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Here we go again...


vvteye

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Issue

After a couple of months of trouble free motoring following the engine and gearbox rebuild and 410hp at the fly recorded, I thought i would start tarting up the car, starting with a nice set of wheels. Before I got a chance though, I noted a loss of power predominantly with the second turbo failing to boost. This was confirmed on Thors rolling road.

 

Diagnosis

Yesterday it was confirmed that compression is low in 5 and the tubby is receiving signals and spinning but no boost. This is leading towards a theory that something has parted company in the cylinder (bit or valve or piston) and has taken some blades out of the 2nd tubby.

 

Cause

This is possibly due to a number of causes.

- A run in period that had 2 overheats from what turned out be a sticking thermostat (1st blew a pipe, 2nd split the rad)

- the delimiter issue for a vvti tiptronic which has never really worked and changes gears harshly changing down when pushed to gears needing 700 revs

- first few thousand miles of running lean where it was noted that despite being an obvious BPU the fuel pump had not been upgraded to a walbro

- Crappy intercooler just replaced with a CW SMIC but all a bit late

- a seized rad fan that despite not showing high temp on the dial, certainly didn't help matters

 

I have hammered the car following the rebuild through the rev range but thats what this is for right!

 

The solution.

- Stepping in all the dog shit i can find to improve my luck

- engines coming back out and issue with 5 cylinder will be sorted.

- acceptance that I will never get the tip to work properly with a vvti delimiter so I am going for getrag 6spd conversion

- Spal rad replacement

- Single turbo conversion

 

Funding.

- MKIVstore Warranty is not covering due to causes above but interpro are helping limit the labor costs (thanks guys)

- pm me for details of my paypal account where all donations will be greatfully received

- the 1000/1 outsider coming in 1st in the Grand National today

- Selling a complete vvti tip conversion to the Yanks (Gamer included)

- Selling an old mobile phone to the Nigerians for £10K on fleabay

- Selling the wife and kid to the Eastern Europeans

 

Advice required

 

What Single?

- I don't want to change fueling now apart from piggyback Map ecu (but may later),

- Need it for a daily drive . (Mostly lanes and dual carriageway) and the occasional track/strip day

- Want to keep the SMIC so around 500 rwhp will suffice. Want little turbo lag as possible and max bost by around 4500 revs.

- Want cheapest place to source single conversion kit and map ecu.

 

 

I was very down :( but now I'm excited at the prospect :eyebrows: Really pissed off that I won't be driving at Suprapod next week but i will be there to watch.

 

Thanks for listening ;)

 

you know it worth it...

suoe.jpg

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A piece of metal from the engine won't find it's way back to the turbo.

 

What compression readings did you get on each cylinder, how far out was no.5?

 

I would find out what the actual problem is first before fearing the worst.

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I agree with Nic, it would be a long shot as the only piece of metal that could possibly find its way through the exhaust side of the turbo would have to be a bit of spark plug, or valve (big long shot) and these would show very quickly by a misfire, or non fire of the plug, if you have been overheating and running lean then you are very likely to have been getting det, which will destroy plugs first especially iridium.

So what is the compression reading on no 5? and are you/ they sure turbo problem is not down to the more likely cause of VSV/bypass valve etc?

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Nice one guys.... thanks for the interest

 

I am fearing the worst in order to identify the maximum funds required to sort this but thanks for making me a little better. Now I may be wrong here coz I'm relying on a memory of something that I don't really understand. I think compression was 150 in all cylinders except 5 which showed 110. Following a leak test it was also confirmed to be the exhaust side. (sorry if this doesn't make sense, but keep the thread going and I can confirm this on Monday). The thing I have currently committed to is the engine coming out to further explore the issue on 5 and the tubby examination. I have also ordered the 6spd from Jezzybabes.

 

So no committment on the Single conversion at this stage but whilst the engine is stripped and the diagnosis is clear, then I have to make a move.

Thanks again;)

 

Maybe jodyT will have a better recollection of the facts

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Nightmare.

I wouldn't have thought the fuel pump would have been the problem. Your car is a lot newer than most of the BPUs out there and a lot of them are on the stock 13 years old pump OK.

 

If you want to avoid the expense and hassle of going single I know where there's a spare set of VVTi turbos (They're different to the pre-VVTi TT turbos). I was thinking of maybe having them myself incase I ever want to convert my VVTi back to stock.

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If you want to avoid the expense and hassle of going single I know where there's a spare set of VVTi turbos (They're different to the pre-VVTi TT turbos). I was thinking of maybe having them myself incase I ever want to convert my VVTi back to stock.

 

Never knew they were different more info please?

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okay how did i miss this?? That's terrible, i thought Toyotas were reliable :(

 

Good your finally getting a conversion to a manual then you can actually drive the car :p Nurburg trip end of May ;)

 

More power so soon ! My bro's looking at this as his tubbies are on the way out on the Rex as well.

 

Hope you get it sorted quickly, your car spends more time off the road than on.

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Well today I received the news and it's not good (God knows why I expected any different).

 

Couple of exhaust valves bent, Piston fooked, detonation damage to the head and cylinder. So it's gonna need another rebore and skim, the 2nd in 6 months. This will mean the Pistons won't fit so a new set of bigger ones are required. This is going to cost close to £4.5K plus the £3K for the manual conversion.

 

The only good news is that the tubbies MAY be ok. :rolleyes:

 

So Single is not an option now unless this tips the balance on my marriage and I wasn't initially referring to that type of single.

 

Maintenance bills in excess of £15K wasn't what I was expecting from my first year of Supra owenership.

 

I'm not sure whether to reach for the prozac or the 12 bore :(

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A new short block is around £1600 I believe. But it doesn't come with a head or any ancillaries though (oil pump, etc etc) and would still need stripping and checking really.

It would sort out rebore and pistons issue but probably not save all much money.

 

I have a spare standard (86mm bore) VVTi block and pistons with a knackered bottom end. Maybe John could make use of that somehow by fitting his crank into it. I'd be willing to donate it seeing as he's had so much bad luck.

 

I also have a spare VVTi head but wouldn't want to give that away. They're like rocking horse sh!t.

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I have a spare standard (86mm bore) VVTi block and pistons with a knackered bottom end. Maybe John could make use of that somehow by fitting his crank into it. I'd be willing to donate it seeing as he's had so much bad luck.

 

That is such a decent gesture, Thanks Jake. However I have to make sure the warranty this time is watertight and to do that it either has to be new parts abnd the engine has to have been bored/skimmed by their 3rd party etc. The bill is looking better as they have dropped it by £500 and told me that it included an uprated clutch for the conversion as they thought I was going single. This is therefore an option worth about £350.

 

The question I have now been given is do I want to upgrade the conrods as this futureproofs things if I do lift the HP later in the cars life. At a cost of £950 this is a big question indeed. Any thoughts?

 

 

Burn it, claim the insurance and buy another ! :)

 

I tried and only managed to set the 5th cylinder on fire so really need a skilled arsonist :p

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