ZRP Forged Conrods
Discussion
As I said, I am/was not seeking to lay blame solely at ZRP's door. Simply passing on my experience and comments made by the engine builder. As you rightly say, the overheating most likely started a chain of events. That said, the builder also stated their was a flaw with the little end / oil way but that is just his opinion I guess?
Apologies if my lack of knowledge is a frustration but my hope was that I might learn something through discussion.
Apologies if my lack of knowledge is a frustration but my hope was that I might learn something through discussion.
As I stated earlier in the thread, I was not seeking to lay the blame of failure solely with ZRP and there were other contributing factors.
I, like many other people, have to rely upon the knowledge and skills of an engine builder. Unfortunately, in my case there was a breakdown in communication and certain concerns were not understood until too late in the day. Initially my understanding was that the builder had said that although not overly impressed with the quality of the ZRP rods, they appeared to go together OK and the only thing of note was how heavy they were, in comparison to the OE rods. Having spoken to him in person (after the failure) it appears he had concerns over the thickness of coating in the small end, the variation in material thickness along the length of the road and the oil way size. As I say, unfortunately these concerns did not reach me till it was too late, or else I would have taken his advise and not used the rods. I would have taken that decision based upon the fact I am paying the guy for his expertise and to simply ignore it would have been foolhardy.
It was his opinion that the overheating possibly contributed to the failure of the big end, although there was also concerns about thickness of internal big end surfacing and its wearing through before the bearing eventually spun.
Either way, there were several factors at play. For whatever reason though, had I not misunderstood third party information, I would have taken the builders advice and not used the ZRP rods.
In relation to the Arrow rods however, initial inspection shows the quality of finish far exceeds the ZRP. Obviously the checks that Mignon kindly wrote about would need to be employed to confirm their being so. Just the quality of packaging and the overall finish of each individual rod hints at a far better quality of product though. (I realise this is cursory inspection by eye and not how rod quality is checked!) I also bought my rods directly from Arrow so am pretty confident that they're genuine.
In relation to your final point though, it could be that a better quality rod would not have suffered a failure brought about by the short overheat? In which case, spending the extra on Arrow rods would have actually saved me several £k's in rebuild costs. That said, if my sister had balls she'd be my uncle. As I say, there were several things that led to the ultimate failure of the big end and no single thing I would seek to lay at the door of ZRP. Any questions over their (ZRP) quality are simply the opinion of the engine builder I used.
I, like many other people, have to rely upon the knowledge and skills of an engine builder. Unfortunately, in my case there was a breakdown in communication and certain concerns were not understood until too late in the day. Initially my understanding was that the builder had said that although not overly impressed with the quality of the ZRP rods, they appeared to go together OK and the only thing of note was how heavy they were, in comparison to the OE rods. Having spoken to him in person (after the failure) it appears he had concerns over the thickness of coating in the small end, the variation in material thickness along the length of the road and the oil way size. As I say, unfortunately these concerns did not reach me till it was too late, or else I would have taken his advise and not used the rods. I would have taken that decision based upon the fact I am paying the guy for his expertise and to simply ignore it would have been foolhardy.
It was his opinion that the overheating possibly contributed to the failure of the big end, although there was also concerns about thickness of internal big end surfacing and its wearing through before the bearing eventually spun.
Either way, there were several factors at play. For whatever reason though, had I not misunderstood third party information, I would have taken the builders advice and not used the ZRP rods.
In relation to the Arrow rods however, initial inspection shows the quality of finish far exceeds the ZRP. Obviously the checks that Mignon kindly wrote about would need to be employed to confirm their being so. Just the quality of packaging and the overall finish of each individual rod hints at a far better quality of product though. (I realise this is cursory inspection by eye and not how rod quality is checked!) I also bought my rods directly from Arrow so am pretty confident that they're genuine.
In relation to your final point though, it could be that a better quality rod would not have suffered a failure brought about by the short overheat? In which case, spending the extra on Arrow rods would have actually saved me several £k's in rebuild costs. That said, if my sister had balls she'd be my uncle. As I say, there were several things that led to the ultimate failure of the big end and no single thing I would seek to lay at the door of ZRP. Any questions over their (ZRP) quality are simply the opinion of the engine builder I used.
