Jump to content
SAU Community

Recommended Posts

all of this on a stock bottom end?

I'm running 14psi.. Tuner says there is a big difference between 14 and 19 psi, and like 50rwkw worth, but there is also a difference in the bottom end staying together and going bang...

Got me scared...

  • Replies 333
  • Created
  • Last Reply

Top Posters In This Topic

well, I have a heap of logs that you can analyse.

All recorded in datalogit, and easy as

Open FC-Datalogit

Window

Mapwatch

File-> Open

Select one of the log files

Log_20051219_1747.txt

Log_20051219_1752.txt

Log_20051219_1756.txt

Log_20051219_1757.txt

Log_20051219_1758.txt

Log_20051219_1759.txt

Log_20051219_1801.txt

Log_20051219_1805.txt

all of this on a stock bottom end?

I'm running 14psi.. Tuner says there is a big difference between 14 and 19 psi, and like 50rwkw worth, but there is also a difference in the bottom end staying together and going bang...

Got me scared...

I wouldn't worry too much - it's not so much the boost that kills engines it's pinging. It'd be interesting to back off the timing a bit, make sure the AFR's are right and do a few power runs with more boost.

You'll definately have to run more boost if you want to make some decent power - there's a bloke on these forums with a gt30 internal wastegate on a rb25 - I think the one with the small rb exhaust housing who was making over 250rwkw with the stock bottom end. (horsepower in a box kit)

Now he's installed cams and is making more - all depends on whether you want to take the risk - if mine goes bang I'll go a rb30 bottom end.

My adjustable nismo FPR is set at 45 psi at idle.

How does the car drive? Does it feel faster than when it had the stock turbo?

Maybe the dyno wasn't reading right?

Cheers

well, the car drives ok...its very laggy. Doesn't come on hard until 4000rpm, which I am not impressed about.

Its a Stock sized ex housing for hells sake!

I don't really know.

Car pulls A LOT harder up top, as the dyno figure shows 460nm of torque or about that. I don't have the chart because the tuner reckons his printer is buggered. I think his whole set up including him is buggered....

I thought I posted again but it must have got lost .

That TO4S wheel is probably not helping much but the GT30 turbine in a non native VG30 housing is almost certainly causing some restriction . That housing was intended for a much smaller ceramic turbine and in low boost form (7-8lbs?) good for 190Kw on a 3L V6 . I know the high flow makes more but its 76T XXXX turbine is of lower tip height than the 84T GT30 and somehow works . Its 71mm XXXX compressor is smaller than the 76mm TSO4 so it is better matched to its turbine . Actually for its age its compressor is quite efficient .

I can't emphasize enough that its the TURBINE/housing combination that drives a turbocharger . The best car in the world is stuffed if the engine is a dog and the same is true for turbos if the turbine/housing combination is not sorted . This is always the hardest part to get right and often OEM mounting flange / integral gate convienence brings it all undone . This is why firms like HKS go to the trouble of making model specific kits that bolt on . Yes its expensive but it BOLTS in reasonably quickly and easily and is generally a known quantity . Mafia , I dare say you found out the cost of many fiddly one off bits adds up to a tidy sum and on top of the turbo price could be reaching up to that of a complete kit . I think you're choices are limited to fitting an exhaust housing that works or changing the turbo for something more suitable .

At the end of the day even if you can get around the detonation dramas its doubtfull if it will reach your power goals . It sounds like the exhaust restriction is causing heat probs within and detonation . An easy way to find out is to connect your boost gauge to somewhere on the engine side of the turbo (exhaust manifold or turbine housing before the turbine) and check the pressure . Don't be surprised if its double or triple that of you're inlet manifold pressure under boost . Waste gates generally "blow open " because exhaust manifold (turbine inlet) pressure is much higher than boost pressure . If you have three + times the boost pressure acting on the flap valve and one times boost pressure acting on the actuator I know who's going to win every time .

Out of time again , cheers A .

Before I give my opinion on that we need to know what the original goals were .

