Cracked Piston = Bad Tuning

[wreckedhead]

just to give some insight into what casue JETT to fail at the last WSID meet, after many weekes of waiting the engine is out and motor was stripped, not long after the bottom end was apart we found NO#5 piston cracked all the way down the side, and after taking the piston to many workshops all experts have decided and confirmed that the piston only cracked due to the TUNE being very very lean and detonation caused the piston to crack, after mentioning who had tuned the car last ( CROYDON RACING ) all but one person started laughing at me asking me why i was so dumn to take my car to them for tuning, not only did all but 1 tell me they are a waste of money, but I was also told by all 4 mechanics at 5 differnt places that they have NO or little idea how to tune a gtr power.

SO my conclusion is if your going to tune your car and have any doubts about croydon, avoid them at all costs, I have personally been and watched c and v tune my gtr on the dyo, and know that their tune is much safer and still ran the same power figures.

AS for croydons $1600 tune, i say good luck to thoise stupid enough like me to take it there in the first place.

Good luck...

[Miz_VL_Turbo]

not good to hear, have you taken it up with croydon at all?

[wreckedhead]

I wouldnt even waste my time arguing the point, what do you think they would say after i tell them its their fault i have to rebuild my engine costing in excess of 5 grand, they gonna laugh and hang up. So im just putting up a notice for people to know that Croydon are a rip offfff

[yogi000]

this is gonna be an interesting thread.

[williamsf1]

I can't see this thread lasting long... it is slightly worrying though....

oh and as an after thought, how about before this gets locked, you might post up the dyno sheet (latest one) with the AFRs on it....

if the tune is above say 12.5 : 1 yeah that would be in my books aggressive....

how many km since the last rebuild?

how much AWKW?

how many revs is it doing (max)?

Edited September 12, 2005 by williamsf1

[Abo Bob]

Everyone has a story about at least one workshop.

I know of a certain R34 GTR with a blown engine which was tuned the day before by C&V.

The fact is that we are pushing these vehicles to their limits. The reason why they have x amount of power out of the factory is because at that level the factory feels that the rate of breakage will be low enough to keep their reputation and bank balance in good shape.

If they pushed them as hard as we do then sure they would have 50-100% more power but imagine how many blown engines there would be.

[wreckedhead]

never been rebuilt, has 80ks on the clock, made 443kw@wheels, with C16 and nitrous 50shot, and max revs 8000grand

[wreckedhead]

Everyone has a story about at least one workshop.

I know of a certain R34 GTR with a blown engine which was tuned the day before by C&V.

The fact is that we are pushing these vehicles to their limits.  The reason why they have x amount of power out of the factory is because at that level the factory feels that the rate of breakage will be low enough to keep their reputation and bank balance in good shape.

If they pushed them as hard as we do then sure they would have 50-100% more power but imagine how many blown engines there would be.

<{POST_SNAPBACK}>

good point bob, but just to add on that my car has been tuned for race many times by Cand V and they ever pushed it to 100percent, always was on about 85 percent, even with A standard GTR fuel pump the car managed a 10.8 sec pass, now i got the 044 in and paid them 300 bucks to run a 4 meter length cable to the battery so it can have constant power i thought too myself, do you think these guys might be a little bit of a rip off. but hey its entierly my fault for taking it there and not sticking to where i know i was safe.

[siksII]

I wouldnt even waste my time arguing the point, what do you think they would say after i tell them its their fault i have to rebuild my engine costing in excess of 5 grand, they gonna laugh and hang up. So im just putting up a notice for people to know that Croydon are a rip offfff

<{POST_SNAPBACK}>

i know of multiple cars that have popped after a crUd tune, usually too lean and too much boost, post up a dyno sheet with your AFRs..

u cant post negative feedback on here naming names so the thread will be edited or deleted u might as well edit it yourself now..

and expect a million people to start flaming u too, since there are many who will not believe that for the 1200 they paid for a tune it could be less than perfect

[Beer Baron]

do you have a graph with the AFR. I recon 400+ kw atw was a bit much to ask of a stock motor though regardless of the tune. 27psi boost, C16, NOS, T88 don't neccisarily make a reliable package on a stock motor. regardless of the tune.

