[Money Pit]

Is the BOP belt drive that much better then a good Cloyes chain set-up. So is the cost of the BOP set-up really worth the it?

[AIR RAM]

I have never used one, however I have been looking at / considering one for my current build.

I would think it all depends on what you need from the engine. What they do is remove harmonic transfer from the crank to the cam which transfers those harmonics to the top end. So the gains would be what ever is effected by the removal of those harmonics.

If you own a dedicated track car and you are wanting/needing the absolute best performance and engine reliability... then I would say yeah, its worth it. I think you gain more in greater control of harmonics equating to cam bearing life and possible distributor gear life with improved/more consistent timing events... (Possible improved lifter life) I dont see you gaining anymore than single digit HP though if any HP gains at all.

I could be wrong though...

SPEED SAFE, NICK

[3fastgtos]

I had the BOP belt and front dist. on my last N/A engine. Now I’m going back to a chain and rear dist. I think it’s just simpler, if one works in the Boss Bird then I’m not gonna worry about it. You can get more of an exact cam timing with the belt, easier to play with on the dyno for that last available horsepower.

[mgarblik]

Originally Posted by 3fastgtos

I had the BOP belt and front dist. on my last N/A engine. Now I’m going back to a chain and rear dist. I think it’s just simpler, if one works in the Boss Bird then I’m not gonna worry about it. You can get more of an exact cam timing with the belt, easier to play with on the dyno for that last available horsepower.

I have great respect for Wade and all they do for the Pontiac Hobby. I think the belt drive system is really cool and makes camshaft timing changes much easier and faster than a chain drive. That can be a real benefit when changing camshafts regularly and tuning for every last HP under all conditions. The primary reason we run a timing chain is:

1. The cost factor is 10% of a belt drive
2. The direct HP benefit is mostly conjecture all things being equal
3. A proper damper or blower belt will handle the supposed harmonic benefits of a cam belt drive
4. A chain drive is stone 100% reliable with zero failures in 22 years of racing at 1200-3500 HP Pontiacs in various configurations.
5. You have to wonder why almost every production engine out there has gone away from belt drives and is back to chain drives for OHC, DOHC and Pushrod engines.
6. In the Boss Bird application, the front of the engine is so busy with fuel, magneto, and blower drives, adding a belt cam drive would have been over the top and difficult to get to for adjustments anyway.

One point specifically for Mr. Dale, If you do decide to run a chain drive, PM me and I have a drawing I can send you to add a second keyway to drive the crank sprocket. It helps balance the load on a super high HP engine like you are building.

[3fastgtos]

Originally Posted by mgarblik

I have great respect for Wade and all they do for the Pontiac Hobby. I think the belt drive system is really cool and makes camshaft timing changes much easier and faster than a chain drive. That can be a real benefit when changing camshafts regularly and tuning for every last HP under all conditions. The primary reason we run a timing chain is:

1. The cost factor is 10% of a belt drive
2. The direct HP benefit is mostly conjecture all things being equal
3. A proper damper or blower belt will handle the supposed harmonic benefits of a cam belt drive
4. A chain drive is stone 100% reliable with zero failures in 22 years of racing at 1200-3500 HP Pontiacs in various configurations.
5. You have to wonder why almost every production engine out there has gone away from belt drives and is back to chain drives for OHC, DOHC and Pushrod engines.
6. In the Boss Bird application, the front of the engine is so busy with fuel, magneto, and blower drives, adding a belt cam drive would have been over the top and difficult to get to for adjustments anyway.

One point specifically for Mr. Dale, If you do decide to run a chain drive, PM me and I have a drawing I can send you to add a second keyway to drive the crank sprocket. It helps balance the load on a super high HP engine like you are building.

Timing chain is going in my new N/A engine. Blower motor gets a splined crank and a TFX front drive. Thanks for the offer however.
SD

[Mark G]

IMO not worth it you won't go any faster ...lol 64 Pontiac tempest chain here ..

[Jack Ferris]

I bought one because the price was right and I liked the motor plate set up. Doubt I would ever buy a new one.

[mgarblik]

Timing chain is going in my new N/A engine. Blower motor gets a splined crank and a TFX front drive. Thanks for the offer however.
SD

OK, got it. So the blower engine block is a billet utilizing the much larger snout, splined crank, and a TFX gear drive? Very nice. BTW, for your chain drive NA engine, Cloyes has a super high end chain available called the "Z" chain. Available only in standard length but 30% stronger than anything else they sell. When you order the billet set add a Z to the end of the part number to get that chain. It's available in 3 and 9 keyway billet sets only.