No they werent. They were invented to run intake manifolds at pressures above 1 bar absolute with ease to increase an engines VE without having to resort to displacement increase.

Pressure and flow is NOT a linear calculation any any size transfer vessel.

Any further thought on my previous comprehensive reply?

 

Its all about pressure drops Lee.


Thats why i said on the other forum about you measuring the boost at the manifold and at the turbo (or was it on hear, i dont remember )

That 1.2 at the inlet might be 2bar + at the turbo!


I cant comment on those other engiens as i havent worked on them so it would be guessing, they could be ported manifolds etc for example.

 

Indeed, hence my compressor map comment...

 

Indeed, all too easy to think you are on the map about a bar absolute from where you really are!

 

yes thx stu.

1.) it is assumed that the manifold will flow upto 600bhp and the turbo hotside 450bhp . not assumed just what has been done before. and the turbo is rated at that flow

2.) will investigate . possibilty

3.) if i have a restriction i can increase pressure to increase volume (obviuosly until the on slaught of det?)

4.) at 1.2bar its nowhere near off the compressor map/ temps <40degs

5.) its not laggier than expected but still could be possibility

thx

 

See out points above mate.

That 1.2bar in the manifold could be eleventy seven psi at the turbo.

 

hmmm interesting about the boost pressure exactly as it exits the turbo . will test.

 

Its actually quite incredible wheny ou look through my reports that only about 1 in 20 cars in for mapping actually manage to get through the first test. Leakage. We normally have masses of leaks from 1 bar onwards. People dont realise how much presure 1 bar actually is on a shonky jubillee clip, or, in a case last week, some wire tied round the joint like a belt.. yes, a cossie running 30psi.

 

By probing different points in the inlet, you can see where a restriction is

 

or leak, lol

 

yep fully understand that concept

 

Ah, good point, yes you can actually end up 20lbs along the bottom axis from where you think you are too with a leak!
I was only talking about restriction, but thats a VERY valid point (which i had completely forgotten to mention to Lee as I just *assumed* he would have no leaks)

 

i would assume there's no leaks to make the 336bhp on 1.2bar in the first place ????

 

The turbine or just the housing?

 

Btw Thx to ALL for your input

 

both. its the bigger a/r's in this link
http://www.atpturbo.com/Merchant2/me...egory_Code=GRT

 

before i went back to the rolling road, i would rig up some equipment to the car

pressure gauges, on the exhaust manifold, after the turbo on the exhaust, before intercooler, measure temps on the inlet to the intercooler, and exhaust manifold

 

Me too.
I would also have 6 boost gauges connected to:

Compressor housing.
Intercooler Inlet
Intercooler outlet
Before throttle body
After throttle body
Most convoluted inlet just before the valve if possible.

 

I would try manifold and turbo boost gauges first on the road, if there is a minimal difference in them, no point in all the rest.

 

are you running suitable valve springs for turbo charging

 

I asked him that on another forum (i thought the pressures might be holding the valves open even after the cam lobe is gone) but i never got an answer, so i think perhaps he doesnt know

 

And i expected his mapper would have seen teh massive hydrocarbons present when this happens, so took it as a given YES.

All teh same though, sould have asked, well spotted Mr M

 

does anyone know what his mapper thinks is wrong as it is only his mapper that has had the benifit of examining the engine and all the data,or is it just a very complex problem known in the tuning industry as DIY itous

 

His mapper is John Nobles, they arent really DIY as such, lol

 

2.5 inch exhaust for 400 bhp

 

chip i wasn't refering to the mapper i was refering to the engine builder

 

Lee have you changed the 270 degree cam for a 250 and had no change what so ever?

 

he says just a flow restriction somewhere
exhaust,duration,springs etc etc.

 

2.5inch has flowed 400 on several cars with this engine so i ASSUME it will on mine! i know assumptions are the mother of all fook ups, but i gotta go with if its been done before? and i have a less restrictive exhaust manifold and turbo hotside! but any owt i'm not trying to find the last 10bhp to crack 400 its 85bhp off
but if fitting a 3 or 3.5 inch is the answer no problem, thats why i'm here to find out what i need / did wrong.

 

boost pressure drops across IC and at turbo outlet / plenum will be recorded today approx 3:00pm for results

 

Interesting topic, keep us informed.

 

Mike i'm willing to bet your back pressure is greater than your boost pressure

 

I'll take that bet, as it was measured at 2-3psi LESS with the smaller exhaust (3" splitting into two x 2ź"), it now has equivalent to 3.53" (4" splitting into two x 2˝") - which makes it fractionally bigger than Martin's, and I'm only running a poxy T4 ).

 

i think we should all turn up for his rolling session and sort it out

 

RESULTS:
just been out with pressure readings taken from the turbo outlet and at the plenum . i only had a psi gauge for the pre IC reading which i saw a max of 21psi and the apexi which is reading at the plenum showed a max of 1.25bar ????????????//
it was too much hassle to connect 2 map sensors to the ecu and data log them

 

its not for lack of enthausiasm on my part i tell thee

 

Less than 0.2 bar pressure drop, so your problem is not there, intercooler is okay .

 

 

i know mate,,,

 

Yes, the most interesting at the moment i think.

Strange problem too. 310-320bhp at 1,2bar is quite good I think, but hitting the wall and not getting any more power at all beyond 1,2bar is strange.
What power at 1bar?

Can´t think of anything that hasn´t already been mentioned tho.

Lars.