Where you wanted it to go from and how much top end .

For fast road you probably want it to go from ~32-3300 rpm and have good mid range torque .

GT30 turbines really need GT30 turbine housings to work properly - the nossle area of the housing needs to suit the exducer tips of the turbine blades . Garrett make turbine housings to suit in .63 / .82 / and 1.06A/R - external gate T3 flanged . As far as I know only HKS make propper integral gate GT30 T3 flange turbine housings that work . These are intended for HKS's bolt on version of the real GT30R , they call it GT3037 Pro S but it uses the identical cartridge (700177-7) as the real GT30R (unit no 700382-12) does .

I think you have 4 choices here as usual based on cost .

1) Buy and fit the HKS Pro S integral gate housing in .68 or .87 , it would need

the HKS or copy dump pipe to suit .

2) Buy/fit the HKS cast manifold and external gate and use a Garrett housing .

3) Buy/fit HKS 2835Pro S or 3037Pro S kit .

4) Get your original turbo Hi flowed and fit it back in with the standard fittings .

People say it works well with the VG30 housing but you'll need another as your

one is machined out differently but check it out anyway .

I found out the hard way years ago that expensive one off bits are a pain because they only suit one combination and if it doesn't work the doughs already spent .

Yours is an easy situation to get into and an expensive one to get out of - how expensive will depend on what you can sell the bits you don't want for .

Can the moderators make this a STICKY . Buy Garrett Ball Bearing turbos with 7 bladed TO4S compressors at your own risk . Nothing about these compressors is desirable and the results are bad . A propper version will have GT (Garrett Technology) turbine AND compressor and an "R" or rolling element ball bearing cartridge . The turbine housing should be a match with the turbine in one of the available A/R's .

Mafia - I had a VG30 rear housing into a rx7 core and rear wheel with a .60 at t4 front and the max power i was able to get was about 240rwkw.

The rear housing would get extreamly hot and it was just detonating on that power. We tuned it down to about 225 or so rwkw and it settled down a fair bit - this was on a rb30det.

Boost would come on at 1800rpm to 2100rpm and would fall off up top big time.

The VG30 rear housing is a good upgrade for the stock turbo but its not going to bag you alot of KW. (apparently they are .71 but when you start grinding them out to put a bigger wheel in them the AR ratio gets smaller and it becomes restrictive) i had to keep the boost at 9 or 10 psi to stop detonation and make the power - used lots of timing.

I have sold my turbo to a guy who has a relitivly stock car and got a top mount manifold and a GT3540 with ext gate. Car is not finished yet but it may be done by the end of the week.

Since the 230rwkw with vg30 housing i have got

forward facing plenum mod

top mount (ebay special with 10 hours spent on it to get it acceptable)

gt3540 .82 rear housing 70 front

genuine tial wastegate

Nismo 740cc injectors

Q45 AFM

300x600x100 fmic

Il let you know how i go with it once its going - but im expecting at least 300rwkw or more.

Man, this is a sad story about a mod that should have been THE duck's guts with the effort you've gone to.

discopotato03 given that these guys have both done a hybrid using VG30 housings and both ended up with what appears to be a choke in the turbine area due to the flow capacity of their compressors, can you see what similarity they have in the CHRA?

hhmm... Just thinking, I have a few ideas to try and make this a little better.

First I am gonig to install a spring on the wastegate flap to try and create a bit more tention, to see if its blowing open.

Second, I am going to do what I have been meaning to do for a while and get a better boost controller than a bleed valve - The powerFC boost control kit. My mate set up the Link boost control kit and his boost was hitting way harder, and much better and earlier. You could even hear the turbo work a lot harder.

The exhaust housing: Do you all think I should get the garrett equavilent .63 internal gate housing, or go a step bigger and get the .86 internal garret housing?

I'm a little confused. Will the specs of the turbo help? I'm going to get them and post them up

Edited by The Mafia

try pricing a HKS exhaust housing from greenline.jp or racetep.com

ps. Precision Turbos in the USA apparently also make internally gated GT30 exhaust housings.

