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Dooie Pop Pop
New Member
yeah i did tell you all about this:roll: its what happens when you derestrict the exhaust. Ginga had no problem with a goose and standard elbow but i had problems with my 3inch jobby. im not sure what the minimum boost i could run in that condition was without surging but iirc it was circa 1.5-6 bar, now its around 1.2. this turbo really is as big as you can go with an internal wg.
think it cost me £70 for the honing and new penny washer from turbo dynamics. if they are supplying your new turbo then i know what i would do.....
failing that buy the external jooby;-) or fit the larger .84(i think) exhaust housing which would give more power but boost slightly later iirc.
stu
ps i think Robs got it in for quick spooling tubby' s at the mo;-):lol:
think it cost me £70 for the honing and new penny washer from turbo dynamics. if they are supplying your new turbo then i know what i would do.....
failing that buy the external jooby;-) or fit the larger .84(i think) exhaust housing which would give more power but boost slightly later iirc.stu
ps i think Robs got it in for quick spooling tubby' s at the mo;-):lol:
Rishi
Still waiting on some shims!
I think what they are getting at is to use a lesser trim turbine wheel to reduce the the flow capacity in hope of removing the boost creep... i think thats the wrong way to go about it to be honest...
I personally would use the full size 60mm trim from the GT3071 and use the external wastegate...
You don't want to reduce trim and thus flow capacity to reduce/remove boost creep because then you are reducing the performance of your turbo...
I think that the GT3071 is the limit for an internal wastegate... It seems to struggle... Now increasing the engines breathing efficiency will cause the turbo to spool quicker but also remember that by doing so you can actually run into turbine backpressure if you are using too small a turbine housing...
How using a small turbine housing is good for fast spool up but would only recommend when using this turbo at low boost...
When you start running high boost you will find the turbine housing too small... Yes it will spool quicker but at higher boost and engine speed you will hit a barrier of back pressure... For this reason you need to be using a larger housing to accomodate... This adds a little lag but allows for a more efficient flow at higher engine speeds and overall greater top end power...
Hope all that is some use to all of you...
Rishi
I personally would use the full size 60mm trim from the GT3071 and use the external wastegate...
You don't want to reduce trim and thus flow capacity to reduce/remove boost creep because then you are reducing the performance of your turbo...
I think that the GT3071 is the limit for an internal wastegate... It seems to struggle... Now increasing the engines breathing efficiency will cause the turbo to spool quicker but also remember that by doing so you can actually run into turbine backpressure if you are using too small a turbine housing...
How using a small turbine housing is good for fast spool up but would only recommend when using this turbo at low boost...
When you start running high boost you will find the turbine housing too small... Yes it will spool quicker but at higher boost and engine speed you will hit a barrier of back pressure... For this reason you need to be using a larger housing to accomodate... This adds a little lag but allows for a more efficient flow at higher engine speeds and overall greater top end power...
Hope all that is some use to all of you...
Rishi
Dooie Pop Pop
New Member
where did i mention a smaller trim:?
how does it?
im not getting backpressure that im aware of (please explain seeing as its you that thinks its good for 2.1+bar)) and it was holding 1.6 at the redline no problem
im not intending on pushing it any harder to be honest. if anything i' ll be working to gain more from what iv already got;-) its more than enough for a road car and quite a ****ing lot on the track so im happy anyway
scuse my ignorance in this matter im not that clued up on turbo stuff:?
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Rishi
Still waiting on some shims!
Dooie Pop Pop said:
Not you... The Yanks...
Dooie Pop Pop said:how does it?
im not getting backpressure that im aware of (please explain seeing as its you that thinks its good for 2.1+bar)) and it was holding 1.6 at the redline no problem
im not intending on pushing it any harder to be honest. if anything i' ll be working to gain more from what iv already got;-) its more than enough for a road car and quite a ****ing lot on the track so im happy anyway
Well i said you may or can run into backpressure with the 0.64 at high boost levels...
See how you get on at 2.1bar (if you go there) with a 0.64 A/R housing... I would be suprised if you don't set any backpressure or lose out on top end power... Using a 0.86 A/R may allow you to hold boost better - the 1.85bar you are running mid range - at higher engine speeds too... But then having the 60trim turbine could help that too...
Will just have to wait and see how people get on when they start to push the turbo with their various housings and trims..
Rishi
D
danmo
Guest
What is boost creep?