3.2L P/C's pricing anomaly - way le$$ for Euro's (=more HP)???

[TedSlick]

In doing a rebuild, is there any reason to go with stock US spec (95mm) P/C's rather than Euro spec version which yields more HP?

Euro's being far cheaper, is there any downside to going Euro, such as necessitating other upgrades? Any upside staying stock US spec? I can't make sense of this (scratching head)...

[Wayne 962]

914s are the same way - the USA ones are much more expensive, since not as many people buy them. The Euros should give you more compression and a bump in HP. Just make sure your gas is good enough to handle the higher compression...

-Wayne

[TedSlick]

So would common California gas station fuel (91 octane) be a problem at higher compression ratio?

[Rot 911]

Originally posted by TedSlick
So would common California gas station fuel (91 octane) be a problem at higher compression ratio?

I researched using the Euro 3.2 pistons and cylinders during my still in progress engine rebuild. I concluded that unless you are guaranteed a ready supply of 93 octane gas or are willing to add octane booster that the euro setup is not the way to go. Keep in mind that the 3.2 computer does not have a knock sensor!

[TedSlick]

Thanks for these responses. So there is a downside.

What is it about Euro cars that affords them the higher compression setup? Is it that they have gas station fuel that much better in Europe (higher octane)? Did the U.S. cars get purposely lower compression P/C's to deal with typical fuel supply conditions?

[dd74]

Simply put, we just don't have the right gasoline for such a conversion, particularly in California.

It's why, if I ever do a rebuild, I'm most likely going to stay with stock compression. I wouldn't want to rely on playing with octane boost mixtures or filling up with racing gas at $5 a gallon. If at all, building a high-compression engine for the street is really too risky for you and I, particularly when considering how car un-friendly our state is.

Honestly, I wouldn't be surprised if the octane fell lower at some point from where it now is at 91. All new cars have knock sensors in their computers. Older cars, like pre-computer 911s, aren't considered viable losses in this action.

Put it to you this way: there's a ma and pop autoparts near my house where Eddie Van Halen buys octane boost for his Lambos -- buys them, that is, by the case.

A purchase by Eddie alone pays the store owner's rent.

[Wayne 962]

It's a gamble sometimes, but I think in most cases it might be okay. If not, then you would need an aftermarket fuel injection system, or a remap of the Motronic chip to back off the timing a bit to prevent detonation...

-Wayne

[Kahuna]

My euro Carrera pings on 93, under load, on really hot days.

[TedSlick]

This is the kind of feedback I needed. Thanks for helping me make an informed decision.

[aigel]

Ted:

The gasoline isn't necessarily "better" in Europe. There was leaded gasoline for a long time though which really helps with high compression too. Of course, with the Pb in the gas, no catalytic converters until the late 80s in Germany either. I would guess the 964 was the first 911 that came with converters in Germany. This is just a guess though.

Many folks in CA cringe if it comes to euro motors. Bruce Anderson is one of them. I'd stay away from high compression unless you have an engnine management system that can handle it, or you have a race engnie with cams that overlap to the point where you need it / bleed off some compression, or of course if you have a toy that you can put booster / race gas.

Cheers, George

[Wayne 962]

On a side note, the gas here in CA is probably *not* good enough to run this high compression with an early, primative, no-knock sensor Motronic setup like the 3.2 has.

Of course, you never know, but if you start pinging - there is nothing you can do short of getting a custom chip made, or tearing down your engine to remove the high compression pistons.

-Wayne

[MoreGAS]

This is the kind of feedback I needed. Thanks for helping me make an informed decision.
__________________
-Ted
'85 Targa


Don't pull the trigger too fast Ted
It occurs to me in this discussion that NO ONE has CC'd a euro 3.2 L piston nor a USA likely and determined its compression ratio.
What do you think they are ?
What do you think the limit is with 91 pump gas(oxygenated fuel)?

Could one do anything affordably to gain back some deto/thermal limit safety?>> change spark plugs, adjust fuel quality switch, ditch the cat as most do between smogs, do a proper chip, other creative avenues? Certainly a CC set up and then a dyno would be a great place to prepare from, no? Can a guy spend 3500- 5K++ building an engine and not desire to set it up on a dyno for a few hundee?

Truth is re cost; most likely the difference in price is resulting from the fact that the euro units do not sell nearly as often and thus in the past 2 yrs with the "cratering" dollar, the older euro units on the shelf are selling at a real bargain having been bought with, and priced at a USD nearly 20-35% stronger.

As always, best advise is DO YOUR HOMEWORK.

Kevin Roush
GAS Motorsport
Performance Porsche