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Thought I'd better post up all the latest on my project since I havent posted for a while.

Latest thing to happen to my Piazza is a cracked head which finally caught up with me a week ago. For those of you that saw my dyno results in another thread on this site, you would have seen that running over around 10psi with the standard setup makes it run really lean throughout the rev range. Well, I found that out after I had mine turned up to 14psi for around 6 months. I quickly turned it back when I had it dyno'd. Anyway, the lean running over that period is the cause of the crack in the head next to the exhaust valve in cylinder 2. I was lucky to be driving on it so long with the crack slowly opening up for about 6 months, however the crack finally became too big and I had water mixing with oil.

Everyone who wants to run over 10 psi boost with the standard setup should read this.......dont do it!!! This is the result:

[thmb]Http://www.isuzupiazza.com/puplic/images/83845271.jpg[/thmb]


However, this hasnt all been bad as it has given me an oppurtunity to get the Rodeo runners and injectors on the new head ready for the Motec. Nearly have all the sensors I need for the Motec, just need to mount it and start wiring it up which is all straight forward. I will be using the single throttle from the Rodeo when I get the Motec up and running, but for the time being I am running the Rodeo runners (which are a fair bit larger in diameter) with the Piazza plenum and throttle body. Heres a pic of the manifold with my new reco'd head. This should be going back on the block tomorrow night hopefully!!

[thmb]Http://www.isuzupiazza.com/puplic/images/39854922.jpg[/thmb]


As far as the ignition side of the ecu setup goes, I am using a Rodeo CAS with custom 60-2 trigger wheel, this integrates well with the Motec and is simple to setup, not to mention bolts straight in of the original distributor.

[thmb]Http://www.isuzupiazza.com/puplic/images/11795514.jpg[/thmb]


The turbo I have for the upgrade is a VF8 from a Subaru Liberty/Legacy, its a fair bit larger that the Piazza one, flows enough for around 280HP and bolts straight in place of the old one with some minor mods.


[thmb]Http://www.isuzupiazza.com/puplic/images/47359013.jpg[/thmb]


Thats about it for now, hopefully will have a bit more to add in the next couple of weeks.

Dave

Done some porting to the head to bring the inlet ports out to 4ZE1 size?
Whats with that turbo inlet there's no way to attach anything to it!

The ports have had a little work done to them, they are larger than the piazza ports but not quite as large as the rodeo ones. Obviously this is not ideal and the plan is to open up the ports on the head eventually, just have to get the car back on the road ASAP.

The turbo has a flange that bolts to the front cover with a gasket in between, not the best setup but thats how they did it. I am modifying the flange to fit with the piazza piping.

im using a vf8 at the mo its not a bad turbo

just a little tip i used the exaust turbine and housing it fits straight onto the vf8 setup boost comes on a tad later but its still boostin hard at redline


when u go to fit the whole setup into the car take the green plug out of the back of the alt it makes it a shit load easier to get it to fit

after youve mounted the turb reach up from underneath the car and u can put the plug back u will have about 5mm clearance between the plug n the turb housing

Cool thanks for the info.

I have already swapped the piazza turbine housing and wastegate actuator onto the vf8. Did you port the wastegate at all to control boost cause I have read that this needs to be done when doing similar swaps on Ford Lasers? What boost are you running? And is it making much more power? Are you using the standard fuel and computer setup??

Thanks

Dave

The head could have cracked for any reason. I wouldnt put it down to the leanout. Its possible but i wouldnt say entirely to blame.


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Id say the wheel and housing on the Subaru turbo will be a different profile to the Piazza one. is on the RHB5.


That bolt on flange idea is a good one i rekon. If you need 45deg or 90deg into the turbo inlet its easier to make the flange conform than hose bends.


Bob.

I agree you could never be 100% sure on the cause of the crack, however, I had the head off about a year ago and looked over it and it was running perfect back then. The problems started happening a few months after I turned the boost up, small bubbles started appearing in the water and the car would run on 3 cylinders at start up until the water cleared out. It was pretty conclusive to me that the head had started to crack and I was lucky that it held in there for so long. That together with the fact that the crack is on the exhaust side (the hotter side, especially when running lean) and on the edge of the bore (area prone to detonation affects) is why I am blaming the lean situation under high boost as the reason for the crack.

The turbine wheel is very similar to the Piazza one, the compressor side is totally different. The Piazza turbine housing does fit staright onto the VF8 but the VF8 has a 25mm wastegate, the Piazza a 20mm.

use the piazza ex turbine and shaft they are almost the same the subaru shaft is about 3mm shorter

slip them into the vf8 housing and use the piazza ex housing

presto strange but true

ive got a crack in my wastegate housing common ive heard

i have the wastegate jammed shut and am gettin 10-11 psi in the manifold crude but works

Well, after working on my car for the last week solid, I finally got it all back together and running tonight.

Turns out the head that bought and got reconditioned had a reground cam in it with more lift and more duration, should here the car idle now.....sounds mean. The cam has made it a little spongy down low but it goes a bit better up high. Trying to find out the exact specs of it, it has 208 stamped on it, from what I have found searching ozgemini forums it could be a Clive Cams regrind.

Also running the fuel rail and green top injectors from the import Piazza engine I have spare. The injectors are not the hose tail type, they plug straight into the fuel rail, have no idea if they flow more compared to the hose tail type, anyone know??

Hopefully this is the last major engine work I have to do to the car before I start looking at fitting the Motec, turbo, intercooler, etc.

Dave

VF8 turbo is now on the car. Havent pushed it yet because I am afraid that it may be running lean. Going to put an adjustable fuel regulator on it tomorrow and crank some pressure into it to be on the safe side. Here's some pics of the turbo and wastegate mods.

[thmb]Http://www.isuzupiazza.com/puplic/images/12112081.jpg[/thmb]

[thmb]Http://www.isuzupiazza.com/puplic/images/87814681.jpg[/thmb]

[thmb]Http://www.isuzupiazza.com/puplic/images/16354021.jpg[/thmb]

[thmb]Http://www.isuzupiazza.com/puplic/images/97223719.jpg[/thmb]

That's sweet cops wouldn't be able to pick it from a stock setup. Any pics of it all installed?

Thats the point!!!

I would post up pics of it installed except there is nothing to see really cause it looks so standard!!

so jelouse.

dude that looks same as mine nice setup huh!!!!

what rpm does boost start?

and what boost r u running at the mo??

I havent actually driven the car properly yet. I have been driving around at quarter throttle everywhere cause I dont want to risk running lean under load and cracking another head. Been there...done that. I am going to the dyno on Thursday to check mixtures. The turbo doesnt seem to have any more lag, in fact I think it spools up earlier. When I pulled my old turbo off I found that the water outlet banjo fitting was clogged up with crap and there was no water flowing through the turbo. This may have attributed to my turbo running a bit hotter and therefore the lag might have been more pronounced. I think once the Motec goes on and I get a good tune into it it will be a really torquey setup and my aim of this project is to have a good daily driving setup. The turbo is good for around 200kw at the motor so somewhere around that is the aim by the end of it.