m20 2.7 turbo conversion questions

[oakey]

after some advice on a turbo conversion for my 325isport with a 2.7 m20

I know pretty much F all about turbosHow much should i expect to pay for a good conversion?
How much power could i gain?
will it reduce the the life expectancy of the engine significantly?
Does anybody on here do turbo conversions?
thanks

[mattG]

depends on weather you use new or 2nd hand parts, how much power you want,

i would say 300bhp system new pro install has to be 5k min,

ive got most of my parts 2nd hand except a stand alone ecu that was pro installed and mapped by ant (A-tech tunning) and have spent 2k and still need some big injectors but i should get 260+bhp and even more torque at 7psi which should be reliable on std compression ratio

btw i know f all i'm just learning of these guys here

[Turbo-Brown]

Yeah, give Ant a tinkle having first decided what your goals are in terms of power output and also where you'd like your power to be.

Then see how much the conversion is gonna cost.

Doing it on a shoestring will either mean you don't reach your goals or that you can't go any further as your system's stretched to it's limit already.

I did all the work myself on mine and it came to around £4500 but I was pleased with the results I got.

Whereabouts you based out of interest Oakey?

[mattG]

mr brown you should come to a guilford meet some its not that far from you (only 10 mins fo me), love to meet the twins one day,

[Turbo-Brown]

I've been promising myself I'd come along to one since August or so. Think I might wait until the weather hots up a bit and the roads aren't so slippery though now, neither me or the car like the cold or going sideways at 50mph!

[mattG]

it's all about self control,

btw where did you get your oil-feed pipes from

[oakey]

thanks for the help guys
i live in surbiton surrey.
how much power is your twin turbo puttin out turbo brown?
sounds like it takes a fair bit of dollar then.
my car has just over 210 rwhp and 215lb/ft at the mo and i want at least another 30-40 hp.- is turboing the way to go? dya recon it would be possible to get much more extra power with some head work (bigger valves, high lift cam, springs etc)? anyone know how much power there is to be gained from fitting ITBs? what about superchargers?

[Turbo-Brown]

You really making 210bhp at the wheels?

If you are then there's a fair chance that your engine ain't gonna take kindly to forced induction as you must be running a pretty high CR and a fairly lairy cam? What have you done about injectors and management?

You might expect to gain another 10% on a good day from ITBs, but that's very ball park.

Mine's making 270bhp on 7psi.

btw where did you get your oil-feed pipes from

I machined up an ali block that bolted in place of the oil pressure switch and has 4 tappings, one of which accepts the switch again, the other three of which accept standard brake line fittings and take oil to the two turbos and the oil pressure gauge.

Then I made up a couple of adaptors to let me screw the brake line oil feeds into the turbos original oil inlets.

[mattG]

did i here you say you could make me one for a tenner

[Turbo-Brown]

Could make you one, but it'd cost more than a tenner

[gcorky]

alex-quick favour as im offline for a few weeks,when you get the h1c -the oil return probably wont be with the turbo...when you get one or make one.....bear me in mind and get me one...i adapted one but its not 100 %..

[Turbo-Brown]

No worries dude

[oakey]

I had a standard 2.7conversion done at bexleys nearly a year ago and it was dynod at just under 200hp. since then it has had a 272cam, polished and ported head, bored throttle body and another remap-dynod at 210hp
i think its running e36m3 injectors, using the standard management system.
Could i get more power with a standalone management system?
i dont have a clue what the CR is. (guessing its pretty high tho)
are you saying that there is not much more power to be gained if i leave it naturally aspirated?
thanks

[Ant]

standalone will release all the latent potential in there dude, on a stock 325 ( 170K miles) we saw 8% HP gain and 12% more torque everywhere, not just @ peak.

The AFM robs energy from the intake air, so loosing it is always a bonus, look at it this way, to go Turbo you'll need a standalone setup , so either way your next purchase should be a standalone of some kind, Unichip and MAF would also work but will be outgunned in the next round of mods if and when you decide to go F.I

bexleys 2.7 is normally 10.2:1CR , the effective CR will have been reduced by the extra overlap on your cam , as always there's room to move upwards but taking NA tuning to its zenith will have a retrograde effect on overall performance, peak power will move up the rev range, midrange torque will be lower.

[oakey]

thanks ant.
Do you fit standalone management systems?
How much should i expect to pay for a kit it fully installed?

The AFM robs energy from the intake air, so loosing it is always a bonus,

How do i do this? i gather i cannot just remove it?

[professormatt]

my 2.7 conversion has cost me so far £10000 just in parts,the only thing i didnt do was weld the head,this is the top end of the scale,but there are plenty of other turbo'd 2.7 done on a much cheaper budget,mine made 438bhp atw then the head cracked

[WillG]

were you using a MLS or orings?, oakey to remove the AFM you need standalone to be able to use the sensors that allow you to get rid of it i belive

[professormatt]

standard bmw head gasket with a o-ringed block

[WillG]

what do you think cause the crack, did you overheat, stock rev limit, gasket was ok?

[professormatt]

it was the 7500rpm limit,a first we thought it was the head gasket,pressure tested the head and found crack in one of the ehaust ports

[Turbo-Brown]

it was dynod at just under 200hp. since then it has had a 272cam, polished and ported head, bored throttle body and another remap-dynod at 210hp

You sure that's not a corrected figure for the output at the crank and not the power to the wheels?

[professormatt]

[quote="WillG"oakey to remove the AFM you need standalone to be able to use the sensors that allow you to get rid of it i belive[/quote]

sorry mate i didn't see this the first time

i'v used both setups piggy back and standalone, both do the job

the benefits using standalone is the abillty to map the car better low down in the rev range and naturaly right through out the rev range

i'v done away with the AFM (quick tip for you turbo boys still using the standard bmw AFM.grind off the rubber coating on small metal flap stop on the AFM.with age the rubber starts to deteriorate and gets sucked into the turbo,damaging the blades)

i now use a MAP sensor and a speed pick up on the crank

[oakey]

it was dynod at just under 200hp. since then it has had a 272cam, polished and ported head, bored throttle body and another remap-dynod at 210hp

You sure that's not a corrected figure for the output at the crank and not the power to the wheels?

Im pretty much positive mate. on the printout it says hp@Rwheels.
why you so suprised? when i first got the car i took it to bexleys and with no mods at all apart from a k&n filter(which probly hindered it) it was dynod at 164 at the wheels and after a remap it was 178 or sumink. thats about 210 at the crank isnt it?

[Jon_Bmw]

Pretty sure these are crank figures.

[Turbo-Brown]

Must admit I don't know much about the 2.7 conversion, but I do know that Bexley's made a 2.8 for a Zone member with all the bells and whistles including masses of head work, mappable engine management, ITBs and so the list goes on, and that made 260bhp at the crank so I'm surprised that your relatively mild spec is coming anywhere near that.

Also, it's my understanding that a decent 2.7 will make about 200bhp at the crank.