The Road to Drag Week 2014 - May 18

[Drew Pojedinec]

The only midsized diesel I know of that uses a chain like this is a Cooper Bessemer.  It doesn't run in nearly that manner tho.
Here is one from our junkyard (we don't run them anymore)

[Cyclone03]

Drew I don't know the inside of any diesel just took  a WAG . Maybe something German.....

Anyway just talk, Jay needs another project prior to Drag Week like he needs a hole in his head.LOL

[Heo]

Jay Mercedes use chain on many Engines both Diesel and gas models
with a hydraulic tensioner from the Engine oil maby you can use some
ideas from there
The V8 from the 80s is a sohc and use a chain.
I have one but have never touched the Engine
it just runs and run.So i dont know how they
made the tensioner.
The later V8 up till late 90s is a dohc but is said to be the same Engine
exept the heads .
I have one of those to but never touched that one either
It have Electronic variable cam timing....If that give you some ideas

[Drew Pojedinec]

our 2005 VW passat TDI wagon had a chain driving the cam, balance shaft, oil pump, etc.

It is a horrible idea, we threw it in the trash and set the whole works up gear to gear.  270k miles later, life was still groovy when I sold the car.

[Heo]

Well i gues Mercedes know something that VW dont know then

[BruceS]

Jay,
Great stuff!  Never have seen a Cammer go together. After rasslin' that front cover on, do you have any concerns about alignment with the crank and front seal?

Thanks again for the excellent post.

Bruce

[jayb]

I'm not concerned, Bruce, because if it is out of alignment there's nothing I can do LOL!  Hopefully there will be no leaks there...

[Bullitt]

Nissan 3.5 V6 has a really long cam chain with plastic guides.  Then a set of smaller chains that drive the second set of cams.



Josh

[WConley]

Notice the elliptical chain guides?  That's the way it's done nowadays.  A chain setup will run 200K miles easily with elliptical guides and a hydraulic tensioner.  That's had me thinking quite a bit about improving the FE SOHC setup.  Just another project...

[machoneman]

The hydraulic tensioner is a wonderful idea, especially if a current OEM unit can be easily modified and adapted to the SOHC. Very interesting!

[cobracammer]

The hydraulic tensioner appears to be on the drivers side chain guide.  How exactly does that work?  Based off of Oil pressure at high speeds?  And with a SOHC, due to the route of the large primary chain, the tensioner would have to be located on the on the opposite side of the chain as it is shown in the Nissan (just due to how the chain is routed on a cammer?)  that would definitely eliminate the worry on chain stretch  :0)

[Drew Pojedinec]

Cool ideas on that nissan.  I like the hydraulic chain guides.

[cjshaker]

That was my point about the 4.6-5.0 engines. The elliptical chain guides play a major role in controlling the chain. A hydraulic chain tensioner would be nice for low maintenance (if there is such a thing on an SOHC , but not really necessary if it's adjusted occasionally. And it would be fairly difficult to accomplish. But the guides could be adapted even if only the nylon parts were used and bases for them were fabricated. The uncontrolled whipping action, or whatever you want to call it, leads to a lot of the wear. Ford engineers know this and that's why they designed them that way. That's also how they can get 7000 rpm 5.0s to last for 150,000+ miles.

That top stretch would be the toughest area though because of the minimal distance available to the top of the backing plate and cover. Not much room there.

[WConley]

Agree with the difficulty of the top stretch of chain on the SOHC.  It doesn't take much curve to get decent chain control though.  (I was at Ford when the first Modulars went on the dynos, and we got to see the chain drive development firsthand.)

BTW - On that Nissan, the tensioner is on the slack side (passenger side)  The elliptical guide on that side has a bottom pivot, and an oil-fed piston presses the top into the chain.  The doohicky on the driver's side is the water pump.

- Bill

[Cyclone03]

Hey Jay! Scrap Drag Week, we want to see an automatic chain tensioner for a SOHC, I'll never own one (or at least don't have plans to buy one) but dog gone it Drag Week is just too much work. That chain guide will be a piece of cake. Bending a few (hundred) valves during development has got to be more gratifying than driving a car you built ,tested and tuned a few thousand miles for about 5 total minutes of drag racing . Yup Drag Week is off, on with 100,000 mile 427 Cammer development. LOL


BTW Cant wait for next weeks report!

Go Jay!

Lance