Why power difference between ROW & US 930's?

[skipdup]

SO many questions!

For 1978 & 79 930, the ROW cars are rated at 300HP & 412Torque, while the US cars are rated at 265HP & 395Torque... a difference of 35HP & 17Torque.

ROW 930's required 98 Octane while US 930's required 96 unleaded.

ROW had "secondary air injection", but the US cars had "secondary air injection+thermal reactors+exhaust gas recirculation".

I also know the exhaust was routed very differently on ROW vs. US.

Is the different exhaust and additional emission equipment (thermal reactors & exhaust gas recirculation) the only reasons for the difference in power? Any other differences between ROW & US? Why the higher octane requirement for ROW cars?

I was told my thermal reactors and air circulation had been removed. Can anyone explain how I would confirm that? I don't know what to look for.

What about exhaust gas recirculation? Is there a benefit to removing? How do I tell if it's already been removed?

Many thanks!
Skip

[dean]

I think it is mostly the stinky exhaust on the US cars that caused the lower power. The Euro exhaust headers look just like what is found on an SC or a Carrera.

[TerryH]

Typically RoW cars had higher compression which would explain the required higher octane.

[RarlyL8]

The HP difference in Euro 930s vs US 930s is ONLY the exhaust. If you replace your US crap with a Euro exhaust you will get your 300HP.
(See these same statements in your other post)

There were also differences in the timing curve and CIS. (This accounts for the higher octane needed for ROW cars). When you change your exaust you should also consider bumping the timing. If your motor is a 930/63 California version it is just easier to swap out distributors. The CIS differences are not significant until you start pumping >350HP. At that point the Euro injection system has a bit of an edge.

Yes the picture you showed in your other post has no thermol reactors or air injection. See the shorty headers comming directly from each cylinder? Those are aftermarket thermol reactor replacements. The original thermol reactors are large tube looking things that held in a tremendous amount of heat.
The air injection spider ports have been plugged by small 10mm allen or hex head bolts. You can see them if you look on the bottom of each cylinder by the exhaust port.

Pick up a Euro exhaust for $200-$500 and bolt on 35HP.

[skipdup]

Perfect... Exactly the information I was looking for. Thanks!

Also, my brain must not be working right tonight... My two posts really should have been combined a they were so similiar... very long day...

- Skip

[TerryH]

Originally posted by RarlyL8
The HP difference in Euro 930s vs US 930s is ONLY the exhaust. If you replace your US crap with a Euro exhaust you will get your 300HP.
(See these same statements in your other post)

I stand corrected. The RoW, "normally aspirated" engines, typically have higher compression than their US counterparts.

[cowtown]

Originally posted by RarlyL8

Pick up a Euro exhaust for $200-$500 and bolt on 35HP.

It's also got to be at least 15-20 pounds lighter than the reactor setup.

[RarlyL8]

You can throw out a LOT more than 20# worth of trash on these motors. The exhaust is just the begining. Air pump, hoses, switches, gizmos, spiders, it's unbeleivable how much crap they layered on that poor engine in the name of emmision control.

My 930/63 California scrapheap wieghed 529# complete from air cleaner to muffler. I weighed it myself on a drum scale. Makes a V8 swap look like an upgrade.

[t.brady]

were changes were made to the later US exhaust systems ('86 - '89)?