E30 Zone

Hi
just been playing around on ebay and found a company that is selling
a turbo kit for the m20 engine!!
Turbo looks small to me?
Whats your view!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Link????

forgot link go to ebay and type in 120125389778

Slowwwwwww

if it's a t3 then it'll be capable of 300bhp without too much trouble. it's only a low blow (8psi) kit anyway, much more would mean needing other mods like lowering compression, forged pistons etc.

maxfield wrote:Slowwwwwww

lol! Indeed

So harry with this kit i could bolt it on and expect good gains??
without new lower compression pistons etc

Which engine have you got?

If it's a late 2.5 engine, it'll have a nice low compression ratio as it is and will soak up more than 8psi without any problems.

T3 will not do 300hp on the 325

no way, no day, 250 lbs/ft or torque and 230 hp maybe, been there , done that, waaaaaay too small for the claimed power gains, nice torquey conversion maybe yes.

to be blunt, for the price of the complete kit, you'd only get a gen garret turbo and the oil feed kit in the UK, says something about the quality no ?

why doesnt the t3 manage 300 bhp on the m20? it does up to 330 on a cosworth.is it to do with being 6 pots and 4 pots or something completely different?

is it to do with being 6 pots and 4 pots or something completely different?

If it is just fit 2

So if you had the money and all the other mods.
Six branch high lift cam chip etc would this be a good kit to go at a reasonable cost? or does it look dodgey when reading specs.

fuzzy wrote:why doesnt the t3 manage 300 bhp on the m20? it does up to 330 on a cosworth.is it to do with being 6 pots and 4 pots or something completely different?

Might be becuase that the cossy has a 4 valve per cylinder setup.

the 6 cylinder has 2 extra pulses per crank cycle, and displaces an extra 500cc ( B25 obv ) so when compare to a 2 litre 4 pot, you can see why its too small no ?

lots of torque ( mine had 213.9 lbs/ft @ 1809 rpms) but wont make the claimed figures.

i dont understand

surely the aif flow needed for 300bhp is going to be pretty similar no matter what the engine, t3s are fine for 300bhp plus on loads of other cars

Ant wrote:the 6 cylinder has 2 extra pulses per crank cycle, and displaces an extra 500cc ( B25 obv ) so when compare to a 2 litre 4 pot, you can see why its too small no ?

lots of torque ( mine had 213.9 lbs/ft @ 1809 rpms) but wont make the claimed figures.

no,im afraid i still dont understand

Surely a T3 on a 6 pot has to work 50% harder than on a 4 pot?

d6dph wrote:Surely a T3 on a 6 pot has to work 50% harder than on a 4 pot?

even if its to give the same amount of end power? isnt that down to fueling?you need a certain amount of fuel and air to mix and give 330 bhp in the 4 pot. wont that same amount of fuel and air be nessesary in the 6 pot but spread between 6 injectors instead of 4?

fuzzy wrote:

d6dph wrote:Surely a T3 on a 6 pot has to work 50% harder than on a 4 pot?

even if its to give the same amount of end power? isnt that down to fueling?you need a certain amount of fuel and air to mix and give 330 bhp in the 4 pot. wont that same amount of fuel and air be nessesary in the 6 pot but spread between 6 injectors instead of 4?

Its not just the extra 2 cylinders, but the extra 500cc........

A 2.5 needs more air than 2.0

Kam is correct, you have an extra 500cc of capacity per revolution of the engine with the m20b25 than you do with the cossie, which means that it needs more air per revolution, which means that you need a bigger turbo to get 300bhp out of an m20b25 that you do a 2.0 YB engine, as it needs to supply more air per revolution in order to get the same amount of power

billgatese30 wrote:Kam is correct, you have an extra 500cc of capacity per revolution of the engine with the m20b25 than you do with the cossie, which means that it needs more air per revolution, which means that you need a bigger turbo to get 300bhp out of an m20b25 that you do a 2.0 YB engine, as it needs to supply more air per revolution in order to get the same amount of power

i think its finally starting to sink in now and its starting to make sense to me

surely a comparrison between the compression ratios would put this to bed?

Cr is irrelevant

ok, lets break it down...

2 litre 4 cyl = T3

2 litre 6 cylinder will need a turbo with(approx) 50% more flow on the hotside( turbine) to make the same power as the 2 L4( given the same compressor trim and A/R ), why ? well, simply put, the two extra power pulses will effectivly overdrive the turbo, leading to earlier spool up, and monster torque , but less outright BHP as it will restrict flow beyond peak torque.

now, apply the same thinking to the B25, and you should see WHY its too small to make the claimed power figures...

If a T3 on a 6 pot gets the turbo going quicker with more torque would this not make a more drivable car than say T4/5 giving more bhp? So what you mean as the turbo is getting peak boost earlier, past peak torque the turbo cannot supply enough air beyond this even by upping the boost pressure the volume of air supplied is still not enough to make significant gains in power?

Indeed, the car will be very streetable.

my car was T3 equipped( as stated in this very thread) great torque, zero lag and all that Jazz.

more boost pressur eon a small turbo will result in severe Det and engine damage

Turbos are a pump, the ratio of pump to engine capacity and layout is the key to getting the best outa a turbo setup.

the case in point here is, that pump is too small to feed an M20 over 4.5K with anything but the exhaust gas left over from the last crank revoloution( because most remained in the cylinder due to excess backpressure from the small hotside and turbine assy)

You can use a T3 hotside, but it requires the biggest trim wheel in a havily modded 0.63 A/R hotside housing with at least a 60mm trim compressor wheel in a 0.60 housing, that will make 300HP and still give monster midrange torque.

I'm talking from experience here guys, take it or leave it

From your experience Ant if a hybrid T3 can make 300bhp what sort of psi would it need to pump compaired to a more generic larger turbo say T4 or whatever you would recommend? Also why is det a problem on these engines do they not take kindly to decent amound of boost 14psi +?

dude, 10psi is 10 psi, the key is getting peak boost after peak N/A torque, then the engine will breathe as its maker intended and give the power.

more boost doen't mean more HP, in many cases where the compressor is too small, the compressor will be out of its efficicnt range and pumping a lot of heat into the charge pipes, not good for power or longevity.

Det is a problem in any engine, the M20 is no more or less prone than any other

if you want high HP then a big snail is required, or two small ones as per Turbo Brown and Bootyman.

as for Recommendations, NOTHING off the shelf will work that well, a hybrid of some sorts will always be required.

I have T34/35/38 hybrids made to order( my spec) to suit the 300 HP goal, and use Holsets( again hybids) to go higher HP as they're simply the most advanced and efficient Turbos on the market today, although Garret are catching up with the revisesd RB-GT series

woohoo i understand something technical and bmw orientated!

So whats required for a reliable, streetable 350bhp at the crank (or at least 300bhp at the wheels)?

Low comp internals, MS, big snail and some A-Tech magic?

A-Tech magic

What about a 2.0litre m20, what modifications after this kit would have to be made?

aw ant man ive only got a t3 now im dreading the day it hits the roller, prob only be pushing measly figures. lol