[Amaru]

It was a stock motor? Not overly suprised now, theres limits to how much you can push stock components before fatigue starts to set in.

Im in no way defending CRD, I have never used them so I cant comment. However I have seen some of their tunes and they have been alot more aggressive than most other workshops in Australia, which is how they get the extra power out I guess.

-- START EDIT --

On that note, the CRD tunes I have seen have still had a safety margin, its just been slimmer than most other workshops. I am in no way bagging their tunes, anyone who can get 400awkw out of 2530's on pump fuel should get some credit for knowing what theyre doing

-- END EDIT --

As has been said, youre playing with a highly modified engine, things are going to break. Horsepower comes and the sacrifice of reliability and vice versa.

Bad luck though

Edited September 12, 2005 by Amaru

[Blitz]

There are always 2 sides to every story I reckon

Over 400kw, with Nitrous on a stock bottom end - what were you expecting? Like Beer Baron said, if CRD supposedly tuned your car stupidly lean, show us the graph that confirms it. And more to the point, did you not look at the dyno graph when they tuned it and check the AFR's?

I will believe it when you post the dyno sheet, because I dont believe that CRD would push a car with a stock bottom end so far and not leave a safety margin

[T0nyGTSt]

this is gonna be an interesting thread.

<{POST_SNAPBACK}>

Yeh I'm about to sit back with a Cascade and a sammich and see how this one pans out.

To be fair to CRD, they tuned and built many a car... I'd say their success vs. failure rate is one of the better ones in Australia (the was that mob in Perth... what were they called??? RRT??? Something like that).

To be the devils' advocated, who's to say the engine was built properly?

Another thing is that other workshops will rarely say wonderful things about each other.

T.

[williamsf1]

ok to me that is wayyyyy too much power to expect to live, surely anything in the 400KW region is a short engine life, especially stock as you are implying....

5,000km would be lucky in my book....

AFRs would be nice, but I suspect you have just over cooked it...

[williamsf1]

oh and 80,000 unknown km? even standard engines on low (1 BAR) can bang out at that time....

sour grapes?

I see Jim is replying, so we will get the truth soon enough

[Blitz]

Oh, and when you tuned it with CRD, was it tuned with Nitrous?

[CRD]

Running on the rev limiter on a normal power f will cause fuel delivery to cut out!!.Did you mention your fuel system voltage issues previous to the vehicle being tuned.Why dont you mention that i strongly recommended to you that the need to have a nos rpm limit switch so that the nos wouldnt be turned on at very low rpm and cause a backfire and high rpm limit to prevent the nos running incase the vehicle runs on the rpm limit of the ecu.What about the thermostatically controlled nos bottle warmer that you were told you needed to prevent nos pressures varying from 700psi to over 1000psi,a whopping 30 percent variation at the nos nozzle (delivery to the engine).Why dont you add the fact that you picked up the car on friday nightthen on saturday when i saw you againi asked you about the cars performance and you mentioned you had tried it and it was fine.why dont you mention the fact you ran the car without nos on the first pass (low 11 sec run)next run you forget to turn on the awd and ran with nos staying on the rev limiter for sometime before backing off.Its all well and good to point fingers and lay blame to others,but unfortunately you only have yourself to blame.If i recall correctly all you wanted to do was run the car on sunday so you could then sell ti ASAP.(palm it off to some poor unsuspecting person)I also recall you personally bagging the shit out of some of the other shops you have dealt with in the past so i does not suprise me that you started a thread like this and yeah why didnt you/havent you approached us and show us the components you are referring to and tell us what you found.

Jim Souvas

CRD

Tech Engineer

[yogi000]

i think sometimes miscommunication between the tuner and client is one of the biggest factor of engine going bang!

once again straight from the horses mouth is always best!

[Beer Baron]

makes sense to me: stock motor + fuel cut type limiter + NOS + 27psi + holding car on the limiter during burnout = bad news.

Sorry that it's gone though wreckedhead. look at it this way mate, just build it up bigger and better.

[Blitz]

And the real facts become clear............

Sorry to see your motor blow wreckedhead, but given the information above it seemed like it was bound to happen.