Edited by e30m3Mark on Saturday 9th December 23:41
Edited by e30m3Mark on Sunday 10th December 09:53
Were it not for the fact he (the builder) had expressed concerns before using the ZRP rods, I would most likely have agreed with you. As I said earlier, a breakdown in communication led to these concerns not reaching me. If they had, I simply wouldn't have risked using them whether those concerns were misplaced or not.
What I had noticed, the first time the car was driven on track, was the increased oil temp' from before the rebuild. It wasn't to the point where I had concerns, given that a new oil pump was fitted along with a baffled, increased capacity sump but before then oil temp' had always been consistent. With hindsight, is it possible that the big end had started to deteriorate and develop heat?
Whilst I think, this is a quote from an exchange with the engine mapper, who was there when the engine was stripped.
''There is no sign of detonation at all, even where the pistons have touched the head as the big end clearances went wide, indicating a good margin in my settings for the extreme conditions that occurred. The skirts are scuffed as expected, but not severely enough to have initiated the failure, that's limited to the big ends, which appear to have high spotted, probably because of uneven rod shape, subsequently worn through the surface and spun readily as the radial clamp force on them appears to have been inadequate. Assuming the oil supply has remained constant, that is simply down to the quality of the rods, which I think someone this end should have advised you against using.''
Just for clarity, this is just a discussion which I am trying to learn from. As I have said (a couple of times at least) I am NOT looking to lay blame solely on the ZRP rods. It's just a discussion and the rods, amongst other things, were just one factor.
What I had noticed, the first time the car was driven on track, was the increased oil temp' from before the rebuild. It wasn't to the point where I had concerns, given that a new oil pump was fitted along with a baffled, increased capacity sump but before then oil temp' had always been consistent. With hindsight, is it possible that the big end had started to deteriorate and develop heat?
Whilst I think, this is a quote from an exchange with the engine mapper, who was there when the engine was stripped.
''There is no sign of detonation at all, even where the pistons have touched the head as the big end clearances went wide, indicating a good margin in my settings for the extreme conditions that occurred. The skirts are scuffed as expected, but not severely enough to have initiated the failure, that's limited to the big ends, which appear to have high spotted, probably because of uneven rod shape, subsequently worn through the surface and spun readily as the radial clamp force on them appears to have been inadequate. Assuming the oil supply has remained constant, that is simply down to the quality of the rods, which I think someone this end should have advised you against using.''
Just for clarity, this is just a discussion which I am trying to learn from. As I have said (a couple of times at least) I am NOT looking to lay blame solely on the ZRP rods. It's just a discussion and the rods, amongst other things, were just one factor.
I didn't have the full story from the outset so any drip feeding hasn't been deliberate.
The overheat was coolant. I merely noted an increase in oil temperature (compared that that seen under similar conditions on an earlier occasion). The sump fitted was one developed specifically for the s14 engine, with increased oil capacity and baffled against surge. I know you said you weren't psychic and your assumption in relation to the sump certainly confirms that fact.
The oil pump was also in good order and there was no hint of a drop in pressure.
I am not able to give exact readings (in relation to oil temp and/or pressure) hence my decision to swap to a Stack dash display in future which records these readings.
I do not have any photos yet, hence there not being any posted here.
Anyway, thanks for your input.
The overheat was coolant. I merely noted an increase in oil temperature (compared that that seen under similar conditions on an earlier occasion). The sump fitted was one developed specifically for the s14 engine, with increased oil capacity and baffled against surge. I know you said you weren't psychic and your assumption in relation to the sump certainly confirms that fact.
The oil pump was also in good order and there was no hint of a drop in pressure.
I am not able to give exact readings (in relation to oil temp and/or pressure) hence my decision to swap to a Stack dash display in future which records these readings.
I do not have any photos yet, hence there not being any posted here.
Anyway, thanks for your input.
Edited by e30m3Mark on Sunday 10th December 12:59
stevieturbo said:
datalogs of oil pressure during the racing ?
It was a few laps of Brands Hatch @ Deutschfest Steve and unfortunately I don't have anything relevant available. I merely noted that the old analogue gauge was reading higher in comparison to an earlier event in similar conditions. Ive said:
Your sump kit sounds VERY suspicious. Is this a tried and tested sump set-up? If you were the Guinea pig for this sump, then go figure.
This is my suspicious sump. I think they have sold a few of them.https://store.vacmotorsports.com/vac---s14-megasum...
There have been no pictures because I don't yet have any. The builder is some distance away and my having pictures won't change an awful lot about the situation.
