Car went to local garage around 3 weeks ago as i thought my compressions were low and i'd come to the conclusion that my rings were shot after running very rich for most of my tuned engines life... so i went armed with new set of rings and thought maybe the bores may have needed rehoning as borewash may have took place....

How wrong I was!

Engine is scrap after only 6000 miles!
Head is beyond repair (which was polished ported and balanceshafts properly removed)
forged pistons ! Little bits of metal missing on the edges of more than 1 piston.... some serious detonation took place at some stage in its short life!
Needs rebore so will be going upto 84.6mm pistons now!

Basically this is a warning to all the latest budding tuners who just think you can buy all the uprated parts and sling them together and away we go! Wrong!
All this polish and porting.... C&B cams... Wossner pistons... are nothing without the correct "Mapping"!

I can only remember a window of about a month where i was ever lean.... i was running a map which required a 3.8 fpr but i only had 3 bar one installed.... had it dyno'd and yes it showed i was lean but not stupidly??
anyway after that month i installed the 630 injectors i'm currently runnin in preperation for the visit to Flea...
anyway about 2 weeks later my coolant hose burst which also caused my head gasket to go.... Joy!

So flea was on hold while i had the head gasket sorted.... when i got car back i decided to compression test it before making the journey down to bristol and got some seriously low reading but i was encouraged by more than 1 person to carry on with the mapping and that hopefully with the right fuelling finally my compressions may come up a little due to the bores/rings "Carboning up" over time? (don't really understand this?)
Flea mapped car anyway and car ran what i thought was fine.... but i just wasn't happy with the low compressions..... this is when my local garage investigated 3 weeks ago... gutted!

The funny thing is from the time of the headgasket going to now the car has covered no more than 350 miles!
So either the place that did the gasket ignored the damage and rebuilt or (what i think) some sort of bodge took place where the head was never even removed????
so when engine was cracked open a few weeks ago i'd have thought that the relacement Group a spesso head gasket would have looked quite new to say the least..... no! it was absolutely obliterated! i told the guys at garage that it had only done 350 miles and they weren't having any of it!
Am i right in thinking detonation only takes place when running lean??
It cannot detonate when running rich?
if this is correct then the damage was already there before headgasket went and it has only ever been rich since the head gasket was "changed" up untill flea mapped it properly..... flea can confirm this as he did a fuel trace on my car before mapping it i believe?

anyways engine is with a place called MJA engineering which is based in bromsgrove.... they are awaiting a replacement head which i'm picking up from Pete (moderator) tommorrow.... then work will commence!
I asked if my new head would be set up like my old one regarding removal of balance shaft, porting etc
He replied it will be much better than my old set up which he wasn't impressed with one bit...
Car should be truly Evil when rebuilt.... also upgrading turbo and oil cooler then back down to "The Fleameister General"! Aiming for a top 10 spot!

Nick (sorry for waffleing on)

Basically this is a warning to all the latest budding tuners who just think you can buy all the uprated parts and sling them together and away we go! Wrong!
All this polish and porting.... C&B cams... Wossner pistons... are nothing without the correct "Mapping"!

Yep Very true


Am i right in thinking detonation only takes place when running lean??
It cannot detonate when running rich?

'Fraid not. Too much ignition advance, or hotspot (such as an overheated spark plug) can also cause detonation no matter how much fuel is thrown at it.

Bad news Nick

I guess you have to make a call on the head gasket saga, as KJ has said the det could have happened after the gasket was done, but were you running up until the flea map, the same chip you had been running for the first 6000miles, if you have it is pretty unlikly it all happened in the last few miles before the remap

Anyway - your call on if it's worth investigating

onto the new build, are you going to use wossner pistons again? and on which rods? I can't recall if you are still running OE but if you are and looking at top 10 power output nows the time to change them.

Nick, I will give you a link (as I don't have it handy) to a intersting read on GC's forum about the 16vt inlet manifold, he is having problems with flow on the grale manifold - see his thread, which is already much better than the coupe 16vt design

Dink and I are looking at some options but won't hijack your thread.

and which turbo have you decided on?

here's the link in a new thread

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=1002109#Post1002109

Sorry to hear that. Until the engine is dissembled and inspected properly you will have no idea of the exact cause as it could be a number of issues especially causing of det (You may never find the exact cause). Mapping is a factor but only a factor anything could have caused a chain of events. I've been there done it and got the T-Shirt as sure many on here have been. All I can say is you will learn a lot from this and hopefully make no mistakes the second time round. I hope it works out for you as it’s always sad to see an engine go pop especially after a few miles.

nick who did the original build ..i am looking to get mine done after finding no2 at 70psi..but its hard to find someone good that knows there stuff but doesn't charge silly money..i have rung a few different builders one wants 3k+ to supply fit forged ,rebore,balance and flo head another wants 2k thats a big difference..one was 150 for the rebore the other 100 the dearer one said 250 to balance it the cheaper one said £60!! poss a few quid more if he has more messing than he expects so who is going to do a better job? its a lottery!..i know nothing about either so am not able to find anyone thats had work done ..who are you going to for the rebuild?
does anyone know a good place to have it done?

I said in the first thread dude.. MJA engineering!
http://www.mja-engineering.com/

been roughly quoted 1900 thats with supplying wossner pistons! (& with 12 month guarantee)
going to drop head of tommorrow hopefully so will get final price and have a chat...
maybe able to get price down a little with the introduction of the word CASH dropped into the conversation... lol

nick

God you were up late when you wrote that post!
coupe causing sleepless nights? i know all about that!

Nick

you got that right! i have been spending hours trying to sort it all out ..it's cost me days of work i had to drive to rotherham last night to pick up a van i had bought ..at 10pm !as if i didnt collect he was letting someone else have it..got home and carried on trying to find out/sort out what to do next...being well over budget already the prospect of a 2k+ rebuild is giving me sleepless nights..
are you happy to say who did the original ? did mja come recomended or was it just a local find?
i missed the original mja link as i had my eyes propped open with match sticks they give you two long blind spots

A guy called don laughlin did my first rebuild, i have no issues with this guy at all he did a good job for me and he is quite well reknowned round these parts...
this MJA have come highly reccomended tho by the place that took my engine apart 3 weeks ago!
they can't prais them enough and are prepared as i said before to give me a 12 month guarantee once they put the engine back in.... obviously they trust his work to make this guarantee!

Nick

Well I think Nick you were probably told to have a proper map done so no suprise really. You mention balancer shaft and head in the same sentence but obviously you know the balancer is in the block??

Too much heat and too much pressure will cause detonation that all you need to know its not just A/F ratio although that is a major player, inlet temp, boost pressure and end gas are few of the other factors.

At least now you have Flea who can get a much better tune for you, build that idea into your plans.

rich