[rohrt]

I could use some education on the differences here. Is there any decisive reason to pick one over the other other then price?

I know the Simms has the Torrington thrust plate. I don't see that on the CC timing chain.

https://butlerperformance.com/i-3078...timing%2Bchain


https://www.bopengineering.com/A_Pon...lvetrain.shtml

[Tom Vaught]

Don't really need the Simms Torrington thrust plate, in my opinion, until you move into the
Higher Lift Roller camshaft profiles. But it you install it, the plate doesn't hurt anything.

Now the Roller cams will be a lot happier if they are located basically in one position (front to rear) in the block. Both the Simms and the BOP do that task.

For racing probably a great durability part. Street use the same durability assumed.

Week-end drivers, maybe the parts need to be used by someone else, in my opinion.
Both Pontiac companies have been around for a long time.

Tom V.

[25stevem]

Like Tom posted, it’s a waste unless your running a solid roller .
I had a solid roller in one of my street 455 engines and put 20K miles on it with the stock cam retention plate and would do so again in a Heartbeat.

If you have money to burn I would think about ditching the chain drive and installing a duel idler gear drive considering how crappy some chains are today and how off some of there timing marks have been reported to be!

[mgarblik]

Personally feel the torrington bearing timing set falls into the "nice to have category" vs the "need to have category". Raced Pontiacs for 45 years from 350 HP to 3500 HP. Never found the "need" for it. But it might eliminate a tiny bit of friction from the front of the engine and a few tiny shavings that would end up in the oil pan from the wear on the thrust plate. Typically, after years of racing, I may see .005-.007" wear in the plate. The SIMS set-up looks very nice and I would probably have used them in the past but he doesn't use the Cloyes timing sets for the modification. I prefer the Cloyes timing sets to the Rollmaster Brand he uses.

[TCSGTO]

I sent him my Cloyes billet set and he modified it for the Torrington bearing. I already had it and didn’t want to buy another set. Good guy to work with.
He will only machine billet gears.

[racegto65]

I've had Scott modify 3 gear drives for me. Great guy to work with and very nice parts.

[Don 79 TA]

Originally Posted by racegto65

I've had Scott modify 3 gear drives for me. Great guy to work with and very nice parts.

what kind of gear drives?
any issues?

[Schurkey]

The OEM thrust plate has no needle rollers that can come loose, fall into the pan, and lock-up the oil pump. A screened pump pickup would be mandatory; the pickups with "punched metal" might be too coarse.

Roller-bearing timing gears are not a risk I'd take, at least not on a street engine expected to go years between inspections.

[racegto65]

Originally Posted by Don 79 TA

what kind of gear drives?
any issues?

All are Pete Jackson drives and no issues. Been running 2 of them for years in my race car, 3rd is for a new combo.