E-05 Rolling Road Figures, and Graph

[ibizacupra]

Originally posted by Glenn
The waters have been muddied somewhat by the Milltek D/P not actually being what it was supposed to be and by Bill's car requiring higher boost than the equivalent IHI'd Golf to obtain a given output which suggested that any restriction may not be due to the downpipe. However, it may be that even the IHI D/P on the Ibiza is more restrictive than the equivalent Golf version?

I think I said somewhere on here the MKIV outlet is going to be better flowing as there is more space... Rear engine mount is in the way on the Ibiza (which is MK2/3 Golf front end). tighter turbo outlet, but a packaging exercise as with all things Ibiza... Very small car for a 1.8T motor to reside in.

MKIV based cars can use Jabba's cast turbo utlet, which is larger and free'er flowing... runs into 3" downpipe also, vs 2.5" on Ibiza.. It is VERY tight under there... Engine mountings, movement are an issue... Driveshafts are mucho close to touching, and I have had to stiffen/replace my motor mounts to prevent the DP from hitting the top of the steering rack. It had to be heat wrapped to stop gaiters & engine mounts from melting... It aint easy.

10psi IHI boost produces over 250bhp and similar torque...
what will an E05 need to blow to achive the same (more torque tho)

E05 will run hotter to produce the same power levels, as its running higher boost to get there.

The Golf is an easier car for fitment... IMHO.

bill

 

[Madmile]

4 bar fpr, just buy it from your local Vw garage £65 all. The lower the resistance from the turbo back the higher the boost can be turned, a good quality high flowing 3" downpipe connected onto the Miiltek cat which in turn goes onto a 2.5" jetex or Milltek should free up the 20-30bhp missing i reckon. As you can tell from my posts i was sat thinking late night and i brought a few comments together.

1. Golftt was seeing 26psi, me and Custard 19-21psi, same turbo which in theory should run the same boost through it.
2. Dor said even the Milltek had a 2" bottle neck on the dp.
3. Common factors between power and lack of, were Injectors and Downpipe, and samco air intake pipe (known to be good for 5-8bhp so unlikely) 4 bar brings stock ibiza injectors to 305cc roughly (Audi TT size 317cc's i think). But our cars came no where near maxing the injectors out. As long as exhaust manifolds are identical, which if theres are stnd then they are. Then it could only be back pressure, Kev at revo told me he was using a custom 3" downpipe standard cat and Jetex 2.5" cat back, Milltek cat should offer less resistance than stock cat, we both have jetex 2.5" cat back, only other thing is the dp.

 

[Wilko]

Originally posted by Madmile
1. Golftt was seeing 26psi, me and Custard 19-21psi, same turbo

Don't know where you got that from? Car runs 1.55 bar max which is <23psi. I've actually turned the boost down to 20.5psi, as it's undriveable as the boost comes in with a wallop at 1800rpm causing massive wheelspin through second, and third in the wet.


Bill. If i ran 10psi on the e05 at >7k revs, I'd expect it to make 250hp just like the IHI. At 12.5 psi its making 260hp at 6500rpm. Would make marginaly less than the IHI, due to greater pumping losses.

The golfs injectors were maxed out at 4bar on the E05. Boost had to be reduced at around 5k onwards to keep them under 100% duty cycle.

Glen when you refer to pre turbine pressure loss, I assume you mean on the induction side of the turbo? I have done eveything I can to keep this to a minimum.

 

[ibizacupra]

Originally posted by GolfTTish

Bill. If i ran 10psi on the e05 at >7k revs, I'd expect it to make 250hp just like the IHI. At 12.5 psi its making 260hp at 6500rpm. Would make marginaly less than the IHI, due to greater pumping losses.

Not in an Ibiza....
We have yet to see an E05 perform as well in that installation.

Golfy runs 1.35 bar boost but turns 391bhp & 350lbft torque

Ibiza's are a pain... Dunno why, but they are.

 

[Madmile]

Correct me if i am wrong if i was to fit a complete 3" system from the turbo back would my boost guage read higher as long as no boost thresholds were hit or limp mode. Boost is pressure, same pressure less resistance ='s more flow, resulting in less boost required for more bhp/or same bhp. ????????

 

[Dormouse]

Originally posted by ibizacupra


Ibiza's are a pain... Dunno why, but they are.

Dor.

 

[Shock_Xe]

spoke to stainless guy today and had a new miltek dp/cat infront of us and it not the best design, He seems to think we could increase the dp to 3" and keep it all tidy and sue existing turbo flange/flex, so we have some 3" mandrel bent piping coming in the next day or so hopefully this will help,

The other thing im looking at is a 4bar FPR (can source for £40ea, and injectors.... But no one can seem to tell me what injectors would fit and what standard ones produce. Waiting for a call back off Jabba but if some one can fill in the blanks would appreciate it.

