Amsoil Engine Tear Down Pics

Here is one from Red Line previously posted.

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Good looking engine. Surprise for me as I didn'think GM could make a good 4 cylinder engine.
Was this mostly highway miles or stop and go commuter service??

My 2¢

Looks not very far from brand new.

G.M. did not even come close at one time. Years ago their 4 cyl engined cars were knicknamed "throw-away-cars!" They were really so very bad they were a complete horror show. Many failed (meltdowns) before they were even paid off by the poor buyers who trusted and took chances with Chevrolet.
Chevrolet , they actually got lucky and made a pretty good one in partnership with an English firm while John Delorean was running some parts of GM again. The Cosworth Vega twin-cam fuelie was quite the handfull in the small package body it was installed into. Problem was they cost a lot and consumers lost faith too quickly while GM was working out some (first year) bugs that always happens.
It appeared the General had finally found & hired some folks with experience with the very small cui motors , some in aluminum.

The Chevrolet Cosworth Vega was a four-passenger automobile produced for the 1975 and 1976 model years. It is a limited-production version of the Chevy-Vega subcompact with higher performance designs. Chevrolet developed the car's all-aluminum in-line 122 cu in (1,999 cc) engine, and British company Cosworth Engineering designed the DOHC cylinder head. 5,000 engines were built. About 3,500 cars were made before being given up on. They were priced nearly double that of a base Vega and only $900 below the 1975 Chevrolet Corvette.[1]
The Cosworth Vega Twin-Cam engine is a 122 cu in (1,999 cc) inline-four with die-cast aluminum alloy cylinder block and Type 356 aluminum alloy, 16-valve cylinder head with double overhead camshafts (DOHC) held in a removable cam-carrier that doubles as a guide for the valve lifters. Each camshaft has five bearings and is turned by individual cam gears on the front end. The camshafts, water pump and fan are driven by a fiberglass cord-reinforced neoprene rubber belt, much like the Vega 140 cu in (2,294 cc) engine. The cylinder head has sintered iron valve seats and cast iron valve seats. Race-bred forged aluminum pistons with heat-treated forged steel crankshaft and connecting rods enhance durability.[6]
The engine has a stainless steel exhaust header and Bendix electronic fuel injection (EFI), with four injector valves, an electronic control unit (ECU), five independent sensors and two fuel pumps. Some 60 lb (27 kg) lighter than the SOHC Vega engine,[4] it develops maximum power at 5,600 rpm and is redlined at 6,500 rpm, whereas the SOHC Vega engine peaks at 4,400 rpm and runs to 5,000 rpm. Final ratings are 110 hp (82 kW) at 5,600 rpm, 107 lb⋅ft (145 N⋅m) of torque at 4,800 rpm.[7] 3,508 of the 5,000 engines were used. GM disassembled about 500 and scrapped the remainder.[8] These cars are very rare today with some in amazingly complete operating condition and are sought out by collectors heavily. They are very fast small cars with great suspension and handling and said were ahead of their time when originally released to the general public.
 

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It's one of those interesting GM projects, but a very fast small car it is not.

1/4 mile in 18.5 seconds.

https://www.curbsideclassic.com/vin...ce-one-for-twice-the-price-of-a-mediocre-one/
yeah, another interesting GM project that failed is a better description. A shame as they seemed to have a lot of potential and lots of room for improvement. Certainly was the right time for a good 4 cyl car to come along. Japan was leaps and bounds ahead of us and sold lots of them in those years that followed.
 
Found this on a FB group, thought I'd share it. Who doesn't like good tear down pics?

Background:

"2012 Cruze Eco 1.4L Turbo. This car has seen nothing but AMSOIL Signature Series 5W-30 since 2013, and has been tuned since as well, first with Trifecta then with BNR, making about 50hp and 70lb-ft more power *to the wheels.* Starting in about 2015, the car was used to tow my 14' boat as well as my utility trailer and various uhaul trailers. Since I started working from home full time in 2015, most of the driving was short trips, wide open throttle to redline daily.
At 72k miles, I pulled the cams to upgrade valve springs. The oil in service at the time of this disassembly had 12,500 miles and 2 years on it, about 1/4 of which was with a trailer behind it and the rest of it hitting max boost daily. I stopped caring about fuel economy once I stopped commuting. The oil change prior to that went 15,622 miles and 18 months, and all oil changes before that were at 10,000-15,000 miles (dealer drained it a couple times to service the oil pan and PCV system or they'd all have been 15k miles)."

View attachment 148247View attachment 148248View attachment 148249View attachment 148250View attachment 148251
It looks about the same as a 45 year old locomotive engine with 200,000 hours.
 
Interesting that there is a little varnish or some form of deposit. I'd suggest a shorter OCI.

Almost any engine is capable of a long service life with adequate oil and OCI's.

My Jag 2.5L with 225K looks cleaner than that.
Heard that before. Show and tell.
 
It's one of those interesting GM projects, but a very fast small car it is not.

1/4 mile in 18.5 seconds.

https://www.curbsideclassic.com/vin...ce-one-for-twice-the-price-of-a-mediocre-one/


Hold on… :LOL:

I’m joking here but I have to say the following.

On Street Outlaws Shane ran that Blackbird Vega and it was legit stupid fast… Made it to #3 on the OKC list. And won a Cash Days in 2017… Though that final race against the Bird Boys got technically shut down early due to police coming down that same road.

Obviously that Vega was modified to hades wouldn’t have it… But it was a darn good race car. Light weight as all get out with steam roller back tires and a super charger on it etc etc etc.
 
Hold on… :LOL:

I’m joking here but I have to say the following.

On Street Outlaws Shane ran that Blackbird Vega and it was legit stupid fast… Made it to #3 on the OKC list. And won a Cash Days in 2017… Though that final race against the Bird Boys got technically shut down early due to police coming down that same road.

Obviously that Vega was modified to hades wouldn’t have it… But it was a darn good race car. Light weight as all get out with steam roller back tires and a super charger on it etc etc etc.
Nothing GM about that anymore though.
 
No Pentastar-style finger follower failure evident. Hate that design. Subaru went to it "For the 20" ... engines went soft.

In general Ring land varnish MUCH more important than a bit of VT varnish. But If its up top it's likely "down there" ignoring exhaust port varnish.

Is this oil BETTER than then new M1 FS? Could be.
 
No Pentastar-style finger follower failure evident. Hate that design. Subaru went to it "For the 20" ... engines went soft.

In general Ring land varnish MUCH more important than a bit of VT varnish. But If its up top it's likely "down there" ignoring exhaust port varnish.

Is this oil BETTER than then new M1 FS? Could be.
You hate roller followers rather than bucket? Why exactly?
 
You hate roller followers rather than bucket? Why exactly?
Bad design utilising a low class - high load lever action - plus hydraulic limitations. Frequent failures - short service life.

Subaru EJ and Honda SOHC had a decent non-hyd design with cam under shaft mounted roller rockers
with large circumference rollers to keep speed down. Other than that, it is hard to complain about inverted buckets under oil
for simplicity - though an infrequent adjustment can be difficult.

Is this switch to rollers all driven by low saps 20 grade and even lighter oils? Maybe.
 
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