Obviously anyone using ZRP rods here is going to be a little defensive but, as I have said several times now, I am not seeking to lay blame solely with the rods. In fact, I'm pretty sure I said there were accumulative factors that ended with the spun shell. That said, given that I have spoken to both the builder, the chap who mapped the ECU and my mechanic, all of whom expressed concerns over the quality of the ZRP rods, I feel perfectly justified in posting my opinion.
Oh and in the quest for my giving the ''whole story'', my engine didn't fail on track. I was on the A30 heading up to Silverstone and had been sat at between 4 and 4.5K RPM for a little over an hour and from memory I don't recall any high G corners. Neither oil pressure or coolant temp' looked untoward and were certainly within normal parameters. The oil and filter had been changed the day before using Shell Helix 4-40 Ultra. The builder has also built many s14/2.5 and s14/2.5 for competition and had we spoken in person, prior to his fitting the ZRP rods, I would have taken his advice. As it was, a third party told him I wanted to use the ZRP rods as my budget was exhausted and so he didn't think there was an alternative. These were unfortunate circumstances and one's I accept as being my own fault.
CarsOrBikes said:
OP you do keep saying you're not laying blame at ZRP's door, but you already have, and again just a couple of post ago. .
I said solely at ZRP's door. As I also said, there were at least 3 people involved to some degree, who questioned the quality of the rods. There wasn't a coolant leak. The alternator mount on an s14 is rubber bushed and this failed, which meant it threw the water pump belt. The engine wasn't run for long and coolant temp' peaked at 125 deg (I recall that from the info on the ECU) but I think that most likely started a chain of events where the rod quality played a part.
Mignon said:
disputatious stuff
Or maybe it was simply the quality of the rods was such that one failed, where a rod of known quality would have been fine? Just out of interest, do you mean under filling that sump that yesterday was of questionable design and most likely led to oil surge?
Edited by e30m3Mark on Monday 11th December 09:38
Mignon said:
I'm wondering why we've been chasing our tails for 8 long pages on this ever changing story.
The story has remained the same. Mainly due to it being an actual event and not something conjured from fresh air.Mignon said:
My sympathies are now swinging back to the engine builder because you must be an absolute nightmare to deal with if you can't get a story even remotely straight after so long trying or make your mind up about what it is you actually want.
My engine builder is perfectly happy, as I do not struggle with interpersonal skills or communication. He has a good reputation and I am confident in his abilities. This is a forum, a place for discussion and there has been only one individual who hasn't remained respectful and open minded throughout the past 8 pages. Mignon said:
It's like getting blood out of an effing stone from you unless this is really some of weird trolling situation. First it apparently overheated on track so we assume this is a hard use track day failure, then the overheating is oil not water, then it's water again but the oil temperature was something different, then you mention the new sump, then suddenly it actually failed pottering about on an A road not a track day, oh and the oil had just been changed and after the mapper says "pistons" plural hitting the head so we assume several or all four bearings failed it's now just one of them but you never thought to mention that in the first place.
A list of assumptions, all of which were made by you and you alone so no point bleating about them. In fact, there is probably a lesson in there for you. Mignon said:
This ain't normal even for some of the bizarre threads I can recall from 10 years in here and you my friend are weird. I'm out. Good luck with it.
I'm guessing the irony is like an aeroplane?Somehow I don't think you'll be missed. Bye!
Meanwhile, back in the real world.
227bhp said:
The rod has failed in some way, it was the effected and not the cause, that's the whole point.
This.stevieturbo said:
Soo...back to simplicity.
How did the ZRP rods measure before installation...and how do they now measure up after the engine failure ? ( not rod failure of course, engine failure )
And you say you seen a coolant temp of 125degC ? Pretty sure that's f
ked by anyones standards and if pushing hard oil temp will be higher.
I'll mail the builder and see if I can get some actual data / measurements.How did the ZRP rods measure before installation...and how do they now measure up after the engine failure ? ( not rod failure of course, engine failure )
And you say you seen a coolant temp of 125degC ? Pretty sure that's f
ked by anyones standards and if pushing hard oil temp will be higher.Yes, the coolant peaked at 125 degC but I wasn't on track or even pushing on. In fact, it happened on the A30 at almost the same spot as the eventual failure. Maybe it just doesn't like leaving Cornwall?
Edited by e30m3Mark on Tuesday 12th December 10:23
Edited by e30m3Mark on Tuesday 12th December 10:24
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