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Huge Boost Creep


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Often removing one of the springs in the 1 bar gates helps, as does a change of cam timing, and also putting a proper cat in, the back pressure reduces boost. Simply put, if you want to run your car like a race car with a 3.5"+ exhaust, no cat and 1 muffler, then run a race style 50-60mm gate, don't expect to use the best manifold on the market thats is designed to stop turbulence, reversion and increase velocity, and expect to use a street style(for the application) 40-45mm gate.

6BOOST

i understand wat your saying about the 1bar gates and removing the spring, but it dosnt matter if the manifold is boostspiking with NO GATE at all. spring or no spring it aint gonna make a diff.

but its interesting that u only now mention a 60mm gate. i remember calln u and askn if a 44mm gate would be sufficiate enoguh for my setup. my tuner said it was, you said it, even other setups list a 44mm gate.

and all of a sudden the issue pops up and the answer is a 60mm gate.

modified the manifold for dual ports, cut the wastegate port off, and running with no gate. still overboosting. but it taps off at around 10psi and slows down to 13psi. which is alot better then before.

f*kn dont know wat to do anymore

apart from gettn a whole new manifold (which is bs) and a new 60mm gate (which is even more bs cuz we dont know if it will fix the problem)

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I may be way wrong here as I play with smaller 4 cylinder engines that don't run split pulse housings. But when i look at the picture of where the WG piping comes off it looks as though it only comes off only one side if the split collector meaning that the other side is still being fed by 3 cylinders which are ungated?

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I may be way wrong here as I play with smaller 4 cylinder engines that don't run split pulse housings. But when i look at the picture of where the WG piping comes off it looks as though it only comes off only one side if the split collector meaning that the other side is still being fed by 3 cylinders which are ungated?

i dont believe he runs a split pulse turbo.

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You've been told how to fix it, yet your still here posting dribble?

for the love of god...

modified the manifold for dual ports, cut the wastegate port off, and running with no gate. still overboosting. but it taps off at around 10psi and slows down to 13psi. which is alot better then before.

are u f*kn seriously just tryna piss me of off ash? or u clearly jsut cannot read?

gtfo.........u aint got nothing useful to say

I may be way wrong here as I play with smaller 4 cylinder engines that don't run split pulse housings. But when i look at the picture of where the WG piping comes off it looks as though it only comes off only one side if the split collector meaning that the other side is still being fed by 3 cylinders which are ungated?

its not split pulse

and yes u are right the wastegate port is one sided, which is why we made a 2nd wastegate port in the middle of the manifold so it gets air from all sides. Which then murges back before the wastegate.

but still over spikes.

i dont believe he runs a split pulse turbo.

no i dont =[

Edited by R34NRG
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I think you should stop posting dribble, and take it off the forum.

Your not doing yourself any favours coming out and trying to get stuck into the manufacturer of the goods and having a good ole e-war with him.

Hardly tactful, hardly smart.

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No offence taken, however to highlight the points you just raised, my gate outlet comes off the collector at 30deg, I cut every single one of them and put in a big box with my drop saw every few weeks, so I know the angle, maybe you haven't taken notice before. Secondly to that, the gate outlet pipe is 42mm id. A Tial 44mm gate(most common I and my customers seem to use) is measured at the valve, not the hole in the inlet, which is actually around 41mm or the same as the outlet pipe. The other most common gate is the turbosmart 48mm, which as a 45mm hole in the inlet flange, again, only 1.5mm per side bigger than the pipe I use, there is no such thing as 50mm pipe. Conversly, the next size up pipe has a diameter of 54-55mm ID, its so big that the gates we are talking about, the flange would fit INSIDE the gate outlet. This in my eyes would cause massive turbulence into the gate... Would the bigger outlet pipe make up for any downsides to the flange transition?? I don't know.

Simple fact is, if anyone has a probem with boost control, calls me, and actually listens to what I have to say, rather than just look for someone to blame, rarely can you not get a workable result easily. Its just most people want to listen to the advise of others, rather than the designer of the product who has done over 1000 manifolds and encountered every problem first hand along the way. Often removing one of the springs in the 1 bar gates helps, as does a change of cam timing, and also putting a proper cat in, the back pressure reduces boost. Simply put, if you want to run your car like a race car with a 3.5"+ exhaust, no cat and 1 muffler, then run a race style 50-60mm gate, don't expect to use the best manifold on the market thats is designed to stop turbulence, reversion and increase velocity, and expect to use a street style(for the application) 40-45mm gate.

6BOOST

my manifold came out at a 90deg angle to the flow, split pulse 90 degree t4 flange... i can run the lowest of 15psi on a tial 44mm and it creeps to 18psi, holds flat if boost controller is set to that and i dont mind because the motor can take it but if i wanted to run less boost i would have problems

another t3 flanged manifold we ordered you are correct it did come at a angle but we wanted to run a 60mm gate so we welded on a bigger pipe at the same angle as the original and works very well. it must have been a 54mm not 50mm my appologies, we have ordered the most recent one with no gate pipe at all. can you possibly make a option for people to have the bigger pipe when ordering?!?

as i said they are great manifolds and i recommend them to everyone, just trying to give you some feedback on my experiences

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Had a chat to my mechanic and Andriano is partly right.

Even though i have a similar setup, with the same size ext housing on the turbo, you are running a bigger hp turbo, thus having a bigger ext wheel. The bigger wheel in the same size housing will not allow enough air to flow past through the housing without spinning the wheel faster and faster.

Two options: Upgrade to a 1.06a/r ext housing, will also give you better top end, or "bleed off" more gases (ie: larger feed to gate and larger gate or run 2 gates)

Either way not really the "fault" of the manifold design

Has anyone at R.E. rang any turbo experts (ATP, GCG, etc) to discuss the above mentioned probability, before hacking the manifold? They may have agreed that such a efficient set-up (manifold, exhaust, etc) will cause the turbo to keep boosting due to the smaller ext. housing and large ext. wheel of the turbo.

