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chip

Well, Ive been out today in the nova, with the boost wound up to finish off the mapping see how it went in preperation for going back onto the rollers for a final power figure next saturday when im meant to be renting the rollers again at mtech.

Have increased boost from the 1.55 bar to 2.1 bar, and fuck me it was going well, in fact so much so that there is NO way I would ever want to use it like that on track anywhere other than a bloody long straight (it was a big dual carriageway I was using it on and even there it felt fast!)

Came back home after a really good session out just enjoying driving it on a dry day at last, its handling SO much better now, ive altered the front suspension to give me more caster which seems to have worked well, and I was just generally over the moon with it.

When I left it idling to cool down though, I noticed that there was a bit of steam coming out of the exhaust, which was obviously a very worrying sign.
Compression tested it, and 2/3/4 were all perfectly on 11, exactly where they always are, but number one was up on 13, so I feared it had done the head gasket.
Me and gary ripped it apart figuring that if we could get it apart today, get my old man to get the head skimmed in the week and get a new gasket off steve we could get it all back together on friday ready for the rollers on saturday.

The head gasket looked mint though, no signs of any problems at all, so I started inspecting the head very closely, again no signs of any problems, so I finally turned my attention to the block, the mating face looks perfect, but when I wound that cylinder number 1's piston down the bore and cleaned the bore off very carefully, I can just make out a slightly darker coloured wiggly very feint line about an inch long, which can only be one thing, a crack!

Game over for me for a while until I decide what to do, no point just rebuilding it exactly the same as obviously I am almost certainly going to run into the problem again on another block if I start using it as hard.

Im not aware of anyone using one of these engines for anything other than short bursts drag racing at this sort of power level (must have been well over 500 judging by how much faster it was on the 2.1 bar setting than on the 1.55 bar setting that made 457bhp) so I need to decide if perhaps I need to be using a different engine instead to get this power, or accepting running less power to prevent me killing another block.

VERY bad day sadly!

Looks like the snotty old clio is going to have to get dragged back out for bedford on the 20th now.

Might see about just putting a standard bottom end into the nova and just run at a bar of boost or something in order to just get it out and get some seat time so I can work a bit more on the handling.

Will have a go at getting a picture of the crack, but TBH its just such a tiny little line I suspect I wont be able to get the camera to pick it up even on the macro setting.
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Under 400bhp makes baby jesus cry.
(so my boost leak at the jamsport day must have had him sobbing like rich j williams watching a chick flick)

www.totalvauxhall.co.uk

Nova - 457bhp - Mid Engine - RWD - GT35 - Autronic SM4

fennyLET · Posted: Sat Jan 30, 2010 9:03 pm Post subject:

Unlucky that one...

What has made it give a higher commpresion?
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chip · Posted: Sat Jan 30, 2010 9:05 pm Post subject:

GAZ`D · Posted: Sat Jan 30, 2010 9:24 pm Post subject:

that is not good but got to be worth building it back up with another block as it could well be just a duff block

what bore size are you on mate ?

i do find it rather ironic that so much money is spent on expensive parts by you and others only to find that the second hand block designed to take 200 bhp ish should let you down
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djbrowney let · vauxsport.com Joined: 27 Mar 2008 Posts: 931

are you running oversized pistons chip ?

dosnt sound very good at all, but on a good note at least it didnt completly shit its self and destroy all the money you have spent on the engine !!!

chip · Posted: Sat Jan 30, 2010 9:28 pm Post subject:

chip · Posted: Sat Jan 30, 2010 9:29 pm Post subject:

djbrowney let · vauxsport.com Joined: 27 Mar 2008 Posts: 931

very lucky PMSL

im sure i read on insane sweeds thread over on mig the bore thickness can be anything from 1.5 to 0.5 mm differnce (will have to check the size) dosnt leave you a lot after a rebore Cry

sbd16v · Posted: Sat Jan 30, 2010 9:33 pm Post subject:

such a shame as you were just getting the the point where you would have said fuck it thats enough lets have fun

well the good news for me is im getting less woried about my engine lol
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chip · Posted: Sat Jan 30, 2010 9:39 pm Post subject:

djbrowney let · vauxsport.com Joined: 27 Mar 2008 Posts: 931

hindsight is wonderful thing PMSL

chip · Posted: Sat Jan 30, 2010 9:47 pm Post subject:

Browney, yes mate!

20/20 vision when looking backwards.

Ultimately though, I suspect that I just need to decide that based on having now driven my car with engines making roughly
150
280
330
400
450
500+

That the right amount of power for it is probably around the 400-450 mark and just go down to a smaller turbo which means that I can also have massively improved spool over what I get on the GT35R at the moment!
_________________
Under 400bhp makes baby jesus cry.
(so my boost leak at the jamsport day must have had him sobbing like rich j williams watching a chick flick)

www.totalvauxhall.co.uk

Nova - 457bhp - Mid Engine - RWD - GT35 - Autronic SM4

sbd16v · Posted: Sat Jan 30, 2010 9:50 pm Post subject:

on a plus point we might still need the supertrap lol
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glove boxes FTW

specky · Posted: Sat Jan 30, 2010 9:53 pm Post subject:

am gutted for you... i cant belive its broke on you Sad

it makes me think about leaving mine alone now am thinking 2.5 bar of boost maybe too much to ask for frown

sbd16v · Posted: Sat Jan 30, 2010 9:57 pm Post subject:

i would not be surprised if 2.1 bar on your 35 is getting on for the most power anyone has run in a let in the uk
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glove boxes FTW

chip · Posted: Sat Jan 30, 2010 10:13 pm Post subject:

chip · Posted: Sat Jan 30, 2010 10:15 pm Post subject:

dewismotorsport · Posted: Sat Jan 30, 2010 10:31 pm Post subject:

Gutted for you mate Cry

Can't give up on it though pick up a new block and keep going, I know you said your skint at the mo but why not have a clear out of some cars? I know you've got about as many as me PMSL

so must be able to free up some cash for the rebuild, or you'd be amazed how much money you've got lying around in parts Nod

If not EVO engine Nod

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chip · Posted: Sat Jan 30, 2010 10:36 pm Post subject:

If I went for a different engine, it would be a saab one not an evo one, the saab blocks are pisstakingly strong, they make an evo look like a toy, lol

I'm not giving up on the car mate, not at all!
Im just probably going to give up on chasing more power than I will EVER have a use for, im not into drag racing and on track wether its 400bhp or 500bhp will not make any real difference to my laptime as I wont be able to capitalise on the extra power anyway, and it will just break more boxes etc.

Whatever I end up doing with the nova longer term, it will be 400-450bhp only, that I'm at least 99% certain on.

I think for now, I will just chuck a standard LET engine in it (prob with some steel rods) and run it at 300-350bhp or so.

That seems a good way to have some fun in it
_________________
Under 400bhp makes baby jesus cry.
(so my boost leak at the jamsport day must have had him sobbing like rich j williams watching a chick flick)

www.totalvauxhall.co.uk

Nova - 457bhp - Mid Engine - RWD - GT35 - Autronic SM4

fennyLET · Posted: Sat Jan 30, 2010 11:11 pm Post subject: