If that’s truly the case, it really irks me that Audi would have chosen these guides as a spot to lower cost on the S4. I mean come on, they obviously knew they were vulnerable if they felt the need to make better ones for the RS4 and although I understand the RS4 is higher end, costs more, etc. why the freaking guides that require a major work effort to replace. No issues with the RS4 getting better internals but the guides?
You have to remember that these B6/7 S4s were a test bed type of car for the new technology so Audi was learning on the fly in my opinion. They had a much longer time to go back over things by the time that they came out with the FSI V8s in 2007. Also the FSI 3.2 liter V6 came out in 2005 right after the B6 S4 with a very similar design and it still had issues with the camshaft adjusters but more updated timing chain guides like the FSI V8s.
I believe that is it in this case Axel. That’s why we haven’t heard any cracked guides stories from RS4 owners, but plenty from B6/7 S4s. Newer engine, stronger internals, in a way I guess they learned from their mistake or maybe just wanted a sturdier designed guide since RS4 pushes more power. Pretty much what Jimmy said. I wonder if JHM has looked into this, Jake?
Sorry for the threadjack 65vetteC6
Great pictures and documentation on the RS4 engine. I haven’t seen any good pictures of many of the internal parts before this thread. Seeing some of the differences between the S4 and RS4 blocks makes me want to skip building the S4 and jump into a stronger, higher revving platform with direct injection.
This whole timing guide situation sounds eerily familiar to the Infiniti disaster in the early 90’s. The timing chain guides in the 1990-1992 Q45s with a pretty impressive V8 were all plastic and cracked. Revised models in 1993+ had a metal backed guide with a plastic contact surface. I tried to find some good pictures comparing the original vs. revised designs but struck out.
The black plastic guides on the S4 look almost identical to the RS4 ones. I know the timing set-up overall is very different, but would it be possible to throw the RS4 ones in? I am sure JHM has tried/thought this out…any input? I have about a month until my car goes in for timing service.
This isn’t the first time the block codes have left people scratching. I was getting scrap motors over time to cheaply get a spare S4 motor. I found several miss matched. I read about the markings as well but I think all mine were long gone before I looked at them.
http://tapatalk.imageshack.com/v2/14/11/19/2ae504dbef1c9d4b45415a1f3e426bea.jpg
It was an expensive week for tools, picked up this bad boy, .00005" accuracy, and a new extended jack. To clarify a little bit of my previous posts, the block had GGGGG on the sides, this stands for yellow bearings. The Crank was label GGGBB or 5-Yellow 4-Yellow 3-Yellow 2-Blue 1-Blue. I decided to check out the bearings, 5-3 had the same numbers, and 1-2 had the same so I would say that is a confirmation that the crank markings were correct. All of this is technically irrelevant but I feel it is good to know as a starting point. Got measurements off the crank all between 64.965-64.958 which per Ebahn puts them as blue bearings. This would make sense since the crank has a little bit of wear already. Journals 1 and 2 were on the lower side of the of range, again backing up the use of two different beatings. So looks like Ill be going with Blue.
Now, on to the rods. Crank was marked GGGG-YYYY, threw me off at first but after a little reading, the first 4 are bearing size, second 4 states weather its narrow or wide. And yet again audi likes to make shit complicated. R= Red/Yellow G= Yellow/Blue and B= Blue/Blue. I think this might mean that they mixed bearings on the rods, blue on the top yellow on the bottom for example. I was chatting with ECS a bit and they said they have seen that before. Hoping JHM can confirm but they haven’t gotten back to me yet, must be busy.
A bit of elucidation would be appreciated.
Fair enough, Audi specs are to 3 decimals in mm. Thats a pretty fucking accurate measurement, not something a typical caliper can handle. This has accuracy up to +/- .00005" or .00127 mm from 2-3". So basically I can get accurate enough measurements to determine the bearings. I can get even more accurate if I had a zeroing block made to like 64.5 mm but the 2" one provided should be good enough.
Thank you.
I’m jealous of your measurement instrument, even though I’ll likely not need one.
I’ve built my share of motors, but I never had one like that.
Have you ever seen them use different sizes from top to bottom on the rods?
I have seen all kinds of sruff and all kinds of miss matched wrong stamps. I don’t specifically remember miss matched on the rods but I wouldn’t think it’s impossible. I will check and get back to you.
Yes. I saw mixed bearings different top and bottom. But what’s weird is it wasn’t every one.
Well, lets see update time. Been trying to figure out this whole bearing thing. ECS has all main bearings listed on their sight but when I inquired they came back and told me their Audi source said they had all been superseded by 079105561H (Yellow). Spoke to Z at JHM as well, they seemed to be able to get pricing on all the bearings but he set me up with what came with it from the factory, which might not be the “best” option based off of the measurements I gathered. I then checked out GAP since they have excellent pricing and shipping, again different information. Under the RS4 they only list 079105561G (Red) which is the largest bearing. If I search by part then they do carry the other colors but only list them for the R8 and the S5 ???.
So a recap:
ECS says I can only get 079105561H
GAP only lists 079105561G under the rs4 section
JHM was able to get pricing on everything but no one has really been able to give me any advise on following the Bentley manual or throw what came from the factory back in.
Realistically I can probably run what came from the factory and not have to worry. The life span might be 100K miles compared to 150K because its a little looser but if the radial tolerance is in spec, we’re good IMO. My current plan: Order a bunch of colors and check the clearance with all blues. If they are too tight I will step up to 1 blue and 1 yellow. Cant wait to deal with the rod bearings.
I don’t think anyone from jhm would be able to advise you without actually having the block. They can sell you what you need but if they aren’t building it it’s hard to advise you on what to do. Giving advice on something like that is something I think anyone would be reluctant to do. A high rpm motor you start to run into bigger issues if things are off.
Eh, only advice I was really seeking was to go by the bentley manual on picking bearings based off their current measurements compared to just throwing in the same bearings that were in from stock, but I know what you mean.
I think picking bearings out of a book is a bad idea no matter which way you look at it.
If you want to do it right you need to measure the bore and crank and decide what size bearings you need.
I am not sure how Audi does it but Ferrari has different size bearings. Each size has a part number and 2 colors. The colors don’t have a part number them selves. You have to order the part and request the color, or go to an aftermarket bearing.
Mix matched colors are common. 2 bearings that are different colors were manufactured to the same spec one could be over and one could be under. They use colors to make it easier on them when assembling the engine. If the bearings are mix matched, you will always find the colors to match on the same side. Example: greens on block side, reds on cap side.
Disregard my post,
I tried to edit it, but I guess you can’t edit posts here.
I didn’t understand what you were asking and I also didn’t know that audi uses colors in-place of actual sizes.
Ferrari uses sizes and then colors to determine variants in each size.
Not at all the same, good luck!
You can edit after you make a certain amount of posts.
The audi system of bearings is confusing
The black plastic guides on the S4 look almost identical to the RS4 ones. I know the timing set-up overall is very different, but would it be possible to throw the RS4 ones in? I am sure JHM has tried/thought this out…any input? I have about a month until my car goes in for timing service.
This thread has been dead for a while, but the pictures helped me make a comparison between the BNS chains, and the BHF. The BNS engine uses the same upper and lower metal guides as the V6 BKH engine. The parts are 059 109 469 E and F. They look like they’ll fit into the BHF engine, so for about $100 shipped, it seems like a worthwhile experiment.