Staffi

iTrader: (1)

Folks, what is it that exactly causes them to crack?? is it too much boost, horsepower, torque?? genuine question as i don't really know....

martysmartie

iTrader: (1)

I would think a combination of all the things you mention.

Martin

wibbler

Harmonics are a problem too, not obvious to a lot of people and can break all sorts of bits.

cossie4i+

iTrader: (15)

Will be fine at your power

Steve

Staffi

iTrader: (1)

Steve,

FFS post a serious answer for once..

cossie4i+

iTrader: (15)

You want ME to tell the truth lol

Steve

Staffi

iTrader: (1)

Err, yeah, that's why i did the thread, enlighten me o wise one....

cossie4i+

iTrader: (15)

Im sure it will be fine with a T35, might also be fine with a GT35 or T4

That good enough for you ?

Steve

Staffi

iTrader: (1)

COONT.................

Go and drive a train somewhere

cossie4i+

iTrader: (15)

Happy with the answer then lol

Steve

v man

i ran one at 32 psi
low comp
ported head
bd14 and 16
500 cooler
t34 .63

and never had an issue

car was used everyday
had its fair share of stick too

Paul_RS

iTrader: (4)

Talk to Karl next time you are at NMS. He's quite alot of knowledge on the 205 blocks. He can tell you what he's done and hasn't done on them

Staffi

iTrader: (1)

Lol,

Sorry to sound twatish, that's childs play though, i mean that in a lvoely way you know that...

I ran one @ 443bhp for a good while, just want to know what makes them crack tbh, but i guess as said above, it's a combination off all mentioned..

rsmark86

iTrader: (3)

ive heard its down to to much boost most of the times and not to use stud and nut kits....

ive seen one tho at 500+bhp and its reliable with gt30 and omex and been like it for 2yrs and on track aswel.... just depends on whats fitted with it

Rsmat

iTrader: (2)

The 205 will take plenty more than people think really.

You will be fine pete with what you have/want.

Staffi

iTrader: (1)

Mat, it's not really power i'm questioning, seems like no-one knows the exact answer, i'm sure Rainbird or some other brain box will tell us soon enough..

rsmark86

iTrader: (3)

alot of people tho use them with aftermarket managements and gt series turbos with no problems

but someone said to me they crack around the head bolts due to the block thickness and strenth and arps make it alot worse...

nms tend to wire ring them with group a gasket and bolts and run 500+ all day long

cossie4i+

iTrader: (15)

Mine is wire ringed and a GrpA with standard head bolts.

Knocking on 480bhp, on a cool day lol

Steve

Staffi

iTrader: (1)

Steve, did Tony wire ring yours then??

rsmark86

iTrader: (3)

ment to be the best for 205 blocks

ive got 200 block in mine but uses the wrc gasket

Staffi

iTrader: (1)

Did the old RS500 Touring caes use Group A HG iirc??

cossie4i+

iTrader: (15)

Nope.

Was already done before it went to him.

Steve

JonnyBravo

I reckon a GT3076r would sort one out

v man

i was 17 back then

30 now

so not childs play for 2nd car

cossie4i+

iTrader: (15)

LOL

Steve

Rsmat

iTrader: (2)

ive got the tool for wire ringing the blocks..Its easy.

v man

we have heard about your tool

small
pointy and
sharp

lol

Roosie

iTrader: (8)

205 are good blocks I ran 440bhp for years and it still goes now no problems.
I think when you get to 500 then start building a new block

Rsmat

iTrader: (2)

Nice 1 pal,,,

robrs2

Most blocks are cracked during the building of the engine. Something that gets no thought at all is installing the head bolts. Doesn't matter if its bolts or studs.
Hydraulic the bolt/stud in the bolt hole and it will crack the hole/block.
If the bolt hole has oil filling the space under the tightened bolt/stud as the engine warms up the oil expands and can agin crack the block.
One more is if the bolt/stud is thread bound in the hole. i.e. the bolt/stud is too long for the thread in the hole. Your not tightening the head down just splitting the bolt hole and block.

Karl 3dr

iTrader: (9)

I must have been unlucky with mine because it cracked around a headbolt when i was only running 24psi on a T34.48, it fired a core plug out of the side of the block underneath the exhaust manifold which i later found in the osr trailing arm when i was fitting new springs!!

LHD220Turbo

iTrader: (4)

twisting of the block is what i have heard

m_nettleship

Would it not be down to maybe wich engineers they been to over the years?

Wud a block crack easier if bored to say .5? Maybe sometimes they get bad rep cos people bored them out to mutch! or in a incorect way! or liners fitted wrong.

Rsmat

iTrader: (2)

Valid point matt....did yours run 205??

m_nettleship

yes, but the engineers didnt step the liners once, and all 4 fell quarter a inch, on m1 at 90mph.

Rsmat

iTrader: (2)

Gutted mate.

KSA-Cossie

iTrader: (4)

You'll sell it before you fit that gt30 anyway uncle Pete.

tabetha

Exactly right, the stud MUST be of a length so the shoulder of the stud sits in the slight recess in the block, sometimes this means trimming a few mm from the end of the stud, the holes must be tapped to clean the threads so as not to cause any false "seated" feeling and the congealed oil in the bottom of each hole scraped out.
Both the 200 and the 205 block are VERY wobbly designs, if bored without a deck plate they can be rendered scrap, but a fair few places don't use deck plates when boring.
There's many 205 running group a gasket without wire ringing at 500 + on oversize pistons.
tabetha

SteveB

iTrader: (3)

My old 2wd Saff had spent it's entire life either STD or stg1.... When I took the head off at 150,000 miles it was fooked. Cracked around head bolt holes 3,4,7 and 8 in a big way.


Steve

cossie4i+

iTrader: (15)

What !!!!!!!!!!!!!!!!!!!!

Steve