final build advice

[cmcfaul]

Getting ready to put it back together.

2.4 E engine with new JE pistons.

1. Do I need to replace the flywheel bolts?
2. I bought new rod bolts, do I also need new rod nuts?
3. Should I replace the fly wheel pulley with a bigger one to get more cooling...it does tend to run hot in the summer in traffic
4. Any other details or tricks to the trade I should be aware of.

Many Thanks

Chris

73 911 E

[Eagledriver]

I'm not afraid to re-use flywheel bolts, but others will disagree. They should be at least inspected, make sure the heads where the star bit goes isn't stripping. Old rod nuts are fine if in good shape. I would not use a bigger pulley for the fan system, but you could use a front oil cooler.

[Henry Schmidt]

See answers below in red

Originally Posted by cmcfaul

Getting ready to put it back together.

2.4 E engine with new JE pistons.

1. Do I need to replace the flywheel bolts? The 2.4/2.7 crank has inherent flaw. At rpm the crank tends to flex creating a rocking couple that results in an imbalance. This imbalance creates a vibration and at sustained higher rpm will cause the flywheel to loosen. We always use new bolts for this reason. In some applications we even use a better quality bolt.
2. I bought new rod bolts, do I also need new rod nuts? We always replace nuts as well but never use the stock nuts even with stock bolts. We use a serrated flanged, 12 point nut in this application.
3. Should I replace the fly wheel pulley with a bigger one to get more cooling...it does tend to run hot in the summer in traffic. Pulley size is strictly a function of engine rpm. If you spend a lot of time at low rpm a large pulley may help. Like everything else, engine building entails compromise, if you gain cooling at lower rpm you will lose cooling at higher rpm.
4. Any other details or tricks to the trade I should be aware of. There are a plethora of updates that improve the general performance and reliability of the 911 engine. Listing them all would require book. If you stick to proven methods you should be fine.

Many Thanks

Chris

73 911 E

[cmcfaul]

Thanks everyone.

To be on the safe side, going to get new flywheel bolts and new rod nuts (sounds funny;-). Likely both from Henry along with the bearings if not too outragous.

Chris

[304065]

The factory flywheel bolts, in addition to being about $13 each, are single use torque-to-yield type, which means they permanently elongate when clamp load is applied.

After going through two sets of these I went with the ARP 204-2802 and am very pleased with the product, the installation instructions and the price.

[cmcfaul]

I ended up going with the ARP flywheel bolts, new crank, case savers, blueprint and balance, oil bypass mod, pressure relief kit, steel studs and Westwood Racing seal kit. Plus other machine shop details around reconditioning the rods, etc.

That should cover the bottom end. Should have case back tomorrow and pistons on Friday :-)

Chris,

73 911 E