I was talking to a guy on the Ford Motorsport stand at the Autosport show about the delays with the Focus RS and he said that before an engine is signed off for production, it must undergo tests including 18 hrs. continuous flat-out (What flat-out means in this context, I don`t know - load, revs etc) without failure.
My point is, what is the Subaru production criterea, and could you imagine your engine holding together on such a test? With all the big-end and distorting piston (slap) problems we hear about here I begin to wonder about the mechanical integrity of our hardware!
Does anyone know the pre-production test regime?
JohnD

 

John

Ford do test their engines well (ie very hard) prior to test, but so do other manufacturers.

The hardest tests to get an engine through are not the continuous high speed / load tests. Once the engine gets to the point of full heat soak (ie, all components are up to their maximum temperature including turbo, oil etc) the test can start. Generally, component failures occur fairly quickly if at all. The harder tests are the cold start, max power test. Imagine a scene if you will .....

[flame suit on]
Wifey starts her days driving. She loads up her 1.0 Fiesta and takes it out onto a busy road. Max revs (still cold) in every gear for 1/2 mile. Stops at school to drop off kids, gossips to friends for 30 minutes, car cools down again. Back in car, max revs in every gear, 1/2 mile later stops at supermarket to get some shopping. 30 minutes later, car cooled down again, ....
[flame suit off]

An alternative is garage mechanic test driving the car after a service .......

When trying to productionise the Sierra Cosworth engine we had to pass a number of tests, including one that Ford had at the time. The test required the engine to be started cold, no throttle for 10 seconds. Then full throttle at 90% of max revs for 3 minutes - engine goes from cold to bl00dy hot. Don't forget, this represented over 200 BHP, not the candlepower put out by a 1.0 Fiesta! Switch off (no idle to cool turbo), and quench by passing cold water through system to cool back to under 10C in under 2 minutes. Tough test? Well, maybe not once, but the engine was put on this cycle (5 minutes a go) for 36 hours contiuously, no maintenance....

Suffice to say, the first few times bits dropped off , but it soon shows the weak points of the engine.

First few times the engines failed the test, the management argued with Ford that test was unfair as nobody (Imatrucksa excepted ) drives a Cosworth like that. Ford went away and came back with some German service claims for head gasket failures. One, a Ford Europe Director , his daily commute consisted of less than 300 m to the autobahn, then straight up to 150 mph for about 30 km, then at the other end about 500 m to his parking place at work. Strangely, he had gone through 3 head gaskets in less than 6 weeks, and it couldn't be his fault.

Eventually, the engine was ammended to pass the test.

Do FHI put their engines through similar tests? My guess is yes, but I don't know for a fact.

Duncan

 

Honda have a big plant in Swindon as you probably well know. My neighbour is one of the Manager type people, and he told me once that as part of their QC procedures they randomly pick an engine and run it for 24 hours non stop at or just below rev limiter.

 

At October 1996 a Forester Turbo won the Indianapolis record (Hulman award) with 180,082 km/h continuously!
If that means something.
JIM

 

Thanks for the info. guys.
Duncan Those tests are horrendous! makes fasinating reading. I`ve always had a high regard for Ford, and still say the variuos Cosworths were the definitive performance saloons. It`s such a pity they have lost so much ground with the Focus RS delays.
Does anyone know the Subaru test regime?
JohnD

 

I know Lotus used to heat soak test the Esprit turbo somewhere in southern Spain, by getting the engine bay absolutely cooking, taping up all the cooling ports, and switching it off, several times a day for weeks on end.

 

Subaru motors are increadibly reliable, so much so they use them in smallish aircraft.
Dan

 

Overboost must be an interesting experience in an aeroplane.

[Edited by nigelward - 2/13/2002 8:18:37 AM]

 

wouldn't it be similar to the afterburner effect

 

All Ferrari engines are bench tested for hours solid at red line rpm's. If they blow up they're no good. If they survive into customer's cars who treat like new for 1000 miles.

They have 3 "bomb" proof test bays! Only 1 engine has blown & that was a 1995 v12 F1 engine,

 

Double posted!

[Edited by JIM THEO - 2/11/2002 5:21:29 PM]