 2nd WG hole is useless not the 6boost hole/location.

Just a some food for thought:

Your set-up and Matt's (Yellow R33 GTST) setup are almost identical, except he is still using the 2.5ltr and you have a 3.0ltr, you both have a 6boost manifold and he even has the 90deg extension for the gate. Why isn't he having boost creep issues? The difference; he has a 0.8#a/r ext. housing on his GT3076R, you have the same ext housing on a bigger turbo that has a bigger ext. turbine. Is it starting to sink in now? Go to ATP, trade your ext. housing for a 1.0#a/r housing and your problems are solved, instead of spending twice as much on a 2nd WG or a bigger WG.

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My turn to ask can you read posts properly :happy:

Your new 2nd WG hole is useless not the 6boost hole/location.

Just a some food for thought:

Your set-up and Matt's (Yellow R33 GTST) setup are almost identical, except he is still using the 2.5ltr and you have a 3.0ltr, you both have a 6boost manifold and he even has the 90deg extension for the gate. Why isn't he having boost creep issues? The difference; he has a 0.8#a/r ext. housing on his GT3076R, you have the same ext housing on a bigger turbo that has a bigger ext. turbine. Is it starting to sink in now? Go to ATP, trade your ext. housing for a 1.0#a/r housing and your problems are solved, instead of spending twice as much on a 2nd WG or a bigger WG.

i wouldnt say it didnt do anything, it actually made the car a few 100 revs more responsive.

but i get ur point, and it makes sense. i was under the impression that matt was running a gt35 with a .82 housing aswell

but im curious about this exhaust housing exchange. how much does it cost?

Edited by R34NRG
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