Turbo Specialists, Porting/modification/etc?

have a GT3582 here that i want to do some work to before i even think about fitting it.. anywhere good for porting turbine housings, opening up internal wastegate ports and maybe fettling with the compressor housing like drilling for anti-stall, etc?

Dan seriously. You havent even fitted the damn thing, so why the hell do you think you need anything done to damage it ?

And it would be a pretty odd 35 to have an internal w/g. Avoid !

already have the turbo stevie, i wanted an internal WG for handyness. rumour has it they are prone to boost creep tho.

i want it fettled beforehand because its a new turbo and all comes apart easy now, maybe not so easy once fitted and seen some use. theres a 3mm-ish lip on the T3 flange on the turbine inlet that can be ported or even chamferred, want to get rid of that lip and also open up the wastegate port as i measured it up and it can go out a fair wee bit.

on the compressor side.. i might fancy grinding down the bolts that hold the compressor housing to the central section as some of them stick out a little into the turbine housing on the inside, also maybe a gradual widening of the outlet of the turbine housing as theres a fair size of lip on it. i want to make all joins between pipes/hoses/intercooler/etc as smooth as possible, devils in the details for me here.. main thing is the turbine housing tho, could live with leaving the comp housing as is for now anyway.

few pics of the snail and some ideas marked up on the turbine housing/back plate or whatever u call it:



there is some method to my madness here..

When you see other people doing these things...maybe, and just maybe you can think they might be worthwhile.

But by sounds of things, you sure this isnt a cheap chinese copy you have ? From the way you describe it, it would be a horrific genuine part.

yea its a far east blower, how much money do u think i have? lol

manifold is also chinese but its been reinforced a bit as rumour has it they like to crack welds on the pipework due to the turbos weight and the pipes being thin-ish and welds not so great. also be heat wrapping it which should help slow the heat/cool cycles and help avoid welds cracking.

i have heard of people notching the rear cover on the turbine housing to allow the WG to open a little further, i will be doing that. also that lip on the T3 flange of the turbine housing has to go.. it annoys my happiness. and since id be getting that lip killed off i may as well have the WG port opened up a bit more.

its from a decent enough place, no excess shaft play or anything like that. id even stay away from the super cheap stuff ffs lol

Use it as is. Dont create problems before you even start ffs

Whats this for? Id hardly go to the effort if you're going to be running 6psi or some poo level of boost.

6psi? maybe for the first half hour its running before i start tuning it lol

up to 1 bar is handy enough on these engines so ill be running whatever i can before i start blowing out the spark on the old coil/dizzy ignition setup.

@ stevie, how would i create a problem just from port matching the turbine inlet and opening out the WG hole another 2-3mm? i have the time to do it now as theres other things need sorting before i can even bolt the turbo to the engine.

surely it would make a little bit of a difference all thrown together.. a 3mm lip sticking out the full way around facing right into the exhaust flow going into the turbo cant be a nice thing. opening the WG hole and notching the rear cover will hopefully be insurance against boost creep.

if i wanted to slap something together for as little as possible id chuck on some random little used turbo with a ghetto adaptor for the standard manifold and run without an intercooler. im building on a budget but i also want a setup that will see me running into spark blowout issues and making decent power but still with a bit of headroom to go later on if i want to ditch the standard ECU in favour of standalone or retrofit E36 M50 non vanos management and coil-on-plug ignition. shooting for something i can push further in future if i want to because everyone says boost is addictive lol

anyway sod the reasoning behind it.. where would be able to do this for me?

all wrapping the manifold will do is make it crack quicker.

Suppose it would be better for it to crack sooner than the paper and foil turbo to get ingested into the cylinders ! I don't think many turbo specialists would touch one of those tbh, be a bit like asking a hospital surgeon to have a look at a roadkill badger.

You seem to know so much about it.....do it yourself !! **** me, any idiot can do a bit of grinding.

Why the hell would you need anyone else to do it ???

You dont even have boost at the minute let alone boost creep ffs.