Edited by wolverine

I'm not going to mess around with the VG30 now that I've seen a few have issues making close to 270-280rwkw.

GT30R + .87 HKS Turbine housing + HKS Cast manifold is my decision... for now lol.

I'll be happy with 270-280rwkw, more than enough in rwd 1300kg 3ltr mid range monster. :blink:

The GT35R would be nice BUT with the .82 it appears with cams its pretty much all in by 3500rpm. I really want it in by low 3000's.

Even if the HKS turbine housing ends up costing as much as an external gate setup I don't care, I want it looking stockish with a decent manifold (HKS Cast) and without a manifold and external gate hanging out everywhere.

Such a Pitty HKS didn't place the external gate flange underneath instead of on top.

Edited by Cubes

Ok Mafia has given me the numbers he's seen on the ID tag fitted to the core of this turbo unit.

He's read it as 700177-5011

Looking at available literature, I suspect it will actually be 700177-0011

check this site which gives specs:

http://www.turbomaster.info/eng/applications/bearings.php

For that CHRA number, it should therefore have

Compressor 76mm T04S, 55mm inducer, 52 trim

Turbine 57mm GT28, 54mm exducer, 90 trim

As previously noted, he has a 0.7A/R comp cover. Not sure of the specs on the cover (read: nozzle/tail sizes), but it clearly has a bloody big bell-mouth.

Hot side is the VG30 housing for which there have been a number of "guesstimates" on the A/R. Fact: nobody's (on this board that I'm aware of)actually sectioned either a VG30 housing or one from a RB20, 25, 25 Neo, so the A/R of each is not known. It does seem fair to say that the VG30 IS larger, but by how much we don't kow.

What would be worth knowing is whether anybody has easy access to a VG30 or 25 Neo unit so that they can accurately measure (using verniers) the size of the turbine impeller at the inducer and exducer. A reasonable computation of the wheel size can be made (max diameter + trim) so we can at least see what was matched by the engineers to that housing.

Until that is known I would not like to draw any conclusions or make assumptions about flow restrictions with Mafia's combination (even if they may be correct). :)

