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Hay guys!..

This was my situation..

I baught a R32 GTST that was stolen/revovered/stripped from an auction. Car is in mint condition.. Interior is spotless.. engine bay is shmick as! No rust at all.

At the moment, it does not have a turbo, ecu, intake pipeing, AFM or box.

I have a lazy RB20DET laying around with all the parts needed for the conversion.

Now.. here is my problem..

The mods that were done are apprently awesomely ghetto and mad dodgy..

The previous owner said it has excessive blow by..

The block is of a 25 that APPARENTLY has 1mm oversized pistons (or something of the sort that equates to a 2.6L)

It is fitted with an RB20DET head with MINT cams (beleived to be stockers).

Do I:

a) blow it all off and swap back to an rb20DET and sell for a shitty 9 - 10K? (This would mean I would have to get a new welsh plug fitted that blocks off a hole at the rear of the block, ie. near firewall AND get the block chemically cleaned. Prices for either?)

b) Hope the bottom end is not rooted, buy a 25DET head.. convert to full RB25DET.. attach R33 turbo (have at home) and sell for ~13K

c) Buy another Rb25DET and swap engines. This means I make less money in the end.. but will be running better.. AND will have spare 2.5 block with forgies.. AND a spare 20DET head.

How can I cheak (in the backyard) for blow by? Will a preassure test show me this?

Any advice on what ruite/combination to go?

Is there any way I can learn more about the engine without stripping its guts out?

Can anyone recomend me any tests to learn more about the bottom end?

What should be done?

Thanks in advance guys! :ninja:

Edited by GTS4WD
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I would check out the block again, because without some major modificatons a rb20 head wont fir a rb25 block, not saying it cant be done, its just very unlikely - and more likely someone has told you porkies (which sux), in which case I would go with a) welsh plugs are easy + a can or 2 of degreaser will work wonders

Oh, and a leak down test will tell you heaps

Edited by Medium Dave
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I would check out the block again, because without some major modificatons a rb20 head wont fir a rb25 block, not saying it cant be done, its just very unlikely - and more likely someone has told you porkies (which sux), in which case I would go with a) welsh plugs are easy + a can or 2 of degreaser will work wonders

Oh, and a leak down test will tell you heaps

Well the previous owner said it had coolant comming out of the exhaust.. So i figure the galleries dont aline..

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If you plan to simply repair and sell, then put the RB20DET in it.

Check out the RB25 for yourself (check the engine number to be sure it IS a 25).

Right near the bell housing.. Big flat bit.. "RB25"..

If I keep a stock Rb20det.. i sell it for cheap.. I want to gain something outa this.. :ninja:

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After digging further into the situation I found:

- Compression in each cylinder ranged from 80 to 170 psi.

- The HEAD GASKET was made from A WHEETBIX BOX and cheap gasket goo (which was of course blown)

- The galleries of the block and the cylinder didnt aline.. hence causing to the car to over heat. There was TWO Welsh plugs completely blown out of the head.

- The cylinders were HITTING the cylinder head

- The rings seem to be goneski as well..

...

Here is the scary part..

All this work was done by an "RB Specialist"

The take home messege is dont trust any old work shop.. or do the work yourself! At least be 100% sure you know what the shop is doing.. and they are doing it correctly..

Edited by GTS4WD
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I thought I may aswell ask this here instead of starting a new thread..

the pistons have "STD" and a big "01" in a circle right in the middle of them..

The previous owner said it had forgies that did about 1000km.. now.. to me.. these look way older than that..

Anyone seen these markings before?

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I don't see why this justifies a warning to all modified car owners?

You bought a shitbox - you should have inspected it first.

Deals that are too good to be true often are.

If it was missing all that crap from the auction, you would suspect something. Instead of seeing it as a bargain, I woulda seen it as a heap of junk and moved onto the next car

Edited by MANWHORE
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I don't see why this justifies a warning to all modified car owners?

You bought a shitbox - you should have inspected it first.

Deals that are too good to be true often are.

If it was missing all that crap from the auction, you would suspect something. Instead of seeing it as a bargain, I woulda seen it as a heap of junk and moved onto the next car

well.. its a warning about how dodgy some workshops' work is.. its a notice to be warey where and to whom you take your car to.. I mean this work was done at a workshop.. a workshop that didnt know a 20 head does not mate up with a 25 bottom end.. A workshop that used a wheetbox box and $2 gasket goo for a head gasket. So thats where the warning is.. This workshop is acctually considered as an "RB specialist"..

It's not like Im pissed off about it at all.. Im enjoying it.. its an awesome project.. another excuse to get my hands dirty.

And.. yes.. its got all these things wrong.. but in hindsite.. its still worth it.. :laugh: There's nothing like the satisfaction.. What ever I do with it.. I wont end up in debit.. and thats why Im not so worried about it..

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Weetbix box gasket? WTF? If u knew it had coolant coming from the exhaust Y would u buy it or was that a later discovery? Just put a 20 back in it, cheap enough to do and saves a lot of costs pulling 2 halves of 2 different engines apart and sorting out whats still decent and what has been damaged and replacing it. Alternatively there is a 25 already mounted in it so thats another option. 20 would be cheapest for u to sell the car quickly.

Liam

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You'll be right matey. If it was how you bought it (missing bits etc), i'm sure you got it for a good price.

Even if you were to chuck the whole motor out, pick up a second hand rb20 from the wreckers for $400, chuck it in, you'll be laughing.

Think of it as having bought a rolling shell. It's up to you how you want to customise it - how much you want to spend etc. If you have more to spend, chuck in an rb25, more again, build an rb30 :laugh:

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