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Piglet's Rebuild Of His Busted Tomei 2.8

Piggaz
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Piggaz
Piggaz

Car is finally booked into Insight on the 19th of April for the ECU, fuel system and sensor wire in plus the tune. Thats the good news. The bad news is that V-cam aint gonna fit with my pistons and ho

Piggaz
Piggaz

Small update.... ITS RUNNING. Fired first go! Smells like burnt dust apparently .

Piggaz
Piggaz

A 9174 would just make the EGP pressure issue worse and in my mind it seems like a bit of a GT RS shit going on. Not that it's horrendously bad (It wouldn't be no twin buttplug pressures), That's NOT

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Piggaz Grand Master

Piggaz

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3 minutes ago, Juan_2_3 said:

are you able to overlay the -5s results?

Different dyno

-5 was RWD

8374 is 4WD.

i can, but ignoring dyno's it feels like the car has a 3.4 in it. Absolutely NO comparison.

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IMACUL8 Veteran

IMACUL8

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1 hour ago, Piggaz said:

That's where she ended up on E80.

120k turbine speed.

Scott said it will go 500 but he was happy leaving it there. 

 

IMG_5505.JPG

Awesome effort mate.

Monday was a public holiday over here in the West and I spent some of the day reading through your thread again from start to finish.

Your honestly and openness in your results and parts choices etc - well done mate and a big thanks.

You have convinced me to move my ass and get moving on updating my setup ;)

Awesome thread and car - can we get some updated pics of the whole car....

Dan

Edited by IMACUL8
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Piggaz Grand Master

Piggaz

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1 minute ago, IMACUL8 said:

A

Awesome effort mate.

Monday was a public holiday over here in teh West and I sent some of the day reading through your thread again from start to finish.

Your honestly and openness in your results and parts choices etc - well done mate and a big thanks.

You have convinced me to move my ass and get moving on updating my setup ;)

Awesome thread and car - can we get some updated pics of the whole car....

Dan

Cheers man.

Yeah. Sure.

Things to do;

- wash it

- wheel alignment

- remove redundant gauges and boost controller from car

- make catch can for box ? (Although it's stopped spewing. Self level FTW)

- farken drive it!

Pick up is tomorrow. 

Thats the most power anyone has made on Scotts dyno with an 8374, with still some left in the tank.

 

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usmair Mentor

usmair

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13 hours ago, Piggaz said:

@usmair

That's roughly 26 psi tapering to 23 ish psi topend. 122,000 RPM turbine speed. If we went all in it would have been lucky to see another 0.5psi uptop. Turbo is pretty much done. 

Thanks.

I'm not 100% sure but I think mine kept making power from 25 up to 30 psi where I told tuner to stop due to stock bottom end. The 8374 has made 550kw at 34psi on JEM's dyno before.

Maybe it was out if its efficiency range and exceeding safe turbine speeds - say past 27psi - but it made power. TBH i think JEM's dyno is a little on the happy side but the tune is good so I'm not bothered.

Mine sees 31 psi regularly and no issues in the year it has been on the car.

*awaits flaming*

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Piggaz Grand Master

Piggaz

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17 minutes ago, usmair said:

Thanks.

I'm not 100% sure but I think mine kept making power from 25 up to 30 psi where I told tuner to stop due to stock bottom end. The 8374 has made 550kw at 34psi on JEM's dyno before.

Maybe it was out if its efficiency range and exceeding safe turbine speeds - say past 27psi - but it made power. TBH i think JEM's dyno is a little on the happy side but the tune is good so I'm not bothered.

Mine sees 31 psi regularly and no issues in the year it has been on the car.

*awaits flaming*

Boost is almost meaningless. Throw the gauge in the bin.

Want more boost? Use a less effecient setup. Put a heap of shit intercooler on it, whatever.

Top end, the boost between Pete's 3.2 and my 2.8 are the same. The difference? Most of it would be the head.

Two car's, one with a well thought out head and one with a stocker at the same turbine speed will be reading vastly different pressures. 

Pressure doesn't always mean "x" flow when comparing two setups. If I could make the same power at 10 psi, I would.

Your 30 psi may be reading the same turbine speed as my 23 psi for example. Thing is you don't know where the turbo is without a speed sensor.

 

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Lithium Grand Master

Lithium

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50 minutes ago, usmair said:

Maybe it was out if its efficiency range and exceeding safe turbine speeds - say past 27psi - but it made power. TBH i think JEM's dyno is a little on the happy side but the tune is good so I'm not bothered.

Mine sees 31 psi regularly and no issues in the year it has been on the car.

*awaits flaming*

As Piggaz set, the boost pressure is a tiny part of the story.  Without going far at all into the big world of turbo matching to engines etc - I'll try and give a very simple picture of what the difference between your motor at 7000rpm and Piggaz one could hypothetically be.

Say your engine at 7000rpm is running 31psi - so pressure ratio of 3.1, and has ~105% VE at those rpm.  You get a relatively bullshit but for the point of this story a reasonably descriptive 2.6 x 3.1 x 105% = 8.46 effective litres of air moved per engine cycle at 7000rpm.

Now lets looks at Piggas HEAVILY developed head/everything setup with a 2.8 litre stroker.   Lets say its at ~24psi (pressure ratio 2.63) and has ~115% VE at those rpm... 2.8 x 2.63 x 115% = 8.47.

It is entirely possible to have the same amount of air moved with much less boost using a different engine combination and the same turbo, it is entirely plausible that Piggaz' turbo is working as hard at 24psi as yours is at 31psi.    Put the same turbo on a 4G63 and you could run 35psi through it and have a LOWER turbine speed... ie, it is running more boost and is actually safer.

We talk about turbine speed being the problem, not boost.   You have no turbine speed sensor so we have no idea whether you are at a safe place or not, but if Piggaz tried running 31psi at high rpm I am certain he'd run into some kind of limit.   There is the possibility yours is actually fine, its just that the power level etc suggests that its in a place we'd not normally expect but if the dyno is happy and its making the power fine then it may actually be all good.

What kind of trap speeds are you running?  I am guessing Piggaz car could be in the territory of 140mph.

Edited by Lithium
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