A lesson from VW

On 11/10/2018 at 6:04 PM, Jan van Eck said:

Ron, better make sure your daughter is careful to put only premium fuel, at least 91 octane, probably better at 93, given that that little engine is set up at 10-1/2 compression ratio. 

Historically I'd definitely agree with the octane guidelines, but with a modern direct injection motor, metering, and sensors, I think you can get away with the lower octane. I do stick with synthetic oil though.

Ten years ago I had hopped up rice rocket running 10-1/2 to 1, plus running a 15.2PSI boost and I drove the piss out of it, though never intended to keep it past the warranty. The modern engine management systems, programming and sensors constantly are monitoring and adjusting, or you'd blow the motor to bits in no time. Today the gas pedal is really just an input to a computer, not a direct command. 

Today I drive a run of the mil Honda Accord, 2.0 turbo, feed it regular, and it never balks. Scary quick for a mundane family sedan. And 30MPG for average driving though I can coax 40MPG out of it on the highway, but not much fun in staying 65-70. 

My '92 Volvo with 8.0 compression, and a low turbo boost, massively oversized crank and bearings bearings, and I'm not sure you could blow that motor, and the turbo would give out before the motor did leaving it woefully underpowered. Loved that Volvo, and only sold it because I left the country. At 15 years old it didn't even feel broken in drive train wise. In those years it was twice hit by other cars, and they were totaled, and it just kept going. 

With my '60s era hobby cars to set the timing I'd put the level of gas I planned on, and would advance/retard the timing by hand so it would just ping if I loaded it up at 2000RPM in 3rd (4 speed). I did go solid state Petronix and dumped the points/condenser. But getting 40MPG with the option of going 150 mph if had a death wish, that's can't be done with 60s iron set up.

Share this post


Link to post
Share on other sites