Engine Diffrences.
Thread Starter
Nordschleife Master
Joined: Aug 2002
Posts: 9,010
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From: South Texas
Engine Diffrences.
What is diffrent between the US and Euro engines in the 1980 cars?
Is the 80 Euro realy 300hp, while the 80 US is only 219hp? Also, was the 83 Euro 300, while the US was a mear 234hp?
If so, what is the diffrence?
(and would it be possible for me to "upgrade" my 83 US to 300hp euro spec?????? ;-))
Thanks.
Is the 80 Euro realy 300hp, while the 80 US is only 219hp? Also, was the 83 Euro 300, while the US was a mear 234hp?
If so, what is the diffrence?
(and would it be possible for me to "upgrade" my 83 US to 300hp euro spec?????? ;-))
Thanks.
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Rennlist Member
Rennlist Member
Joined: Jul 2002
Posts: 2,693
Likes: 52
From: AZ
The L-Jetronic US and Japan engines were designed to meet SMOG requirements and lower octane fuel. They weren't changed while the Europe and ROW engines were improved. Remember, back then the US had our famous 55 MPH speed limits, anything above a riding lawn mower could "park" on the freeway.
There were two generations of the Euro high-end engines. Don't be fooled, not all Euros had the higher HP engines, they were optional!! The '80 - '83 engines "S" retained CIS injection, but had higher compression and larger valves (the same size as 944 valves). The intake runners and throttle valve were larger. The cams were more aggressive. The '84 to '86 "S2" model was upgraded to LH-Jetronic injection and sported the twin 4 cylinder "grafted together" distributor. These models were spec'd at 310 hp.
Porsche Cars North America doesn't sell non-US parts. So you have to find your Euro pars elsewhere. Used engines are few and hard to come by. If you find them parts are pretty expensive.
One way to get the extra HP has been discussed over the years .... "graft" the Euro top-end to a 5.0 liter US (32 valve) block. You need to grind some relief holes in the piston for valve clerance. If your 928 is an '80 - '84 model, you need to do some fancy grinding to get the L-Jetronic MAF to mate to the LARGER euro throttle housing.
With this work you should have a smog legal motor that outputs about 270 RWHP, power right up there with S4s. If you add headers and low restriction exhaust you'll climb up to 280 - 290 RWHP. My '79 Euro track beast is made from the above formula. I retained the '79's CIS injection and it works just fine.
There were two generations of the Euro high-end engines. Don't be fooled, not all Euros had the higher HP engines, they were optional!! The '80 - '83 engines "S" retained CIS injection, but had higher compression and larger valves (the same size as 944 valves). The intake runners and throttle valve were larger. The cams were more aggressive. The '84 to '86 "S2" model was upgraded to LH-Jetronic injection and sported the twin 4 cylinder "grafted together" distributor. These models were spec'd at 310 hp.
Porsche Cars North America doesn't sell non-US parts. So you have to find your Euro pars elsewhere. Used engines are few and hard to come by. If you find them parts are pretty expensive.
One way to get the extra HP has been discussed over the years .... "graft" the Euro top-end to a 5.0 liter US (32 valve) block. You need to grind some relief holes in the piston for valve clerance. If your 928 is an '80 - '84 model, you need to do some fancy grinding to get the L-Jetronic MAF to mate to the LARGER euro throttle housing.
With this work you should have a smog legal motor that outputs about 270 RWHP, power right up there with S4s. If you add headers and low restriction exhaust you'll climb up to 280 - 290 RWHP. My '79 Euro track beast is made from the above formula. I retained the '79's CIS injection and it works just fine.
