As part of my ABF 16VT Conversion, I decided to go for some Forged conrods. I stayed away from the Chinese / Ebay Turbo`s after reading several horror stories of them being made of low quality materials and failing, taking the engine with them. Lots of research online and I couldn`t find similar stories about the Forged rods. I could have gone for the slightly larger VW 2e rods, but decided the Forged ones would be a better option... I went for the VMI Forged ABF Rods complete with new big end bolts. Once fitted, the difference between them and the stock rod was obvious. After rebuilding the engine with the new rods, I ran it in, did Rockingham then Bedford where I had a piston C clip failure. Whether this was `one of those things` or builder error, I still don`t know. I was concerned there could be an issue with my conrods. If the little end bore wasn`t parallel to the big end, there could be sideways force on the gudgeon pin which could have caused the failure. I didn`t have anything more accurate than a pair of calipers, so I looked on google and found a local Precision Engineering Company. Gave them a ring, it`s not the sort of thing they usually do, but they were sure they could help. They did have was a vertical measuring machine. We measured pretty much every dimension you could think of, I took an OEM conrod along for comparison, the suspect conrod and one from another cylinder for comparison. Measuring the distance from the base to the top, bottom and centre of the gudgeon pin hole. Same with the stock rod After just under an hours measuring we concluded that: The holes are parallel to each other to within 0.0004" The holes are not parallel to the base of the conrod (where the caps bolt together) by 0.002" The gudgeon pin movement, with the pin centralised and max up/down movement measured on the OEM rod is 0.0015" The gudgeon pin movement, with the pin centralised and max up/down movement measured on the H rod is 0.0022" The H rods are 0.007" longer stroke (the distance between the crank and gudgeon) Both the H rods I took were within 0.0002" of each other on every dimension I`m very confident the rods are well within tolerance, not only of each other, but of the VW stock rod. Rebuilt another engine and it` been fine for a few months. I had a catastrophic failure at Goodwood.... Stripping the failed engine showed issues with the Conrod... I fished the conrod bolts out of the sump. General consensus seems to be that one rod bolt sheared putting massive stress on the other, which then bent, stretched and failed. The resulting inertia destroyed the rod, crank, block, piston, head, oil pump, intermediate shaft etc etc etc. These are the rod bolts on another cylinder. these are NOT ARP bolts, just look similar. Initially, I spoke to the seller and asked if he could supply a single rod, I still had faith in them and was just going to get some ARP rod bolts instead. After his reply, I decided not to bother... I`m now getting some Integrated Engineering Conrods with assistance from Toyotec getting them back to the UK with some other parts he`s ordering What I DO know is they were assembled properly. I used a very accurate, certified Torque wrench borrowed from work. Tightened exactly as per the supplied instructions and everything went together without issue. Was I just unlucky ? Are they good rods, but crap bolts ? Honestly, I don`t know. I haven`t found other examples of these failing, but I`m simply not willing to risk it. I had a few people suggest unknown Ebay rods/bolts weren`t a good idea. As I couldn`t find evidence to the contrary, I decided to give them a go. In hindsight, that may not have been the best idea I ever had....
Sorry to hear this after all the work put in after the last time I'm sure your right about the bolt I'd send him a link to this thread if it was me Edit any markings on the heads of the bolts?
Nige real shame post his email and well all give him what for lol That's the trouble with bolts with no marks I'm sure you'll know from work that ht bolts come in various grades When I have specials made I always ask for a conformity certificate I'll post a ht chart with torque settings etc when I've uploaded it to photobucket So here's the chart about bolts I use m20 x 12.9 in my machines and they still break causing lots of damage
Yeah, obviously very frustrating, but at the end of the day, it`s a lesson learned. I reckon, if bought and used with ARP rod bolts, they`d be OK, but by the time you`ve bought the rods and ARP`s, you may as well pay a little more for some proper rods like the Integrated Engineering ones that come with ARP`s anyway. Seller would do me a deal though. He would sell me another set, for 5 less than I bought this set for as a gesture of goodwill.. By then, his attitude and replies convinced me not to deal with him again.
Ive heard mixed stories like you say. I cant remember what companies but I believe some of the "brands" are also made out in china. I have heard of knock off ARP bolts with some of them- as far as im aware all the ARP bolts are traceable. There was a thread on another forum where the buyer bought some "chinese" rods and then checked with ARP the serial numbers which linked backed to the sale and showed they were genuine. Im assuming the extra weight of the aftermarket rod would have put a very high load on the knock off bolts.
With the cost of time, broken parts and aggro, it's cheaper to put pukka branded stuff in. Carillo, arrow etc.
Sorry to hear about this Nige. Would be interesting to do some testing on the surviving rods. I'm thinking specifically of the sideways flexibility of these versus stock ones (dunno how one might do this though?). I'm sure they're supposed to be stiffer in all directions, but it would potentially explain both failures if they weren't as stiff sideways.
Unfortunately I think it is one of those situations where you live and learn.... I know I have on more occasions than I care to remember! I will say one thing Nige great to meet Matt and you that day, your Golf is mighty impressive and bloody fast! I was very impressed just a shame I couldn't grab a spin out with you. Hope to see you at Brands in Dec and will have mine out on track.
That does backup my comments that the rods are probably OK but the bolts are the weak point. No, you said "All are made in the same manner and with the same machine". Anyway, I don`t want to get into an argument with you. I have explained what happened with my engine, I have NOT `blamed` the rods. I said I wasn`t sure about the rods but was unconvinced about the quality of the BOLTS.
You'll have to excuse me, but I do find 5 off funny, almost insulting and bad business practice. Goodwill is an essential part of any business.
It is about 5 off this demonstrates a lack of goodwill. I don't want to get into the technicalities nor is it strictly necessary, but you have to accept you've lost goodwill or you would not be here.
I'm not sure what all the fuss is about, you took a chance on a set of cheap rods and they broke, lesson learned. Personally I wouldn't put a part like that near my car, they are cheap for a reason.
gsi_tuning, Welcome to Club GTI. Whilst, unlike Nige, I would not condone replacing the properly DV'd and raced VW conrod with these unknown parts, tell us, what is the difference ( apart from the name stamping) with your rod kits and these ( pictured below) that can be ordered from China in bulk? Have you seen the testing and DV process? Or are you just repeating what is on the website?
The lighting is bad on the picture of that yield tested bolt, but its still clear that it's not the same bolt as supplied. It looks more like an ARP bolt to me.