QUOTE(jgara962 @ Dec 2 2010, 12:54 PM)
QUOTE(jgara962 @ Dec 2 2010, 11:34 AM)
What if you are running 2.0L pistons and cylinders? Still 87?
Sorry, I meant to ask about a 2.0L with higher compression euro pistons and cylinders.
Like Mark said above, it depends upon the actual compression ratio of your engine build.
Then you can compare that to say mfgr. reccos on a Euro 2.0 (maybe a Euro member/owner has their owners manual that they can tell you, but my info below says 95 RON Premium).
IIRC the stock Euro 2.0 was 8.0:1 & US was 7.6:1 (see below).
FYI All -
Here are the "stock" factory CR's from my 914 Spec Book
- (5/1/74 1st Ed. - so no 75-76 MY info):
Click to view attachment69/70-70 MY to 71/72-72 MY "W" & "EA" 1.7L's = 8.2:1 w/ 80 hp - 98 RON
> & for 72/73-73 MY Euro EA 1.7L's
72/73-73 MY "EB" 1.7L's = 7.3:1 w/72 hp - 91 RON
> (only about 7.0:1 w/ 69 hp in Calif 1.7L's - IIRC)
73/74-74 MY "EC" 1.8L's = 7.3:1 w/ 76 hp - 91 RON (incl. Calif)
73/74-74 MY to 73/74-74 MY "GA" 2.0L's = 7.6:1 w/ 95 hp - 91 RON (incl. Calif)
> (73-74 MY Euro "GB" 2.0's were 8.0:1 w/ 100 hp - IIRC)
.
My early 73 MY 914 1.7/2.0 Owners Manual (a new/NOS original replacement purchased in 2009 & in English) appears to be showing the Euro specs EA & GB motors (EA as noted above),
&
GB at 100 hp DIN (95 hp SAE) with 8.0:1 - & recco's 95 octane Premium fuel.
For comparison on the USA 2.0L GA spec, the DIN is 95 hp & SAE is 91 hp at 7.6:1 per the above spec book figures.
So you'll hear differing hp numbers on these engines, depending on whether it's quoting DIN (Euro) or SAE (USA) testing/rating standards.
Another factor affecting pinging/knocking & fuel grade is altitude, since the thin air high up exacerbates the problem in some cars.
Interesting thread!