Thanks

Mike

 

[CustardCupra]

Spoke to mike T today about my problem with EO5 going into limp mode and he reckons it needs more boost , so i will adjust it by 3 turns on the actuator .
Mike also said the Ibiza will benefit from 3" Dp and also recommended looking at the cams .
Using the later ones off a Leon VVt head will give a bit more overlap and free up a bit more back pressure .

THE PLOT THICKENS

 

[ibizacupra]

Originally posted by Madmile
Correct me if i am wrong if i was to fit a complete 3" system from the turbo back would my boost guage read higher as long as no boost thresholds were hit or limp mode. Boost is pressure, same pressure less resistance ='s more flow, resulting in less boost required for more bhp/or same bhp. ????????

Pre or post turbine... where is the bottle neck?
(think of the exhaust manifold itself and exhaust turbine.... vs the downpipe)

Holding up the boost can be an example of pre-turbine back pressure and in this instance high rpm boost is a -ve effect pumping heat into the system.

eg... Smallport IHI motor... runs over 20psi to near 8K if you wind it up... Same turbo on largeport and this top end boost drops off, but higher power is produced... (more airflow)

 

[ibizacupra]

Originally posted by CustardCupra
Spoke to mike T today about my problem with EO5 going into limp mode and he reckons it needs more boost , so i will adjust it by 3 turns on the actuator .
Mike also said the Ibiza will benefit from 3" Dp and also recommended looking at the cams .
Using the later ones off a Leon VVt head will give a bit more overlap and free up a bit more back pressure .

THE PLOT THICKENS

Got some VVT cams...
Where/How would you time then up on a non VVT head?

If boost is held, the flow is being choked somewhere...
3" DP could'nt hurt peak airflow.

Get the Dremmel out on the exhaust manifold.... open it up as wide as you can.... Make a difference then I'd bet.

 

[Madmile]

A complete 3" downpipe may be a problem a mixture of 2.5 and 2.75" may be the only option. Or just a 2.5" dp. Opening up the exhaust manifold would certainly help.

 

[Shock_Xe]

Originally posted by ibizacupra

Get the Dremmel out on the exhaust manifold.... open it up as wide as you can.... Make a difference then I'd bet.

ahh theres a thought, havent done that yet

 

[ANDY BLUNT]

Thats this weekends project sorted Mike ,turbo off and grinder out. Andy

 

[Shock_Xe]

Originally posted by ANDY BLUNT
Thats this weekends project sorted Mike ,turbo off and grinder out. Andy

Is there an aftermarket one out there or can the existing one actually be modified?? Seriously considering this!!!

 

[ibizacupra]

Originally posted by Shock_Xe
Is there an aftermarket one out there or can the existing one actually be modified?? Seriously considering this!!!

Get your die grinders out and busy busy busy...

 

[Shock_Xe]

Originally posted by ibizacupra
Get your die grinders out and busy busy busy...

Got a lethal 12" angle grinder which may do the job :devil:

 

[Glenn]

Originally posted by GolfTTish
Glenn when you refer to pre turbine pressure loss, I assume you mean on the induction side of the turbo?

No, whenever I say turbine, I'm talking about the 'hot' (exhaust) side of the turbo, likewise compressor is the 'cold' side.

Pre-turbine backpressure is caused by : increased restriction to flow on the induction side meaning more boost is required to overcome it meaning higher compressor/turbine speeds or, a restriction to flow on the exhaust side - the turbine normally being the main culprit if on the small side - preventing the (possibly excessive) requested boost being achieved.

Quote max_torque :
"The reason the big turbo / manifold works for the 1.8T is because the larger turbine reduces pre turbine pressure for a given air mass flow, which improves the engines pressure ratio (less boost requried for same airflow = less compressor work = low air charge temp = less intercooler work, or a low plenum temp), and also reduces in-cylinder residuals that are hot and displace incoming fresh air charge, and cause detonation. Therefore you can run same airflow at less boost, more advanced ignition and with less fuel required to keep combustion temps sensible, All these things improve the engines BSAC, and help power output!"

 

[ibizacupra]

Originally posted by Shock_Xe
Got a lethal 12" angle grinder which may do the job :devil:

LOL might be a tad big to fit into the ports..
Worth spending time porting as big as you can.....

 

[Glenn]

Originally posted by CustardCupra
Using the later ones off a Leon VVt head will give a bit more overlap and free up a bit more back pressure .

Everything I've read so far about F.I. cams says that excessive overlap is bad as you end up forcing unburnt fuel/air mixture out the exhaust valve before it's had time to ignite? I could maybe see it increasing flow on the induction side so the compressor/turbine load is reduced? Must be a bit of a balancing act?

 

[Madmile]

Its all becoming a pain in the arse, i might just get the 4 core and let jabba take the strain and bang a stage 2 or 3 ihi kit on. Aint bothered how it gets fast as long as it does.