Totally useless 60? to 90? Looper comparison

[ChrisAG]

I'm wondering how the "newer" 1.7L 115 hp loop-charged engines from 1995 and up (be they carbed, Ficht, or E-tec), compare to the old-school 120 hp 90-degree V4 2.0L engines from the late 1980's-mid 1990's in terms of torque and top speed (I don't think OMC ever made a 115 loop-charged 90?-V4)

Why ask, you may ask? Just curious as to wether the redesign is truly better than the proven performers. Those older 2.0L models had a reputation for being strong, reliable engines - did the 1.7L improve on that?

(Please no Ficht bashers - the V4 Ficht was a decently reliable engine compared to the V6)

 

[GatorMike]

Re: Totally useless 60? to 90? Looper comparison

Are you sure a crossflow V4 is 2.0 Litre? I always thought they were 1.6 litre. Oops I misread your post. You weren't talking looper vs crossflow.

 

[ChrisAG]

Re: Totally useless 60? to 90? Looper comparison

Never mentioned crossflow - all engines I'm talking about here are loop-charged - that's why I'm interested in the comparison - 90? 2 Litre versus 60? 1.7L, at roughly the same horsepower (120 vs. 115).

 

[trendsetter240]

Re: Totally useless 60? to 90? Looper comparison

Well, I don't know enough about the 120hp 90 degree v4 to offer much of a comparison. I sure someone with more experience will have some input.

I will add that Ficht and Etec are not loop charged, they are direct injected which is different.

 

[ChrisAG]

Re: Totally useless 60? to 90? Looper comparison

Ficht and E-tec engines are loop-charged AND direct injected.

Direct injection is a fuel delivery method; simply a different way of getting gasoline into the combustion chamber. The old way was to use carburetors.

Loop-charged versus cross-flow charged differences lie in the piston shape and scavenging method. Aside from a few cylinder head details, the engine block of a 1995 60-degree 115 is almost identical to an E-tec 115 (same displacement, bore, stroke). All 1.7 litre V4s are loop charged, right up to E-tec.

 

[Faztbullet]

Re: Totally useless 60? to 90? Looper comparison

The 60 degree is :
A) About 70 lbs lighter
B) Shorter stroke
C) Better Gear ratio
D) Better fuel economy
E) Better ignition system

 

[trendsetter240]

Re: Totally useless 60? to 90? Looper comparison

Ficht and E-tec engines are loop-charged AND direct injected.

Direct injection is a fuel delivery method; simply a different way of getting gasoline into the combustion chamber. The old way was to use carburetors.

Loop-charged versus cross-flow charged differences lie in the piston shape and scavenging method. Aside from a few cylinder head details, the engine block of a 1995 60-degree 115 is almost identical to an E-tec 115 (same displacement, bore, stroke). All 1.7 litre V4s are loop charged, right up to E-tec.

I stand corrected. I do understand how loop charged scavenging works. I thought that you wouldn 't refer to a direct injected 2-stroke as loop charged since only air comes in from the crankcase. But I was wrong.

Cheers

 

[Chris1956]

Re: Totally useless 60? to 90? Looper comparison

Loop Charged refers to the number and type of transfer ports in a 2 cycle motor. Cross-flow motors have one or two transfer ports. Loop Charged motors have 3 or more transfer ports. Crossflow motors use pistons with some kind of projection on the crown to help sweep (or scavange) the exhaust gases out. Loop Charged Motors use a flat head piston, and the transfer of the fuel charge from the crankcase scavanges the exhaust.

BTW - the e-TEC and other direct charge motors injest the oil and air charges via the crankcase thru reed valves. Only gasoline is injected into the combustion chamber, after the transfer and exhaust ports are closed. This cuts down on the amount of oil that is burned, as well as the emissions.