cheers

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • So, I started this repair and got as far as "fixing" the holes with some fibreglass. God all those years working on boats came back quickly. I decided I'd reach out to some rust guys just to see what they would say about it. I came across a guy about 40 mins away and went to see him. He said the windscreen needs to come out, that there might be some more bits around the windscreen and he'd quote them at the time. But his quote was $300 to remove and replace windscreen and $3k for the damage he can see. He said he could respray the roof for $1200 and the bonnet for another $800 (somebody has previously rattle canned it, its horrendous). This is $5300 + any small additional bits. It's a lot, I get that and the name of one of my fave youtube channels 'Not Economically Viable' comes to mind.  I'm not being financially rational, but I've taken him up on the quote. He's opening a new shop in November with more room, so we're waiting for that. I'll leave the currently missing headliner out until then. I'm looking forward to it being fixed and having the paint looking nice again (lots of clear coat issues on the roof too). / flame suit on.
    • Oh and some up-and-comings; New rear drivers wheel bearing. I'll do that this weekend while the diff is out. The car is already up and the d/c axles and missing exhaust will help with space. This is the last bearing for me to do and I've been dragging my feet on it. I also have some new EBC blue stuff pads for the car and some new brake fluid. I haven't ever flushed the fluid in this car and looking forward to it. I have 600 degree fluid to put in. Not exactly "race fluid" but better than the typical stuff I have been using.
    • A proper clutch/plate type mechanical diff with quite a lot of pre-load and high locking % is better for drifting. Much more consistent in its behaviour. A helical can be annoyingly vague and inconsistent in how it responds under the sorts of abuse found in drifting.
    • Some updates here. I pulled the entire interior out, minus some trim to respray the seats with Colourlock dye. It turned out really nice though I accidentally let the dog in the car after and she scratched up the front seat.  This is what it looked like before, the colour was just washing out everywhere but thankfully the leather was in good nic. Then after the respray   And after the bloody dog jumped in The headliner is out waiting to be retrimmed, but it will stay out now until Nov - see why below. I replaced the stereo/headunit with a period-styled Android headunit. I have no after pics, but I'll get some. This is because of the missing pixels. I tried to fix this twice with replacement ribbon cables but couldn't. Also the bluetooth interface I'd bought for this was crap. Then there's the rusty roof. Pics and info in this other thread. I have decided to get this repaired professionally, but I'll update that thread. This is why the headliner will stay out for now. I'll be getting the roof and bonnet resprayed at the same time the rust is fixed. I also had an interesting issue with my drivers door lock.  For a small period I was having issues getting any 12v power to the car - I mean *any*. It would have no dash lights, nothing. It happened while I was at the shops and I couldn't get in the car. So, we had 2 problems. The most pressing here is that I was locked out. I have only a single physical key hole on the car, the drivers door and no amount of turning would unlock the car. Surely it doesn't need power for this? The second issue is why am I losing all power periodically, The battery isn't dead, its almost like the battery isn't even there. Two issues that were surprisingly easy to fix. You fellow BMW over-engineering lovers will appreciate this. The lock in the door has 5 states; mechanical lock, electric lock, neutral, electric unlock, mechanical unlock achieved at -90 degrees, -45 degrees, 0 degrees, 45 degrees and 90 degrees. Although, the unlock is towards the front of the car, so opposite for LHD countries. Sticking the key in and turning 45 left or right is what is used 99% of the time. It activates the central locking etc. 90 degrees is for dead battery access and, obvs, only un/locks the one door. But because the mechanical lock is never used and is 27 years old, it seizes up. I was totally unable to turn the key far enough to get to the mechanical unlock (At the time of locking myself out, I didn't even know this was a thing). I eventually did it with some vicegrips and teflon spray.  I made a quick vid for other E39 peeps.   The battery issue is totally new to me also - It wasn't making sufficient contact between the post and the terminal. The terminal was bolted on tight, but the car wouldn't have power. After checking the battery with my multimeter I accidentally contacted the terminal and the battery post and the car got power. The battery was only a few years old and in good condition. I cleaned the post and the terminal with a wire brush, bolted it back on tight and never had the issue again. I'm still surprised that despite having solid contact it didn't work. Also, the car was getting Warragamba sized pools of water in the back when it rained. My initial concern was another rust problem. But when I went out on Weds while it was raining and while I had no headliner in I could see a steady stream of water coming through the roof mounted aerial. As this aerial is for the (now removed) car phone I pulled it out and whacked a blanking grommet in the hole. It seems fine now. I'm thinking I might get the hole permanently filled when the rust is fixed. Moving forward and things in progress; The tailgate needs some attention. I have taken all the trim off to clean it all and address some small rust spots. I have partially done all of this but I'll finish it up hopefully this weekend. As all the trim are now entirely devoid of trim clips I have bought a heap of strong velcro and I'm hoping it does a good enough job as any of this trim in good condition is super expensive and usually in Europe as we dont have many of the wagons here. Suspension and brakes!!! This is exciting. In the front; New control arms New sway bar links New lower Eibach springs (the only modification I'm planning on this car) M Sport shocks (these came with the car and will replace the longer shocks in the car) New top mounts Used 540i calipers (stock brakes suck!) New 540i disks and pads (22x296 mm for 528 and 30x334 mm for 540i) New front wheel bearings (thank all that is holy for bolt on bearings!) Annnnd in the back; New control arms New sway bar links Adjustable air suspension arms (fool the car into what the current height is so the self levelling suspension can match the new front ride height) New ball joints I'll also be doing a brake fluid flush while I'm in there. I'm planning on switching the car over to the 16's that came with it so I can clean up and respray the M Sport 17's. They've lost a lot of colour over the years and have some gutter rash. None of this will start until the E90 is back.
    • You mean you will regret it for drifting duties? I don't quite follow.
×
×
  • Create New...