another 4agte dynoed.

[Stealer Of Souls]

That torque figure... That's at the wheels right?
How do you guesstimate the torque at the flywheel? Divide by the final drive then add a bit back on for losses?
So say around 340Nm @ flywheel?

[Bazda]

That torque figure... That's at the wheels right?
How do you guesstimate the torque at the flywheel? Divide by the final drive then add a bit back on for losses?
So say around 340Nm @ flywheel?

same thing happened on my dyno, the hub ones seem to work torque out a bit different..

[flygt4]

yeah the torque conversion to flywheel is a bit of mystery to me. ive heard a few different ways quoted.

question for anybody else using an ae92 gtz gearbox , are your ratios as long as mine? dynoed in 4th gear i assume , 235km@7403 rpm and the limiter is 8500 with a whole other gear to go

my wastegate is signifigantly louder at low boost , at 7psi its a lot different. can barely hear it at high boost.

oh and the slight glitch in the boost curve was ironed out later on with the boost controller.

and they must be 440's then , but they had heaps of headroom left in them

[IH8TEC]

was it out of a mr2 like mine? they meant to have longer ratio in 5th than other gtz's.

[flygt4]

no just the diff came out of an mr2 , the gearbox was a gtz item i believe. revving the box that high makes it interesting tho , 3rd gear is up to about 170km now

[Crucible]

Good effort mate, Id be wrapped if my sh*tta makes around that!!, well I know my turbo should be good for it anyways , shouldnt be too far before its back on the dyno and hopefully making some semi decent numbers this time lol....

[gmacrae]

Sounds like your turbine is pretty restrictive, ex gas pressures are building up so much at high rpm they're forcing the wastegate open, as its an easier route than squeezing thru the turbine, hence you cant keep boost stable up top. If its the stock audi spring, it will be very soft, and there's only so much your boost controller can do with a spring that soft. Try putting a tougher spring in it, that should keep it from bleeding off that couple psi

[flygt4]

cheers for the suggestion man , that was the other option that the tuner had considered too, either the turbo was physically too small or the wastegate spring too soft , as its a factory audi one. seems to be limited knowledge on these wastegates, but the boost curves are reasonably tidy up until i start losing boost at 20psi, so its working up to a point.

im actually really happy with it now , im going to try and keep it in one piece long enough to see some circuit and drag strip time, and set a few goals to chase at which point ill probly end up seeking more power. and so the cycle continues..

[matt dunn]

I had the same problem with my car on the dyno

Fine up to 18, but when we tried for 20 it would not do it.
Wastgate duty cycle at 100% so basically running on freeboost with no pressure on the actuator.

Spent far to much on a turbo upgrade to enlarge the wheels and make it flow more and back to the dyno.

Same HP but now we could only get 16psi boost. that really pissed me off.

Turned out to be a leaking BOV. Pulled it apart and ended up with 16 falt washers under the spring to increase the tension, and now I can have as much boost as i want. Will run up pat 25psi now if i set it too.

I know a lot of people in racing who have had BOV problems,
so definatly worth checking.

[IH8TEC]

i tried dummy fitting my new turbo tonight, and it wouldn't fit with that manifold i got, so it will be off to dan to get one made, the turbo is huge, such a tight fit so will be a bit longer till i get my results up

[Akane]

Are you guys running one of those pull type valves or whatever those HKS SSQV things? I was under the impression that it shouldn't leak as boost pressure rises it seals tighter or something.

[flygt4]

mine is a basic blue anodised adjustable valve.may be a turbosmart one its that kind of style , but yeah it wouldnt suprise me if that was an issue , as its a fairly basic item.
its also in a very odd place , right next to the compressor side of the i/c. its actually in a poor place as its the angle its on makes it the lowest point on the car under the engine bay


thanks for that suggestion matt , that sounds very plausible and ill be checking that out. thats sounds like the issue i have , as i can not hear the wastegate at all on that sort of boost , its not till it really gets going that it starts tapering back too.

ih8tec , its hard to get a decent turbo to fit in these applications, even my relatively small one only has aprrox 5mm clearance from the exhaust housing to the radiator. the manifold was designed to keep the oil filter in place tho.