And you are doing just that by using a cheap crap chinese turbo. It might not even last long enough for you to get boost creep lol

i can't imagine how **** an internal wastegate would be on something that size. When I had a PROPER GT35, I had to use a 60mm wastgate.

Spark blowout issues? You do know you'll probably melt you engine before you blow a spark out? I fitted dizzyless ingnition to my Cosworth, know what differnce it made? None - and my boost peaked at around 35psi.

Also sounds like the turbo or manifold is poorly made if the flanges don't line up correctly, they should each be say a T4 flange and mate up perfectly.

the standard compression ratio on the M20B25 is around 8.8:1, hundreds if not more have hit the spark blowout wall on these engines.. its the main problem to be faced around 1 bar+. the only other issues is pushing out the standard headgasket if people half-ass it and dont bother changing gasket/studs as the stock bolts are stretch bolts. plenty of these engines fitted with nothing more than a fresh OEM gasket and ARP or metric blue studs and pushing 300whp+ across the pond.

the current record for an essentially standard M20B25 is at 647whp if memmory serves and the only supporting mods are milled OEM pistons to drop CR a little more, a turbo friendly cam and headgasket/studs.

yes the manifold is poorly made, they go for £130 new ffs but so long as it does the job then i dont really care. if i want to go all out later on i can always fit a decent manifold and better turbo later.

not trying to sound like a dick here but u dont see me telling u what to do with a sierra cosworth.. trust me when i say i know what these engines can handle.

I don't ask how to tune Cosworth engines as i leave it to somebody who knows how to

Why are stretch bolts an issue on your engine?

because with enough boost people reckon head will lift a bit and push the rings onthe gasket out. has happened to many people boosting these engines wihout bothering to change gasket/studs. mind u im not entirely sure if the head actually will lift or if most/all of those instances were just a rubbish tune or no tune at all and running an FMU. what really kills the OEM gaskets is a bad tune.

i know of one lad over in england who has seen 300bhp on an engine with nothing more than the head studs replaced with ARP one by one and actually leaving the original gasket in place, cant say how long that one lasted tho..

it may come as a shock but i actually do know how to tune BMW's M20/M30 engines and to a lesser extent some other E30 engines.. have sold countless chips and had my hand in 2 turbo builds on the ECU side of things (one an M42 turbo, another an M20 turbo) and had one guy actually bring a turbo 325i all the way up to me from dublin to get it mapped. also awaiting results on a chip i sent off to a spec class E30 racer in the USA for a dyno comparison with major names/brands. already had another spec racer do a comparison of an older version of my standard-ish engine M20 tune against a well known/long established brand name as well as against the standard tune. shall i post the graph?

All the above knowledge and skill...yet you still ask stupid bloody questions.

Do you ever take a step back and read some of the ***** you post ?

Ive said it before...keep gob shut, and just do it.

well im trying to just do it but no one seems to want to tell me where i can get what i want done ffs... never anyone mind why i want to do what i want to do. i want to fettle the turbine housing and thats that so where can i get to do this for me?

heres the last dyno comparo if anyone was wondering.. older version of my joe public aggressive M20B25 tune, FWIW i tuned it entirely on the street also but still managed to oust a major name in the mid range and only fell short in the high end by about 0.7whp. hoping the current version of that tune will yield a little more mid range as well as more top end but ill have to wait and see.

http://img546.imageshack.us/img546/2118/m20b25dmecomparison.jpg

dan son.. throw it at the car.... then fix what ever breaks.. time and time again un til it stops breaking..

simples

OK simple.

Bolts are too long ?? Let me think of a specialist who could shorten a bolt.....now that's a tricky one. I'll keep it a secret though

****ty Alu casting that needs a little ground off it....mmmm that's another hard one. Use a file perhaps ? carbide burr ? Really, how the hell is this difficult ?

And the w/g opening. Once again, another mind boggling thing to tackle. Maybe a shovel would be useful there ? A pitch fork ? or perhaps a grinding stone or carbide burr ?

Does someone else wake you up, dress you and feed you in the mornings ? or do you need a professional to do that too ?

I 'ported' my compressor housing and manifold with a carbide burr.