Putting a W/G at the base of the collecter 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.

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Putting a W/G at the base of the collecter 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.

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

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i understand wat your saying about the 1bar gates and removing the spring, but it dosnt matter if the manifold is boostspiking with NO GATE at all. spring or no spring it aint gonna make a diff.

but its interesting that u only now mention a 60mm gate. i remember calln u and askn if a 44mm gate would be sufficiate enoguh for my setup. my tuner said it was, you said it, even other setups list a 44mm gate.

and all of a sudden the issue pops up and the answer is a 60mm gate.

modified the manifold for dual ports, cut the wastegate port off, and running with no gate. still overboosting. but it taps off at around 10psi and slows down to 13psi. which is alot better then before.

f*kn dont know wat to do anymore

apart from gettn a whole new manifold (which is bs) and a new 60mm gate (which is even more bs cuz we dont know if it will fix the problem)

the answer is not a 60mm gate, it is having the 44mm the right distance from the manifold as per kyles design.

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I would have thought the best way around this problem is to run the wastegate off the exhaust housing, as it should allow a better merge angle, but obviously space constraints may prevent this

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Dood, make sure the WG piston is free to travel...take the spring out and physically pull the centre of the diaphragm... it should travel atleast 10mm...make sure the stem is not damaged...also make sure the diaphragm itself doesnt have a hole in it as well...connect a tube to the bottom port and blow into it and listen for leaks...apologies if this has already been covered...

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the answer is not a 60mm gate, it is having the 44mm the right distance from the manifold as per kyles design.

unfortunately its not. we chopped the port off complete so its running straight from the manifold.

it did help....but still overboosting by 10psi......which i guess is livable....but still shouldnt be happening....and i dont want it happening

I would have thought the best way around this problem is to run the wastegate off the exhaust housing, as it should allow a better merge angle, but obviously space constraints may prevent this

but i shouldnt need do. theres 1500hp cars out there running a gate off a manifold with no issues at all, why the hell should i need to do it.

and its a shit way of doing things, to messy and no room. basicly it feels backyardish

Dood, make sure the WG piston is free to travel...take the spring out and physically pull the centre of the diaphragm... it should travel atleast 10mm...make sure the stem is not damaged...also make sure the diaphragm itself doesnt have a hole in it as well...connect a tube to the bottom port and blow into it and listen for leaks...apologies if this has already been covered...

its alright buddy, and it has

the manifold with no wg at all, with a big gapping hole is still over boosting, so even if i did put the wasstegate back on, checked the spring and everything.

it wont change anything

the manifold is not bleeding enough air quickly enough to the gate....for the gate to do its job.

it has nothing to do with the gate.

its simply the manifold.

the question now is how to get the manifold to flow enough, whether it be slammin the gate onto the exhaust housing, makn the wg port bigger on the manifold or dual porting it.

which i have tried all except the exhaust housing one(which i dont want to) and have all failed.

im thinking about possibly increasing the size of the dual ports.....and seeing how that goes.....

Edited by R34NRG
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its alright buddy, and it has

the manifold with no wg at all, with a big gapping hole is still over boosting, so even if i did put the wasstegate back on, checked the spring and everything.

it wont change anything

the manifold is not bleeding enough air quickly enough to the gate....for the gate to do its job.

it has nothing to do with the gate.

its simply the manifold.

the question now is how to get the manifold to flow enough, whether it be slammin the gate onto the exhaust housing, makn the wg port bigger on the manifold or dual porting it.

which i have tried all except the exhaust housing one(which i dont want to) and have all failed.

Shit...never heard of anything like that before....when you start the engine with the WG off does it feel like you are getting a lot of exhaust flow out of the WG flange...(just wondering if they may have f**ked up somewhere in the fabrication. ie not drilled where the WG pipe is welded onto the manifold...remote possibility but you never know...

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Shit...never heard of anything like that before....when you start the engine with the WG off does it feel like you are getting a lot of exhaust flow out of the WG flange...(just wondering if they may have f**ked up somewhere in the fabrication. ie not drilled where the WG pipe is welded onto the manifold...remote possibility but you never know...

the manifold was designed with the wg port on one side.....which was a lil weird because it looked like it was only able to get air from one side.

which is why we made another one in the centre that catches from all sides, that merges back later

previously boost wen spiking over 15psi and still climbing with no end.

but now its taping off at around 10psi and then holds at around 13psi. which is okai but id rather see it down around 5psi.

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just some reading i've done has shown up another RB30DET, running the same gate, same turbo, in general a very similar setup, only major diff is the manifold. this car holds 11psi, and keeps it there. car runs standard cams etc too i think

and andrews car is running 3" catback exhaust . surely you would not expect anything more restrictive than that? *no cat apparently*

gate will not be welded to the exhaust housing, its just not happenening.

Edited by VB-
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do a careful dyno plot with the wastegate disconnected, the vac line

this will mean unlimited boost (almost like how it is now) so dont trash it on the street, dyno only

a great way to kill your engine is by stuffing around with the boost on a fresh new engine

if you get the same result, either the vac signal to the gate is incorrect or the gate isnt working correctly

how much boost do you want to run ?

we plannin to run 20psi for a start.....not sure how high we willl go

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.

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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.

no no no, i dont want to run 5psi. i want the manifold to hold a max of 5psi with no gate. because we already identified that it was the manifold that isnt able to bleed off enough gas to the gate, which creates infinite boost.

with the gate on and and set to .9bar from the wastegate, it made 15psi at 4000rpm and kept rising. you could tell by the boost cruve that it would kept on going, even past 20.

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