[RWS]

The engine in my ‘70 RA III Formula was getting tired after 100 k miles since it was first rebuilt (in 1975!), so I started buying everything needed to rebuild it a second time.

The water pump began to leak before I was ready to pull the engine, though, so I decided to replace just that and keep driving the car until the fall.

Glad I did as it became clear that there was lots of slack in the timing chain, so in went the new timing gear set I already had on hand.

Happily, the improvement in performance was incredible, no doubt as cam (and therefore ignition) timing was badly retarded.

Bottom line is that I can put off rebuilding the engine for the foreseeable future, although I will have to find a better place to store all the internals I accumulated over the last two or so years

[TXSTARFIRE]

Cam timing would be retarded but normally ignition timing is checked and set at every tuneup so that should have been OK.

[F Body Freak]

To piggyback off of this thread...

My 70 Formula is currently disassembled to the timing chain & with 99K miles on it, it appears to have quite alot of slack in it.
Summit seems to have about 50 options & I wondered what was recommended as a good timing chain for a 1970 400? Completely stock.

[SD455DJ]

We replaced the original factory (nylon tooth) timing chain and gears with Cloyes C-3007K stock replacement parts. The RAIII is completely stock including the 068 cam & lifters. We had to replace the factory front cover as it was totally eroded and turned to dissolved guck. It had 46,000 original miles when it was replaced a few years ago.

Dennis

[F Body Freak]

Appreciate it, Dennis.
Nice to see a picture of the original nylon tooth chain & gears. Mine does not look like that anymore.


Rod

[F Body Freak]

Threw that new Cloyes chain on today. Nice to have the slack gone from that old chain. There was quite a bit. I noticed the old gear had GM & Morse on it like people have talked about with the nylon gear. Not sure if that means anything. I assume it was just replaced with another GM set.

Rod

[SD455DJ]

Looks like your timing gear/chain set was replaced with the '71-up pieces when the original nylon gear gave up the ghost.

Dennis

[F Body Freak]

Quick question with this...
Engine ran fine before disassembly. Broke a water pump bolt off in the timing chain cover was the only reason it was tore down this far. Seen the chain was sloppy so I decided to replace it. This should be cut & dry, I think. The distributor has not been removed. The timing chain gears only go on one way due the keyways, so with the distributor still in the engine, the timing marks shouldn't need lined up, correct?My son in law says "but if you move the cam or crank while putting the chain on it'll be off" I can't move either one of those by hand.

[johnta1]

What should be done before taking off old one is align the gears 'dot to dot', I like it with the cam gear dot down and crank gear up. If the dots are aligned take off gears/chin and replace. Should be still at 'dot to dot'.

if it was not done that way, rotate the crank to get it to 'dot to dot'.
Should be at tdc, take cap off distributor and see where the rotor is pointing to which plug wire. Should be 6.

[F Body Freak]

I'll do that & see where the rotor is. Thank U

[F Body Freak]

I spun it around where the crank gear did about 3 rotations, so the marks were dot to dot twice. When the cam gear is at 6 & the crank gear is at 12, the rotor is pretty much pointing at #6 cylinder.