[trueno_20v]

hows that link going? i have to go with a link ver 5 now as haltech said the interceptor wouldnt be the best on my car, so hopefully with the link it still runs ok eg cold start etc, hows yours?

IH8TEC said: i tried dummy fitting my new turbo tonight, and it wouldn't fit with that manifold i got, so it will be off to dan to get one made, the turbo is huge, such a tight fit

put a civic half size radiator in like me, ive got plenty of room even eith the oil filter on

[matt dunn]

Are you guys running one of those pull type valves or whatever those HKS SSQV things? I was under the impression that it shouldn't leak as boost pressure rises it seals tighter or something.

The HKS SSQV BOV's are actually the worst type for leaking actually.
They are fine on low and mid mboost but they dont take high boost even though they apply boost to both sides of the diaphram.

My one was also a basic turbosmart one. If it is the type where you adjust it from soft to hard, screw it round to soft and keep screwwing till the lid comes of. Put a spacer under the spring and try again.
I needed about 18mm of spacers. I used washers.

Matt

[Bazda]

hows that link going? i have to go with a link ver 5 now as haltech said the interceptor wouldnt be the best on my car, so hopefully with the link it still runs ok eg cold start etc, hows yours?

IH8TEC said: i tried dummy fitting my new turbo tonight, and it wouldn't fit with that manifold i got, so it will be off to dan to get one made, the turbo is huge, such a tight fit

put a civic half size radiator in like me, ive got plenty of room even eith the oil filter on

link with quad throttle bodies, daily driven car hmmmmmm

[trueno_20v]

why are quads so hard to tune??

[flygt4]

My one was also a basic turbosmart one. If it is the type where you adjust it from soft to hard, screw it round to soft and keep screwwing till the lid comes of. Put a spacer under the spring and try again.
I needed about 18mm of spacers. I used washers.

Matt

thats exactly what ill do , cheers for that. its a bit worn from being in such a stupid place so i cant tell what brand it is , but you use an allen key to screw it from hard to soft. it is blue like the turbosmart ones tho.


yeah link+ quad throttle bodies makes it quite difficult to have a good tune for part throttle applications , such as daily driving etc.
someone else may be able to explain it better than me , im no technical wizard
it is possible to get a fairly decent tune from it , but it takes a lot of finetuning on the road after the dyno side of it. im pretty happy with mine now.
my link has no coldstart, but its actually not too bad now, its been tuned so that itll idle almost normally at cold now , whereas before it would be about 4-500rpm and very lumpy

[Crucible]

i tried dummy fitting my new turbo tonight, and it wouldn't fit with that manifold i got, so it will be off to dan to get one made, the turbo is huge, such a tight fit so will be a bit longer till i get my results up

What Turbo are you upgrading to Brendon?, same as mine?

[matt dunn]

thats exactly what ill do , cheers for that. its a bit worn from being in such a stupid place so i cant tell what brand it is , but you use an allen key to screw it from hard to soft. it is blue like the turbosmart ones tho.


yeah link+ quad throttle bodies makes it quite difficult to have a good tune for part throttle applications , such as daily driving etc.
someone else may be able to explain it better than me , im no technical wizard
it is possible to get a fairly decent tune from it , but it takes a lot of finetuning on the road after the dyno side of it. im pretty happy with mine now.

Your BOV sounds a bit different to mine as mine has no allen key, just grab the body and turn. You may have to figure out how to get into yours.

The reason links are so hard to tune is that for a small amount of throttle movement and a sligfht change in manifold pressure is a great increase in actual air flow into the engine, which makes the zones very different from one side of the zone to the other while in the same zone.

Matt

[Crucible]

The HKS SSQV BOV's are actually the worst type for leaking actually.
They are fine on low and mid mboost but they dont take high boost even though they apply boost to both sides of the diaphram

Oh Gutted!...Really Matt???I was under the impression that the the more boost you run the better they seal, thats why I just fitted one to mine . Do you know of people having problems with them at high boost??